* [PATCH v3 0/4] Introduce the Counter character device interface
@ 2020-06-17 1:39 William Breathitt Gray
2020-06-17 1:39 ` [PATCH v3 1/4] counter: Internalize sysfs interface code William Breathitt Gray
` (3 more replies)
0 siblings, 4 replies; 10+ messages in thread
From: William Breathitt Gray @ 2020-06-17 1:39 UTC (permalink / raw)
To: jic23
Cc: kamel.bouhara, gwendal, alexandre.belloni, david, linux-iio,
linux-kernel, linux-stm32, linux-arm-kernel, syednwaris,
patrick.havelange, fabrice.gasnier, mcoquelin.stm32,
alexandre.torgue, William Breathitt Gray
Changes in v3:
- Remove string data type; there is no need to handle strings via the
chrdev interface
- Reimplement COUNTER_DATA_TYPE_ENUM using struct counter_available
- Refactor Count and Signal sysfs number as index offset rather than id
value; this should make the naming and paths more consistent
- Implement chrdev_format sysfs attribute; data format of chrdev is
configured via sysfs in order to keep data and configuration separate
Over the past couple years we have noticed some shortcomings with the
Counter sysfs interface. Although useful in the majority of situations,
there are certain use-cases where interacting through sysfs attributes
can become cumbersome and inefficient. A desire to support more advanced
functionality such as timestamps, multi-axes positioning tables, and
other such latency-sensitive applications, has motivated a reevaluation
of the Counter subsystem. I believe a character device interface will be
helpful for this more niche area of counter device use.
To quell any concerns from the offset: this patchset makes no changes to
the existing Counter sysfs userspace interface -- existing userspace
applications will continue to work with no modifications necessary. I
request that driver maintainers please test their applications to verify
that this is true, and report any discrepancies if they arise.
However, this patchset does contain a major reimplementation of the
Counter subsystem core and driver API. A reimplementation was necessary
in order to separate the sysfs code from the counter device drivers and
internalize it as a dedicated component of the core Counter subsystem
module. A minor benefit from all of this is that the sysfs interface is
now ensured a certain amount of consistency because the translation is
performed outside of individual counter device drivers.
Essentially, the reimplementation has enabled counter device drivers to
pass and handle data as native C datatypes now rather than the sysfs
strings from before. A high-level view of how a count value is passed
down from a counter device driver can be exemplified by the following:
----------------------
/ Counter device \
+----------------------+
| Count register: 0x28 |
+----------------------+
|
-----------------
/ raw count data /
-----------------
|
V
+----------------------------+
| Counter device driver |----------+
+----------------------------+ |
| Processes data from device | -------------------
|----------------------------| / driver callbacks /
| Type: u64 | -------------------
| Value: 42 | |
+----------------------------+ |
| |
---------- |
/ u64 / |
---------- |
| |
| V
| +----------------------+
| | Counter core |
| +----------------------+
| | Routes device driver |
| | callbacks to the |
| | userspace interfaces |
| +----------------------+
| |
| -------------------
| / driver callbacks /
| -------------------
| |
+-------+---------------+ |
| | |
| +-------|-------+
| | |
V | V
+--------------------+ | +---------------------+
| Counter sysfs |<-+->| Counter chrdev |
+--------------------+ +---------------------+
| Translates to the | | Translates to the |
| standard Counter | | standard Counter |
| sysfs output | | character device |
|--------------------| |---------------------+
| Type: const char * | | Type: u64 |
| Value: "42" | | Value: 42 |
+--------------------+ +---------------------+
| |
--------------- ----------
/ const char * / / u64 /
--------------- ----------
| |
| V
| +-----------+
| | read |
| +-----------+
| \ Count: 42 /
| -----------
|
V
+--------------------------------------------------+
| `/sys/bus/counter/devices/counterX/countY/count` |
+--------------------------------------------------+
\ Count: "42" /
--------------------------------------------------
I am aware that an in-kernel API can simplify the data transfer between
counter device drivers and the userspace interfaces, but I want to
postpone that development until after the new Counter character device
interface is solidified. A userspace ABI is effectively immutable so I
want to make sure we get that right before working on an in-kernel API
that is more flexible to change. However, when we do develop an
in-kernel API, it will likely be housed as part of the Counter core
component, through which the userspace interfaces will then communicate.
Interaction with Counter character devices occurs via standard character
device read/write operations. This allows userspace applications to
access and set counter data using native C datatypes rather than working
through string translations.
The following are some questions I have about this patchset:
1. Should the data format of the character device be configured via a
sysfs attribute, ioctl, or something else?
I believe it's good to have the configuration of the data format
separate from the actual data, but I'm not sure if that configuration
should be exposed via sysfs or some other interface. What interface
would be most fitting for such configuration?
2. Should the format of the chrdev_format attribute be more friendly for
a human user?
I implemented a minimalistic syntax for the sake of simplifying the
parsing code, but we could increase the verbosity a bit to make it
easier for humans to understand the format of the chrdev_format
attribute.
For example, "C0 C0E3 S1 C1E2" could instead be "Count 0, Count 0
Ceiling, Signal 1, Count 1 Floor"; because extension names are
required to be unique, it possible to refer to the extensions
directly by their names (i.e. "ceiling" and "floor") rather than
their index offset. The downside to this is of course the need for a
more complex parser.
3. How should alignment of the character device data be handled?
We might not need to handle this just yet, but I can envision
situations where it would be nice for user to specify the alignment
of the data in order to match the packing of a structure in a
userspace application. How we specify the alignment will naturally
depend on the syntax we decide for the chrdev_format attribute. I can
see a "padding" option as a possible solution, but it'll be nice to
get some feedback if there are any other ideas.
William Breathitt Gray (4):
counter: Internalize sysfs interface code
docs: counter: Update to reflect sysfs internalization
counter: Add character device interface
docs: counter: Document character device interface
Documentation/ABI/testing/sysfs-bus-counter | 31 +
Documentation/driver-api/generic-counter.rst | 280 +++-
MAINTAINERS | 3 +-
drivers/counter/104-quad-8.c | 474 +++---
drivers/counter/Makefile | 1 +
drivers/counter/counter-chrdev.c | 612 +++++++
drivers/counter/counter-chrdev.h | 23 +
drivers/counter/counter-common.h | 15 +
drivers/counter/counter-core.c | 187 +++
drivers/counter/counter-sysfs.c | 881 +++++++++++
drivers/counter/counter-sysfs.h | 14 +
drivers/counter/counter.c | 1496 ------------------
drivers/counter/ftm-quaddec.c | 59 +-
drivers/counter/stm32-lptimer-cnt.c | 161 +-
drivers/counter/stm32-timer-cnt.c | 139 +-
drivers/counter/ti-eqep.c | 211 +--
include/linux/counter.h | 628 ++++----
include/linux/counter_enum.h | 45 -
include/uapi/linux/counter-types.h | 34 +
19 files changed, 2748 insertions(+), 2546 deletions(-)
create mode 100644 drivers/counter/counter-chrdev.c
create mode 100644 drivers/counter/counter-chrdev.h
create mode 100644 drivers/counter/counter-common.h
create mode 100644 drivers/counter/counter-core.c
create mode 100644 drivers/counter/counter-sysfs.c
create mode 100644 drivers/counter/counter-sysfs.h
delete mode 100644 drivers/counter/counter.c
delete mode 100644 include/linux/counter_enum.h
create mode 100644 include/uapi/linux/counter-types.h
--
2.26.2
^ permalink raw reply [flat|nested] 10+ messages in thread
* [PATCH v3 1/4] counter: Internalize sysfs interface code
2020-06-17 1:39 [PATCH v3 0/4] Introduce the Counter character device interface William Breathitt Gray
@ 2020-06-17 1:39 ` William Breathitt Gray
2020-06-17 1:40 ` [PATCH v3 2/4] docs: counter: Update to reflect sysfs internalization William Breathitt Gray
` (2 subsequent siblings)
3 siblings, 0 replies; 10+ messages in thread
From: William Breathitt Gray @ 2020-06-17 1:39 UTC (permalink / raw)
To: jic23
Cc: kamel.bouhara, gwendal, alexandre.belloni, david, linux-iio,
linux-kernel, linux-stm32, linux-arm-kernel, syednwaris,
patrick.havelange, fabrice.gasnier, mcoquelin.stm32,
alexandre.torgue, William Breathitt Gray
This is a reimplementation of the Generic Counter driver interface.
There are no modifications to the Counter subsystem userspace interface,
so existing userspace applications should continue to run seamlessly.
Overview
========
The purpose of this patch is to internalize the sysfs interface code
among the various counter drivers into a shared module. Counter drivers
pass and take data natively (i.e. u8, u64, etc.) and the shared counter
module handles the translation between the sysfs interface. This
gurantees a standard userspace interface for all counter drivers, and
helps generalize the Generic Counter driver ABI in order to support the
Generic Counter chrdev interface (introduced in a subsequent patch)
without significant changes to the existing counter drivers.
A high-level view of how a count value is passed down from a counter
driver is exemplified by the following:
----------------------
/ Counter device \
+----------------------+
| Count register: 0x28 |
+----------------------+
|
-----------------
/ raw count data /
-----------------
|
V
+----------------------------+
| Counter device driver |----------+
+----------------------------+ |
| Processes data from device | -------------------
|----------------------------| / driver callbacks /
| Type: unsigned long | -------------------
| Value: 42 | |
+----------------------------+ |
| |
---------------- |
/ unsigned long / |
---------------- |
| |
| V
| +----------------------+
| | Counter core |
| +----------------------+
| | Routes device driver |
| | callbacks to the |
| | userspace interfaces |
| +----------------------+
| |
| -------------------
| / driver callbacks /
| -------------------
| |
+-------+ |
| |
| +---------------+
| |
V |
+--------------------+ |
| Counter sysfs |<-+
+--------------------+
| Translates to the |
| standard Counter |
| sysfs output |
|--------------------|
| Type: const char * |
| Value: "42" |
+--------------------+
|
---------------
/ const char * /
---------------
|
V
+--------------------------------------------------+
| `/sys/bus/counter/devices/counterX/countY/count` |
+--------------------------------------------------+
\ Count: "42" /
--------------------------------------------------
There are three primary components involved:
Counter device driver
---------------------
Communicates with the hardware device to read/write data; e.g.
counter drivers for 104-quad-8, stm32-timer, etc.
Counter core
------------
Registers the counter device driver to the system so that the
respective callbacks are called during userspace interaction
Counter sysfs
-------------
Translates counter data to the standard Counter sysfs interface
format and vice versa
Driver ABI
==========
This reimplementation entails several changes to the driver ABI. In
particular, the device driver callbacks are now expected to handle
standard C datatypes rather than translating the sysfs I/O directly.
To that end, the struct counter_data structure is introduced to
establish counter extensions for Signals, Synapses, and Counts.
The "type" member specifies the type of high-level data (e.g. BOOL,
COUNT_DIRECTION, etc.) handled by this extension. The "*_read" and
"*_write" members can then be set by the counter device driver with
callbacks to handle that data using native C data types (i.e. u8, u64,
etc.).
Convenience macros such as COUNTER_DATA_COUNT_U64 are provided for use
by driver authors. In particular, driver authors are expected to use
the provided macros for standard Counter subsystem attributes in order
to maintain a consistent interface for userspace. For example, a counter
device driver may define several standard attributes like so:
struct counter_data count_ext[] = {
COUNTER_DATA_DIRECTION(count_direction_read),
COUNTER_DATA_ENABLE(count_enable_read, count_enable_write),
COUNTER_DATA_CEILING(count_ceiling_read, count_ceiling_write),
};
This makes it simple to see, add, and modify the attributes that are
supported by this driver ("direction", "enable", and "ceiling") and to
maintain this code without getting lost in a web of struct braces.
Callbacks must match the function type expected for the respective
component or extension. These function types are defined in the struct
counter_data structure as the "*_read" and "*_write" union members.
The corresponding callback prototypes for the extensions above would be:
int count_direction_read(struct counter_device *counter,
struct counter_count *count, u8 *direction);
int count_enable_read(struct counter_device *counter,
struct counter_count *count, u8 *enable);
int count_enable_write(struct counter_device *counter,
struct counter_count *count, u8 enable);
int count_ceiling_read(struct counter_device *counter,
struct counter_count *count, u64 *ceiling);
int count_ceiling_write(struct counter_device *counter,
struct counter_count *count, u64 ceiling);
In this way, driver authors no longer need to mess with sysfs strings
and are instead able to focus on what they actually care about doing --
getting data to/from the devices -- while the Generic Counter interface
handles the translation of that data for them between the various
userspace interfaces (e.g. sysfs and chardev).
Architecture
============
Counter device registration is the same as before: drivers populate a
struct counter_device with components and callbacks, then pass the
structure to the devm_counter_register function. However, what's
different now is how the Counter subsystem code handles this
registration internally.
Whereas before callbacks would interact directly with sysfs data, this
interaction is now abstracted and instead callbacks interact with native
C data types. The counter_data structure forms the basis for Counter
extentions.
The counter-sysfs.c file contains the code to parse through the
counter_device structure and register the requested components and
extensions. Attributes are created and populated based on type, with
respective translation functions to handle the mapping between sysfs and
the counter driver callbacks.
The translation performed for each attribute is straightforward: the
attribute type and data is parsed from the counter_attribute structure,
the respective counter driver read/write callback is called, and sysfs
I/O is handled before or after the driver read/write function is called.
Cc: Syed Nayyar Waris <syednwaris@gmail.com>
Cc: Patrick Havelange <patrick.havelange@essensium.com>
Cc: Fabrice Gasnier <fabrice.gasnier@st.com>
Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com>
Cc: Alexandre Torgue <alexandre.torgue@st.com>
Cc: David Lechner <david@lechnology.com>
Signed-off-by: William Breathitt Gray <vilhelm.gray@gmail.com>
---
MAINTAINERS | 2 +-
drivers/counter/104-quad-8.c | 474 ++++-----
drivers/counter/Makefile | 1 +
drivers/counter/counter-common.h | 15 +
drivers/counter/counter-core.c | 157 +++
drivers/counter/counter-sysfs.c | 851 +++++++++++++++
drivers/counter/counter-sysfs.h | 14 +
drivers/counter/counter.c | 1496 ---------------------------
drivers/counter/ftm-quaddec.c | 59 +-
drivers/counter/stm32-lptimer-cnt.c | 161 +--
drivers/counter/stm32-timer-cnt.c | 139 +--
drivers/counter/ti-eqep.c | 211 ++--
include/linux/counter.h | 618 +++++------
include/linux/counter_enum.h | 45 -
include/uapi/linux/counter-types.h | 34 +
15 files changed, 1799 insertions(+), 2478 deletions(-)
create mode 100644 drivers/counter/counter-common.h
create mode 100644 drivers/counter/counter-core.c
create mode 100644 drivers/counter/counter-sysfs.c
create mode 100644 drivers/counter/counter-sysfs.h
delete mode 100644 drivers/counter/counter.c
delete mode 100644 include/linux/counter_enum.h
create mode 100644 include/uapi/linux/counter-types.h
diff --git a/MAINTAINERS b/MAINTAINERS
index 510fa7f7c756..7ea12db794be 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -4413,7 +4413,7 @@ F: Documentation/ABI/testing/sysfs-bus-counter*
F: Documentation/driver-api/generic-counter.rst
F: drivers/counter/
F: include/linux/counter.h
-F: include/linux/counter_enum.h
+F: include/uapi/linux/counter-types.h
CPMAC ETHERNET DRIVER
M: Florian Fainelli <f.fainelli@gmail.com>
diff --git a/drivers/counter/104-quad-8.c b/drivers/counter/104-quad-8.c
index 69fd34fe2749..c333d7507685 100644
--- a/drivers/counter/104-quad-8.c
+++ b/drivers/counter/104-quad-8.c
@@ -621,7 +621,7 @@ static const struct iio_chan_spec quad8_channels[] = {
};
static int quad8_signal_read(struct counter_device *counter,
- struct counter_signal *signal, enum counter_signal_value *val)
+ struct counter_signal *signal, u8 *val)
{
const struct quad8_iio *const priv = counter->priv;
unsigned int state;
@@ -639,7 +639,7 @@ static int quad8_signal_read(struct counter_device *counter,
}
static int quad8_count_read(struct counter_device *counter,
- struct counter_count *count, unsigned long *val)
+ struct counter_count *count, u64 *val)
{
struct quad8_iio *const priv = counter->priv;
const int base_offset = priv->base + 2 * count->id;
@@ -670,7 +670,7 @@ static int quad8_count_read(struct counter_device *counter,
}
static int quad8_count_write(struct counter_device *counter,
- struct counter_count *count, unsigned long val)
+ struct counter_count *count, u64 val)
{
struct quad8_iio *const priv = counter->priv;
const int base_offset = priv->base + 2 * count->id;
@@ -710,22 +710,16 @@ static int quad8_count_write(struct counter_device *counter,
return 0;
}
-enum quad8_count_function {
- QUAD8_COUNT_FUNCTION_PULSE_DIRECTION = 0,
- QUAD8_COUNT_FUNCTION_QUADRATURE_X1,
- QUAD8_COUNT_FUNCTION_QUADRATURE_X2,
- QUAD8_COUNT_FUNCTION_QUADRATURE_X4
-};
-static enum counter_count_function quad8_count_functions_list[] = {
- [QUAD8_COUNT_FUNCTION_PULSE_DIRECTION] = COUNTER_COUNT_FUNCTION_PULSE_DIRECTION,
- [QUAD8_COUNT_FUNCTION_QUADRATURE_X1] = COUNTER_COUNT_FUNCTION_QUADRATURE_X1_A,
- [QUAD8_COUNT_FUNCTION_QUADRATURE_X2] = COUNTER_COUNT_FUNCTION_QUADRATURE_X2_A,
- [QUAD8_COUNT_FUNCTION_QUADRATURE_X4] = COUNTER_COUNT_FUNCTION_QUADRATURE_X4
+static const u8 quad8_count_functions_list[] = {
+ COUNTER_COUNT_FUNCTION_PULSE_DIRECTION,
+ COUNTER_COUNT_FUNCTION_QUADRATURE_X1_A,
+ COUNTER_COUNT_FUNCTION_QUADRATURE_X2_A,
+ COUNTER_COUNT_FUNCTION_QUADRATURE_X4,
};
-static int quad8_function_get(struct counter_device *counter,
- struct counter_count *count, size_t *function)
+static int quad8_function_read(struct counter_device *counter,
+ struct counter_count *count, u8 *function)
{
struct quad8_iio *const priv = counter->priv;
const int id = count->id;
@@ -735,25 +729,25 @@ static int quad8_function_get(struct counter_device *counter,
if (priv->quadrature_mode[id])
switch (priv->quadrature_scale[id]) {
case 0:
- *function = QUAD8_COUNT_FUNCTION_QUADRATURE_X1;
+ *function = COUNTER_COUNT_FUNCTION_QUADRATURE_X1_A;
break;
case 1:
- *function = QUAD8_COUNT_FUNCTION_QUADRATURE_X2;
+ *function = COUNTER_COUNT_FUNCTION_QUADRATURE_X2_A;
break;
case 2:
- *function = QUAD8_COUNT_FUNCTION_QUADRATURE_X4;
+ *function = COUNTER_COUNT_FUNCTION_QUADRATURE_X4;
break;
}
else
- *function = QUAD8_COUNT_FUNCTION_PULSE_DIRECTION;
+ *function = COUNTER_COUNT_FUNCTION_PULSE_DIRECTION;
mutex_unlock(&priv->lock);
return 0;
}
-static int quad8_function_set(struct counter_device *counter,
- struct counter_count *count, size_t function)
+static int quad8_function_write(struct counter_device *counter,
+ struct counter_count *count, u8 function)
{
struct quad8_iio *const priv = counter->priv;
const int id = count->id;
@@ -769,7 +763,7 @@ static int quad8_function_set(struct counter_device *counter,
mode_cfg = priv->count_mode[id] << 1;
idr_cfg = priv->index_polarity[id] << 1;
- if (function == QUAD8_COUNT_FUNCTION_PULSE_DIRECTION) {
+ if (function == COUNTER_COUNT_FUNCTION_PULSE_DIRECTION) {
*quadrature_mode = 0;
/* Quadrature scaling only available in quadrature mode */
@@ -785,15 +779,15 @@ static int quad8_function_set(struct counter_device *counter,
*quadrature_mode = 1;
switch (function) {
- case QUAD8_COUNT_FUNCTION_QUADRATURE_X1:
+ case COUNTER_COUNT_FUNCTION_QUADRATURE_X1_A:
*scale = 0;
mode_cfg |= QUAD8_CMR_QUADRATURE_X1;
break;
- case QUAD8_COUNT_FUNCTION_QUADRATURE_X2:
+ case COUNTER_COUNT_FUNCTION_QUADRATURE_X2_A:
*scale = 1;
mode_cfg |= QUAD8_CMR_QUADRATURE_X2;
break;
- case QUAD8_COUNT_FUNCTION_QUADRATURE_X4:
+ case COUNTER_COUNT_FUNCTION_QUADRATURE_X4:
*scale = 2;
mode_cfg |= QUAD8_CMR_QUADRATURE_X4;
break;
@@ -808,8 +802,8 @@ static int quad8_function_set(struct counter_device *counter,
return 0;
}
-static void quad8_direction_get(struct counter_device *counter,
- struct counter_count *count, enum counter_count_direction *direction)
+static int quad8_direction_read(struct counter_device *counter,
+ struct counter_count *count, u8 *direction)
{
const struct quad8_iio *const priv = counter->priv;
unsigned int ud_flag;
@@ -820,93 +814,82 @@ static void quad8_direction_get(struct counter_device *counter,
*direction = (ud_flag) ? COUNTER_COUNT_DIRECTION_FORWARD :
COUNTER_COUNT_DIRECTION_BACKWARD;
-}
-enum quad8_synapse_action {
- QUAD8_SYNAPSE_ACTION_NONE = 0,
- QUAD8_SYNAPSE_ACTION_RISING_EDGE,
- QUAD8_SYNAPSE_ACTION_FALLING_EDGE,
- QUAD8_SYNAPSE_ACTION_BOTH_EDGES
-};
+ return 0;
+}
-static enum counter_synapse_action quad8_index_actions_list[] = {
- [QUAD8_SYNAPSE_ACTION_NONE] = COUNTER_SYNAPSE_ACTION_NONE,
- [QUAD8_SYNAPSE_ACTION_RISING_EDGE] = COUNTER_SYNAPSE_ACTION_RISING_EDGE
+static const u8 quad8_index_actions_list[] = {
+ COUNTER_SYNAPSE_ACTION_NONE,
+ COUNTER_SYNAPSE_ACTION_RISING_EDGE,
};
-static enum counter_synapse_action quad8_synapse_actions_list[] = {
- [QUAD8_SYNAPSE_ACTION_NONE] = COUNTER_SYNAPSE_ACTION_NONE,
- [QUAD8_SYNAPSE_ACTION_RISING_EDGE] = COUNTER_SYNAPSE_ACTION_RISING_EDGE,
- [QUAD8_SYNAPSE_ACTION_FALLING_EDGE] = COUNTER_SYNAPSE_ACTION_FALLING_EDGE,
- [QUAD8_SYNAPSE_ACTION_BOTH_EDGES] = COUNTER_SYNAPSE_ACTION_BOTH_EDGES
+static const u8 quad8_synapse_actions_list[] = {
+ COUNTER_SYNAPSE_ACTION_NONE,
+ COUNTER_SYNAPSE_ACTION_RISING_EDGE,
+ COUNTER_SYNAPSE_ACTION_FALLING_EDGE,
+ COUNTER_SYNAPSE_ACTION_BOTH_EDGES,
};
-static int quad8_action_get(struct counter_device *counter,
- struct counter_count *count, struct counter_synapse *synapse,
- size_t *action)
+static int quad8_action_read(struct counter_device *counter,
+ struct counter_count *count,
+ struct counter_synapse *synapse, u8 *action)
{
struct quad8_iio *const priv = counter->priv;
int err;
- size_t function = 0;
+ u8 function;
const size_t signal_a_id = count->synapses[0].signal->id;
- enum counter_count_direction direction;
+ u8 direction;
/* Handle Index signals */
if (synapse->signal->id >= 16) {
if (priv->preset_enable[count->id])
- *action = QUAD8_SYNAPSE_ACTION_RISING_EDGE;
+ *action = COUNTER_SYNAPSE_ACTION_RISING_EDGE;
else
- *action = QUAD8_SYNAPSE_ACTION_NONE;
+ *action = COUNTER_SYNAPSE_ACTION_NONE;
return 0;
}
- err = quad8_function_get(counter, count, &function);
+ err = quad8_function_read(counter, count, &function);
if (err)
return err;
/* Default action mode */
- *action = QUAD8_SYNAPSE_ACTION_NONE;
+ *action = COUNTER_SYNAPSE_ACTION_NONE;
/* Determine action mode based on current count function mode */
switch (function) {
- case QUAD8_COUNT_FUNCTION_PULSE_DIRECTION:
+ case COUNTER_COUNT_FUNCTION_PULSE_DIRECTION:
if (synapse->signal->id == signal_a_id)
- *action = QUAD8_SYNAPSE_ACTION_RISING_EDGE;
+ *action = COUNTER_SYNAPSE_ACTION_RISING_EDGE;
break;
- case QUAD8_COUNT_FUNCTION_QUADRATURE_X1:
+ case COUNTER_COUNT_FUNCTION_QUADRATURE_X1_A:
if (synapse->signal->id == signal_a_id) {
- quad8_direction_get(counter, count, &direction);
+ err = quad8_direction_read(counter, count, &direction);
+ if (err)
+ return err;
if (direction == COUNTER_COUNT_DIRECTION_FORWARD)
- *action = QUAD8_SYNAPSE_ACTION_RISING_EDGE;
+ *action = COUNTER_SYNAPSE_ACTION_RISING_EDGE;
else
- *action = QUAD8_SYNAPSE_ACTION_FALLING_EDGE;
+ *action = COUNTER_SYNAPSE_ACTION_FALLING_EDGE;
}
break;
- case QUAD8_COUNT_FUNCTION_QUADRATURE_X2:
+ case COUNTER_COUNT_FUNCTION_QUADRATURE_X2_A:
if (synapse->signal->id == signal_a_id)
- *action = QUAD8_SYNAPSE_ACTION_BOTH_EDGES;
+ *action = COUNTER_SYNAPSE_ACTION_BOTH_EDGES;
break;
- case QUAD8_COUNT_FUNCTION_QUADRATURE_X4:
- *action = QUAD8_SYNAPSE_ACTION_BOTH_EDGES;
+ case COUNTER_COUNT_FUNCTION_QUADRATURE_X4:
+ *action = COUNTER_SYNAPSE_ACTION_BOTH_EDGES;
break;
}
return 0;
}
-static const struct counter_ops quad8_ops = {
- .signal_read = quad8_signal_read,
- .count_read = quad8_count_read,
- .count_write = quad8_count_write,
- .function_get = quad8_function_get,
- .function_set = quad8_function_set,
- .action_get = quad8_action_get
-};
-
static int quad8_index_polarity_get(struct counter_device *counter,
- struct counter_signal *signal, size_t *index_polarity)
+ struct counter_signal *signal,
+ u8 *index_polarity)
{
const struct quad8_iio *const priv = counter->priv;
const size_t channel_id = signal->id - 16;
@@ -917,20 +900,20 @@ static int quad8_index_polarity_get(struct counter_device *counter,
}
static int quad8_index_polarity_set(struct counter_device *counter,
- struct counter_signal *signal, size_t index_polarity)
+ struct counter_signal *signal,
+ u8 index_polarity)
{
struct quad8_iio *const priv = counter->priv;
const size_t channel_id = signal->id - 16;
const int base_offset = priv->base + 2 * channel_id + 1;
- unsigned int idr_cfg = index_polarity << 1;
+ unsigned int idr_cfg;
mutex_lock(&priv->lock);
- idr_cfg |= priv->synchronous_mode[channel_id];
-
priv->index_polarity[channel_id] = index_polarity;
/* Load Index Control configuration to Index Control Register */
+ idr_cfg = priv->synchronous_mode[channel_id] | index_polarity << 1;
outb(QUAD8_CTR_IDR | idr_cfg, base_offset);
mutex_unlock(&priv->lock);
@@ -938,15 +921,9 @@ static int quad8_index_polarity_set(struct counter_device *counter,
return 0;
}
-static struct counter_signal_enum_ext quad8_index_pol_enum = {
- .items = quad8_index_polarity_modes,
- .num_items = ARRAY_SIZE(quad8_index_polarity_modes),
- .get = quad8_index_polarity_get,
- .set = quad8_index_polarity_set
-};
-
static int quad8_synchronous_mode_get(struct counter_device *counter,
- struct counter_signal *signal, size_t *synchronous_mode)
+ struct counter_signal *signal,
+ u8 *synchronous_mode)
{
const struct quad8_iio *const priv = counter->priv;
const size_t channel_id = signal->id - 16;
@@ -957,17 +934,16 @@ static int quad8_synchronous_mode_get(struct counter_device *counter,
}
static int quad8_synchronous_mode_set(struct counter_device *counter,
- struct counter_signal *signal, size_t synchronous_mode)
+ struct counter_signal *signal,
+ u8 synchronous_mode)
{
struct quad8_iio *const priv = counter->priv;
const size_t channel_id = signal->id - 16;
const int base_offset = priv->base + 2 * channel_id + 1;
- unsigned int idr_cfg = synchronous_mode;
+ unsigned int idr_cfg;
mutex_lock(&priv->lock);
- idr_cfg |= priv->index_polarity[channel_id] << 1;
-
/* Index function must be non-synchronous in non-quadrature mode */
if (synchronous_mode && !priv->quadrature_mode[channel_id]) {
mutex_unlock(&priv->lock);
@@ -977,6 +953,7 @@ static int quad8_synchronous_mode_set(struct counter_device *counter,
priv->synchronous_mode[channel_id] = synchronous_mode;
/* Load Index Control configuration to Index Control Register */
+ idr_cfg = synchronous_mode | priv->index_polarity[channel_id] << 1;
outb(QUAD8_CTR_IDR | idr_cfg, base_offset);
mutex_unlock(&priv->lock);
@@ -984,22 +961,17 @@ static int quad8_synchronous_mode_set(struct counter_device *counter,
return 0;
}
-static struct counter_signal_enum_ext quad8_syn_mode_enum = {
- .items = quad8_synchronous_modes,
- .num_items = ARRAY_SIZE(quad8_synchronous_modes),
- .get = quad8_synchronous_mode_get,
- .set = quad8_synchronous_mode_set
-};
-
-static ssize_t quad8_count_floor_read(struct counter_device *counter,
- struct counter_count *count, void *private, char *buf)
+static int quad8_count_floor_read(struct counter_device *counter,
+ struct counter_count *count, u64 *floor)
{
/* Only a floor of 0 is supported */
- return sprintf(buf, "0\n");
+ *floor = 0;
+
+ return 0;
}
-static int quad8_count_mode_get(struct counter_device *counter,
- struct counter_count *count, size_t *cnt_mode)
+static int quad8_count_mode_read(struct counter_device *counter,
+ struct counter_count *count, u8 *cnt_mode)
{
const struct quad8_iio *const priv = counter->priv;
@@ -1022,35 +994,36 @@ static int quad8_count_mode_get(struct counter_device *counter,
return 0;
}
-static int quad8_count_mode_set(struct counter_device *counter,
- struct counter_count *count, size_t cnt_mode)
+static int quad8_count_mode_write(struct counter_device *counter,
+ struct counter_count *count, u8 cnt_mode)
{
struct quad8_iio *const priv = counter->priv;
+ unsigned int count_mode;
unsigned int mode_cfg;
const int base_offset = priv->base + 2 * count->id + 1;
/* Map Generic Counter count mode to 104-QUAD-8 count mode */
switch (cnt_mode) {
case COUNTER_COUNT_MODE_NORMAL:
- cnt_mode = 0;
+ count_mode = 0;
break;
case COUNTER_COUNT_MODE_RANGE_LIMIT:
- cnt_mode = 1;
+ count_mode = 1;
break;
case COUNTER_COUNT_MODE_NON_RECYCLE:
- cnt_mode = 2;
+ count_mode = 2;
break;
case COUNTER_COUNT_MODE_MODULO_N:
- cnt_mode = 3;
+ count_mode = 3;
break;
}
mutex_lock(&priv->lock);
- priv->count_mode[count->id] = cnt_mode;
+ priv->count_mode[count->id] = count_mode;
/* Set count mode configuration value */
- mode_cfg = cnt_mode << 1;
+ mode_cfg = count_mode << 1;
/* Add quadrature mode configuration */
if (priv->quadrature_mode[count->id])
@@ -1064,60 +1037,39 @@ static int quad8_count_mode_set(struct counter_device *counter,
return 0;
}
-static struct counter_count_enum_ext quad8_cnt_mode_enum = {
- .items = counter_count_mode_str,
- .num_items = ARRAY_SIZE(counter_count_mode_str),
- .get = quad8_count_mode_get,
- .set = quad8_count_mode_set
-};
-
-static ssize_t quad8_count_direction_read(struct counter_device *counter,
- struct counter_count *count, void *priv, char *buf)
-{
- enum counter_count_direction dir;
-
- quad8_direction_get(counter, count, &dir);
-
- return sprintf(buf, "%s\n", counter_count_direction_str[dir]);
-}
-
-static ssize_t quad8_count_enable_read(struct counter_device *counter,
- struct counter_count *count, void *private, char *buf)
+static int quad8_count_enable_read(struct counter_device *counter,
+ struct counter_count *count, u8 *enable)
{
const struct quad8_iio *const priv = counter->priv;
- return sprintf(buf, "%u\n", priv->ab_enable[count->id]);
+ *enable = priv->ab_enable[count->id];
+
+ return 0;
}
-static ssize_t quad8_count_enable_write(struct counter_device *counter,
- struct counter_count *count, void *private, const char *buf, size_t len)
+static int quad8_count_enable_write(struct counter_device *counter,
+ struct counter_count *count, u8 enable)
{
struct quad8_iio *const priv = counter->priv;
const int base_offset = priv->base + 2 * count->id;
- int err;
- bool ab_enable;
unsigned int ior_cfg;
- err = kstrtobool(buf, &ab_enable);
- if (err)
- return err;
-
mutex_lock(&priv->lock);
- priv->ab_enable[count->id] = ab_enable;
+ priv->ab_enable[count->id] = enable;
- ior_cfg = ab_enable | priv->preset_enable[count->id] << 1;
+ ior_cfg = enable | priv->preset_enable[count->id] << 1;
/* Load I/O control configuration */
outb(QUAD8_CTR_IOR | ior_cfg, base_offset + 1);
mutex_unlock(&priv->lock);
- return len;
+ return 0;
}
static int quad8_error_noise_get(struct counter_device *counter,
- struct counter_count *count, size_t *noise_error)
+ struct counter_count *count, u8 *noise_error)
{
const struct quad8_iio *const priv = counter->priv;
const int base_offset = priv->base + 2 * count->id + 1;
@@ -1127,22 +1079,18 @@ static int quad8_error_noise_get(struct counter_device *counter,
return 0;
}
-static struct counter_count_enum_ext quad8_error_noise_enum = {
- .items = quad8_noise_error_states,
- .num_items = ARRAY_SIZE(quad8_noise_error_states),
- .get = quad8_error_noise_get
-};
-
-static ssize_t quad8_count_preset_read(struct counter_device *counter,
- struct counter_count *count, void *private, char *buf)
+static int quad8_count_preset_read(struct counter_device *counter,
+ struct counter_count *count, u64 *preset)
{
const struct quad8_iio *const priv = counter->priv;
- return sprintf(buf, "%u\n", priv->preset[count->id]);
+ *preset = priv->preset[count->id];
+
+ return 0;
}
-static void quad8_preset_register_set(struct quad8_iio *quad8iio, int id,
- unsigned int preset)
+static void quad8_preset_register_set(struct quad8_iio *const quad8iio,
+ const int id, const u64 preset)
{
const unsigned int base_offset = quad8iio->base + 2 * id;
int i;
@@ -1157,16 +1105,10 @@ static void quad8_preset_register_set(struct quad8_iio *quad8iio, int id,
outb(preset >> (8 * i), base_offset);
}
-static ssize_t quad8_count_preset_write(struct counter_device *counter,
- struct counter_count *count, void *private, const char *buf, size_t len)
+static int quad8_count_preset_write(struct counter_device *counter,
+ struct counter_count *count, u64 preset)
{
struct quad8_iio *const priv = counter->priv;
- unsigned int preset;
- int ret;
-
- ret = kstrtouint(buf, 0, &preset);
- if (ret)
- return ret;
/* Only 24-bit values are supported */
if (preset > 0xFFFFFF)
@@ -1178,11 +1120,11 @@ static ssize_t quad8_count_preset_write(struct counter_device *counter,
mutex_unlock(&priv->lock);
- return len;
+ return 0;
}
-static ssize_t quad8_count_ceiling_read(struct counter_device *counter,
- struct counter_count *count, void *private, char *buf)
+static int quad8_count_ceiling_read(struct counter_device *counter,
+ struct counter_count *count, u64 *ceiling)
{
struct quad8_iio *const priv = counter->priv;
@@ -1193,25 +1135,21 @@ static ssize_t quad8_count_ceiling_read(struct counter_device *counter,
case 1:
case 3:
mutex_unlock(&priv->lock);
- return sprintf(buf, "%u\n", priv->preset[count->id]);
+ return quad8_count_preset_read(counter, count, ceiling);
}
mutex_unlock(&priv->lock);
/* By default 0x1FFFFFF (25 bits unsigned) is maximum count */
- return sprintf(buf, "33554431\n");
+ *ceiling = 0x1FFFFFF;
+
+ return 0;
}
-static ssize_t quad8_count_ceiling_write(struct counter_device *counter,
- struct counter_count *count, void *private, const char *buf, size_t len)
+static int quad8_count_ceiling_write(struct counter_device *counter,
+ struct counter_count *count, u64 ceiling)
{
struct quad8_iio *const priv = counter->priv;
- unsigned int ceiling;
- int ret;
-
- ret = kstrtouint(buf, 0, &ceiling);
- if (ret)
- return ret;
/* Only 24-bit values are supported */
if (ceiling > 0xFFFFFF)
@@ -1223,36 +1161,33 @@ static ssize_t quad8_count_ceiling_write(struct counter_device *counter,
switch (priv->count_mode[count->id]) {
case 1:
case 3:
- quad8_preset_register_set(priv, count->id, ceiling);
- break;
+ return quad8_count_preset_write(counter, count, ceiling);
}
mutex_unlock(&priv->lock);
- return len;
+ return -EINVAL;
}
-static ssize_t quad8_count_preset_enable_read(struct counter_device *counter,
- struct counter_count *count, void *private, char *buf)
+static int quad8_count_preset_enable_read(struct counter_device *counter,
+ struct counter_count *count,
+ u8 *preset_enable)
{
const struct quad8_iio *const priv = counter->priv;
- return sprintf(buf, "%u\n", !priv->preset_enable[count->id]);
+ *preset_enable = !priv->preset_enable[count->id];
+
+ return 0;
}
-static ssize_t quad8_count_preset_enable_write(struct counter_device *counter,
- struct counter_count *count, void *private, const char *buf, size_t len)
+static int quad8_count_preset_enable_write(struct counter_device *counter,
+ struct counter_count *count,
+ u8 preset_enable)
{
struct quad8_iio *const priv = counter->priv;
const int base_offset = priv->base + 2 * count->id + 1;
- bool preset_enable;
- int ret;
unsigned int ior_cfg;
- ret = kstrtobool(buf, &preset_enable);
- if (ret)
- return ret;
-
/* Preset enable is active low in Input/Output Control register */
preset_enable = !preset_enable;
@@ -1260,25 +1195,24 @@ static ssize_t quad8_count_preset_enable_write(struct counter_device *counter,
priv->preset_enable[count->id] = preset_enable;
- ior_cfg = priv->ab_enable[count->id] | (unsigned int)preset_enable << 1;
+ ior_cfg = priv->ab_enable[count->id] | preset_enable << 1;
/* Load I/O control configuration to Input / Output Control Register */
outb(QUAD8_CTR_IOR | ior_cfg, base_offset);
mutex_unlock(&priv->lock);
- return len;
+ return 0;
}
-static ssize_t quad8_signal_cable_fault_read(struct counter_device *counter,
- struct counter_signal *signal,
- void *private, char *buf)
+static int quad8_signal_cable_fault_read(struct counter_device *counter,
+ struct counter_signal *signal,
+ u8 *cable_fault)
{
const struct quad8_iio *const priv = counter->priv;
const size_t channel_id = signal->id / 2;
const bool disabled = !(priv->cable_fault_enable & BIT(channel_id));
unsigned int status;
- unsigned int fault;
if (disabled)
return -EINVAL;
@@ -1287,36 +1221,31 @@ static ssize_t quad8_signal_cable_fault_read(struct counter_device *counter,
status = inb(priv->base + QUAD8_DIFF_ENCODER_CABLE_STATUS);
/* Mask respective channel and invert logic */
- fault = !(status & BIT(channel_id));
+ *cable_fault = !(status & BIT(channel_id));
- return sprintf(buf, "%u\n", fault);
+ return 0;
}
-static ssize_t quad8_signal_cable_fault_enable_read(
- struct counter_device *counter, struct counter_signal *signal,
- void *private, char *buf)
+static int quad8_signal_cable_fault_enable_read(struct counter_device *counter,
+ struct counter_signal *signal,
+ u8 *enable)
{
const struct quad8_iio *const priv = counter->priv;
const size_t channel_id = signal->id / 2;
- const unsigned int enb = !!(priv->cable_fault_enable & BIT(channel_id));
- return sprintf(buf, "%u\n", enb);
+ *enable = !!(priv->cable_fault_enable & BIT(channel_id));
+
+ return 0;
}
-static ssize_t quad8_signal_cable_fault_enable_write(
- struct counter_device *counter, struct counter_signal *signal,
- void *private, const char *buf, size_t len)
+static int quad8_signal_cable_fault_enable_write(struct counter_device *counter,
+ struct counter_signal *signal,
+ u8 enable)
{
struct quad8_iio *const priv = counter->priv;
const size_t channel_id = signal->id / 2;
- bool enable;
- int ret;
unsigned int cable_fault_enable;
- ret = kstrtobool(buf, &enable);
- if (ret)
- return ret;
-
if (enable)
priv->cable_fault_enable |= BIT(channel_id);
else
@@ -1327,31 +1256,27 @@ static ssize_t quad8_signal_cable_fault_enable_write(
outb(cable_fault_enable, priv->base + QUAD8_DIFF_ENCODER_CABLE_STATUS);
- return len;
+ return 0;
}
-static ssize_t quad8_signal_fck_prescaler_read(struct counter_device *counter,
- struct counter_signal *signal, void *private, char *buf)
+static int quad8_signal_fck_prescaler_read(struct counter_device *counter,
+ struct counter_signal *signal,
+ u8 *prescaler)
{
const struct quad8_iio *const priv = counter->priv;
- const size_t channel_id = signal->id / 2;
- return sprintf(buf, "%u\n", priv->fck_prescaler[channel_id]);
+ *prescaler = priv->fck_prescaler[signal->id / 2];
+
+ return 0;
}
-static ssize_t quad8_signal_fck_prescaler_write(struct counter_device *counter,
- struct counter_signal *signal, void *private, const char *buf,
- size_t len)
+static int quad8_signal_fck_prescaler_write(struct counter_device *counter,
+ struct counter_signal *signal,
+ u8 prescaler)
{
struct quad8_iio *const priv = counter->priv;
const size_t channel_id = signal->id / 2;
const int base_offset = priv->base + 2 * channel_id;
- u8 prescaler;
- int ret;
-
- ret = kstrtou8(buf, 0, &prescaler);
- if (ret)
- return ret;
priv->fck_prescaler[channel_id] = prescaler;
@@ -1363,31 +1288,30 @@ static ssize_t quad8_signal_fck_prescaler_write(struct counter_device *counter,
outb(QUAD8_CTR_RLD | QUAD8_RLD_RESET_BP | QUAD8_RLD_PRESET_PSC,
base_offset + 1);
- return len;
+ return 0;
}
-static const struct counter_signal_ext quad8_signal_ext[] = {
- {
- .name = "cable_fault",
- .read = quad8_signal_cable_fault_read
- },
- {
- .name = "cable_fault_enable",
- .read = quad8_signal_cable_fault_enable_read,
- .write = quad8_signal_cable_fault_enable_write
- },
- {
- .name = "filter_clock_prescaler",
- .read = quad8_signal_fck_prescaler_read,
- .write = quad8_signal_fck_prescaler_write
- }
+static struct counter_data quad8_signal_ext[] = {
+ COUNTER_DATA_SIGNAL_BOOL("cable_fault", quad8_signal_cable_fault_read,
+ NULL),
+ COUNTER_DATA_SIGNAL_BOOL("cable_fault_enable",
+ quad8_signal_cable_fault_enable_read,
+ quad8_signal_cable_fault_enable_write),
+ COUNTER_DATA_SIGNAL_U8("filter_clock_prescaler",
+ quad8_signal_fck_prescaler_read,
+ quad8_signal_fck_prescaler_write)
};
-static const struct counter_signal_ext quad8_index_ext[] = {
- COUNTER_SIGNAL_ENUM("index_polarity", &quad8_index_pol_enum),
- COUNTER_SIGNAL_ENUM_AVAILABLE("index_polarity", &quad8_index_pol_enum),
- COUNTER_SIGNAL_ENUM("synchronous_mode", &quad8_syn_mode_enum),
- COUNTER_SIGNAL_ENUM_AVAILABLE("synchronous_mode", &quad8_syn_mode_enum)
+static DEFINE_COUNTER_ENUM(quad8_index_pol_enum, quad8_index_polarity_modes);
+static DEFINE_COUNTER_ENUM(quad8_synch_mode_enum, quad8_synchronous_modes);
+
+static struct counter_data quad8_index_ext[] = {
+ COUNTER_DATA_SIGNAL_ENUM("index_polarity", quad8_index_polarity_get,
+ quad8_index_polarity_set,
+ quad8_index_pol_enum),
+ COUNTER_DATA_SIGNAL_ENUM("synchronous_mode", quad8_synchronous_mode_get,
+ quad8_synchronous_mode_set,
+ quad8_synch_mode_enum),
};
#define QUAD8_QUAD_SIGNAL(_id, _name) { \
@@ -1456,39 +1380,30 @@ static struct counter_synapse quad8_count_synapses[][3] = {
QUAD8_COUNT_SYNAPSES(6), QUAD8_COUNT_SYNAPSES(7)
};
-static const struct counter_count_ext quad8_count_ext[] = {
- {
- .name = "ceiling",
- .read = quad8_count_ceiling_read,
- .write = quad8_count_ceiling_write
- },
- {
- .name = "floor",
- .read = quad8_count_floor_read
- },
- COUNTER_COUNT_ENUM("count_mode", &quad8_cnt_mode_enum),
- COUNTER_COUNT_ENUM_AVAILABLE("count_mode", &quad8_cnt_mode_enum),
- {
- .name = "direction",
- .read = quad8_count_direction_read
- },
- {
- .name = "enable",
- .read = quad8_count_enable_read,
- .write = quad8_count_enable_write
- },
- COUNTER_COUNT_ENUM("error_noise", &quad8_error_noise_enum),
- COUNTER_COUNT_ENUM_AVAILABLE("error_noise", &quad8_error_noise_enum),
- {
- .name = "preset",
- .read = quad8_count_preset_read,
- .write = quad8_count_preset_write
- },
- {
- .name = "preset_enable",
- .read = quad8_count_preset_enable_read,
- .write = quad8_count_preset_enable_write
- }
+static const u8 quad8_cnt_modes[] = {
+ COUNTER_COUNT_MODE_NORMAL,
+ COUNTER_COUNT_MODE_RANGE_LIMIT,
+ COUNTER_COUNT_MODE_NON_RECYCLE,
+ COUNTER_COUNT_MODE_MODULO_N,
+};
+
+static DEFINE_COUNTER_AVAILABLE(quad8_count_mode_available, quad8_cnt_modes);
+
+static DEFINE_COUNTER_ENUM(quad8_error_noise_enum, quad8_noise_error_states);
+
+static struct counter_data quad8_count_ext[] = {
+ COUNTER_DATA_CEILING(quad8_count_ceiling_read,
+ quad8_count_ceiling_write),
+ COUNTER_DATA_FLOOR(quad8_count_floor_read, NULL),
+ COUNTER_DATA_COUNT_MODE(quad8_count_mode_read, quad8_count_mode_write,
+ quad8_count_mode_available),
+ COUNTER_DATA_DIRECTION(quad8_direction_read),
+ COUNTER_DATA_ENABLE(quad8_count_enable_read, quad8_count_enable_write),
+ COUNTER_DATA_COUNT_ENUM("error_noise", quad8_error_noise_get, NULL,
+ quad8_error_noise_enum),
+ COUNTER_DATA_PRESET(quad8_count_preset_read, quad8_count_preset_write),
+ COUNTER_DATA_PRESET_ENABLE(quad8_count_preset_enable_read,
+ quad8_count_preset_enable_write),
};
#define QUAD8_COUNT(_id, _cntname) { \
@@ -1543,7 +1458,12 @@ static int quad8_probe(struct device *dev, unsigned int id)
quad8iio = iio_priv(indio_dev);
quad8iio->counter.name = dev_name(dev);
quad8iio->counter.parent = dev;
- quad8iio->counter.ops = &quad8_ops;
+ quad8iio->counter.signal_read = quad8_signal_read;
+ quad8iio->counter.count_read = quad8_count_read;
+ quad8iio->counter.count_write = quad8_count_write;
+ quad8iio->counter.function_read = quad8_function_read;
+ quad8iio->counter.function_write = quad8_function_write;
+ quad8iio->counter.action_read = quad8_action_read;
quad8iio->counter.counts = quad8_counts;
quad8iio->counter.num_counts = ARRAY_SIZE(quad8_counts);
quad8iio->counter.signals = quad8_signals;
diff --git a/drivers/counter/Makefile b/drivers/counter/Makefile
index 55142d1f4c43..f48e337cbd85 100644
--- a/drivers/counter/Makefile
+++ b/drivers/counter/Makefile
@@ -4,6 +4,7 @@
#
obj-$(CONFIG_COUNTER) += counter.o
+counter-y := counter-core.o counter-sysfs.o
obj-$(CONFIG_104_QUAD_8) += 104-quad-8.o
obj-$(CONFIG_STM32_TIMER_CNT) += stm32-timer-cnt.o
diff --git a/drivers/counter/counter-common.h b/drivers/counter/counter-common.h
new file mode 100644
index 000000000000..a3d0c8e53485
--- /dev/null
+++ b/drivers/counter/counter-common.h
@@ -0,0 +1,15 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Counter subsystem common structures
+ * Copyright (C) 2020 William Breathitt Gray
+ */
+#ifndef _COUNTER_COMMON_H_
+#define _COUNTER_COMMON_H_
+
+enum counter_owner_type {
+ COUNTER_OWNER_TYPE_DEVICE,
+ COUNTER_OWNER_TYPE_SIGNAL,
+ COUNTER_OWNER_TYPE_COUNT,
+};
+
+#endif /* _COUNTER_COMMON_H_ */
diff --git a/drivers/counter/counter-core.c b/drivers/counter/counter-core.c
new file mode 100644
index 000000000000..499664809c75
--- /dev/null
+++ b/drivers/counter/counter-core.c
@@ -0,0 +1,157 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Generic Counter interface
+ * Copyright (C) 2020 William Breathitt Gray
+ */
+#include <linux/counter.h>
+#include <linux/device.h>
+#include <linux/export.h>
+#include <linux/gfp.h>
+#include <linux/idr.h>
+#include <linux/init.h>
+#include <linux/module.h>
+
+#include "counter-sysfs.h"
+
+/* Provides a unique ID for each counter device */
+static DEFINE_IDA(counter_ida);
+
+static void counter_device_release(struct device *dev)
+{
+ struct counter_device *const counter = dev_get_drvdata(dev);
+
+ counter_sysfs_free(counter);
+ ida_simple_remove(&counter_ida, counter->id);
+}
+
+static struct device_type counter_device_type = {
+ .name = "counter_device",
+ .release = counter_device_release
+};
+
+static struct bus_type counter_bus_type = {
+ .name = "counter"
+};
+
+/**
+ * counter_register - register Counter to the system
+ * @counter: pointer to Counter to register
+ *
+ * This function registers a Counter to the system. A sysfs "counter" directory
+ * will be created and populated with sysfs attributes correlating with the
+ * Counter Signals, Synapses, and Counts respectively.
+ */
+int counter_register(struct counter_device *const counter)
+{
+ struct device *const dev = &counter->dev;
+ int err;
+
+ /* Acquire unique ID */
+ counter->id = ida_simple_get(&counter_ida, 0, 0, GFP_KERNEL);
+ if (counter->id < 0)
+ return counter->id;
+
+ /* Configure device structure for Counter */
+ dev->type = &counter_device_type;
+ dev->bus = &counter_bus_type;
+ if (counter->parent) {
+ dev->parent = counter->parent;
+ dev->of_node = counter->parent->of_node;
+ }
+ dev_set_name(dev, "counter%d", counter->id);
+ device_initialize(dev);
+ dev_set_drvdata(dev, counter);
+
+ /* Add Counter sysfs attributes */
+ err = counter_sysfs_add(counter);
+ if (err)
+ goto err_free_id;
+
+ /* Add device to system */
+ err = device_add(dev);
+ if (err)
+ goto err_free_sysfs;
+
+ return 0;
+
+err_free_sysfs:
+ counter_sysfs_free(counter);
+err_free_id:
+ ida_simple_remove(&counter_ida, counter->id);
+ return err;
+}
+EXPORT_SYMBOL_GPL(counter_register);
+
+/**
+ * counter_unregister - unregister Counter from the system
+ * @counter: pointer to Counter to unregister
+ *
+ * The Counter is unregistered from the system; all allocated memory is freed.
+ */
+void counter_unregister(struct counter_device *const counter)
+{
+ if (counter) {
+ device_del(&counter->dev);
+ counter_sysfs_free(counter);
+ }
+}
+EXPORT_SYMBOL_GPL(counter_unregister);
+
+static void devm_counter_unreg(struct device *dev, void *res)
+{
+ counter_unregister(*(struct counter_device **)res);
+}
+
+/**
+ * devm_counter_register - Resource-managed counter_register
+ * @dev: device to allocate counter_device for
+ * @counter: pointer to Counter to register
+ *
+ * Managed counter_register. The Counter registered with this function is
+ * automatically unregistered on driver detach. This function calls
+ * counter_register internally. Refer to that function for more information.
+ *
+ * If an Counter registered with this function needs to be unregistered
+ * separately, devm_counter_unregister must be used.
+ *
+ * RETURNS:
+ * 0 on success, negative error number on failure.
+ */
+int devm_counter_register(struct device *dev,
+ struct counter_device *const counter)
+{
+ struct counter_device **ptr;
+ int ret;
+
+ ptr = devres_alloc(devm_counter_unreg, sizeof(*ptr), GFP_KERNEL);
+ if (!ptr)
+ return -ENOMEM;
+
+ ret = counter_register(counter);
+ if (!ret) {
+ *ptr = counter;
+ devres_add(dev, ptr);
+ } else {
+ devres_free(ptr);
+ }
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(devm_counter_register);
+
+static int __init counter_init(void)
+{
+ return bus_register(&counter_bus_type);
+}
+
+static void __exit counter_exit(void)
+{
+ bus_unregister(&counter_bus_type);
+}
+
+subsys_initcall(counter_init);
+module_exit(counter_exit);
+
+MODULE_AUTHOR("William Breathitt Gray <vilhelm.gray@gmail.com>");
+MODULE_DESCRIPTION("Generic Counter interface");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/counter/counter-sysfs.c b/drivers/counter/counter-sysfs.c
new file mode 100644
index 000000000000..ca69e9d4e833
--- /dev/null
+++ b/drivers/counter/counter-sysfs.c
@@ -0,0 +1,851 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Generic Counter sysfs interface
+ * Copyright (C) 2020 William Breathitt Gray
+ */
+#include <linux/counter.h>
+#include <linux/device.h>
+#include <linux/err.h>
+#include <linux/gfp.h>
+#include <linux/kernel.h>
+#include <linux/list.h>
+#include <linux/slab.h>
+#include <linux/string.h>
+#include <linux/sysfs.h>
+#include <linux/types.h>
+
+#include "counter-common.h"
+#include "counter-sysfs.h"
+
+struct counter_attribute {
+ struct device_attribute dev_attr;
+ struct list_head l;
+
+ struct counter_data data;
+ enum counter_owner_type type;
+ void *owner;
+};
+
+#define to_counter_attribute(_dev_attr) \
+ container_of(_dev_attr, struct counter_attribute, dev_attr)
+
+static const char *const counter_count_function_str[] = {
+ [COUNTER_COUNT_FUNCTION_INCREASE] = "increase",
+ [COUNTER_COUNT_FUNCTION_DECREASE] = "decrease",
+ [COUNTER_COUNT_FUNCTION_PULSE_DIRECTION] = "pulse-direction",
+ [COUNTER_COUNT_FUNCTION_QUADRATURE_X1_A] = "quadrature x1 a",
+ [COUNTER_COUNT_FUNCTION_QUADRATURE_X1_B] = "quadrature x1 b",
+ [COUNTER_COUNT_FUNCTION_QUADRATURE_X2_A] = "quadrature x2 a",
+ [COUNTER_COUNT_FUNCTION_QUADRATURE_X2_B] = "quadrature x2 b",
+ [COUNTER_COUNT_FUNCTION_QUADRATURE_X4] = "quadrature x4"
+};
+
+static const char *const counter_signal_value_str[] = {
+ [COUNTER_SIGNAL_LOW] = "low",
+ [COUNTER_SIGNAL_HIGH] = "high"
+};
+
+static const char *const counter_synapse_action_str[] = {
+ [COUNTER_SYNAPSE_ACTION_NONE] = "none",
+ [COUNTER_SYNAPSE_ACTION_RISING_EDGE] = "rising edge",
+ [COUNTER_SYNAPSE_ACTION_FALLING_EDGE] = "falling edge",
+ [COUNTER_SYNAPSE_ACTION_BOTH_EDGES] = "both edges"
+};
+
+static const char *const counter_count_direction_str[] = {
+ [COUNTER_COUNT_DIRECTION_FORWARD] = "forward",
+ [COUNTER_COUNT_DIRECTION_BACKWARD] = "backward"
+};
+
+static const char *const counter_count_mode_str[] = {
+ [COUNTER_COUNT_MODE_NORMAL] = "normal",
+ [COUNTER_COUNT_MODE_RANGE_LIMIT] = "range limit",
+ [COUNTER_COUNT_MODE_NON_RECYCLE] = "non-recycle",
+ [COUNTER_COUNT_MODE_MODULO_N] = "modulo-n"
+};
+
+static ssize_t counter_data_u8_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ const struct counter_attribute *const a = to_counter_attribute(attr);
+ struct counter_device *const counter = dev_get_drvdata(dev);
+ const struct counter_available *const avail = a->data.priv;
+ int err;
+ u8 data;
+
+ switch (a->type) {
+ case COUNTER_OWNER_TYPE_DEVICE:
+ err = a->data.device_u8_read(counter, &data);
+ break;
+ case COUNTER_OWNER_TYPE_SIGNAL:
+ err = a->data.signal_u8_read(counter, a->owner, &data);
+ break;
+ case COUNTER_OWNER_TYPE_COUNT:
+ if (a->data.type == COUNTER_DATA_TYPE_SYNAPSE_ACTION)
+ err = a->data.action_read(counter, a->owner,
+ a->data.priv, &data);
+ else
+ err = a->data.count_u8_read(counter, a->owner, &data);
+ break;
+ }
+ if (err)
+ return err;
+
+ switch (a->data.type) {
+ case COUNTER_DATA_TYPE_BOOL:
+ return sprintf(buf, "%u\n", (unsigned int)!!data);
+ case COUNTER_DATA_TYPE_COUNT_FUNCTION:
+ return sprintf(buf, "%s\n", counter_count_function_str[data]);
+ case COUNTER_DATA_TYPE_SIGNAL:
+ return sprintf(buf, "%s\n", counter_signal_value_str[data]);
+ case COUNTER_DATA_TYPE_SYNAPSE_ACTION:
+ return sprintf(buf, "%s\n", counter_synapse_action_str[data]);
+ case COUNTER_DATA_TYPE_ENUM:
+ return sprintf(buf, "%s\n", avail->enums[data]);
+ case COUNTER_DATA_TYPE_COUNT_DIRECTION:
+ return sprintf(buf, "%s\n", counter_count_direction_str[data]);
+ case COUNTER_DATA_TYPE_COUNT_MODE:
+ return sprintf(buf, "%s\n", counter_count_mode_str[data]);
+ default:
+ break;
+ }
+
+ return sprintf(buf, "%u\n", (unsigned int)data);
+}
+
+static int find_in_string_array(u8 *const item, const u8 *const items,
+ const size_t num_items, const char *const buf,
+ const char *const string_array[])
+{
+ size_t index;
+
+ for (index = 0; index < num_items; index++) {
+ *item = items[index];
+ if (sysfs_streq(buf, string_array[*item]))
+ return 0;
+ }
+
+ return -EINVAL;
+}
+
+static ssize_t counter_data_u8_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t len)
+{
+ const struct counter_attribute *const a = to_counter_attribute(attr);
+ struct counter_device *const counter = dev_get_drvdata(dev);
+ struct counter_count *const count = a->owner;
+ struct counter_synapse *const synapse = a->data.priv;
+ const struct counter_available *const avail = a->data.priv;
+ int err;
+ bool bool_data;
+ u8 data;
+
+ switch (a->data.type) {
+ case COUNTER_DATA_TYPE_BOOL:
+ err = kstrtobool(buf, &bool_data);
+ data = bool_data;
+ break;
+ case COUNTER_DATA_TYPE_COUNT_FUNCTION:
+ err = find_in_string_array(&data, count->functions_list,
+ count->num_functions, buf,
+ counter_count_function_str);
+ break;
+ case COUNTER_DATA_TYPE_SYNAPSE_ACTION:
+ err = find_in_string_array(&data, synapse->actions_list,
+ synapse->num_actions, buf,
+ counter_synapse_action_str);
+ break;
+ case COUNTER_DATA_TYPE_ENUM:
+ err = __sysfs_match_string(avail->enums, avail->num_items, buf);
+ data = err;
+ break;
+ case COUNTER_DATA_TYPE_COUNT_MODE:
+ err = find_in_string_array(&data, avail->items,
+ avail->num_items, buf,
+ counter_count_mode_str);
+ break;
+ default:
+ err = kstrtou8(buf, 0, &data);
+ break;
+ }
+ if (err)
+ return err;
+
+ switch (a->type) {
+ case COUNTER_OWNER_TYPE_DEVICE:
+ err = a->data.device_u8_write(counter, data);
+ break;
+ case COUNTER_OWNER_TYPE_SIGNAL:
+ err = a->data.signal_u8_write(counter, a->owner, data);
+ break;
+ case COUNTER_OWNER_TYPE_COUNT:
+ if (a->data.type == COUNTER_DATA_TYPE_SYNAPSE_ACTION)
+ err = a->data.action_write(counter, count, synapse,
+ data);
+ else
+ err = a->data.count_u8_write(counter, count, data);
+ break;
+ }
+ if (err)
+ return err;
+
+ return len;
+}
+
+static ssize_t counter_data_u64_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ const struct counter_attribute *const a = to_counter_attribute(attr);
+ struct counter_device *const counter = dev_get_drvdata(dev);
+ int err;
+ u64 data;
+
+ switch (a->type) {
+ case COUNTER_OWNER_TYPE_DEVICE:
+ err = a->data.device_u64_read(counter, &data);
+ break;
+ case COUNTER_OWNER_TYPE_SIGNAL:
+ err = a->data.signal_u64_read(counter, a->owner, &data);
+ break;
+ case COUNTER_OWNER_TYPE_COUNT:
+ err = a->data.count_u64_read(counter, a->owner, &data);
+ break;
+ }
+ if (err)
+ return err;
+
+ return sprintf(buf, "%llu\n", (unsigned long long)data);
+}
+
+static ssize_t counter_data_u64_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t len)
+{
+ const struct counter_attribute *const a = to_counter_attribute(attr);
+ struct counter_device *const counter = dev_get_drvdata(dev);
+ int err;
+ u64 data;
+
+ err = kstrtou64(buf, 0, &data);
+ if (err)
+ return err;
+
+ switch (a->type) {
+ case COUNTER_OWNER_TYPE_DEVICE:
+ err = a->data.device_u64_write(counter, data);
+ break;
+ case COUNTER_OWNER_TYPE_SIGNAL:
+ err = a->data.signal_u64_write(counter, a->owner, data);
+ break;
+ case COUNTER_OWNER_TYPE_COUNT:
+ err = a->data.count_u64_write(counter, a->owner, data);
+ break;
+ }
+ if (err)
+ return err;
+
+ return len;
+}
+
+static ssize_t items_available_show(const u8 *const items,
+ const size_t num_items,
+ const char *const string_array[], char *buf)
+{
+ size_t len = 0;
+ size_t index;
+
+ for (index = 0; index < num_items; index++)
+ len += sprintf(buf + len, "%s\n", string_array[items[index]]);
+
+ return len;
+}
+
+static ssize_t enums_available_show(const struct counter_available *const avail,
+ char *buf)
+{
+ size_t len = 0;
+ size_t index;
+
+ for (index = 0; index < avail->num_items; index++)
+ len += sprintf(buf + len, "%s\n", avail->enums[index]);
+
+ return len;
+}
+
+static ssize_t counter_data_available_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ const struct counter_attribute *const a = to_counter_attribute(attr);
+ const struct counter_count *const count = a->owner;
+ const struct counter_synapse *const synapse = a->data.priv;
+ const struct counter_available *const avail = a->data.priv;
+
+ switch (a->data.type) {
+ case COUNTER_DATA_TYPE_COUNT_FUNCTION:
+ return items_available_show(count->functions_list,
+ count->num_functions,
+ counter_count_function_str, buf);
+ case COUNTER_DATA_TYPE_SYNAPSE_ACTION:
+ return items_available_show(synapse->actions_list,
+ synapse->num_actions,
+ counter_synapse_action_str, buf);
+ case COUNTER_DATA_TYPE_ENUM:
+ return enums_available_show(avail, buf);
+ case COUNTER_DATA_TYPE_COUNT_MODE:
+ return items_available_show(avail->items, avail->num_items,
+ counter_count_mode_str, buf);
+ default:
+ break;
+ }
+
+ return -EINVAL;
+}
+
+struct counter_dynamic_name {
+ struct list_head l;
+ const char *name;
+};
+
+static int counter_available_attribute_create(
+ struct counter_attribute_group *const group,
+ struct list_head *const names, const struct counter_data *const data,
+ void *const owner)
+{
+ struct counter_attribute *counter_attr;
+ struct device_attribute *dev_attr;
+ struct counter_dynamic_name *dyn_name;
+
+ /* Allocate Counter attribute */
+ counter_attr = kzalloc(sizeof(*counter_attr), GFP_KERNEL);
+ if (!counter_attr)
+ return -ENOMEM;
+ list_add(&counter_attr->l, &group->attr_list);
+ group->num_attr++;
+
+ /* Configure Counter attribute */
+ counter_attr->data = *data;
+ counter_attr->owner = owner;
+
+ /* Initialize sysfs attribute */
+ dev_attr = &counter_attr->dev_attr;
+ sysfs_attr_init(&dev_attr->attr);
+
+ /* Generate dynamic name list item */
+ dyn_name = kmalloc(sizeof(*dyn_name), GFP_KERNEL);
+ if (!dyn_name)
+ return -ENOMEM;
+ list_add(&dyn_name->l, names);
+
+ /* Generate available attribute name */
+ dyn_name->name = kasprintf(GFP_KERNEL, "%s_available", data->name);
+ if (!dyn_name->name)
+ return -ENOMEM;
+
+ /* Configure device attribute */
+ dev_attr->attr.name = dyn_name->name;
+ dev_attr->attr.mode = 0444;
+ dev_attr->show = counter_data_available_show;
+
+ return 0;
+}
+
+static int counter_attribute_create(struct counter_attribute_group *const group,
+ struct list_head *const names,
+ const struct counter_data *const data,
+ const enum counter_owner_type type,
+ void *const owner)
+{
+ struct counter_attribute *counter_attr;
+ struct device_attribute *dev_attr;
+
+ /* Allocate Counter attribute */
+ counter_attr = kzalloc(sizeof(*counter_attr), GFP_KERNEL);
+ if (!counter_attr)
+ return -ENOMEM;
+ list_add(&counter_attr->l, &group->attr_list);
+ group->num_attr++;
+
+ /* Configure Counter attribute */
+ counter_attr->data = *data;
+ counter_attr->type = type;
+ counter_attr->owner = owner;
+
+ /* Configure device attribute */
+ dev_attr = &counter_attr->dev_attr;
+ sysfs_attr_init(&dev_attr->attr);
+ dev_attr->attr.name = data->name;
+ switch (data->type) {
+ case COUNTER_DATA_TYPE_U8:
+ case COUNTER_DATA_TYPE_BOOL:
+ case COUNTER_DATA_TYPE_SIGNAL:
+ case COUNTER_DATA_TYPE_COUNT_FUNCTION:
+ case COUNTER_DATA_TYPE_SYNAPSE_ACTION:
+ case COUNTER_DATA_TYPE_ENUM:
+ case COUNTER_DATA_TYPE_COUNT_DIRECTION:
+ case COUNTER_DATA_TYPE_COUNT_MODE:
+ if (data->device_u8_read) {
+ dev_attr->attr.mode |= 0444;
+ dev_attr->show = counter_data_u8_show;
+ }
+ if (data->device_u8_write) {
+ dev_attr->attr.mode |= 0200;
+ dev_attr->store = counter_data_u8_store;
+ }
+ break;
+ case COUNTER_DATA_TYPE_U64:
+ if (data->device_u64_read) {
+ dev_attr->attr.mode |= 0444;
+ dev_attr->show = counter_data_u64_show;
+ }
+ if (data->device_u64_write) {
+ dev_attr->attr.mode |= 0200;
+ dev_attr->store = counter_data_u64_store;
+ }
+ break;
+ }
+
+ switch (data->type) {
+ case COUNTER_DATA_TYPE_COUNT_FUNCTION:
+ case COUNTER_DATA_TYPE_SYNAPSE_ACTION:
+ case COUNTER_DATA_TYPE_ENUM:
+ case COUNTER_DATA_TYPE_COUNT_MODE:
+ return counter_available_attribute_create(group, names, data,
+ owner);
+ default:
+ break;
+ }
+
+ return 0;
+}
+
+static ssize_t counter_data_name_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ return sprintf(buf, "%s\n", to_counter_attribute(attr)->data.name);
+}
+
+static int counter_name_attr_create(struct counter_attribute_group *const group,
+ const char *const name)
+{
+ struct counter_attribute *counter_attr;
+
+ /* Allocate Counter attribute */
+ counter_attr = kzalloc(sizeof(*counter_attr), GFP_KERNEL);
+ if (!counter_attr)
+ return -ENOMEM;
+ list_add(&counter_attr->l, &group->attr_list);
+ group->num_attr++;
+
+ /* Configure Counter attribute */
+ counter_attr->data.name = name;
+
+ /* Configure device attribute */
+ sysfs_attr_init(&counter_attr->dev_attr.attr);
+ counter_attr->dev_attr.attr.name = "name";
+ counter_attr->dev_attr.attr.mode = 0444;
+ counter_attr->dev_attr.show = counter_data_name_show;
+
+ return 0;
+}
+static struct counter_data counter_signal_data = {
+ .type = COUNTER_DATA_TYPE_SIGNAL,
+ .name = "signal",
+};
+
+static int counter_signal_attributes_create(
+ struct counter_attribute_group *const group,
+ struct counter_device *const counter,
+ struct counter_signal *const signal)
+{
+ struct list_head *const names = &counter->dynamic_names_list;
+ const enum counter_owner_type type = COUNTER_OWNER_TYPE_SIGNAL;
+ int err;
+ struct counter_data data;
+ size_t i;
+ const struct counter_data *ext;
+
+ /* Create main Signal attribute */
+ data = counter_signal_data;
+ data.signal_u8_read = counter->signal_read;
+ err = counter_attribute_create(group, names, &data, type, signal);
+ if (err)
+ return err;
+
+ /* Create Signal name attribute */
+ err = counter_name_attr_create(group, signal->name);
+ if (err)
+ return err;
+
+ /* Create an attribute for each extension */
+ for (i = 0; i < signal->num_ext; i++) {
+ ext = signal->ext + i;
+ err = counter_attribute_create(group, names, ext, type, signal);
+ if (err)
+ return err;
+ }
+
+ return 0;
+}
+
+static int counter_signals_register(
+ struct counter_attribute_group *const groups_list,
+ struct counter_device *const counter)
+{
+ size_t i;
+ const char *name;
+ int err;
+
+ /* Register each Signal */
+ for (i = 0; i < counter->num_signals; i++) {
+ /* Generate Signal attribute directory name */
+ name = kasprintf(GFP_KERNEL, "signal%zu", i);
+ if (!name)
+ return -ENOMEM;
+ groups_list[i].attr_group.name = name;
+
+ /* Create all attributes associated with Signal */
+ err = counter_signal_attributes_create(groups_list + i, counter,
+ counter->signals + i);
+ if (err)
+ return err;
+ }
+
+ return 0;
+}
+
+static int counter_synapses_register(
+ struct counter_attribute_group *const group,
+ struct counter_device *const counter, struct counter_count *const count)
+{
+ struct list_head *const names = &counter->dynamic_names_list;
+ const enum counter_owner_type type = COUNTER_OWNER_TYPE_COUNT;
+ size_t i;
+ struct counter_synapse *synapse;
+ struct counter_dynamic_name *dyn_name;
+ size_t id;
+ struct counter_data data;
+ int err;
+
+ /* Register each Synapse */
+ for (i = 0; i < count->num_synapses; i++) {
+ synapse = count->synapses + i;
+
+ /* Generate dynamic name list item */
+ dyn_name = kmalloc(sizeof(*dyn_name), GFP_KERNEL);
+ if (!dyn_name)
+ return -ENOMEM;
+ list_add(&dyn_name->l, names);
+
+ /* Generate Synapse action name */
+ id = synapse->signal - counter->signals;
+ dyn_name->name = kasprintf(GFP_KERNEL, "signal%zu_action", id);
+ if (!dyn_name->name)
+ return -ENOMEM;
+
+ /* Create action attribute */
+ data.type = COUNTER_DATA_TYPE_SYNAPSE_ACTION;
+ data.name = dyn_name->name;
+ data.action_read = counter->action_read;
+ data.action_write = counter->action_write;
+ data.priv = synapse;
+ err = counter_attribute_create(group, names, &data, type,
+ count);
+ if (err)
+ return err;
+ }
+
+ return 0;
+}
+
+static struct counter_data counter_count_data =
+ COUNTER_DATA_COUNT_U64("count", NULL, NULL);
+
+static struct counter_data counter_count_function_data = {
+ .type = COUNTER_DATA_TYPE_COUNT_FUNCTION,
+ .name = "function",
+};
+
+static int counter_count_attributes_create(
+ struct counter_attribute_group *const group,
+ struct counter_device *const counter,
+ struct counter_count *const count)
+{
+ struct list_head *const names = &counter->dynamic_names_list;
+ const enum counter_owner_type type = COUNTER_OWNER_TYPE_COUNT;
+ int err;
+ struct counter_data data;
+ size_t i;
+ const struct counter_data *ext;
+
+ /* Create main Count attribute */
+ data = counter_count_data;
+ data.count_u64_read = counter->count_read;
+ data.count_u64_write = counter->count_write;
+ err = counter_attribute_create(group, names, &data, type, count);
+ if (err)
+ return err;
+
+ /* Create Count name attribute */
+ err = counter_name_attr_create(group, count->name);
+ if (err)
+ return err;
+
+ /* Create Count function attribute */
+ data = counter_count_function_data;
+ data.count_u8_read = counter->function_read;
+ data.count_u8_write = counter->function_write;
+ err = counter_attribute_create(group, names, &data, type, count);
+ if (err)
+ return err;
+
+ /* Create an attribute for each extension */
+ for (i = 0; i < count->num_ext; i++) {
+ ext = count->ext + i;
+ err = counter_attribute_create(group, names, ext, type, count);
+ if (err)
+ return err;
+ }
+
+ return 0;
+}
+
+static int counter_counts_register(
+ struct counter_attribute_group *const groups_list,
+ struct counter_device *const counter)
+{
+ size_t i;
+ struct counter_count *count;
+ const char *name;
+ int err;
+
+ /* Register each Count */
+ for (i = 0; i < counter->num_counts; i++) {
+ count = counter->counts + i;
+
+ /* Generate Count attribute directory name */
+ name = kasprintf(GFP_KERNEL, "count%zu", i);
+ if (!name)
+ return -ENOMEM;
+ groups_list[i].attr_group.name = name;
+
+ /* Register the Synapses associated with each Count */
+ err = counter_synapses_register(groups_list + i, counter,
+ count);
+ if (err)
+ return err;
+
+ /* Create all attributes associated with Count */
+ err = counter_count_attributes_create(groups_list + i, counter,
+ count);
+ if (err)
+ return err;
+ }
+
+ return 0;
+}
+
+static int counter_num_signals_read(struct counter_device *counter, u8 *val)
+{
+ *val = counter->num_signals;
+ return 0;
+}
+
+static int counter_num_counts_read(struct counter_device *counter, u8 *val)
+{
+ *val = counter->num_counts;
+ return 0;
+}
+
+static struct counter_data counter_num_signals_data =
+ COUNTER_DATA_DEVICE_U8("num_signals", counter_num_signals_read, NULL);
+
+static struct counter_data counter_num_counts_data =
+ COUNTER_DATA_DEVICE_U8("num_counts", counter_num_counts_read, NULL);
+
+static void counter_groups_list_free(struct counter_device *const counter)
+{
+ struct counter_attribute_group *group;
+ struct counter_attribute *p, *n;
+
+ /* Loop through all attribute groups (signals, counts, device, etc.) */
+ while (counter->num_groups--) {
+ group = counter->groups_list + counter->num_groups;
+
+ /* Free all attribute group and associated attributes memory */
+ kfree(group->attr_group.name);
+ kfree(group->attr_group.attrs);
+
+ /* Free attribute list */
+ list_for_each_entry_safe(p, n, &group->attr_list, l)
+ kfree(p);
+ }
+
+ kfree(counter->groups_list);
+}
+
+static int counter_device_register(struct counter_attribute_group *group,
+ struct counter_device *const counter)
+{
+ struct list_head *const names = &counter->dynamic_names_list;
+ const enum counter_owner_type type = COUNTER_OWNER_TYPE_DEVICE;
+ struct counter_data data;
+ int err;
+ size_t i;
+ const struct counter_data *ext;
+
+ /* Register Signals */
+ err = counter_signals_register(group, counter);
+ if (err)
+ goto err_free_groups_list;
+ group += counter->num_signals;
+
+ /* Register Counts and respective Synapses */
+ err = counter_counts_register(group, counter);
+ if (err)
+ goto err_free_groups_list;
+ group += counter->num_counts;
+
+ /* Create name attribute */
+ err = counter_name_attr_create(group, counter->name);
+ if (err)
+ goto err_free_groups_list;
+
+ /* Create num_signals attribute */
+ data = counter_num_signals_data;
+ err = counter_attribute_create(group, names, &data, type, NULL);
+ if (err)
+ goto err_free_groups_list;
+
+ /* Create num_counts attribute */
+ data = counter_num_counts_data;
+ err = counter_attribute_create(group, names, &data, type, NULL);
+ if (err)
+ goto err_free_groups_list;
+
+ /* Create an attribute for each extension */
+ for (i = 0; i < counter->num_ext; i++) {
+ ext = counter->ext + i;
+ err = counter_attribute_create(group, names, ext, type, NULL);
+ if (err)
+ goto err_free_groups_list;
+ }
+
+ return 0;
+
+err_free_groups_list:
+ counter_groups_list_free(counter);
+ return err;
+}
+
+static int counter_groups_list_prepare(struct counter_device *const counter)
+{
+ const size_t num_grps = counter->num_signals + counter->num_counts + 1;
+ struct counter_attribute_group *groups_list;
+ size_t i;
+
+ /* Allocate space for attribute groups (signals, counts, and ext) */
+ groups_list = kcalloc(num_grps, sizeof(*groups_list), GFP_KERNEL);
+ if (!groups_list)
+ return -ENOMEM;
+
+ /* Store groups_list in counter structure */
+ counter->groups_list = groups_list;
+ counter->num_groups = num_grps;
+
+ /* Initialize attribute lists */
+ for (i = 0; i < num_grps; i++)
+ INIT_LIST_HEAD(&groups_list[i].attr_list);
+
+ /* Register Counter device attributes */
+ return counter_device_register(groups_list, counter);
+}
+
+static int counter_groups_prepare(struct counter_device *const counter)
+{
+ size_t i, j;
+ struct counter_attribute_group *group;
+ struct attribute **attrs;
+ int err;
+ struct counter_attribute *p;
+
+ /* Allocate attribute groups for association with device */
+ counter->groups = kcalloc(counter->num_groups + 1,
+ sizeof(*counter->groups), GFP_KERNEL);
+ if (!counter->groups)
+ return -ENOMEM;
+
+ /* Prepare each group of attributes for association */
+ for (i = 0; i < counter->num_groups; i++) {
+ group = counter->groups_list + i;
+
+ /* Allocate space for attribute pointers */
+ attrs = kcalloc(group->num_attr + 1, sizeof(*attrs),
+ GFP_KERNEL);
+ if (!attrs) {
+ err = -ENOMEM;
+ goto err_free_groups;
+ }
+ group->attr_group.attrs = attrs;
+
+ /* Add attribute pointers to attribute group */
+ j = 0;
+ list_for_each_entry(p, &group->attr_list, l)
+ attrs[j++] = &p->dev_attr.attr;
+
+ /* Group attributes in attribute group */
+ counter->groups[i] = &group->attr_group;
+ }
+ /* Associate attributes with device */
+ counter->dev.groups = counter->groups;
+
+ return 0;
+
+err_free_groups:
+ kfree(counter->groups);
+ return err;
+}
+
+static void counter_dynamic_names_free(struct list_head *const names)
+{
+ struct counter_dynamic_name *p, *n;
+
+ list_for_each_entry_safe(p, n, names, l) {
+ kfree(p->name);
+ kfree(p);
+ }
+}
+
+int counter_sysfs_add(struct counter_device *const counter)
+{
+ int err;
+
+ /* Initialize Synapse names list */
+ INIT_LIST_HEAD(&counter->dynamic_names_list);
+
+ /* Prepare device attributes */
+ err = counter_groups_list_prepare(counter);
+ if (err)
+ goto err_free_names;
+
+ /* Organize device attributes to groups and match to device */
+ err = counter_groups_prepare(counter);
+ if (err)
+ goto err_free_groups_list;
+
+ return 0;
+
+err_free_groups_list:
+ counter_groups_list_free(counter);
+err_free_names:
+ counter_dynamic_names_free(&counter->dynamic_names_list);
+ return err;
+}
+
+void counter_sysfs_free(struct counter_device *const counter)
+{
+ kfree(counter->groups);
+ counter_groups_list_free(counter);
+ counter_dynamic_names_free(&counter->dynamic_names_list);
+}
diff --git a/drivers/counter/counter-sysfs.h b/drivers/counter/counter-sysfs.h
new file mode 100644
index 000000000000..00e7cd6ea083
--- /dev/null
+++ b/drivers/counter/counter-sysfs.h
@@ -0,0 +1,14 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Counter sysfs interface
+ * Copyright (C) 2020 William Breathitt Gray
+ */
+#ifndef _COUNTER_SYSFS_H_
+#define _COUNTER_SYSFS_H_
+
+#include <linux/counter.h>
+
+int counter_sysfs_add(struct counter_device *const counter);
+void counter_sysfs_free(struct counter_device *const counter);
+
+#endif /* _COUNTER_SYSFS_H_ */
diff --git a/drivers/counter/counter.c b/drivers/counter/counter.c
deleted file mode 100644
index 6a683d086008..000000000000
--- a/drivers/counter/counter.c
+++ /dev/null
@@ -1,1496 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0
-/*
- * Generic Counter interface
- * Copyright (C) 2018 William Breathitt Gray
- */
-#include <linux/counter.h>
-#include <linux/device.h>
-#include <linux/err.h>
-#include <linux/export.h>
-#include <linux/fs.h>
-#include <linux/gfp.h>
-#include <linux/idr.h>
-#include <linux/init.h>
-#include <linux/kernel.h>
-#include <linux/list.h>
-#include <linux/module.h>
-#include <linux/printk.h>
-#include <linux/slab.h>
-#include <linux/string.h>
-#include <linux/sysfs.h>
-#include <linux/types.h>
-
-const char *const counter_count_direction_str[2] = {
- [COUNTER_COUNT_DIRECTION_FORWARD] = "forward",
- [COUNTER_COUNT_DIRECTION_BACKWARD] = "backward"
-};
-EXPORT_SYMBOL_GPL(counter_count_direction_str);
-
-const char *const counter_count_mode_str[4] = {
- [COUNTER_COUNT_MODE_NORMAL] = "normal",
- [COUNTER_COUNT_MODE_RANGE_LIMIT] = "range limit",
- [COUNTER_COUNT_MODE_NON_RECYCLE] = "non-recycle",
- [COUNTER_COUNT_MODE_MODULO_N] = "modulo-n"
-};
-EXPORT_SYMBOL_GPL(counter_count_mode_str);
-
-ssize_t counter_signal_enum_read(struct counter_device *counter,
- struct counter_signal *signal, void *priv,
- char *buf)
-{
- const struct counter_signal_enum_ext *const e = priv;
- int err;
- size_t index;
-
- if (!e->get)
- return -EINVAL;
-
- err = e->get(counter, signal, &index);
- if (err)
- return err;
-
- if (index >= e->num_items)
- return -EINVAL;
-
- return sprintf(buf, "%s\n", e->items[index]);
-}
-EXPORT_SYMBOL_GPL(counter_signal_enum_read);
-
-ssize_t counter_signal_enum_write(struct counter_device *counter,
- struct counter_signal *signal, void *priv,
- const char *buf, size_t len)
-{
- const struct counter_signal_enum_ext *const e = priv;
- ssize_t index;
- int err;
-
- if (!e->set)
- return -EINVAL;
-
- index = __sysfs_match_string(e->items, e->num_items, buf);
- if (index < 0)
- return index;
-
- err = e->set(counter, signal, index);
- if (err)
- return err;
-
- return len;
-}
-EXPORT_SYMBOL_GPL(counter_signal_enum_write);
-
-ssize_t counter_signal_enum_available_read(struct counter_device *counter,
- struct counter_signal *signal,
- void *priv, char *buf)
-{
- const struct counter_signal_enum_ext *const e = priv;
- size_t i;
- size_t len = 0;
-
- if (!e->num_items)
- return 0;
-
- for (i = 0; i < e->num_items; i++)
- len += sprintf(buf + len, "%s\n", e->items[i]);
-
- return len;
-}
-EXPORT_SYMBOL_GPL(counter_signal_enum_available_read);
-
-ssize_t counter_count_enum_read(struct counter_device *counter,
- struct counter_count *count, void *priv,
- char *buf)
-{
- const struct counter_count_enum_ext *const e = priv;
- int err;
- size_t index;
-
- if (!e->get)
- return -EINVAL;
-
- err = e->get(counter, count, &index);
- if (err)
- return err;
-
- if (index >= e->num_items)
- return -EINVAL;
-
- return sprintf(buf, "%s\n", e->items[index]);
-}
-EXPORT_SYMBOL_GPL(counter_count_enum_read);
-
-ssize_t counter_count_enum_write(struct counter_device *counter,
- struct counter_count *count, void *priv,
- const char *buf, size_t len)
-{
- const struct counter_count_enum_ext *const e = priv;
- ssize_t index;
- int err;
-
- if (!e->set)
- return -EINVAL;
-
- index = __sysfs_match_string(e->items, e->num_items, buf);
- if (index < 0)
- return index;
-
- err = e->set(counter, count, index);
- if (err)
- return err;
-
- return len;
-}
-EXPORT_SYMBOL_GPL(counter_count_enum_write);
-
-ssize_t counter_count_enum_available_read(struct counter_device *counter,
- struct counter_count *count,
- void *priv, char *buf)
-{
- const struct counter_count_enum_ext *const e = priv;
- size_t i;
- size_t len = 0;
-
- if (!e->num_items)
- return 0;
-
- for (i = 0; i < e->num_items; i++)
- len += sprintf(buf + len, "%s\n", e->items[i]);
-
- return len;
-}
-EXPORT_SYMBOL_GPL(counter_count_enum_available_read);
-
-ssize_t counter_device_enum_read(struct counter_device *counter, void *priv,
- char *buf)
-{
- const struct counter_device_enum_ext *const e = priv;
- int err;
- size_t index;
-
- if (!e->get)
- return -EINVAL;
-
- err = e->get(counter, &index);
- if (err)
- return err;
-
- if (index >= e->num_items)
- return -EINVAL;
-
- return sprintf(buf, "%s\n", e->items[index]);
-}
-EXPORT_SYMBOL_GPL(counter_device_enum_read);
-
-ssize_t counter_device_enum_write(struct counter_device *counter, void *priv,
- const char *buf, size_t len)
-{
- const struct counter_device_enum_ext *const e = priv;
- ssize_t index;
- int err;
-
- if (!e->set)
- return -EINVAL;
-
- index = __sysfs_match_string(e->items, e->num_items, buf);
- if (index < 0)
- return index;
-
- err = e->set(counter, index);
- if (err)
- return err;
-
- return len;
-}
-EXPORT_SYMBOL_GPL(counter_device_enum_write);
-
-ssize_t counter_device_enum_available_read(struct counter_device *counter,
- void *priv, char *buf)
-{
- const struct counter_device_enum_ext *const e = priv;
- size_t i;
- size_t len = 0;
-
- if (!e->num_items)
- return 0;
-
- for (i = 0; i < e->num_items; i++)
- len += sprintf(buf + len, "%s\n", e->items[i]);
-
- return len;
-}
-EXPORT_SYMBOL_GPL(counter_device_enum_available_read);
-
-struct counter_attr_parm {
- struct counter_device_attr_group *group;
- const char *prefix;
- const char *name;
- ssize_t (*show)(struct device *dev, struct device_attribute *attr,
- char *buf);
- ssize_t (*store)(struct device *dev, struct device_attribute *attr,
- const char *buf, size_t len);
- void *component;
-};
-
-struct counter_device_attr {
- struct device_attribute dev_attr;
- struct list_head l;
- void *component;
-};
-
-static int counter_attribute_create(const struct counter_attr_parm *const parm)
-{
- struct counter_device_attr *counter_attr;
- struct device_attribute *dev_attr;
- int err;
- struct list_head *const attr_list = &parm->group->attr_list;
-
- /* Allocate a Counter device attribute */
- counter_attr = kzalloc(sizeof(*counter_attr), GFP_KERNEL);
- if (!counter_attr)
- return -ENOMEM;
- dev_attr = &counter_attr->dev_attr;
-
- sysfs_attr_init(&dev_attr->attr);
-
- /* Configure device attribute */
- dev_attr->attr.name = kasprintf(GFP_KERNEL, "%s%s", parm->prefix,
- parm->name);
- if (!dev_attr->attr.name) {
- err = -ENOMEM;
- goto err_free_counter_attr;
- }
- if (parm->show) {
- dev_attr->attr.mode |= 0444;
- dev_attr->show = parm->show;
- }
- if (parm->store) {
- dev_attr->attr.mode |= 0200;
- dev_attr->store = parm->store;
- }
-
- /* Store associated Counter component with attribute */
- counter_attr->component = parm->component;
-
- /* Keep track of the attribute for later cleanup */
- list_add(&counter_attr->l, attr_list);
- parm->group->num_attr++;
-
- return 0;
-
-err_free_counter_attr:
- kfree(counter_attr);
- return err;
-}
-
-#define to_counter_attr(_dev_attr) \
- container_of(_dev_attr, struct counter_device_attr, dev_attr)
-
-struct counter_signal_unit {
- struct counter_signal *signal;
-};
-
-static const char *const counter_signal_value_str[] = {
- [COUNTER_SIGNAL_LOW] = "low",
- [COUNTER_SIGNAL_HIGH] = "high"
-};
-
-static ssize_t counter_signal_show(struct device *dev,
- struct device_attribute *attr, char *buf)
-{
- struct counter_device *const counter = dev_get_drvdata(dev);
- const struct counter_device_attr *const devattr = to_counter_attr(attr);
- const struct counter_signal_unit *const component = devattr->component;
- struct counter_signal *const signal = component->signal;
- int err;
- enum counter_signal_value val;
-
- err = counter->ops->signal_read(counter, signal, &val);
- if (err)
- return err;
-
- return sprintf(buf, "%s\n", counter_signal_value_str[val]);
-}
-
-struct counter_name_unit {
- const char *name;
-};
-
-static ssize_t counter_device_attr_name_show(struct device *dev,
- struct device_attribute *attr,
- char *buf)
-{
- const struct counter_name_unit *const comp = to_counter_attr(attr)->component;
-
- return sprintf(buf, "%s\n", comp->name);
-}
-
-static int counter_name_attribute_create(
- struct counter_device_attr_group *const group,
- const char *const name)
-{
- struct counter_name_unit *name_comp;
- struct counter_attr_parm parm;
- int err;
-
- /* Skip if no name */
- if (!name)
- return 0;
-
- /* Allocate name attribute component */
- name_comp = kmalloc(sizeof(*name_comp), GFP_KERNEL);
- if (!name_comp)
- return -ENOMEM;
- name_comp->name = name;
-
- /* Allocate Signal name attribute */
- parm.group = group;
- parm.prefix = "";
- parm.name = "name";
- parm.show = counter_device_attr_name_show;
- parm.store = NULL;
- parm.component = name_comp;
- err = counter_attribute_create(&parm);
- if (err)
- goto err_free_name_comp;
-
- return 0;
-
-err_free_name_comp:
- kfree(name_comp);
- return err;
-}
-
-struct counter_signal_ext_unit {
- struct counter_signal *signal;
- const struct counter_signal_ext *ext;
-};
-
-static ssize_t counter_signal_ext_show(struct device *dev,
- struct device_attribute *attr, char *buf)
-{
- const struct counter_device_attr *const devattr = to_counter_attr(attr);
- const struct counter_signal_ext_unit *const comp = devattr->component;
- const struct counter_signal_ext *const ext = comp->ext;
-
- return ext->read(dev_get_drvdata(dev), comp->signal, ext->priv, buf);
-}
-
-static ssize_t counter_signal_ext_store(struct device *dev,
- struct device_attribute *attr,
- const char *buf, size_t len)
-{
- const struct counter_device_attr *const devattr = to_counter_attr(attr);
- const struct counter_signal_ext_unit *const comp = devattr->component;
- const struct counter_signal_ext *const ext = comp->ext;
-
- return ext->write(dev_get_drvdata(dev), comp->signal, ext->priv, buf,
- len);
-}
-
-static void counter_device_attr_list_free(struct list_head *attr_list)
-{
- struct counter_device_attr *p, *n;
-
- list_for_each_entry_safe(p, n, attr_list, l) {
- /* free attribute name and associated component memory */
- kfree(p->dev_attr.attr.name);
- kfree(p->component);
- list_del(&p->l);
- kfree(p);
- }
-}
-
-static int counter_signal_ext_register(
- struct counter_device_attr_group *const group,
- struct counter_signal *const signal)
-{
- const size_t num_ext = signal->num_ext;
- size_t i;
- const struct counter_signal_ext *ext;
- struct counter_signal_ext_unit *signal_ext_comp;
- struct counter_attr_parm parm;
- int err;
-
- /* Create an attribute for each extension */
- for (i = 0 ; i < num_ext; i++) {
- ext = signal->ext + i;
-
- /* Allocate signal_ext attribute component */
- signal_ext_comp = kmalloc(sizeof(*signal_ext_comp), GFP_KERNEL);
- if (!signal_ext_comp) {
- err = -ENOMEM;
- goto err_free_attr_list;
- }
- signal_ext_comp->signal = signal;
- signal_ext_comp->ext = ext;
-
- /* Allocate a Counter device attribute */
- parm.group = group;
- parm.prefix = "";
- parm.name = ext->name;
- parm.show = (ext->read) ? counter_signal_ext_show : NULL;
- parm.store = (ext->write) ? counter_signal_ext_store : NULL;
- parm.component = signal_ext_comp;
- err = counter_attribute_create(&parm);
- if (err) {
- kfree(signal_ext_comp);
- goto err_free_attr_list;
- }
- }
-
- return 0;
-
-err_free_attr_list:
- counter_device_attr_list_free(&group->attr_list);
- return err;
-}
-
-static int counter_signal_attributes_create(
- struct counter_device_attr_group *const group,
- const struct counter_device *const counter,
- struct counter_signal *const signal)
-{
- struct counter_signal_unit *signal_comp;
- struct counter_attr_parm parm;
- int err;
-
- /* Allocate Signal attribute component */
- signal_comp = kmalloc(sizeof(*signal_comp), GFP_KERNEL);
- if (!signal_comp)
- return -ENOMEM;
- signal_comp->signal = signal;
-
- /* Create main Signal attribute */
- parm.group = group;
- parm.prefix = "";
- parm.name = "signal";
- parm.show = (counter->ops->signal_read) ? counter_signal_show : NULL;
- parm.store = NULL;
- parm.component = signal_comp;
- err = counter_attribute_create(&parm);
- if (err) {
- kfree(signal_comp);
- return err;
- }
-
- /* Create Signal name attribute */
- err = counter_name_attribute_create(group, signal->name);
- if (err)
- goto err_free_attr_list;
-
- /* Register Signal extension attributes */
- err = counter_signal_ext_register(group, signal);
- if (err)
- goto err_free_attr_list;
-
- return 0;
-
-err_free_attr_list:
- counter_device_attr_list_free(&group->attr_list);
- return err;
-}
-
-static int counter_signals_register(
- struct counter_device_attr_group *const groups_list,
- const struct counter_device *const counter)
-{
- const size_t num_signals = counter->num_signals;
- size_t i;
- struct counter_signal *signal;
- const char *name;
- int err;
-
- /* Register each Signal */
- for (i = 0; i < num_signals; i++) {
- signal = counter->signals + i;
-
- /* Generate Signal attribute directory name */
- name = kasprintf(GFP_KERNEL, "signal%d", signal->id);
- if (!name) {
- err = -ENOMEM;
- goto err_free_attr_groups;
- }
- groups_list[i].attr_group.name = name;
-
- /* Create all attributes associated with Signal */
- err = counter_signal_attributes_create(groups_list + i, counter,
- signal);
- if (err)
- goto err_free_attr_groups;
- }
-
- return 0;
-
-err_free_attr_groups:
- do {
- kfree(groups_list[i].attr_group.name);
- counter_device_attr_list_free(&groups_list[i].attr_list);
- } while (i--);
- return err;
-}
-
-static const char *const counter_synapse_action_str[] = {
- [COUNTER_SYNAPSE_ACTION_NONE] = "none",
- [COUNTER_SYNAPSE_ACTION_RISING_EDGE] = "rising edge",
- [COUNTER_SYNAPSE_ACTION_FALLING_EDGE] = "falling edge",
- [COUNTER_SYNAPSE_ACTION_BOTH_EDGES] = "both edges"
-};
-
-struct counter_action_unit {
- struct counter_synapse *synapse;
- struct counter_count *count;
-};
-
-static ssize_t counter_action_show(struct device *dev,
- struct device_attribute *attr, char *buf)
-{
- const struct counter_device_attr *const devattr = to_counter_attr(attr);
- int err;
- struct counter_device *const counter = dev_get_drvdata(dev);
- const struct counter_action_unit *const component = devattr->component;
- struct counter_count *const count = component->count;
- struct counter_synapse *const synapse = component->synapse;
- size_t action_index;
- enum counter_synapse_action action;
-
- err = counter->ops->action_get(counter, count, synapse, &action_index);
- if (err)
- return err;
-
- synapse->action = action_index;
-
- action = synapse->actions_list[action_index];
- return sprintf(buf, "%s\n", counter_synapse_action_str[action]);
-}
-
-static ssize_t counter_action_store(struct device *dev,
- struct device_attribute *attr,
- const char *buf, size_t len)
-{
- const struct counter_device_attr *const devattr = to_counter_attr(attr);
- const struct counter_action_unit *const component = devattr->component;
- struct counter_synapse *const synapse = component->synapse;
- size_t action_index;
- const size_t num_actions = synapse->num_actions;
- enum counter_synapse_action action;
- int err;
- struct counter_device *const counter = dev_get_drvdata(dev);
- struct counter_count *const count = component->count;
-
- /* Find requested action mode */
- for (action_index = 0; action_index < num_actions; action_index++) {
- action = synapse->actions_list[action_index];
- if (sysfs_streq(buf, counter_synapse_action_str[action]))
- break;
- }
- /* If requested action mode not found */
- if (action_index >= num_actions)
- return -EINVAL;
-
- err = counter->ops->action_set(counter, count, synapse, action_index);
- if (err)
- return err;
-
- synapse->action = action_index;
-
- return len;
-}
-
-struct counter_action_avail_unit {
- const enum counter_synapse_action *actions_list;
- size_t num_actions;
-};
-
-static ssize_t counter_synapse_action_available_show(struct device *dev,
- struct device_attribute *attr, char *buf)
-{
- const struct counter_device_attr *const devattr = to_counter_attr(attr);
- const struct counter_action_avail_unit *const component = devattr->component;
- size_t i;
- enum counter_synapse_action action;
- ssize_t len = 0;
-
- for (i = 0; i < component->num_actions; i++) {
- action = component->actions_list[i];
- len += sprintf(buf + len, "%s\n",
- counter_synapse_action_str[action]);
- }
-
- return len;
-}
-
-static int counter_synapses_register(
- struct counter_device_attr_group *const group,
- const struct counter_device *const counter,
- struct counter_count *const count, const char *const count_attr_name)
-{
- size_t i;
- struct counter_synapse *synapse;
- const char *prefix;
- struct counter_action_unit *action_comp;
- struct counter_attr_parm parm;
- int err;
- struct counter_action_avail_unit *avail_comp;
-
- /* Register each Synapse */
- for (i = 0; i < count->num_synapses; i++) {
- synapse = count->synapses + i;
-
- /* Generate attribute prefix */
- prefix = kasprintf(GFP_KERNEL, "signal%d_",
- synapse->signal->id);
- if (!prefix) {
- err = -ENOMEM;
- goto err_free_attr_list;
- }
-
- /* Allocate action attribute component */
- action_comp = kmalloc(sizeof(*action_comp), GFP_KERNEL);
- if (!action_comp) {
- err = -ENOMEM;
- goto err_free_prefix;
- }
- action_comp->synapse = synapse;
- action_comp->count = count;
-
- /* Create action attribute */
- parm.group = group;
- parm.prefix = prefix;
- parm.name = "action";
- parm.show = (counter->ops->action_get) ? counter_action_show : NULL;
- parm.store = (counter->ops->action_set) ? counter_action_store : NULL;
- parm.component = action_comp;
- err = counter_attribute_create(&parm);
- if (err) {
- kfree(action_comp);
- goto err_free_prefix;
- }
-
- /* Allocate action available attribute component */
- avail_comp = kmalloc(sizeof(*avail_comp), GFP_KERNEL);
- if (!avail_comp) {
- err = -ENOMEM;
- goto err_free_prefix;
- }
- avail_comp->actions_list = synapse->actions_list;
- avail_comp->num_actions = synapse->num_actions;
-
- /* Create action_available attribute */
- parm.group = group;
- parm.prefix = prefix;
- parm.name = "action_available";
- parm.show = counter_synapse_action_available_show;
- parm.store = NULL;
- parm.component = avail_comp;
- err = counter_attribute_create(&parm);
- if (err) {
- kfree(avail_comp);
- goto err_free_prefix;
- }
-
- kfree(prefix);
- }
-
- return 0;
-
-err_free_prefix:
- kfree(prefix);
-err_free_attr_list:
- counter_device_attr_list_free(&group->attr_list);
- return err;
-}
-
-struct counter_count_unit {
- struct counter_count *count;
-};
-
-static ssize_t counter_count_show(struct device *dev,
- struct device_attribute *attr,
- char *buf)
-{
- struct counter_device *const counter = dev_get_drvdata(dev);
- const struct counter_device_attr *const devattr = to_counter_attr(attr);
- const struct counter_count_unit *const component = devattr->component;
- struct counter_count *const count = component->count;
- int err;
- unsigned long val;
-
- err = counter->ops->count_read(counter, count, &val);
- if (err)
- return err;
-
- return sprintf(buf, "%lu\n", val);
-}
-
-static ssize_t counter_count_store(struct device *dev,
- struct device_attribute *attr,
- const char *buf, size_t len)
-{
- struct counter_device *const counter = dev_get_drvdata(dev);
- const struct counter_device_attr *const devattr = to_counter_attr(attr);
- const struct counter_count_unit *const component = devattr->component;
- struct counter_count *const count = component->count;
- int err;
- unsigned long val;
-
- err = kstrtoul(buf, 0, &val);
- if (err)
- return err;
-
- err = counter->ops->count_write(counter, count, val);
- if (err)
- return err;
-
- return len;
-}
-
-static const char *const counter_count_function_str[] = {
- [COUNTER_COUNT_FUNCTION_INCREASE] = "increase",
- [COUNTER_COUNT_FUNCTION_DECREASE] = "decrease",
- [COUNTER_COUNT_FUNCTION_PULSE_DIRECTION] = "pulse-direction",
- [COUNTER_COUNT_FUNCTION_QUADRATURE_X1_A] = "quadrature x1 a",
- [COUNTER_COUNT_FUNCTION_QUADRATURE_X1_B] = "quadrature x1 b",
- [COUNTER_COUNT_FUNCTION_QUADRATURE_X2_A] = "quadrature x2 a",
- [COUNTER_COUNT_FUNCTION_QUADRATURE_X2_B] = "quadrature x2 b",
- [COUNTER_COUNT_FUNCTION_QUADRATURE_X4] = "quadrature x4"
-};
-
-static ssize_t counter_function_show(struct device *dev,
- struct device_attribute *attr, char *buf)
-{
- int err;
- struct counter_device *const counter = dev_get_drvdata(dev);
- const struct counter_device_attr *const devattr = to_counter_attr(attr);
- const struct counter_count_unit *const component = devattr->component;
- struct counter_count *const count = component->count;
- size_t func_index;
- enum counter_count_function function;
-
- err = counter->ops->function_get(counter, count, &func_index);
- if (err)
- return err;
-
- count->function = func_index;
-
- function = count->functions_list[func_index];
- return sprintf(buf, "%s\n", counter_count_function_str[function]);
-}
-
-static ssize_t counter_function_store(struct device *dev,
- struct device_attribute *attr,
- const char *buf, size_t len)
-{
- const struct counter_device_attr *const devattr = to_counter_attr(attr);
- const struct counter_count_unit *const component = devattr->component;
- struct counter_count *const count = component->count;
- const size_t num_functions = count->num_functions;
- size_t func_index;
- enum counter_count_function function;
- int err;
- struct counter_device *const counter = dev_get_drvdata(dev);
-
- /* Find requested Count function mode */
- for (func_index = 0; func_index < num_functions; func_index++) {
- function = count->functions_list[func_index];
- if (sysfs_streq(buf, counter_count_function_str[function]))
- break;
- }
- /* Return error if requested Count function mode not found */
- if (func_index >= num_functions)
- return -EINVAL;
-
- err = counter->ops->function_set(counter, count, func_index);
- if (err)
- return err;
-
- count->function = func_index;
-
- return len;
-}
-
-struct counter_count_ext_unit {
- struct counter_count *count;
- const struct counter_count_ext *ext;
-};
-
-static ssize_t counter_count_ext_show(struct device *dev,
- struct device_attribute *attr, char *buf)
-{
- const struct counter_device_attr *const devattr = to_counter_attr(attr);
- const struct counter_count_ext_unit *const comp = devattr->component;
- const struct counter_count_ext *const ext = comp->ext;
-
- return ext->read(dev_get_drvdata(dev), comp->count, ext->priv, buf);
-}
-
-static ssize_t counter_count_ext_store(struct device *dev,
- struct device_attribute *attr,
- const char *buf, size_t len)
-{
- const struct counter_device_attr *const devattr = to_counter_attr(attr);
- const struct counter_count_ext_unit *const comp = devattr->component;
- const struct counter_count_ext *const ext = comp->ext;
-
- return ext->write(dev_get_drvdata(dev), comp->count, ext->priv, buf,
- len);
-}
-
-static int counter_count_ext_register(
- struct counter_device_attr_group *const group,
- struct counter_count *const count)
-{
- size_t i;
- const struct counter_count_ext *ext;
- struct counter_count_ext_unit *count_ext_comp;
- struct counter_attr_parm parm;
- int err;
-
- /* Create an attribute for each extension */
- for (i = 0 ; i < count->num_ext; i++) {
- ext = count->ext + i;
-
- /* Allocate count_ext attribute component */
- count_ext_comp = kmalloc(sizeof(*count_ext_comp), GFP_KERNEL);
- if (!count_ext_comp) {
- err = -ENOMEM;
- goto err_free_attr_list;
- }
- count_ext_comp->count = count;
- count_ext_comp->ext = ext;
-
- /* Allocate count_ext attribute */
- parm.group = group;
- parm.prefix = "";
- parm.name = ext->name;
- parm.show = (ext->read) ? counter_count_ext_show : NULL;
- parm.store = (ext->write) ? counter_count_ext_store : NULL;
- parm.component = count_ext_comp;
- err = counter_attribute_create(&parm);
- if (err) {
- kfree(count_ext_comp);
- goto err_free_attr_list;
- }
- }
-
- return 0;
-
-err_free_attr_list:
- counter_device_attr_list_free(&group->attr_list);
- return err;
-}
-
-struct counter_func_avail_unit {
- const enum counter_count_function *functions_list;
- size_t num_functions;
-};
-
-static ssize_t counter_count_function_available_show(struct device *dev,
- struct device_attribute *attr, char *buf)
-{
- const struct counter_device_attr *const devattr = to_counter_attr(attr);
- const struct counter_func_avail_unit *const component = devattr->component;
- const enum counter_count_function *const func_list = component->functions_list;
- const size_t num_functions = component->num_functions;
- size_t i;
- enum counter_count_function function;
- ssize_t len = 0;
-
- for (i = 0; i < num_functions; i++) {
- function = func_list[i];
- len += sprintf(buf + len, "%s\n",
- counter_count_function_str[function]);
- }
-
- return len;
-}
-
-static int counter_count_attributes_create(
- struct counter_device_attr_group *const group,
- const struct counter_device *const counter,
- struct counter_count *const count)
-{
- struct counter_count_unit *count_comp;
- struct counter_attr_parm parm;
- int err;
- struct counter_count_unit *func_comp;
- struct counter_func_avail_unit *avail_comp;
-
- /* Allocate count attribute component */
- count_comp = kmalloc(sizeof(*count_comp), GFP_KERNEL);
- if (!count_comp)
- return -ENOMEM;
- count_comp->count = count;
-
- /* Create main Count attribute */
- parm.group = group;
- parm.prefix = "";
- parm.name = "count";
- parm.show = (counter->ops->count_read) ? counter_count_show : NULL;
- parm.store = (counter->ops->count_write) ? counter_count_store : NULL;
- parm.component = count_comp;
- err = counter_attribute_create(&parm);
- if (err) {
- kfree(count_comp);
- return err;
- }
-
- /* Allocate function attribute component */
- func_comp = kmalloc(sizeof(*func_comp), GFP_KERNEL);
- if (!func_comp) {
- err = -ENOMEM;
- goto err_free_attr_list;
- }
- func_comp->count = count;
-
- /* Create Count function attribute */
- parm.group = group;
- parm.prefix = "";
- parm.name = "function";
- parm.show = (counter->ops->function_get) ? counter_function_show : NULL;
- parm.store = (counter->ops->function_set) ? counter_function_store : NULL;
- parm.component = func_comp;
- err = counter_attribute_create(&parm);
- if (err) {
- kfree(func_comp);
- goto err_free_attr_list;
- }
-
- /* Allocate function available attribute component */
- avail_comp = kmalloc(sizeof(*avail_comp), GFP_KERNEL);
- if (!avail_comp) {
- err = -ENOMEM;
- goto err_free_attr_list;
- }
- avail_comp->functions_list = count->functions_list;
- avail_comp->num_functions = count->num_functions;
-
- /* Create Count function_available attribute */
- parm.group = group;
- parm.prefix = "";
- parm.name = "function_available";
- parm.show = counter_count_function_available_show;
- parm.store = NULL;
- parm.component = avail_comp;
- err = counter_attribute_create(&parm);
- if (err) {
- kfree(avail_comp);
- goto err_free_attr_list;
- }
-
- /* Create Count name attribute */
- err = counter_name_attribute_create(group, count->name);
- if (err)
- goto err_free_attr_list;
-
- /* Register Count extension attributes */
- err = counter_count_ext_register(group, count);
- if (err)
- goto err_free_attr_list;
-
- return 0;
-
-err_free_attr_list:
- counter_device_attr_list_free(&group->attr_list);
- return err;
-}
-
-static int counter_counts_register(
- struct counter_device_attr_group *const groups_list,
- const struct counter_device *const counter)
-{
- size_t i;
- struct counter_count *count;
- const char *name;
- int err;
-
- /* Register each Count */
- for (i = 0; i < counter->num_counts; i++) {
- count = counter->counts + i;
-
- /* Generate Count attribute directory name */
- name = kasprintf(GFP_KERNEL, "count%d", count->id);
- if (!name) {
- err = -ENOMEM;
- goto err_free_attr_groups;
- }
- groups_list[i].attr_group.name = name;
-
- /* Register the Synapses associated with each Count */
- err = counter_synapses_register(groups_list + i, counter, count,
- name);
- if (err)
- goto err_free_attr_groups;
-
- /* Create all attributes associated with Count */
- err = counter_count_attributes_create(groups_list + i, counter,
- count);
- if (err)
- goto err_free_attr_groups;
- }
-
- return 0;
-
-err_free_attr_groups:
- do {
- kfree(groups_list[i].attr_group.name);
- counter_device_attr_list_free(&groups_list[i].attr_list);
- } while (i--);
- return err;
-}
-
-struct counter_size_unit {
- size_t size;
-};
-
-static ssize_t counter_device_attr_size_show(struct device *dev,
- struct device_attribute *attr,
- char *buf)
-{
- const struct counter_size_unit *const comp = to_counter_attr(attr)->component;
-
- return sprintf(buf, "%zu\n", comp->size);
-}
-
-static int counter_size_attribute_create(
- struct counter_device_attr_group *const group,
- const size_t size, const char *const name)
-{
- struct counter_size_unit *size_comp;
- struct counter_attr_parm parm;
- int err;
-
- /* Allocate size attribute component */
- size_comp = kmalloc(sizeof(*size_comp), GFP_KERNEL);
- if (!size_comp)
- return -ENOMEM;
- size_comp->size = size;
-
- parm.group = group;
- parm.prefix = "";
- parm.name = name;
- parm.show = counter_device_attr_size_show;
- parm.store = NULL;
- parm.component = size_comp;
- err = counter_attribute_create(&parm);
- if (err)
- goto err_free_size_comp;
-
- return 0;
-
-err_free_size_comp:
- kfree(size_comp);
- return err;
-}
-
-struct counter_ext_unit {
- const struct counter_device_ext *ext;
-};
-
-static ssize_t counter_device_ext_show(struct device *dev,
- struct device_attribute *attr, char *buf)
-{
- const struct counter_device_attr *const devattr = to_counter_attr(attr);
- const struct counter_ext_unit *const component = devattr->component;
- const struct counter_device_ext *const ext = component->ext;
-
- return ext->read(dev_get_drvdata(dev), ext->priv, buf);
-}
-
-static ssize_t counter_device_ext_store(struct device *dev,
- struct device_attribute *attr,
- const char *buf, size_t len)
-{
- const struct counter_device_attr *const devattr = to_counter_attr(attr);
- const struct counter_ext_unit *const component = devattr->component;
- const struct counter_device_ext *const ext = component->ext;
-
- return ext->write(dev_get_drvdata(dev), ext->priv, buf, len);
-}
-
-static int counter_device_ext_register(
- struct counter_device_attr_group *const group,
- struct counter_device *const counter)
-{
- size_t i;
- struct counter_ext_unit *ext_comp;
- struct counter_attr_parm parm;
- int err;
-
- /* Create an attribute for each extension */
- for (i = 0 ; i < counter->num_ext; i++) {
- /* Allocate extension attribute component */
- ext_comp = kmalloc(sizeof(*ext_comp), GFP_KERNEL);
- if (!ext_comp) {
- err = -ENOMEM;
- goto err_free_attr_list;
- }
-
- ext_comp->ext = counter->ext + i;
-
- /* Allocate extension attribute */
- parm.group = group;
- parm.prefix = "";
- parm.name = counter->ext[i].name;
- parm.show = (counter->ext[i].read) ? counter_device_ext_show : NULL;
- parm.store = (counter->ext[i].write) ? counter_device_ext_store : NULL;
- parm.component = ext_comp;
- err = counter_attribute_create(&parm);
- if (err) {
- kfree(ext_comp);
- goto err_free_attr_list;
- }
- }
-
- return 0;
-
-err_free_attr_list:
- counter_device_attr_list_free(&group->attr_list);
- return err;
-}
-
-static int counter_global_attr_register(
- struct counter_device_attr_group *const group,
- struct counter_device *const counter)
-{
- int err;
-
- /* Create name attribute */
- err = counter_name_attribute_create(group, counter->name);
- if (err)
- return err;
-
- /* Create num_counts attribute */
- err = counter_size_attribute_create(group, counter->num_counts,
- "num_counts");
- if (err)
- goto err_free_attr_list;
-
- /* Create num_signals attribute */
- err = counter_size_attribute_create(group, counter->num_signals,
- "num_signals");
- if (err)
- goto err_free_attr_list;
-
- /* Register Counter device extension attributes */
- err = counter_device_ext_register(group, counter);
- if (err)
- goto err_free_attr_list;
-
- return 0;
-
-err_free_attr_list:
- counter_device_attr_list_free(&group->attr_list);
- return err;
-}
-
-static void counter_device_groups_list_free(
- struct counter_device_attr_group *const groups_list,
- const size_t num_groups)
-{
- struct counter_device_attr_group *group;
- size_t i;
-
- /* loop through all attribute groups (signals, counts, global, etc.) */
- for (i = 0; i < num_groups; i++) {
- group = groups_list + i;
-
- /* free all attribute group and associated attributes memory */
- kfree(group->attr_group.name);
- kfree(group->attr_group.attrs);
- counter_device_attr_list_free(&group->attr_list);
- }
-
- kfree(groups_list);
-}
-
-static int counter_device_groups_list_prepare(
- struct counter_device *const counter)
-{
- const size_t total_num_groups =
- counter->num_signals + counter->num_counts + 1;
- struct counter_device_attr_group *groups_list;
- size_t i;
- int err;
- size_t num_groups = 0;
-
- /* Allocate space for attribute groups (signals, counts, and ext) */
- groups_list = kcalloc(total_num_groups, sizeof(*groups_list),
- GFP_KERNEL);
- if (!groups_list)
- return -ENOMEM;
-
- /* Initialize attribute lists */
- for (i = 0; i < total_num_groups; i++)
- INIT_LIST_HEAD(&groups_list[i].attr_list);
-
- /* Register Signals */
- err = counter_signals_register(groups_list, counter);
- if (err)
- goto err_free_groups_list;
- num_groups += counter->num_signals;
-
- /* Register Counts and respective Synapses */
- err = counter_counts_register(groups_list + num_groups, counter);
- if (err)
- goto err_free_groups_list;
- num_groups += counter->num_counts;
-
- /* Register Counter global attributes */
- err = counter_global_attr_register(groups_list + num_groups, counter);
- if (err)
- goto err_free_groups_list;
- num_groups++;
-
- /* Store groups_list in device_state */
- counter->device_state->groups_list = groups_list;
- counter->device_state->num_groups = num_groups;
-
- return 0;
-
-err_free_groups_list:
- counter_device_groups_list_free(groups_list, num_groups);
- return err;
-}
-
-static int counter_device_groups_prepare(
- struct counter_device_state *const device_state)
-{
- size_t i, j;
- struct counter_device_attr_group *group;
- int err;
- struct counter_device_attr *p;
-
- /* Allocate attribute groups for association with device */
- device_state->groups = kcalloc(device_state->num_groups + 1,
- sizeof(*device_state->groups),
- GFP_KERNEL);
- if (!device_state->groups)
- return -ENOMEM;
-
- /* Prepare each group of attributes for association */
- for (i = 0; i < device_state->num_groups; i++) {
- group = device_state->groups_list + i;
-
- /* Allocate space for attribute pointers in attribute group */
- group->attr_group.attrs = kcalloc(group->num_attr + 1,
- sizeof(*group->attr_group.attrs), GFP_KERNEL);
- if (!group->attr_group.attrs) {
- err = -ENOMEM;
- goto err_free_groups;
- }
-
- /* Add attribute pointers to attribute group */
- j = 0;
- list_for_each_entry(p, &group->attr_list, l)
- group->attr_group.attrs[j++] = &p->dev_attr.attr;
-
- /* Group attributes in attribute group */
- device_state->groups[i] = &group->attr_group;
- }
- /* Associate attributes with device */
- device_state->dev.groups = device_state->groups;
-
- return 0;
-
-err_free_groups:
- do {
- group = device_state->groups_list + i;
- kfree(group->attr_group.attrs);
- group->attr_group.attrs = NULL;
- } while (i--);
- kfree(device_state->groups);
- return err;
-}
-
-/* Provides a unique ID for each counter device */
-static DEFINE_IDA(counter_ida);
-
-static void counter_device_release(struct device *dev)
-{
- struct counter_device *const counter = dev_get_drvdata(dev);
- struct counter_device_state *const device_state = counter->device_state;
-
- kfree(device_state->groups);
- counter_device_groups_list_free(device_state->groups_list,
- device_state->num_groups);
- ida_simple_remove(&counter_ida, device_state->id);
- kfree(device_state);
-}
-
-static struct device_type counter_device_type = {
- .name = "counter_device",
- .release = counter_device_release
-};
-
-static struct bus_type counter_bus_type = {
- .name = "counter"
-};
-
-/**
- * counter_register - register Counter to the system
- * @counter: pointer to Counter to register
- *
- * This function registers a Counter to the system. A sysfs "counter" directory
- * will be created and populated with sysfs attributes correlating with the
- * Counter Signals, Synapses, and Counts respectively.
- */
-int counter_register(struct counter_device *const counter)
-{
- struct counter_device_state *device_state;
- int err;
-
- /* Allocate internal state container for Counter device */
- device_state = kzalloc(sizeof(*device_state), GFP_KERNEL);
- if (!device_state)
- return -ENOMEM;
- counter->device_state = device_state;
-
- /* Acquire unique ID */
- device_state->id = ida_simple_get(&counter_ida, 0, 0, GFP_KERNEL);
- if (device_state->id < 0) {
- err = device_state->id;
- goto err_free_device_state;
- }
-
- /* Configure device structure for Counter */
- device_state->dev.type = &counter_device_type;
- device_state->dev.bus = &counter_bus_type;
- if (counter->parent) {
- device_state->dev.parent = counter->parent;
- device_state->dev.of_node = counter->parent->of_node;
- }
- dev_set_name(&device_state->dev, "counter%d", device_state->id);
- device_initialize(&device_state->dev);
- dev_set_drvdata(&device_state->dev, counter);
-
- /* Prepare device attributes */
- err = counter_device_groups_list_prepare(counter);
- if (err)
- goto err_free_id;
-
- /* Organize device attributes to groups and match to device */
- err = counter_device_groups_prepare(device_state);
- if (err)
- goto err_free_groups_list;
-
- /* Add device to system */
- err = device_add(&device_state->dev);
- if (err)
- goto err_free_groups;
-
- return 0;
-
-err_free_groups:
- kfree(device_state->groups);
-err_free_groups_list:
- counter_device_groups_list_free(device_state->groups_list,
- device_state->num_groups);
-err_free_id:
- ida_simple_remove(&counter_ida, device_state->id);
-err_free_device_state:
- kfree(device_state);
- return err;
-}
-EXPORT_SYMBOL_GPL(counter_register);
-
-/**
- * counter_unregister - unregister Counter from the system
- * @counter: pointer to Counter to unregister
- *
- * The Counter is unregistered from the system; all allocated memory is freed.
- */
-void counter_unregister(struct counter_device *const counter)
-{
- if (counter)
- device_del(&counter->device_state->dev);
-}
-EXPORT_SYMBOL_GPL(counter_unregister);
-
-static void devm_counter_unreg(struct device *dev, void *res)
-{
- counter_unregister(*(struct counter_device **)res);
-}
-
-/**
- * devm_counter_register - Resource-managed counter_register
- * @dev: device to allocate counter_device for
- * @counter: pointer to Counter to register
- *
- * Managed counter_register. The Counter registered with this function is
- * automatically unregistered on driver detach. This function calls
- * counter_register internally. Refer to that function for more information.
- *
- * If an Counter registered with this function needs to be unregistered
- * separately, devm_counter_unregister must be used.
- *
- * RETURNS:
- * 0 on success, negative error number on failure.
- */
-int devm_counter_register(struct device *dev,
- struct counter_device *const counter)
-{
- struct counter_device **ptr;
- int ret;
-
- ptr = devres_alloc(devm_counter_unreg, sizeof(*ptr), GFP_KERNEL);
- if (!ptr)
- return -ENOMEM;
-
- ret = counter_register(counter);
- if (!ret) {
- *ptr = counter;
- devres_add(dev, ptr);
- } else {
- devres_free(ptr);
- }
-
- return ret;
-}
-EXPORT_SYMBOL_GPL(devm_counter_register);
-
-static int devm_counter_match(struct device *dev, void *res, void *data)
-{
- struct counter_device **r = res;
-
- if (!r || !*r) {
- WARN_ON(!r || !*r);
- return 0;
- }
-
- return *r == data;
-}
-
-/**
- * devm_counter_unregister - Resource-managed counter_unregister
- * @dev: device this counter_device belongs to
- * @counter: pointer to Counter associated with the device
- *
- * Unregister Counter registered with devm_counter_register.
- */
-void devm_counter_unregister(struct device *dev,
- struct counter_device *const counter)
-{
- int rc;
-
- rc = devres_release(dev, devm_counter_unreg, devm_counter_match,
- counter);
- WARN_ON(rc);
-}
-EXPORT_SYMBOL_GPL(devm_counter_unregister);
-
-static int __init counter_init(void)
-{
- return bus_register(&counter_bus_type);
-}
-
-static void __exit counter_exit(void)
-{
- bus_unregister(&counter_bus_type);
-}
-
-subsys_initcall(counter_init);
-module_exit(counter_exit);
-
-MODULE_AUTHOR("William Breathitt Gray <vilhelm.gray@gmail.com>");
-MODULE_DESCRIPTION("Generic Counter interface");
-MODULE_LICENSE("GPL v2");
diff --git a/drivers/counter/ftm-quaddec.c b/drivers/counter/ftm-quaddec.c
index c2b3fdfd8b77..71a0f7131237 100644
--- a/drivers/counter/ftm-quaddec.c
+++ b/drivers/counter/ftm-quaddec.c
@@ -14,6 +14,7 @@
#include <linux/mutex.h>
#include <linux/counter.h>
#include <linux/bitfield.h>
+#include <linux/types.h>
#define FTM_FIELD_UPDATE(ftm, offset, mask, val) \
({ \
@@ -115,8 +116,7 @@ static void ftm_quaddec_disable(void *ftm)
}
static int ftm_quaddec_get_prescaler(struct counter_device *counter,
- struct counter_count *count,
- size_t *cnt_mode)
+ struct counter_count *count, u8 *cnt_mode)
{
struct ftm_quaddec *ftm = counter->priv;
uint32_t scflags;
@@ -129,8 +129,7 @@ static int ftm_quaddec_get_prescaler(struct counter_device *counter,
}
static int ftm_quaddec_set_prescaler(struct counter_device *counter,
- struct counter_count *count,
- size_t cnt_mode)
+ struct counter_count *count, u8 cnt_mode)
{
struct ftm_quaddec *ftm = counter->priv;
@@ -151,34 +150,21 @@ static const char * const ftm_quaddec_prescaler[] = {
"1", "2", "4", "8", "16", "32", "64", "128"
};
-static struct counter_count_enum_ext ftm_quaddec_prescaler_enum = {
- .items = ftm_quaddec_prescaler,
- .num_items = ARRAY_SIZE(ftm_quaddec_prescaler),
- .get = ftm_quaddec_get_prescaler,
- .set = ftm_quaddec_set_prescaler
-};
-
-enum ftm_quaddec_synapse_action {
- FTM_QUADDEC_SYNAPSE_ACTION_BOTH_EDGES,
-};
-
-static enum counter_synapse_action ftm_quaddec_synapse_actions[] = {
- [FTM_QUADDEC_SYNAPSE_ACTION_BOTH_EDGES] =
+static const u8 ftm_quaddec_synapse_actions[] = {
COUNTER_SYNAPSE_ACTION_BOTH_EDGES
};
enum ftm_quaddec_count_function {
- FTM_QUADDEC_COUNT_ENCODER_MODE_1,
+ FTM_QUADDEC_COUNT_ENCODER_MODE_1 = COUNTER_COUNT_FUNCTION_QUADRATURE_X4,
};
-static const enum counter_count_function ftm_quaddec_count_functions[] = {
- [FTM_QUADDEC_COUNT_ENCODER_MODE_1] =
- COUNTER_COUNT_FUNCTION_QUADRATURE_X4
+static const u8 ftm_quaddec_count_functions[] = {
+ FTM_QUADDEC_COUNT_ENCODER_MODE_1
};
static int ftm_quaddec_count_read(struct counter_device *counter,
struct counter_count *count,
- unsigned long *val)
+ u64 *val)
{
struct ftm_quaddec *const ftm = counter->priv;
uint32_t cntval;
@@ -192,7 +178,7 @@ static int ftm_quaddec_count_read(struct counter_device *counter,
static int ftm_quaddec_count_write(struct counter_device *counter,
struct counter_count *count,
- const unsigned long val)
+ const u64 val)
{
struct ftm_quaddec *const ftm = counter->priv;
@@ -208,7 +194,7 @@ static int ftm_quaddec_count_write(struct counter_device *counter,
static int ftm_quaddec_count_function_get(struct counter_device *counter,
struct counter_count *count,
- size_t *function)
+ u8 *function)
{
*function = FTM_QUADDEC_COUNT_ENCODER_MODE_1;
@@ -218,20 +204,13 @@ static int ftm_quaddec_count_function_get(struct counter_device *counter,
static int ftm_quaddec_action_get(struct counter_device *counter,
struct counter_count *count,
struct counter_synapse *synapse,
- size_t *action)
+ u8 *action)
{
- *action = FTM_QUADDEC_SYNAPSE_ACTION_BOTH_EDGES;
+ *action = COUNTER_SYNAPSE_ACTION_BOTH_EDGES;
return 0;
}
-static const struct counter_ops ftm_quaddec_cnt_ops = {
- .count_read = ftm_quaddec_count_read,
- .count_write = ftm_quaddec_count_write,
- .function_get = ftm_quaddec_count_function_get,
- .action_get = ftm_quaddec_action_get,
-};
-
static struct counter_signal ftm_quaddec_signals[] = {
{
.id = 0,
@@ -256,9 +235,12 @@ static struct counter_synapse ftm_quaddec_count_synapses[] = {
}
};
-static const struct counter_count_ext ftm_quaddec_count_ext[] = {
- COUNTER_COUNT_ENUM("prescaler", &ftm_quaddec_prescaler_enum),
- COUNTER_COUNT_ENUM_AVAILABLE("prescaler", &ftm_quaddec_prescaler_enum),
+static DEFINE_COUNTER_ENUM(ftm_quaddec_prescaler_enum, ftm_quaddec_prescaler);
+
+static struct counter_data ftm_quaddec_count_ext[] = {
+ COUNTER_DATA_COUNT_ENUM("prescaler", ftm_quaddec_get_prescaler,
+ ftm_quaddec_set_prescaler,
+ ftm_quaddec_prescaler_enum),
};
static struct counter_count ftm_quaddec_counts = {
@@ -302,7 +284,10 @@ static int ftm_quaddec_probe(struct platform_device *pdev)
}
ftm->counter.name = dev_name(&pdev->dev);
ftm->counter.parent = &pdev->dev;
- ftm->counter.ops = &ftm_quaddec_cnt_ops;
+ ftm->counter.count_read = ftm_quaddec_count_read;
+ ftm->counter.count_write = ftm_quaddec_count_write;
+ ftm->counter.function_read = ftm_quaddec_count_function_get;
+ ftm->counter.action_read = ftm_quaddec_action_get;
ftm->counter.counts = &ftm_quaddec_counts;
ftm->counter.num_counts = 1;
ftm->counter.signals = ftm_quaddec_signals;
diff --git a/drivers/counter/stm32-lptimer-cnt.c b/drivers/counter/stm32-lptimer-cnt.c
index fd6828e2d34f..a37c2456d33a 100644
--- a/drivers/counter/stm32-lptimer-cnt.c
+++ b/drivers/counter/stm32-lptimer-cnt.c
@@ -17,6 +17,7 @@
#include <linux/module.h>
#include <linux/pinctrl/consumer.h>
#include <linux/platform_device.h>
+#include <linux/types.h>
struct stm32_lptim_cnt {
struct counter_device counter;
@@ -352,32 +353,46 @@ static const struct iio_chan_spec stm32_lptim_cnt_channels = {
* @STM32_LPTIM_ENCODER_BOTH_EDGE: count on both edges (IN1 & IN2 quadrature)
*/
enum stm32_lptim_cnt_function {
- STM32_LPTIM_COUNTER_INCREASE,
- STM32_LPTIM_ENCODER_BOTH_EDGE,
+ STM32_LPTIM_COUNTER_INCREASE = COUNTER_COUNT_FUNCTION_INCREASE,
+ STM32_LPTIM_ENCODER_BOTH_EDGE = COUNTER_COUNT_FUNCTION_QUADRATURE_X4,
};
-static enum counter_count_function stm32_lptim_cnt_functions[] = {
- [STM32_LPTIM_COUNTER_INCREASE] = COUNTER_COUNT_FUNCTION_INCREASE,
- [STM32_LPTIM_ENCODER_BOTH_EDGE] = COUNTER_COUNT_FUNCTION_QUADRATURE_X4,
+static u8 stm32_lptim_cnt_functions[] = {
+ STM32_LPTIM_COUNTER_INCREASE,
+ STM32_LPTIM_ENCODER_BOTH_EDGE,
};
enum stm32_lptim_synapse_action {
+ /* Index must match with stm32_lptim_cnt_polarity[] (priv->polarity) */
STM32_LPTIM_SYNAPSE_ACTION_RISING_EDGE,
STM32_LPTIM_SYNAPSE_ACTION_FALLING_EDGE,
STM32_LPTIM_SYNAPSE_ACTION_BOTH_EDGES,
STM32_LPTIM_SYNAPSE_ACTION_NONE,
};
-static enum counter_synapse_action stm32_lptim_cnt_synapse_actions[] = {
- /* Index must match with stm32_lptim_cnt_polarity[] (priv->polarity) */
+static const enum stm32_lptim_synapse_action stm32_lptim_c2l_actions_map[] = {
+ [COUNTER_SYNAPSE_ACTION_RISING_EDGE] = STM32_LPTIM_SYNAPSE_ACTION_RISING_EDGE,
+ [COUNTER_SYNAPSE_ACTION_FALLING_EDGE] = STM32_LPTIM_SYNAPSE_ACTION_FALLING_EDGE,
+ [COUNTER_SYNAPSE_ACTION_BOTH_EDGES] = STM32_LPTIM_SYNAPSE_ACTION_BOTH_EDGES,
+ [COUNTER_SYNAPSE_ACTION_NONE] = STM32_LPTIM_SYNAPSE_ACTION_NONE,
+};
+
+static const u8 stm32_lptim_l2c_actions_map[] = {
[STM32_LPTIM_SYNAPSE_ACTION_RISING_EDGE] = COUNTER_SYNAPSE_ACTION_RISING_EDGE,
[STM32_LPTIM_SYNAPSE_ACTION_FALLING_EDGE] = COUNTER_SYNAPSE_ACTION_FALLING_EDGE,
[STM32_LPTIM_SYNAPSE_ACTION_BOTH_EDGES] = COUNTER_SYNAPSE_ACTION_BOTH_EDGES,
[STM32_LPTIM_SYNAPSE_ACTION_NONE] = COUNTER_SYNAPSE_ACTION_NONE,
};
+static const u8 stm32_lptim_cnt_synapse_actions[] = {
+ COUNTER_SYNAPSE_ACTION_RISING_EDGE,
+ COUNTER_SYNAPSE_ACTION_FALLING_EDGE,
+ COUNTER_SYNAPSE_ACTION_BOTH_EDGES,
+ COUNTER_SYNAPSE_ACTION_NONE,
+};
+
static int stm32_lptim_cnt_read(struct counter_device *counter,
- struct counter_count *count, unsigned long *val)
+ struct counter_count *count, u64 *val)
{
struct stm32_lptim_cnt *const priv = counter->priv;
u32 cnt;
@@ -394,7 +409,7 @@ static int stm32_lptim_cnt_read(struct counter_device *counter,
static int stm32_lptim_cnt_function_get(struct counter_device *counter,
struct counter_count *count,
- size_t *function)
+ u8 *function)
{
struct stm32_lptim_cnt *const priv = counter->priv;
@@ -413,7 +428,7 @@ static int stm32_lptim_cnt_function_get(struct counter_device *counter,
static int stm32_lptim_cnt_function_set(struct counter_device *counter,
struct counter_count *count,
- size_t function)
+ u8 function)
{
struct stm32_lptim_cnt *const priv = counter->priv;
@@ -423,19 +438,20 @@ static int stm32_lptim_cnt_function_set(struct counter_device *counter,
switch (function) {
case STM32_LPTIM_COUNTER_INCREASE:
priv->quadrature_mode = 0;
- return 0;
+ break;
case STM32_LPTIM_ENCODER_BOTH_EDGE:
priv->quadrature_mode = 1;
priv->polarity = STM32_LPTIM_SYNAPSE_ACTION_BOTH_EDGES;
- return 0;
+ break;
+ default: return -EINVAL;
}
- return -EINVAL;
+ return 0;
}
-static ssize_t stm32_lptim_cnt_enable_read(struct counter_device *counter,
- struct counter_count *count,
- void *private, char *buf)
+static int stm32_lptim_cnt_enable_read(struct counter_device *counter,
+ struct counter_count *count,
+ u8 *enable)
{
struct stm32_lptim_cnt *const priv = counter->priv;
int ret;
@@ -444,22 +460,18 @@ static ssize_t stm32_lptim_cnt_enable_read(struct counter_device *counter,
if (ret < 0)
return ret;
- return scnprintf(buf, PAGE_SIZE, "%u\n", ret);
+ *enable = ret;
+
+ return 0;
}
-static ssize_t stm32_lptim_cnt_enable_write(struct counter_device *counter,
- struct counter_count *count,
- void *private,
- const char *buf, size_t len)
+static int stm32_lptim_cnt_enable_write(struct counter_device *counter,
+ struct counter_count *count,
+ u8 enable)
{
struct stm32_lptim_cnt *const priv = counter->priv;
- bool enable;
int ret;
- ret = kstrtobool(buf, &enable);
- if (ret)
- return ret;
-
/* Check nobody uses the timer, or already disabled/enabled */
ret = stm32_lptim_is_enabled(priv);
if ((ret < 0) || (!ret && !enable))
@@ -475,48 +487,51 @@ static ssize_t stm32_lptim_cnt_enable_write(struct counter_device *counter,
if (ret)
return ret;
- return len;
+ return 0;
}
-static ssize_t stm32_lptim_cnt_ceiling_read(struct counter_device *counter,
- struct counter_count *count,
- void *private, char *buf)
+static int stm32_lptim_cnt_ceiling_read(struct counter_device *counter,
+ struct counter_count *count,
+ u64 *ceiling)
{
struct stm32_lptim_cnt *const priv = counter->priv;
- return stm32_lptim_cnt_get_ceiling(priv, buf);
+ *ceiling = priv->ceiling;
+
+ return 0;
}
-static ssize_t stm32_lptim_cnt_ceiling_write(struct counter_device *counter,
- struct counter_count *count,
- void *private,
- const char *buf, size_t len)
+static int stm32_lptim_cnt_ceiling_write(struct counter_device *counter,
+ struct counter_count *count,
+ u64 ceiling)
{
struct stm32_lptim_cnt *const priv = counter->priv;
- return stm32_lptim_cnt_set_ceiling(priv, buf, len);
+ if (ceiling > STM32_LPTIM_MAX_ARR)
+ return -EINVAL;
+
+ if (stm32_lptim_is_enabled(priv))
+ return -EBUSY;
+
+ priv->ceiling = ceiling;
+
+ return 0;
}
-static const struct counter_count_ext stm32_lptim_cnt_ext[] = {
- {
- .name = "enable",
- .read = stm32_lptim_cnt_enable_read,
- .write = stm32_lptim_cnt_enable_write
- },
- {
- .name = "ceiling",
- .read = stm32_lptim_cnt_ceiling_read,
- .write = stm32_lptim_cnt_ceiling_write
- },
+static struct counter_data stm32_lptim_cnt_ext[] = {
+ COUNTER_DATA_ENABLE(stm32_lptim_cnt_enable_read,
+ stm32_lptim_cnt_enable_write),
+ COUNTER_DATA_CEILING(stm32_lptim_cnt_ceiling_read,
+ stm32_lptim_cnt_ceiling_write),
};
static int stm32_lptim_cnt_action_get(struct counter_device *counter,
struct counter_count *count,
struct counter_synapse *synapse,
- size_t *action)
+ u8 *action)
{
struct stm32_lptim_cnt *const priv = counter->priv;
- size_t function;
+ u8 function;
int err;
err = stm32_lptim_cnt_function_get(counter, count, &function);
@@ -527,25 +542,25 @@ static int stm32_lptim_cnt_action_get(struct counter_device *counter,
case STM32_LPTIM_COUNTER_INCREASE:
/* LP Timer acts as up-counter on input 1 */
if (synapse->signal->id == count->synapses[0].signal->id)
- *action = priv->polarity;
+ *action = stm32_lptim_l2c_actions_map[priv->polarity];
else
- *action = STM32_LPTIM_SYNAPSE_ACTION_NONE;
- return 0;
+ *action = COUNTER_SYNAPSE_ACTION_NONE;
+ break;
case STM32_LPTIM_ENCODER_BOTH_EDGE:
- *action = priv->polarity;
- return 0;
+ *action = stm32_lptim_l2c_actions_map[priv->polarity];
+ break;
}
- return -EINVAL;
+ return 0;
}
static int stm32_lptim_cnt_action_set(struct counter_device *counter,
struct counter_count *count,
struct counter_synapse *synapse,
- size_t action)
+ u8 action)
{
struct stm32_lptim_cnt *const priv = counter->priv;
- size_t function;
+ u8 function;
int err;
if (stm32_lptim_is_enabled(priv))
@@ -556,27 +571,15 @@ static int stm32_lptim_cnt_action_set(struct counter_device *counter,
return err;
/* only set polarity when in counter mode (on input 1) */
- if (function == STM32_LPTIM_COUNTER_INCREASE
- && synapse->signal->id == count->synapses[0].signal->id) {
- switch (action) {
- case STM32_LPTIM_SYNAPSE_ACTION_RISING_EDGE:
- case STM32_LPTIM_SYNAPSE_ACTION_FALLING_EDGE:
- case STM32_LPTIM_SYNAPSE_ACTION_BOTH_EDGES:
- priv->polarity = action;
- return 0;
- }
- }
+ if (function != STM32_LPTIM_COUNTER_INCREASE
+ || synapse->signal->id != count->synapses[0].signal->id
+ || action == COUNTER_SYNAPSE_ACTION_NONE)
+ return -EINVAL;
- return -EINVAL;
-}
+ priv->polarity = stm32_lptim_c2l_actions_map[action];
-static const struct counter_ops stm32_lptim_cnt_ops = {
- .count_read = stm32_lptim_cnt_read,
- .function_get = stm32_lptim_cnt_function_get,
- .function_set = stm32_lptim_cnt_function_set,
- .action_get = stm32_lptim_cnt_action_get,
- .action_set = stm32_lptim_cnt_action_set,
-};
+ return 0;
+}
static struct counter_signal stm32_lptim_cnt_signals[] = {
{
@@ -659,7 +662,11 @@ static int stm32_lptim_cnt_probe(struct platform_device *pdev)
/* Initialize Counter device */
priv->counter.name = dev_name(&pdev->dev);
priv->counter.parent = &pdev->dev;
- priv->counter.ops = &stm32_lptim_cnt_ops;
+ priv->counter.count_read = stm32_lptim_cnt_read;
+ priv->counter.function_read = stm32_lptim_cnt_function_get;
+ priv->counter.function_write = stm32_lptim_cnt_function_set;
+ priv->counter.action_read = stm32_lptim_cnt_action_get;
+ priv->counter.action_write = stm32_lptim_cnt_action_set;
if (ddata->has_encoder) {
priv->counter.counts = &stm32_lptim_enc_counts;
priv->counter.num_signals = ARRAY_SIZE(stm32_lptim_cnt_signals);
diff --git a/drivers/counter/stm32-timer-cnt.c b/drivers/counter/stm32-timer-cnt.c
index ef2a974a2f10..502e525836a9 100644
--- a/drivers/counter/stm32-timer-cnt.c
+++ b/drivers/counter/stm32-timer-cnt.c
@@ -13,6 +13,7 @@
#include <linux/module.h>
#include <linux/pinctrl/consumer.h>
#include <linux/platform_device.h>
+#include <linux/types.h>
#define TIM_CCMR_CCXS (BIT(8) | BIT(0))
#define TIM_CCMR_MASK (TIM_CCMR_CC1S | TIM_CCMR_CC2S | \
@@ -45,19 +46,19 @@ struct stm32_timer_cnt {
*/
enum stm32_count_function {
STM32_COUNT_SLAVE_MODE_DISABLED = -1,
+ STM32_COUNT_ENCODER_MODE_1 = COUNTER_COUNT_FUNCTION_QUADRATURE_X2_A,
+ STM32_COUNT_ENCODER_MODE_2 = COUNTER_COUNT_FUNCTION_QUADRATURE_X2_B,
+ STM32_COUNT_ENCODER_MODE_3 = COUNTER_COUNT_FUNCTION_QUADRATURE_X4,
+};
+
+static const u8 stm32_count_functions[] = {
STM32_COUNT_ENCODER_MODE_1,
STM32_COUNT_ENCODER_MODE_2,
STM32_COUNT_ENCODER_MODE_3,
};
-static enum counter_count_function stm32_count_functions[] = {
- [STM32_COUNT_ENCODER_MODE_1] = COUNTER_COUNT_FUNCTION_QUADRATURE_X2_A,
- [STM32_COUNT_ENCODER_MODE_2] = COUNTER_COUNT_FUNCTION_QUADRATURE_X2_B,
- [STM32_COUNT_ENCODER_MODE_3] = COUNTER_COUNT_FUNCTION_QUADRATURE_X4,
-};
-
static int stm32_count_read(struct counter_device *counter,
- struct counter_count *count, unsigned long *val)
+ struct counter_count *count, u64 *val)
{
struct stm32_timer_cnt *const priv = counter->priv;
u32 cnt;
@@ -69,8 +70,7 @@ static int stm32_count_read(struct counter_device *counter,
}
static int stm32_count_write(struct counter_device *counter,
- struct counter_count *count,
- const unsigned long val)
+ struct counter_count *count, const u64 val)
{
struct stm32_timer_cnt *const priv = counter->priv;
@@ -81,8 +81,7 @@ static int stm32_count_write(struct counter_device *counter,
}
static int stm32_count_function_get(struct counter_device *counter,
- struct counter_count *count,
- size_t *function)
+ struct counter_count *count, u8 *function)
{
struct stm32_timer_cnt *const priv = counter->priv;
u32 smcr;
@@ -105,8 +104,7 @@ static int stm32_count_function_get(struct counter_device *counter,
}
static int stm32_count_function_set(struct counter_device *counter,
- struct counter_count *count,
- size_t function)
+ struct counter_count *count, u8 function)
{
struct stm32_timer_cnt *const priv = counter->priv;
u32 cr1, sms;
@@ -146,78 +144,67 @@ static int stm32_count_function_set(struct counter_device *counter,
return 0;
}
-static ssize_t stm32_count_direction_read(struct counter_device *counter,
+static int stm32_count_direction_read(struct counter_device *counter,
struct counter_count *count,
- void *private, char *buf)
+ u8 *direction)
{
struct stm32_timer_cnt *const priv = counter->priv;
- const char *direction;
u32 cr1;
regmap_read(priv->regmap, TIM_CR1, &cr1);
- direction = (cr1 & TIM_CR1_DIR) ? "backward" : "forward";
+ *direction = (cr1 & TIM_CR1_DIR) ? COUNTER_COUNT_DIRECTION_BACKWARD :
+ COUNTER_COUNT_DIRECTION_FORWARD;
- return scnprintf(buf, PAGE_SIZE, "%s\n", direction);
+ return 0;
}
-static ssize_t stm32_count_ceiling_read(struct counter_device *counter,
- struct counter_count *count,
- void *private, char *buf)
+static int stm32_count_ceiling_read(struct counter_device *counter,
+ struct counter_count *count, u64 *ceiling)
{
struct stm32_timer_cnt *const priv = counter->priv;
u32 arr;
regmap_read(priv->regmap, TIM_ARR, &arr);
- return snprintf(buf, PAGE_SIZE, "%u\n", arr);
+ *ceiling = arr;
+
+ return 0;
}
-static ssize_t stm32_count_ceiling_write(struct counter_device *counter,
- struct counter_count *count,
- void *private,
- const char *buf, size_t len)
+static int stm32_count_ceiling_write(struct counter_device *counter,
+ struct counter_count *count, u64 ceiling)
{
struct stm32_timer_cnt *const priv = counter->priv;
- unsigned int ceiling;
- int ret;
- ret = kstrtouint(buf, 0, &ceiling);
- if (ret)
- return ret;
+ if (ceiling != (u32)ceiling)
+ return -ERANGE;
/* TIMx_ARR register shouldn't be buffered (ARPE=0) */
regmap_update_bits(priv->regmap, TIM_CR1, TIM_CR1_ARPE, 0);
regmap_write(priv->regmap, TIM_ARR, ceiling);
priv->ceiling = ceiling;
- return len;
+ return 0;
}
-static ssize_t stm32_count_enable_read(struct counter_device *counter,
- struct counter_count *count,
- void *private, char *buf)
+static int stm32_count_enable_read(struct counter_device *counter,
+ struct counter_count *count, u8 *enable)
{
struct stm32_timer_cnt *const priv = counter->priv;
u32 cr1;
regmap_read(priv->regmap, TIM_CR1, &cr1);
- return scnprintf(buf, PAGE_SIZE, "%d\n", (bool)(cr1 & TIM_CR1_CEN));
+ *enable = cr1 & TIM_CR1_CEN;
+
+ return 0;
}
-static ssize_t stm32_count_enable_write(struct counter_device *counter,
- struct counter_count *count,
- void *private,
- const char *buf, size_t len)
+static int stm32_count_enable_write(struct counter_device *counter,
+ struct counter_count *count, u8 enable)
{
struct stm32_timer_cnt *const priv = counter->priv;
- int err;
u32 cr1;
- bool enable;
-
- err = kstrtobool(buf, &enable);
- if (err)
- return err;
if (enable) {
regmap_read(priv->regmap, TIM_CR1, &cr1);
@@ -236,46 +223,30 @@ static ssize_t stm32_count_enable_write(struct counter_device *counter,
/* Keep enabled state to properly handle low power states */
priv->enabled = enable;
- return len;
+ return 0;
}
-static const struct counter_count_ext stm32_count_ext[] = {
- {
- .name = "direction",
- .read = stm32_count_direction_read,
- },
- {
- .name = "enable",
- .read = stm32_count_enable_read,
- .write = stm32_count_enable_write
- },
- {
- .name = "ceiling",
- .read = stm32_count_ceiling_read,
- .write = stm32_count_ceiling_write
- },
-};
-
-enum stm32_synapse_action {
- STM32_SYNAPSE_ACTION_NONE,
- STM32_SYNAPSE_ACTION_BOTH_EDGES
+static struct counter_data stm32_count_ext[] = {
+ COUNTER_DATA_DIRECTION(stm32_count_direction_read),
+ COUNTER_DATA_ENABLE(stm32_count_enable_read, stm32_count_enable_write),
+ COUNTER_DATA_CEILING(stm32_count_ceiling_read,
+ stm32_count_ceiling_write),
};
-static enum counter_synapse_action stm32_synapse_actions[] = {
- [STM32_SYNAPSE_ACTION_NONE] = COUNTER_SYNAPSE_ACTION_NONE,
- [STM32_SYNAPSE_ACTION_BOTH_EDGES] = COUNTER_SYNAPSE_ACTION_BOTH_EDGES
+static const u8 stm32_synapse_actions[] = {
+ COUNTER_SYNAPSE_ACTION_NONE,
+ COUNTER_SYNAPSE_ACTION_BOTH_EDGES
};
static int stm32_action_get(struct counter_device *counter,
struct counter_count *count,
- struct counter_synapse *synapse,
- size_t *action)
+ struct counter_synapse *synapse, u8 *action)
{
- size_t function;
+ u8 function;
int err;
/* Default action mode (e.g. STM32_COUNT_SLAVE_MODE_DISABLED) */
- *action = STM32_SYNAPSE_ACTION_NONE;
+ *action = COUNTER_SYNAPSE_ACTION_NONE;
err = stm32_count_function_get(counter, count, &function);
if (err)
@@ -285,30 +256,22 @@ static int stm32_action_get(struct counter_device *counter,
case STM32_COUNT_ENCODER_MODE_1:
/* counts up/down on TI1FP1 edge depending on TI2FP2 level */
if (synapse->signal->id == count->synapses[0].signal->id)
- *action = STM32_SYNAPSE_ACTION_BOTH_EDGES;
+ *action = COUNTER_SYNAPSE_ACTION_BOTH_EDGES;
break;
case STM32_COUNT_ENCODER_MODE_2:
/* counts up/down on TI2FP2 edge depending on TI1FP1 level */
if (synapse->signal->id == count->synapses[1].signal->id)
- *action = STM32_SYNAPSE_ACTION_BOTH_EDGES;
+ *action = COUNTER_SYNAPSE_ACTION_BOTH_EDGES;
break;
case STM32_COUNT_ENCODER_MODE_3:
/* counts up/down on both TI1FP1 and TI2FP2 edges */
- *action = STM32_SYNAPSE_ACTION_BOTH_EDGES;
+ *action = COUNTER_SYNAPSE_ACTION_BOTH_EDGES;
break;
}
return 0;
}
-static const struct counter_ops stm32_timer_cnt_ops = {
- .count_read = stm32_count_read,
- .count_write = stm32_count_write,
- .function_get = stm32_count_function_get,
- .function_set = stm32_count_function_set,
- .action_get = stm32_action_get,
-};
-
static struct counter_signal stm32_signals[] = {
{
.id = 0,
@@ -363,7 +326,11 @@ static int stm32_timer_cnt_probe(struct platform_device *pdev)
priv->counter.name = dev_name(dev);
priv->counter.parent = dev;
- priv->counter.ops = &stm32_timer_cnt_ops;
+ priv->counter.count_read = stm32_count_read;
+ priv->counter.count_write = stm32_count_write;
+ priv->counter.function_read = stm32_count_function_get;
+ priv->counter.function_write = stm32_count_function_set;
+ priv->counter.action_read = stm32_action_get;
priv->counter.counts = &stm32_counts;
priv->counter.num_counts = 1;
priv->counter.signals = stm32_signals;
diff --git a/drivers/counter/ti-eqep.c b/drivers/counter/ti-eqep.c
index 1ff07faef27f..7152f0b3c2de 100644
--- a/drivers/counter/ti-eqep.c
+++ b/drivers/counter/ti-eqep.c
@@ -13,6 +13,7 @@
#include <linux/platform_device.h>
#include <linux/pm_runtime.h>
#include <linux/regmap.h>
+#include <linux/types.h>
/* 32-bit registers */
#define QPOSCNT 0x0
@@ -80,12 +81,6 @@ enum {
TI_EQEP_COUNT_FUNC_DOWN_COUNT,
};
-enum {
- TI_EQEP_SYNAPSE_ACTION_BOTH_EDGES,
- TI_EQEP_SYNAPSE_ACTION_RISING_EDGE,
- TI_EQEP_SYNAPSE_ACTION_NONE,
-};
-
struct ti_eqep_cnt {
struct counter_device counter;
struct regmap *regmap32;
@@ -93,7 +88,7 @@ struct ti_eqep_cnt {
};
static int ti_eqep_count_read(struct counter_device *counter,
- struct counter_count *count, unsigned long *val)
+ struct counter_count *count, u64 *val)
{
struct ti_eqep_cnt *priv = counter->priv;
u32 cnt;
@@ -105,7 +100,7 @@ static int ti_eqep_count_read(struct counter_device *counter,
}
static int ti_eqep_count_write(struct counter_device *counter,
- struct counter_count *count, unsigned long val)
+ struct counter_count *count, u64 val)
{
struct ti_eqep_cnt *priv = counter->priv;
u32 max;
@@ -117,33 +112,66 @@ static int ti_eqep_count_write(struct counter_device *counter,
return regmap_write(priv->regmap32, QPOSCNT, val);
}
+static const u8 ti_qep_t2c_functions_map[] = {
+};
+
static int ti_eqep_function_get(struct counter_device *counter,
- struct counter_count *count, size_t *function)
+ struct counter_count *count, u8 *function)
{
struct ti_eqep_cnt *priv = counter->priv;
u32 qdecctl;
regmap_read(priv->regmap16, QDECCTL, &qdecctl);
- *function = (qdecctl & QDECCTL_QSRC) >> QDECCTL_QSRC_SHIFT;
+
+ switch ((qdecctl & QDECCTL_QSRC) >> QDECCTL_QSRC_SHIFT) {
+ case TI_EQEP_COUNT_FUNC_QUAD_COUNT:
+ *function = COUNTER_COUNT_FUNCTION_QUADRATURE_X4;
+ break;
+ case TI_EQEP_COUNT_FUNC_DIR_COUNT:
+ *function = COUNTER_COUNT_FUNCTION_PULSE_DIRECTION;
+ break;
+ case TI_EQEP_COUNT_FUNC_UP_COUNT:
+ *function = COUNTER_COUNT_FUNCTION_INCREASE;
+ break;
+ case TI_EQEP_COUNT_FUNC_DOWN_COUNT:
+ *function = COUNTER_COUNT_FUNCTION_DECREASE;
+ break;
+ }
return 0;
}
static int ti_eqep_function_set(struct counter_device *counter,
- struct counter_count *count, size_t function)
+ struct counter_count *count, u8 function)
{
struct ti_eqep_cnt *priv = counter->priv;
+ unsigned long qsrc;
+
+ switch (function) {
+ case COUNTER_COUNT_FUNCTION_QUADRATURE_X4:
+ qsrc = TI_EQEP_COUNT_FUNC_QUAD_COUNT;
+ break;
+ case COUNTER_COUNT_FUNCTION_PULSE_DIRECTION:
+ qsrc = TI_EQEP_COUNT_FUNC_DIR_COUNT;
+ break;
+ case COUNTER_COUNT_FUNCTION_INCREASE:
+ qsrc = TI_EQEP_COUNT_FUNC_UP_COUNT;
+ break;
+ case COUNTER_COUNT_FUNCTION_DECREASE:
+ qsrc = TI_EQEP_COUNT_FUNC_DOWN_COUNT;
+ break;
+ }
return regmap_write_bits(priv->regmap16, QDECCTL, QDECCTL_QSRC,
- function << QDECCTL_QSRC_SHIFT);
+ qsrc << QDECCTL_QSRC_SHIFT);
}
static int ti_eqep_action_get(struct counter_device *counter,
struct counter_count *count,
- struct counter_synapse *synapse, size_t *action)
+ struct counter_synapse *synapse, u8 *action)
{
struct ti_eqep_cnt *priv = counter->priv;
- size_t function;
+ u8 function;
u32 qdecctl;
int err;
@@ -152,27 +180,27 @@ static int ti_eqep_action_get(struct counter_device *counter,
return err;
switch (function) {
- case TI_EQEP_COUNT_FUNC_QUAD_COUNT:
+ case COUNTER_COUNT_FUNCTION_QUADRATURE_X4:
/* In quadrature mode, the rising and falling edge of both
* QEPA and QEPB trigger QCLK.
*/
- *action = TI_EQEP_SYNAPSE_ACTION_BOTH_EDGES;
+ *action = COUNTER_SYNAPSE_ACTION_BOTH_EDGES;
break;
- case TI_EQEP_COUNT_FUNC_DIR_COUNT:
+ case COUNTER_COUNT_FUNCTION_PULSE_DIRECTION:
/* In direction-count mode only rising edge of QEPA is counted
* and QEPB gives direction.
*/
switch (synapse->signal->id) {
case TI_EQEP_SIGNAL_QEPA:
- *action = TI_EQEP_SYNAPSE_ACTION_RISING_EDGE;
+ *action = COUNTER_SYNAPSE_ACTION_RISING_EDGE;
break;
default:
- *action = TI_EQEP_SYNAPSE_ACTION_NONE;
+ *action = COUNTER_SYNAPSE_ACTION_NONE;
break;
}
break;
- case TI_EQEP_COUNT_FUNC_UP_COUNT:
- case TI_EQEP_COUNT_FUNC_DOWN_COUNT:
+ case COUNTER_COUNT_FUNCTION_INCREASE:
+ case COUNTER_COUNT_FUNCTION_DECREASE:
/* In up/down-count modes only QEPA is counted and QEPB is not
* used.
*/
@@ -183,134 +211,105 @@ static int ti_eqep_action_get(struct counter_device *counter,
return err;
if (qdecctl & QDECCTL_XCR)
- *action = TI_EQEP_SYNAPSE_ACTION_BOTH_EDGES;
+ *action = COUNTER_SYNAPSE_ACTION_BOTH_EDGES;
else
- *action = TI_EQEP_SYNAPSE_ACTION_RISING_EDGE;
+ *action = COUNTER_SYNAPSE_ACTION_RISING_EDGE;
break;
default:
- *action = TI_EQEP_SYNAPSE_ACTION_NONE;
+ *action = COUNTER_SYNAPSE_ACTION_NONE;
break;
}
break;
+ default: return -EINVAL;
}
return 0;
}
-static const struct counter_ops ti_eqep_counter_ops = {
- .count_read = ti_eqep_count_read,
- .count_write = ti_eqep_count_write,
- .function_get = ti_eqep_function_get,
- .function_set = ti_eqep_function_set,
- .action_get = ti_eqep_action_get,
-};
-
-static ssize_t ti_eqep_position_ceiling_read(struct counter_device *counter,
- struct counter_count *count,
- void *ext_priv, char *buf)
+static int ti_eqep_position_ceiling_read(struct counter_device *counter,
+ struct counter_count *count,
+ u64 *ceiling)
{
struct ti_eqep_cnt *priv = counter->priv;
u32 qposmax;
regmap_read(priv->regmap32, QPOSMAX, &qposmax);
- return sprintf(buf, "%u\n", qposmax);
+ *ceiling = qposmax;
+
+ return 0;
}
-static ssize_t ti_eqep_position_ceiling_write(struct counter_device *counter,
- struct counter_count *count,
- void *ext_priv, const char *buf,
- size_t len)
+static int ti_eqep_position_ceiling_write(struct counter_device *counter,
+ struct counter_count *count,
+ u64 ceiling)
{
struct ti_eqep_cnt *priv = counter->priv;
- int err;
- u32 res;
- err = kstrtouint(buf, 0, &res);
- if (err < 0)
- return err;
+ if (ceiling != (u32)ceiling)
+ return -ERANGE;
- regmap_write(priv->regmap32, QPOSMAX, res);
+ regmap_write(priv->regmap32, QPOSMAX, ceiling);
- return len;
+ return 0;
}
-static ssize_t ti_eqep_position_floor_read(struct counter_device *counter,
- struct counter_count *count,
- void *ext_priv, char *buf)
+static int ti_eqep_position_floor_read(struct counter_device *counter,
+ struct counter_count *count, u64 *floor)
{
struct ti_eqep_cnt *priv = counter->priv;
u32 qposinit;
regmap_read(priv->regmap32, QPOSINIT, &qposinit);
- return sprintf(buf, "%u\n", qposinit);
+ *floor = qposinit;
+
+ return 0;
}
-static ssize_t ti_eqep_position_floor_write(struct counter_device *counter,
- struct counter_count *count,
- void *ext_priv, const char *buf,
- size_t len)
+static int ti_eqep_position_floor_write(struct counter_device *counter,
+ struct counter_count *count, u64 floor)
{
struct ti_eqep_cnt *priv = counter->priv;
- int err;
- u32 res;
- err = kstrtouint(buf, 0, &res);
- if (err < 0)
- return err;
+ if (floor != (u32)floor)
+ return -ERANGE;
- regmap_write(priv->regmap32, QPOSINIT, res);
+ regmap_write(priv->regmap32, QPOSINIT, floor);
- return len;
+ return 0;
}
-static ssize_t ti_eqep_position_enable_read(struct counter_device *counter,
- struct counter_count *count,
- void *ext_priv, char *buf)
+static int ti_eqep_position_enable_read(struct counter_device *counter,
+ struct counter_count *count, u8 *enable)
{
struct ti_eqep_cnt *priv = counter->priv;
u32 qepctl;
regmap_read(priv->regmap16, QEPCTL, &qepctl);
- return sprintf(buf, "%u\n", !!(qepctl & QEPCTL_PHEN));
+ *enable = !!(qepctl & QEPCTL_PHEN);
+
+ return 0;
}
-static ssize_t ti_eqep_position_enable_write(struct counter_device *counter,
- struct counter_count *count,
- void *ext_priv, const char *buf,
- size_t len)
+static int ti_eqep_position_enable_write(struct counter_device *counter,
+ struct counter_count *count, u8 enable)
{
struct ti_eqep_cnt *priv = counter->priv;
- int err;
- bool res;
- err = kstrtobool(buf, &res);
- if (err < 0)
- return err;
-
- regmap_write_bits(priv->regmap16, QEPCTL, QEPCTL_PHEN, res ? -1 : 0);
+ regmap_write_bits(priv->regmap16, QEPCTL, QEPCTL_PHEN, enable ? -1 : 0);
- return len;
+ return 0;
}
-static struct counter_count_ext ti_eqep_position_ext[] = {
- {
- .name = "ceiling",
- .read = ti_eqep_position_ceiling_read,
- .write = ti_eqep_position_ceiling_write,
- },
- {
- .name = "floor",
- .read = ti_eqep_position_floor_read,
- .write = ti_eqep_position_floor_write,
- },
- {
- .name = "enable",
- .read = ti_eqep_position_enable_read,
- .write = ti_eqep_position_enable_write,
- },
+static struct counter_data ti_eqep_position_ext[] = {
+ COUNTER_DATA_CEILING(ti_eqep_position_ceiling_read,
+ ti_eqep_position_ceiling_write),
+ COUNTER_DATA_FLOOR(ti_eqep_position_floor_read,
+ ti_eqep_position_floor_write),
+ COUNTER_DATA_ENABLE(ti_eqep_position_enable_read,
+ ti_eqep_position_enable_write),
};
static struct counter_signal ti_eqep_signals[] = {
@@ -324,17 +323,17 @@ static struct counter_signal ti_eqep_signals[] = {
},
};
-static const enum counter_count_function ti_eqep_position_functions[] = {
- [TI_EQEP_COUNT_FUNC_QUAD_COUNT] = COUNTER_COUNT_FUNCTION_QUADRATURE_X4,
- [TI_EQEP_COUNT_FUNC_DIR_COUNT] = COUNTER_COUNT_FUNCTION_PULSE_DIRECTION,
- [TI_EQEP_COUNT_FUNC_UP_COUNT] = COUNTER_COUNT_FUNCTION_INCREASE,
- [TI_EQEP_COUNT_FUNC_DOWN_COUNT] = COUNTER_COUNT_FUNCTION_DECREASE,
+static const u8 ti_eqep_position_functions[] = {
+ COUNTER_COUNT_FUNCTION_QUADRATURE_X4,
+ COUNTER_COUNT_FUNCTION_PULSE_DIRECTION,
+ COUNTER_COUNT_FUNCTION_INCREASE,
+ COUNTER_COUNT_FUNCTION_DECREASE,
};
-static const enum counter_synapse_action ti_eqep_position_synapse_actions[] = {
- [TI_EQEP_SYNAPSE_ACTION_BOTH_EDGES] = COUNTER_SYNAPSE_ACTION_BOTH_EDGES,
- [TI_EQEP_SYNAPSE_ACTION_RISING_EDGE] = COUNTER_SYNAPSE_ACTION_RISING_EDGE,
- [TI_EQEP_SYNAPSE_ACTION_NONE] = COUNTER_SYNAPSE_ACTION_NONE,
+static const u8 ti_eqep_position_synapse_actions[] = {
+ COUNTER_SYNAPSE_ACTION_BOTH_EDGES,
+ COUNTER_SYNAPSE_ACTION_RISING_EDGE,
+ COUNTER_SYNAPSE_ACTION_NONE,
};
static struct counter_synapse ti_eqep_position_synapses[] = {
@@ -406,7 +405,11 @@ static int ti_eqep_probe(struct platform_device *pdev)
priv->counter.name = dev_name(dev);
priv->counter.parent = dev;
- priv->counter.ops = &ti_eqep_counter_ops;
+ priv->counter.count_read = ti_eqep_count_read;
+ priv->counter.count_write = ti_eqep_count_write;
+ priv->counter.function_read = ti_eqep_function_get;
+ priv->counter.function_write = ti_eqep_function_set;
+ priv->counter.action_read = ti_eqep_action_get;
priv->counter.counts = ti_eqep_counts;
priv->counter.num_counts = ARRAY_SIZE(ti_eqep_counts);
priv->counter.signals = ti_eqep_signals;
diff --git a/include/linux/counter.h b/include/linux/counter.h
index 9dbd5df4cd34..3eb567a5884b 100644
--- a/include/linux/counter.h
+++ b/include/linux/counter.h
@@ -6,418 +6,157 @@
#ifndef _COUNTER_H_
#define _COUNTER_H_
-#include <linux/counter_enum.h>
#include <linux/device.h>
+#include <linux/kernel.h>
+#include <linux/list.h>
#include <linux/types.h>
-
-enum counter_count_direction {
- COUNTER_COUNT_DIRECTION_FORWARD = 0,
- COUNTER_COUNT_DIRECTION_BACKWARD
-};
-extern const char *const counter_count_direction_str[2];
-
-enum counter_count_mode {
- COUNTER_COUNT_MODE_NORMAL = 0,
- COUNTER_COUNT_MODE_RANGE_LIMIT,
- COUNTER_COUNT_MODE_NON_RECYCLE,
- COUNTER_COUNT_MODE_MODULO_N
-};
-extern const char *const counter_count_mode_str[4];
+#include <uapi/linux/counter-types.h>
struct counter_device;
+struct counter_count;
+struct counter_synapse;
struct counter_signal;
-/**
- * struct counter_signal_ext - Counter Signal extensions
- * @name: attribute name
- * @read: read callback for this attribute; may be NULL
- * @write: write callback for this attribute; may be NULL
- * @priv: data private to the driver
- */
-struct counter_signal_ext {
+enum counter_data_type {
+ COUNTER_DATA_TYPE_U8,
+ COUNTER_DATA_TYPE_U64,
+ COUNTER_DATA_TYPE_BOOL,
+ COUNTER_DATA_TYPE_COUNT_FUNCTION,
+ COUNTER_DATA_TYPE_SIGNAL,
+ COUNTER_DATA_TYPE_SYNAPSE_ACTION,
+ COUNTER_DATA_TYPE_ENUM,
+ COUNTER_DATA_TYPE_COUNT_DIRECTION,
+ COUNTER_DATA_TYPE_COUNT_MODE,
+};
+
+struct counter_data {
+ enum counter_data_type type;
const char *name;
- ssize_t (*read)(struct counter_device *counter,
- struct counter_signal *signal, void *priv, char *buf);
- ssize_t (*write)(struct counter_device *counter,
- struct counter_signal *signal, void *priv,
- const char *buf, size_t len);
void *priv;
+ union {
+ int (*action_read)(struct counter_device *counter,
+ struct counter_count *count,
+ struct counter_synapse *synapse, u8 *action);
+ int (*device_u8_read)(struct counter_device *counter, u8 *val);
+ int (*count_u8_read)(struct counter_device *counter,
+ struct counter_count *count, u8 *val);
+ int (*signal_u8_read)(struct counter_device *counter,
+ struct counter_signal *signal, u8 *val);
+ int (*device_u64_read)(struct counter_device *counter,
+ u64 *val);
+ int (*count_u64_read)(struct counter_device *counter,
+ struct counter_count *count, u64 *val);
+ int (*signal_u64_read)(struct counter_device *counter,
+ struct counter_signal *signal, u64 *val);
+ };
+ union {
+ int (*action_write)(struct counter_device *counter,
+ struct counter_count *count,
+ struct counter_synapse *synapse, u8 action);
+ int (*device_u8_write)(struct counter_device *counter, u8 val);
+ int (*count_u8_write)(struct counter_device *counter,
+ struct counter_count *count, u8 val);
+ int (*signal_u8_write)(struct counter_device *counter,
+ struct counter_signal *signal, u8 val);
+ int (*device_u64_write)(struct counter_device *counter,
+ u64 val);
+ int (*count_u64_write)(struct counter_device *counter,
+ struct counter_count *count, u64 val);
+ int (*signal_u64_write)(struct counter_device *counter,
+ struct counter_signal *signal, u64 val);
+ };
};
/**
* struct counter_signal - Counter Signal node
- * @id: unique ID used to identify signal
- * @name: device-specific Signal name; ideally, this should match the name
- * as it appears in the datasheet documentation
- * @ext: optional array of Counter Signal extensions
- * @num_ext: number of Counter Signal extensions specified in @ext
- * @priv: optional private data supplied by driver
+ * @id: unique ID used to identify the Signal
+ * @name: device-specific Signal name
+ * @ext: optional array of Signal extensions
+ * @num_ext: number of Signal extensions specified in @ext
*/
struct counter_signal {
int id;
const char *name;
- const struct counter_signal_ext *ext;
+ struct counter_data *ext;
size_t num_ext;
-
- void *priv;
-};
-
-/**
- * struct counter_signal_enum_ext - Signal enum extension attribute
- * @items: Array of strings
- * @num_items: Number of items specified in @items
- * @set: Set callback function; may be NULL
- * @get: Get callback function; may be NULL
- *
- * The counter_signal_enum_ext structure can be used to implement enum style
- * Signal extension attributes. Enum style attributes are those which have a set
- * of strings that map to unsigned integer values. The Generic Counter Signal
- * enum extension helper code takes care of mapping between value and string, as
- * well as generating a "_available" file which contains a list of all available
- * items. The get callback is used to query the currently active item; the index
- * of the item within the respective items array is returned via the 'item'
- * parameter. The set callback is called when the attribute is updated; the
- * 'item' parameter contains the index of the newly activated item within the
- * respective items array.
- */
-struct counter_signal_enum_ext {
- const char * const *items;
- size_t num_items;
- int (*get)(struct counter_device *counter,
- struct counter_signal *signal, size_t *item);
- int (*set)(struct counter_device *counter,
- struct counter_signal *signal, size_t item);
-};
-
-/**
- * COUNTER_SIGNAL_ENUM() - Initialize Signal enum extension
- * @_name: Attribute name
- * @_e: Pointer to a counter_signal_enum_ext structure
- *
- * This should usually be used together with COUNTER_SIGNAL_ENUM_AVAILABLE()
- */
-#define COUNTER_SIGNAL_ENUM(_name, _e) \
-{ \
- .name = (_name), \
- .read = counter_signal_enum_read, \
- .write = counter_signal_enum_write, \
- .priv = (_e) \
-}
-
-/**
- * COUNTER_SIGNAL_ENUM_AVAILABLE() - Initialize Signal enum available extension
- * @_name: Attribute name ("_available" will be appended to the name)
- * @_e: Pointer to a counter_signal_enum_ext structure
- *
- * Creates a read only attribute that lists all the available enum items in a
- * newline separated list. This should usually be used together with
- * COUNTER_SIGNAL_ENUM()
- */
-#define COUNTER_SIGNAL_ENUM_AVAILABLE(_name, _e) \
-{ \
- .name = (_name "_available"), \
- .read = counter_signal_enum_available_read, \
- .priv = (_e) \
-}
-
-enum counter_synapse_action {
- COUNTER_SYNAPSE_ACTION_NONE = 0,
- COUNTER_SYNAPSE_ACTION_RISING_EDGE,
- COUNTER_SYNAPSE_ACTION_FALLING_EDGE,
- COUNTER_SYNAPSE_ACTION_BOTH_EDGES
};
/**
* struct counter_synapse - Counter Synapse node
- * @action: index of current action mode
* @actions_list: array of available action modes
* @num_actions: number of action modes specified in @actions_list
- * @signal: pointer to associated signal
+ * @signal: pointer to the associated Signal
*/
struct counter_synapse {
- size_t action;
- const enum counter_synapse_action *actions_list;
+ const u8 *actions_list;
size_t num_actions;
struct counter_signal *signal;
};
-struct counter_count;
-
-/**
- * struct counter_count_ext - Counter Count extension
- * @name: attribute name
- * @read: read callback for this attribute; may be NULL
- * @write: write callback for this attribute; may be NULL
- * @priv: data private to the driver
- */
-struct counter_count_ext {
- const char *name;
- ssize_t (*read)(struct counter_device *counter,
- struct counter_count *count, void *priv, char *buf);
- ssize_t (*write)(struct counter_device *counter,
- struct counter_count *count, void *priv,
- const char *buf, size_t len);
- void *priv;
-};
-
-enum counter_count_function {
- COUNTER_COUNT_FUNCTION_INCREASE = 0,
- COUNTER_COUNT_FUNCTION_DECREASE,
- COUNTER_COUNT_FUNCTION_PULSE_DIRECTION,
- COUNTER_COUNT_FUNCTION_QUADRATURE_X1_A,
- COUNTER_COUNT_FUNCTION_QUADRATURE_X1_B,
- COUNTER_COUNT_FUNCTION_QUADRATURE_X2_A,
- COUNTER_COUNT_FUNCTION_QUADRATURE_X2_B,
- COUNTER_COUNT_FUNCTION_QUADRATURE_X4
-};
-
/**
* struct counter_count - Counter Count node
- * @id: unique ID used to identify Count
- * @name: device-specific Count name; ideally, this should match
- * the name as it appears in the datasheet documentation
- * @function: index of current function mode
- * @functions_list: array available function modes
+ * @id: unique ID used to identify the Count
+ * @name: device-specific Count name
+ * @functions_list: array of available function modes
* @num_functions: number of function modes specified in @functions_list
- * @synapses: array of synapses for initialization
- * @num_synapses: number of synapses specified in @synapses
- * @ext: optional array of Counter Count extensions
- * @num_ext: number of Counter Count extensions specified in @ext
- * @priv: optional private data supplied by driver
+ * @synapses: array of Synapses for initialization
+ * @num_synapses: number of Synapses specified in @synapses
+ * @ext: optional array of Count extensions
+ * @num_ext: number of Count extensions specified in @ext
*/
struct counter_count {
int id;
const char *name;
- size_t function;
- const enum counter_count_function *functions_list;
+ const u8 *functions_list;
size_t num_functions;
struct counter_synapse *synapses;
size_t num_synapses;
- const struct counter_count_ext *ext;
+ struct counter_data *ext;
size_t num_ext;
-
- void *priv;
-};
-
-/**
- * struct counter_count_enum_ext - Count enum extension attribute
- * @items: Array of strings
- * @num_items: Number of items specified in @items
- * @set: Set callback function; may be NULL
- * @get: Get callback function; may be NULL
- *
- * The counter_count_enum_ext structure can be used to implement enum style
- * Count extension attributes. Enum style attributes are those which have a set
- * of strings that map to unsigned integer values. The Generic Counter Count
- * enum extension helper code takes care of mapping between value and string, as
- * well as generating a "_available" file which contains a list of all available
- * items. The get callback is used to query the currently active item; the index
- * of the item within the respective items array is returned via the 'item'
- * parameter. The set callback is called when the attribute is updated; the
- * 'item' parameter contains the index of the newly activated item within the
- * respective items array.
- */
-struct counter_count_enum_ext {
- const char * const *items;
- size_t num_items;
- int (*get)(struct counter_device *counter, struct counter_count *count,
- size_t *item);
- int (*set)(struct counter_device *counter, struct counter_count *count,
- size_t item);
};
/**
- * COUNTER_COUNT_ENUM() - Initialize Count enum extension
- * @_name: Attribute name
- * @_e: Pointer to a counter_count_enum_ext structure
- *
- * This should usually be used together with COUNTER_COUNT_ENUM_AVAILABLE()
- */
-#define COUNTER_COUNT_ENUM(_name, _e) \
-{ \
- .name = (_name), \
- .read = counter_count_enum_read, \
- .write = counter_count_enum_write, \
- .priv = (_e) \
-}
-
-/**
- * COUNTER_COUNT_ENUM_AVAILABLE() - Initialize Count enum available extension
- * @_name: Attribute name ("_available" will be appended to the name)
- * @_e: Pointer to a counter_count_enum_ext structure
- *
- * Creates a read only attribute that lists all the available enum items in a
- * newline separated list. This should usually be used together with
- * COUNTER_COUNT_ENUM()
- */
-#define COUNTER_COUNT_ENUM_AVAILABLE(_name, _e) \
-{ \
- .name = (_name "_available"), \
- .read = counter_count_enum_available_read, \
- .priv = (_e) \
-}
-
-/**
- * struct counter_device_attr_group - internal container for attribute group
+ * struct counter_attribute_group - internal container for attribute group
* @attr_group: Counter sysfs attributes group
* @attr_list: list to keep track of created Counter sysfs attributes
* @num_attr: number of Counter sysfs attributes
*/
-struct counter_device_attr_group {
+struct counter_attribute_group {
struct attribute_group attr_group;
struct list_head attr_list;
size_t num_attr;
};
-/**
- * struct counter_device_state - internal state container for a Counter device
- * @id: unique ID used to identify the Counter
- * @dev: internal device structure
- * @groups_list: attribute groups list (for Signals, Counts, and ext)
- * @num_groups: number of attribute groups containers
- * @groups: Counter sysfs attribute groups (to populate @dev.groups)
- */
-struct counter_device_state {
- int id;
- struct device dev;
- struct counter_device_attr_group *groups_list;
- size_t num_groups;
- const struct attribute_group **groups;
-};
-
-enum counter_signal_value {
- COUNTER_SIGNAL_LOW = 0,
- COUNTER_SIGNAL_HIGH
-};
-
-/**
- * struct counter_ops - Callbacks from driver
- * @signal_read: optional read callback for Signal attribute. The read
- * value of the respective Signal should be passed back via
- * the val parameter.
- * @count_read: optional read callback for Count attribute. The read
- * value of the respective Count should be passed back via
- * the val parameter.
- * @count_write: optional write callback for Count attribute. The write
- * value for the respective Count is passed in via the val
- * parameter.
- * @function_get: function to get the current count function mode. Returns
- * 0 on success and negative error code on error. The index
- * of the respective Count's returned function mode should
- * be passed back via the function parameter.
- * @function_set: function to set the count function mode. function is the
- * index of the requested function mode from the respective
- * Count's functions_list array.
- * @action_get: function to get the current action mode. Returns 0 on
- * success and negative error code on error. The index of
- * the respective Synapse's returned action mode should be
- * passed back via the action parameter.
- * @action_set: function to set the action mode. action is the index of
- * the requested action mode from the respective Synapse's
- * actions_list array.
- */
-struct counter_ops {
- int (*signal_read)(struct counter_device *counter,
- struct counter_signal *signal,
- enum counter_signal_value *val);
- int (*count_read)(struct counter_device *counter,
- struct counter_count *count, unsigned long *val);
- int (*count_write)(struct counter_device *counter,
- struct counter_count *count, unsigned long val);
- int (*function_get)(struct counter_device *counter,
- struct counter_count *count, size_t *function);
- int (*function_set)(struct counter_device *counter,
- struct counter_count *count, size_t function);
- int (*action_get)(struct counter_device *counter,
- struct counter_count *count,
- struct counter_synapse *synapse, size_t *action);
- int (*action_set)(struct counter_device *counter,
- struct counter_count *count,
- struct counter_synapse *synapse, size_t action);
-};
-
-/**
- * struct counter_device_ext - Counter device extension
- * @name: attribute name
- * @read: read callback for this attribute; may be NULL
- * @write: write callback for this attribute; may be NULL
- * @priv: data private to the driver
- */
-struct counter_device_ext {
- const char *name;
- ssize_t (*read)(struct counter_device *counter, void *priv, char *buf);
- ssize_t (*write)(struct counter_device *counter, void *priv,
- const char *buf, size_t len);
- void *priv;
-};
-
-/**
- * struct counter_device_enum_ext - Counter enum extension attribute
- * @items: Array of strings
- * @num_items: Number of items specified in @items
- * @set: Set callback function; may be NULL
- * @get: Get callback function; may be NULL
- *
- * The counter_device_enum_ext structure can be used to implement enum style
- * Counter extension attributes. Enum style attributes are those which have a
- * set of strings that map to unsigned integer values. The Generic Counter enum
- * extension helper code takes care of mapping between value and string, as well
- * as generating a "_available" file which contains a list of all available
- * items. The get callback is used to query the currently active item; the index
- * of the item within the respective items array is returned via the 'item'
- * parameter. The set callback is called when the attribute is updated; the
- * 'item' parameter contains the index of the newly activated item within the
- * respective items array.
- */
-struct counter_device_enum_ext {
- const char * const *items;
- size_t num_items;
- int (*get)(struct counter_device *counter, size_t *item);
- int (*set)(struct counter_device *counter, size_t item);
-};
-
-/**
- * COUNTER_DEVICE_ENUM() - Initialize Counter enum extension
- * @_name: Attribute name
- * @_e: Pointer to a counter_device_enum_ext structure
- *
- * This should usually be used together with COUNTER_DEVICE_ENUM_AVAILABLE()
- */
-#define COUNTER_DEVICE_ENUM(_name, _e) \
-{ \
- .name = (_name), \
- .read = counter_device_enum_read, \
- .write = counter_device_enum_write, \
- .priv = (_e) \
-}
-
-/**
- * COUNTER_DEVICE_ENUM_AVAILABLE() - Initialize Counter enum available extension
- * @_name: Attribute name ("_available" will be appended to the name)
- * @_e: Pointer to a counter_device_enum_ext structure
- *
- * Creates a read only attribute that lists all the available enum items in a
- * newline separated list. This should usually be used together with
- * COUNTER_DEVICE_ENUM()
- */
-#define COUNTER_DEVICE_ENUM_AVAILABLE(_name, _e) \
-{ \
- .name = (_name "_available"), \
- .read = counter_device_enum_available_read, \
- .priv = (_e) \
-}
-
/**
* struct counter_device - Counter data structure
- * @name: name of the device as it appears in the datasheet
+ * @name: name of the device
* @parent: optional parent device providing the counters
- * @device_state: internal device state container
- * @ops: callbacks from driver
+ * @signal_read: optional read callback for Signals. The read value of
+ * the respective Signal should be passed back via the
+ * value parameter.
+ * @count_read: optional read callback for Counts. The read value of the
+ * respective Count should be passed back via the value
+ * parameter.
+ * @count_write: optional write callback for Counts. The write value for
+ * the respective Count is passed in via the value
+ * parameter.
+ * @function_read: optional read callback the Count function modes. The
+ * read function mode of the respective Count should be
+ * passed back via the function parameter.
+ * @function_write: option write callback for Count function modes. The
+ * function mode to write for the respective Count is
+ * passed in via the function parameter.
+ * @action_read: optional read callback the Synapse action modes. The
+ * read action mode of the respective Synapse should be
+ * passed back via the action parameter.
+ * @action_write: option write callback for Synapse action modes. The
+ * action mode to write for the respective Synapse is
+ * passed in via the action parameter.
* @signals: array of Signals
* @num_signals: number of Signals specified in @signals
* @counts: array of Counts
@@ -425,23 +164,50 @@ struct counter_device_enum_ext {
* @ext: optional array of Counter device extensions
* @num_ext: number of Counter device extensions specified in @ext
* @priv: optional private data supplied by driver
+ * @id: unique ID used to identify the Counter
+ * @dev: internal device structure
+ * @dynamic_names_list: List for dynamic names
+ * @groups_list: attribute groups list (for Signals, Counts, and ext)
+ * @num_groups: number of attribute groups containers
+ * @groups: Counter sysfs attribute groups (to populate @dev.groups)
*/
struct counter_device {
const char *name;
struct device *parent;
- struct counter_device_state *device_state;
- const struct counter_ops *ops;
+ int (*signal_read)(struct counter_device *counter,
+ struct counter_signal *signal, u8 *value);
+ int (*count_read)(struct counter_device *counter,
+ struct counter_count *count, u64 *value);
+ int (*count_write)(struct counter_device *counter,
+ struct counter_count *count, u64 value);
+ int (*function_read)(struct counter_device *counter,
+ struct counter_count *count, u8 *function);
+ int (*function_write)(struct counter_device *counter,
+ struct counter_count *count, u8 function);
+ int (*action_read)(struct counter_device *counter,
+ struct counter_count *count,
+ struct counter_synapse *synapse, u8 *action);
+ int (*action_write)(struct counter_device *counter,
+ struct counter_count *count,
+ struct counter_synapse *synapse, u8 action);
struct counter_signal *signals;
size_t num_signals;
struct counter_count *counts;
size_t num_counts;
- const struct counter_device_ext *ext;
+ struct counter_data *ext;
size_t num_ext;
void *priv;
+
+ int id;
+ struct device dev;
+ struct list_head dynamic_names_list;
+ struct counter_attribute_group *groups_list;
+ size_t num_groups;
+ const struct attribute_group **groups;
};
int counter_register(struct counter_device *const counter);
@@ -451,4 +217,146 @@ int devm_counter_register(struct device *dev,
void devm_counter_unregister(struct device *dev,
struct counter_device *const counter);
+#define COUNTER_DATA_DEVICE_U8(_name, _read, _write) \
+{ \
+ .type = COUNTER_DATA_TYPE_U8, \
+ .name = (_name), \
+ .device_u8_read = (_read), \
+ .device_u8_write = (_write), \
+}
+#define COUNTER_DATA_COUNT_U8(_name, _read, _write) \
+{ \
+ .type = COUNTER_DATA_TYPE_U8, \
+ .name = (_name), \
+ .count_u8_read = (_read), \
+ .count_u8_write = (_write), \
+}
+#define COUNTER_DATA_SIGNAL_U8(_name, _read, _write) \
+{ \
+ .type = COUNTER_DATA_TYPE_U8, \
+ .name = (_name), \
+ .signal_u8_read = (_read), \
+ .signal_u8_write = (_write), \
+}
+
+#define COUNTER_DATA_DEVICE_U64(_name, _read, _write) \
+{ \
+ .type = COUNTER_DATA_TYPE_U64, \
+ .name = (_name), \
+ .device_u64_read = (_read), \
+ .device_u64_write = (_write), \
+}
+#define COUNTER_DATA_COUNT_U64(_name, _read, _write) \
+{ \
+ .type = COUNTER_DATA_TYPE_U64, \
+ .name = (_name), \
+ .count_u64_read = (_read), \
+ .count_u64_write = (_write), \
+}
+#define COUNTER_DATA_SIGNAL_U64(_name, _read, _write) \
+{ \
+ .type = COUNTER_DATA_TYPE_U64, \
+ .name = (_name), \
+ .signal_u64_read = (_read), \
+ .signal_u64_write = (_write), \
+}
+
+#define COUNTER_DATA_DEVICE_BOOL(_name, _read, _write) \
+{ \
+ .type = COUNTER_DATA_TYPE_BOOL, \
+ .name = (_name), \
+ .device_u8_read = (_read), \
+ .device_u8_write = (_write), \
+}
+#define COUNTER_DATA_COUNT_BOOL(_name, _read, _write) \
+{ \
+ .type = COUNTER_DATA_TYPE_BOOL, \
+ .name = (_name), \
+ .count_u8_read = (_read), \
+ .count_u8_write = (_write), \
+}
+#define COUNTER_DATA_SIGNAL_BOOL(_name, _read, _write) \
+{ \
+ .type = COUNTER_DATA_TYPE_BOOL, \
+ .name = (_name), \
+ .signal_u8_read = (_read), \
+ .signal_u8_write = (_write), \
+}
+
+struct counter_available {
+ union {
+ const u8 *items;
+ const char *const *enums;
+ };
+ size_t num_items;
+};
+
+#define DEFINE_COUNTER_AVAILABLE(_name, _items) \
+ struct counter_available _name = { \
+ .items = (_items), \
+ .num_items = ARRAY_SIZE(_items), \
+ }
+
+#define DEFINE_COUNTER_ENUM(_name, _enums) \
+ struct counter_available _name = { \
+ .enums = (_enums), \
+ .num_items = ARRAY_SIZE(_enums), \
+ }
+
+#define COUNTER_DATA_DEVICE_ENUM(_name, _get, _set, _available) \
+{ \
+ .type = COUNTER_DATA_TYPE_ENUM, \
+ .name = (_name), \
+ .device_u8_read = (_get), \
+ .device_u8_write = (_set), \
+ .priv = &(_available), \
+}
+#define COUNTER_DATA_COUNT_ENUM(_name, _get, _set, _available) \
+{ \
+ .type = COUNTER_DATA_TYPE_ENUM, \
+ .name = (_name), \
+ .count_u8_read = (_get), \
+ .count_u8_write = (_set), \
+ .priv = &(_available), \
+}
+#define COUNTER_DATA_SIGNAL_ENUM(_name, _get, _set, _available) \
+{ \
+ .type = COUNTER_DATA_TYPE_ENUM, \
+ .name = (_name), \
+ .signal_u8_read = (_get), \
+ .signal_u8_write = (_set), \
+ .priv = &(_available), \
+}
+
+#define COUNTER_DATA_CEILING(_read, _write) \
+ COUNTER_DATA_COUNT_U64("ceiling", _read, _write)
+
+#define COUNTER_DATA_COUNT_MODE(_read, _write, _available) \
+{ \
+ .type = COUNTER_DATA_TYPE_COUNT_MODE, \
+ .name = "count_mode", \
+ .count_u8_read = (_read), \
+ .count_u8_write = (_write), \
+ .priv = &(_available), \
+}
+
+#define COUNTER_DATA_DIRECTION(_read) \
+{ \
+ .type = COUNTER_DATA_TYPE_COUNT_DIRECTION, \
+ .name = "direction", \
+ .count_u8_read = (_read), \
+}
+
+#define COUNTER_DATA_ENABLE(_read, _write) \
+ COUNTER_DATA_COUNT_BOOL("enable", _read, _write)
+
+#define COUNTER_DATA_FLOOR(_read, _write) \
+ COUNTER_DATA_COUNT_U64("floor", _read, _write)
+
+#define COUNTER_DATA_PRESET(_read, _write) \
+ COUNTER_DATA_COUNT_U64("preset", _read, _write)
+
+#define COUNTER_DATA_PRESET_ENABLE(_read, _write) \
+ COUNTER_DATA_COUNT_BOOL("preset_enable", _read, _write)
+
#endif /* _COUNTER_H_ */
diff --git a/include/linux/counter_enum.h b/include/linux/counter_enum.h
deleted file mode 100644
index 9f917298a88f..000000000000
--- a/include/linux/counter_enum.h
+++ /dev/null
@@ -1,45 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0 */
-/*
- * Counter interface enum functions
- * Copyright (C) 2018 William Breathitt Gray
- */
-#ifndef _COUNTER_ENUM_H_
-#define _COUNTER_ENUM_H_
-
-#include <linux/types.h>
-
-struct counter_device;
-struct counter_signal;
-struct counter_count;
-
-ssize_t counter_signal_enum_read(struct counter_device *counter,
- struct counter_signal *signal, void *priv,
- char *buf);
-ssize_t counter_signal_enum_write(struct counter_device *counter,
- struct counter_signal *signal, void *priv,
- const char *buf, size_t len);
-
-ssize_t counter_signal_enum_available_read(struct counter_device *counter,
- struct counter_signal *signal,
- void *priv, char *buf);
-
-ssize_t counter_count_enum_read(struct counter_device *counter,
- struct counter_count *count, void *priv,
- char *buf);
-ssize_t counter_count_enum_write(struct counter_device *counter,
- struct counter_count *count, void *priv,
- const char *buf, size_t len);
-
-ssize_t counter_count_enum_available_read(struct counter_device *counter,
- struct counter_count *count,
- void *priv, char *buf);
-
-ssize_t counter_device_enum_read(struct counter_device *counter, void *priv,
- char *buf);
-ssize_t counter_device_enum_write(struct counter_device *counter, void *priv,
- const char *buf, size_t len);
-
-ssize_t counter_device_enum_available_read(struct counter_device *counter,
- void *priv, char *buf);
-
-#endif /* _COUNTER_ENUM_H_ */
diff --git a/include/uapi/linux/counter-types.h b/include/uapi/linux/counter-types.h
new file mode 100644
index 000000000000..78cdfefea25a
--- /dev/null
+++ b/include/uapi/linux/counter-types.h
@@ -0,0 +1,34 @@
+/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
+/*
+ * Counter interface data types
+ * Copyright (C) 2020 William Breathitt Gray
+ */
+#ifndef _UAPI_COUNTER_TYPES_H_
+#define _UAPI_COUNTER_TYPES_H_
+
+#define COUNTER_COUNT_DIRECTION_FORWARD 0
+#define COUNTER_COUNT_DIRECTION_BACKWARD 1
+
+#define COUNTER_COUNT_MODE_NORMAL 0
+#define COUNTER_COUNT_MODE_RANGE_LIMIT 1
+#define COUNTER_COUNT_MODE_NON_RECYCLE 2
+#define COUNTER_COUNT_MODE_MODULO_N 3
+
+#define COUNTER_COUNT_FUNCTION_INCREASE 0
+#define COUNTER_COUNT_FUNCTION_DECREASE 1
+#define COUNTER_COUNT_FUNCTION_PULSE_DIRECTION 2
+#define COUNTER_COUNT_FUNCTION_QUADRATURE_X1_A 3
+#define COUNTER_COUNT_FUNCTION_QUADRATURE_X1_B 4
+#define COUNTER_COUNT_FUNCTION_QUADRATURE_X2_A 5
+#define COUNTER_COUNT_FUNCTION_QUADRATURE_X2_B 6
+#define COUNTER_COUNT_FUNCTION_QUADRATURE_X4 7
+
+#define COUNTER_SIGNAL_LOW 0
+#define COUNTER_SIGNAL_HIGH 1
+
+#define COUNTER_SYNAPSE_ACTION_NONE 0
+#define COUNTER_SYNAPSE_ACTION_RISING_EDGE 1
+#define COUNTER_SYNAPSE_ACTION_FALLING_EDGE 2
+#define COUNTER_SYNAPSE_ACTION_BOTH_EDGES 3
+
+#endif /* _UAPI_COUNTER_TYPES_H_ */
--
2.26.2
^ permalink raw reply related [flat|nested] 10+ messages in thread
* [PATCH v3 2/4] docs: counter: Update to reflect sysfs internalization
2020-06-17 1:39 [PATCH v3 0/4] Introduce the Counter character device interface William Breathitt Gray
2020-06-17 1:39 ` [PATCH v3 1/4] counter: Internalize sysfs interface code William Breathitt Gray
@ 2020-06-17 1:40 ` William Breathitt Gray
2020-06-17 1:40 ` [PATCH v3 3/4] counter: Add character device interface William Breathitt Gray
2020-06-17 1:40 ` [PATCH v3 4/4] docs: counter: Document " William Breathitt Gray
3 siblings, 0 replies; 10+ messages in thread
From: William Breathitt Gray @ 2020-06-17 1:40 UTC (permalink / raw)
To: jic23
Cc: kamel.bouhara, gwendal, alexandre.belloni, david, linux-iio,
linux-kernel, linux-stm32, linux-arm-kernel, syednwaris,
patrick.havelange, fabrice.gasnier, mcoquelin.stm32,
alexandre.torgue, William Breathitt Gray
The Counter subsystem architecture and driver implementations have
changed in order to handle Counter sysfs interactions in a more
consistent way. This patch updates the Generic Counter interface
documentation to reflect the changes.
Signed-off-by: William Breathitt Gray <vilhelm.gray@gmail.com>
---
Documentation/driver-api/generic-counter.rst | 216 +++++++++++++------
1 file changed, 150 insertions(+), 66 deletions(-)
diff --git a/Documentation/driver-api/generic-counter.rst b/Documentation/driver-api/generic-counter.rst
index e622f8f6e56a..8aaa6cd37fd4 100644
--- a/Documentation/driver-api/generic-counter.rst
+++ b/Documentation/driver-api/generic-counter.rst
@@ -250,8 +250,8 @@ for defining a counter device.
.. kernel-doc:: drivers/counter/counter.c
:export:
-Implementation
-==============
+Driver Implementation
+=====================
To support a counter device, a driver must first allocate the available
Counter Signals via counter_signal structures. These Signals should
@@ -267,25 +267,59 @@ respective counter_count structure. These counter_count structures are
set to the counts array member of an allocated counter_device structure
before the Counter is registered to the system.
-Driver callbacks should be provided to the counter_device structure via
-a constant counter_ops structure in order to communicate with the
-device: to read and write various Signals and Counts, and to set and get
-the "action mode" and "function mode" for various Synapses and Counts
-respectively.
+Driver callbacks must be provided to the counter_device structure in
+order to communicate with the device: to read and write various Signals
+and Counts, and to set and get the "action mode" and "function mode" for
+various Synapses and Counts respectively.
A defined counter_device structure may be registered to the system by
passing it to the counter_register function, and unregistered by passing
it to the counter_unregister function. Similarly, the
-devm_counter_register and devm_counter_unregister functions may be used
-if device memory-managed registration is desired.
-
-Extension sysfs attributes can be created for auxiliary functionality
-and data by passing in defined counter_device_ext, counter_count_ext,
-and counter_signal_ext structures. In these cases, the
-counter_device_ext structure is used for global/miscellaneous exposure
-and configuration of the respective Counter device, while the
-counter_count_ext and counter_signal_ext structures allow for auxiliary
-exposure and configuration of a specific Count or Signal respectively.
+devm_counter_register function may be used if device memory-managed
+registration is desired.
+
+The struct counter_data structure is used to define counter extensions
+for Signals, Synapses, and Counts.
+
+The "type" member specifies the type of high-level data (e.g. BOOL,
+COUNT_DIRECTION, etc.) handled by this extension. The "`*_read`" and
+"`*_write`" members can then be set by the counter device driver with
+callbacks to handle that data using native C data types (i.e. u8, u64,
+etc.).
+
+Convenience macros such as `COUNTER_DATA_COUNT_U64` are provided for use
+by driver authors. In particular, driver authors are expected to use
+the provided macros for standard Counter subsystem attributes in order
+to maintain a consistent interface for userspace. For example, a counter
+device driver may define several standard attributes like so::
+
+ struct counter_data count_ext[] = {
+ COUNTER_DATA_DIRECTION(count_direction_read),
+ COUNTER_DATA_ENABLE(count_enable_read, count_enable_write),
+ COUNTER_DATA_CEILING(count_ceiling_read, count_ceiling_write),
+ };
+
+This makes it simple to see, add, and modify the attributes that are
+supported by this driver ("direction", "enable", and "ceiling") and to
+maintain this code without getting lost in a web of struct braces.
+
+Callbacks must match the function type expected for the respective
+component or extension. These function types are defined in the struct
+counter_data structure as the "`*_read`" and "`*_write`" union members.
+
+The corresponding callback prototypes for the extensions mentioned in
+the previous example above would be::
+
+ int count_direction_read(struct counter_device *counter,
+ struct counter_count *count, u8 *direction);
+ int count_enable_read(struct counter_device *counter,
+ struct counter_count *count, u8 *enable);
+ int count_enable_write(struct counter_device *counter,
+ struct counter_count *count, u8 enable);
+ int count_ceiling_read(struct counter_device *counter,
+ struct counter_count *count, u64 *ceiling);
+ int count_ceiling_write(struct counter_device *counter,
+ struct counter_count *count, u64 ceiling);
Determining the type of extension to create is a matter of scope.
@@ -313,52 +347,102 @@ Determining the type of extension to create is a matter of scope.
chip overheated via a device extension called "error_overtemp":
/sys/bus/counter/devices/counterX/error_overtemp
-Architecture
-============
-
-When the Generic Counter interface counter module is loaded, the
-counter_init function is called which registers a bus_type named
-"counter" to the system. Subsequently, when the module is unloaded, the
-counter_exit function is called which unregisters the bus_type named
-"counter" from the system.
-
-Counter devices are registered to the system via the counter_register
-function, and later removed via the counter_unregister function. The
-counter_register function establishes a unique ID for the Counter
-device and creates a respective sysfs directory, where X is the
-mentioned unique ID:
-
- /sys/bus/counter/devices/counterX
-
-Sysfs attributes are created within the counterX directory to expose
-functionality, configurations, and data relating to the Counts, Signals,
-and Synapses of the Counter device, as well as options and information
-for the Counter device itself.
-
-Each Signal has a directory created to house its relevant sysfs
-attributes, where Y is the unique ID of the respective Signal:
-
- /sys/bus/counter/devices/counterX/signalY
-
-Similarly, each Count has a directory created to house its relevant
-sysfs attributes, where Y is the unique ID of the respective Count:
-
- /sys/bus/counter/devices/counterX/countY
-
-For a more detailed breakdown of the available Generic Counter interface
-sysfs attributes, please refer to the
-Documentation/ABI/testing/sysfs-bus-counter file.
-
-The Signals and Counts associated with the Counter device are registered
-to the system as well by the counter_register function. The
-signal_read/signal_write driver callbacks are associated with their
-respective Signal attributes, while the count_read/count_write and
-function_get/function_set driver callbacks are associated with their
-respective Count attributes; similarly, the same is true for the
-action_get/action_set driver callbacks and their respective Synapse
-attributes. If a driver callback is left undefined, then the respective
-read/write permission is left disabled for the relevant attributes.
-
-Similarly, extension sysfs attributes are created for the defined
-counter_device_ext, counter_count_ext, and counter_signal_ext
-structures that are passed in.
+Subsystem Architecture
+======================
+
+Counter drivers pass and take data natively (i.e. `u8`, `u64`, etc.) and
+the shared counter module handles the translation between the sysfs
+interface. This gurantees a standard userspace interface for all counter
+drivers, and helps generalize the Generic Counter driver ABI in order to
+support the Generic Counter chrdev interface without significant changes
+to the existing counter drivers.
+
+A high-level view of how a count value is passed down from a counter
+driver is exemplified by the following::
+
+ Count data request:
+ ~~~~~~~~~~~~~~~~~~~
+ ----------------------
+ / Counter device \
+ +----------------------+
+ | Count register: 0x28 |
+ +----------------------+
+ |
+ -----------------
+ / raw count data /
+ -----------------
+ |
+ V
+ +----------------------------+
+ | Counter device driver |----------+
+ +----------------------------+ |
+ | Processes data from device | -------------------
+ |----------------------------| / driver callbacks /
+ | Type: unsigned long | -------------------
+ | Value: 42 | |
+ +----------------------------+ |
+ | |
+ ---------------- |
+ / unsigned long / |
+ ---------------- |
+ | |
+ | V
+ | +----------------------+
+ | | Counter core |
+ | +----------------------+
+ | | Routes device driver |
+ | | callbacks to the |
+ | | userspace interfaces |
+ | +----------------------+
+ | |
+ | -------------------
+ | / driver callbacks /
+ | -------------------
+ | |
+ +-------+ |
+ | |
+ | +---------------+
+ | |
+ V |
+ +--------------------+ |
+ | Counter sysfs |<-+
+ +--------------------+
+ | Translates to the |
+ | standard Counter |
+ | sysfs output |
+ |--------------------|
+ | Type: const char * |
+ | Value: "42" |
+ +--------------------+
+ |
+ ---------------
+ / const char * /
+ ---------------
+ |
+ V
+ +--------------------------------------------------+
+ | `/sys/bus/counter/devices/counterX/countY/count` |
+ +--------------------------------------------------+
+ \ Count: "42" /
+ --------------------------------------------------
+
+There are three primary components involved:
+
+Counter device driver
+---------------------
+Communicates with the hardware device to read/write data; e.g. counter
+drivers for quadrature encoders, timers, etc.
+
+Counter core
+------------
+Registers the counter device driver to the system so that the respective
+callbacks are called during userspace interaction.
+
+Counter sysfs
+-------------
+Translates counter data to the standard Counter sysfs interface format
+and vice versa.
+
+Please refer to the `Documentation/ABI/testing/sysfs-bus-counter` file
+for a detailed breakdown of the available Generic Counter interface
+sysfs attributes.
--
2.26.2
^ permalink raw reply related [flat|nested] 10+ messages in thread
* [PATCH v3 3/4] counter: Add character device interface
2020-06-17 1:39 [PATCH v3 0/4] Introduce the Counter character device interface William Breathitt Gray
2020-06-17 1:39 ` [PATCH v3 1/4] counter: Internalize sysfs interface code William Breathitt Gray
2020-06-17 1:40 ` [PATCH v3 2/4] docs: counter: Update to reflect sysfs internalization William Breathitt Gray
@ 2020-06-17 1:40 ` William Breathitt Gray
2020-06-20 18:50 ` David Lechner
2020-06-17 1:40 ` [PATCH v3 4/4] docs: counter: Document " William Breathitt Gray
3 siblings, 1 reply; 10+ messages in thread
From: William Breathitt Gray @ 2020-06-17 1:40 UTC (permalink / raw)
To: jic23
Cc: kamel.bouhara, gwendal, alexandre.belloni, david, linux-iio,
linux-kernel, linux-stm32, linux-arm-kernel, syednwaris,
patrick.havelange, fabrice.gasnier, mcoquelin.stm32,
alexandre.torgue, William Breathitt Gray
This patch introduces a character device interface for the Counter
subsystem. Device control is exposed through standard character device
read and write operations.
A /sys/bus/counter/devices/counterX/chrdev_format sysfs attribute is
introduced to expose the character device data format:
* Users may write to this sysfs attribute to select the components they
want to interface -- the layout can be determined as well from the
order. For example:
# echo "C0 C3 C2" > /sys/bus/counter/devices/counter0/chrdev_format
This would select Counts 0, 3, and 2 (in that order) to be available
in the /dev/counter0 node as a contiguous memory region.
You can select extensions in a similar fashion:
# echo "C4E2 S1E0" > /sys/bus/counter/devices/counter0/chrdev_format
This would select extension 2 from Count 4, and extension 0 from
Signal 1.
* Users may read from this chrdev_format sysfs attribute in order to see
the currently configured format of the character device.
* Users may perform read/write operations on the /dev/counterX node
directly; the layout of the data is what they user has configured via
the chrdev_format sysfs attribute. For example:
# echo "C0 C1 S0 S1" > /sys/bus/counter/devices/counter0/chrdev_format
Yields the following /dev/counter0 memory layout:
+-----------------+------------------+----------+----------+
| Byte 0 - Byte 7 | Byte 8 - Byte 15 | Byte 16 | Byte 17 |
+-----------------+------------------+----------+----------+
| Count 0 | Count 1 | Signal 0 | Signal 2 |
+-----------------+------------------+----------+----------+
The number of bytes allotted for each component or extension is
determined by its respective data type: u8 will have 1 byte allotted,
u64 will have 8 bytes allotted, etc.
A high-level view of how a count value is passed down from a counter
driver is exemplified by the following:
----------------------
/ Counter device \
+----------------------+
| Count register: 0x28 |
+----------------------+
|
-----------------
/ raw count data /
-----------------
|
V
+----------------------------+
| Counter device driver |----------+
+----------------------------+ |
| Processes data from device | -------------------
|----------------------------| / driver callbacks /
| Type: u64 | -------------------
| Value: 42 | |
+----------------------------+ |
| |
---------- |
/ u64 / |
---------- |
| |
| V
| +----------------------+
| | Counter core |
| +----------------------+
| | Routes device driver |
| | callbacks to the |
| | userspace interfaces |
| +----------------------+
| |
| -------------------
| / driver callbacks /
| -------------------
| |
+-------+---------------+ |
| | |
| +-------|-------+
| | |
V | V
+--------------------+ | +---------------------+
| Counter sysfs |<-+->| Counter chrdev |
+--------------------+ +---------------------+
| Translates to the | | Translates to the |
| standard Counter | | standard Counter |
| sysfs output | | character device |
|--------------------| |---------------------+
| Type: const char * | | Type: u64 |
| Value: "42" | | Value: 42 |
+--------------------+ +---------------------+
| |
--------------- ----------
/ const char * / / u64 /
--------------- ----------
| |
| V
| +-----------+
| | read |
| +-----------+
| \ Count: 42 /
| -----------
|
V
+--------------------------------------------------+
| `/sys/bus/counter/devices/counterX/countY/count` |
+--------------------------------------------------+
\ Count: "42" /
--------------------------------------------------
Signed-off-by: William Breathitt Gray <vilhelm.gray@gmail.com>
---
MAINTAINERS | 1 +
drivers/counter/Makefile | 2 +-
drivers/counter/counter-chrdev.c | 612 +++++++++++++++++++++++++++++++
drivers/counter/counter-chrdev.h | 23 ++
drivers/counter/counter-core.c | 34 +-
drivers/counter/counter-sysfs.c | 38 +-
include/linux/counter.h | 12 +-
7 files changed, 714 insertions(+), 8 deletions(-)
create mode 100644 drivers/counter/counter-chrdev.c
create mode 100644 drivers/counter/counter-chrdev.h
diff --git a/MAINTAINERS b/MAINTAINERS
index 7ea12db794be..b4ed407a13f8 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -4413,6 +4413,7 @@ F: Documentation/ABI/testing/sysfs-bus-counter*
F: Documentation/driver-api/generic-counter.rst
F: drivers/counter/
F: include/linux/counter.h
+F: include/uapi/linux/counter.h
F: include/uapi/linux/counter-types.h
CPMAC ETHERNET DRIVER
diff --git a/drivers/counter/Makefile b/drivers/counter/Makefile
index f48e337cbd85..d219b9c058e7 100644
--- a/drivers/counter/Makefile
+++ b/drivers/counter/Makefile
@@ -4,7 +4,7 @@
#
obj-$(CONFIG_COUNTER) += counter.o
-counter-y := counter-core.o counter-sysfs.o
+counter-y := counter-core.o counter-sysfs.o counter-chrdev.o
obj-$(CONFIG_104_QUAD_8) += 104-quad-8.o
obj-$(CONFIG_STM32_TIMER_CNT) += stm32-timer-cnt.o
diff --git a/drivers/counter/counter-chrdev.c b/drivers/counter/counter-chrdev.c
new file mode 100644
index 000000000000..e143380edd21
--- /dev/null
+++ b/drivers/counter/counter-chrdev.c
@@ -0,0 +1,612 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Generic Counter character device interface
+ * Copyright (C) 2020 William Breathitt Gray
+ */
+
+#include <linux/cdev.h>
+#include <linux/counter.h>
+#include <linux/ctype.h>
+#include <linux/device.h>
+#include <linux/err.h>
+#include <linux/fs.h>
+#include <linux/kdev_t.h>
+#include <linux/kernel.h>
+#include <linux/list.h>
+#include <linux/mutex.h>
+#include <linux/slab.h>
+#include <linux/string.h>
+#include <linux/types.h>
+#include <linux/uaccess.h>
+
+#include "counter-chrdev.h"
+#include "counter-common.h"
+
+struct counter_control {
+ loff_t offset;
+ size_t size;
+ struct list_head l;
+
+ struct counter_data data;
+ enum counter_owner_type type;
+ void *owner;
+};
+
+static int counter_data_u8_read(struct counter_device *const counter,
+ const struct counter_control *const control,
+ u8 __user *const buf)
+{
+ const struct counter_data *const data = &control->data;
+ int err;
+ u8 val;
+
+ switch (control->type) {
+ case COUNTER_OWNER_TYPE_DEVICE:
+ err = data->device_u8_read(counter, &val);
+ break;
+ case COUNTER_OWNER_TYPE_SIGNAL:
+ err = data->signal_u8_read(counter, control->owner, &val);
+ break;
+ case COUNTER_OWNER_TYPE_COUNT:
+ if (data->type == COUNTER_DATA_TYPE_SYNAPSE_ACTION)
+ err = data->action_read(counter, control->owner,
+ data->priv, &val);
+ else
+ err = data->count_u8_read(counter, control->owner,
+ &val);
+ break;
+ }
+ if (err)
+ return err;
+
+ return put_user(val, buf);
+}
+
+static int counter_data_u64_read(struct counter_device *const counter,
+ const struct counter_control *const control,
+ char __user *const buf, const size_t len,
+ const size_t offset)
+{
+ const struct counter_data *const data = &control->data;
+ int err;
+ u64 val;
+
+ switch (control->type) {
+ case COUNTER_OWNER_TYPE_DEVICE:
+ err = data->device_u64_read(counter, &val);
+ break;
+ case COUNTER_OWNER_TYPE_SIGNAL:
+ err = data->signal_u64_read(counter, control->owner, &val);
+ break;
+ case COUNTER_OWNER_TYPE_COUNT:
+ err = data->count_u64_read(counter, control->owner, &val);
+ break;
+ }
+ if (err)
+ return err;
+
+ return copy_to_user(buf, (const char *)&val + offset, len);
+}
+
+static int counter_control_read(struct counter_device *const counter,
+ const struct counter_control *const control,
+ char __user *const buf, const size_t len,
+ const size_t offset)
+{
+ /* Check if read operation is supported */
+ if (!control->data.device_u8_read)
+ return -EFAULT;
+
+ switch (control->data.type) {
+ case COUNTER_DATA_TYPE_U8:
+ case COUNTER_DATA_TYPE_BOOL:
+ case COUNTER_DATA_TYPE_SIGNAL:
+ case COUNTER_DATA_TYPE_COUNT_FUNCTION:
+ case COUNTER_DATA_TYPE_SYNAPSE_ACTION:
+ case COUNTER_DATA_TYPE_ENUM:
+ case COUNTER_DATA_TYPE_COUNT_DIRECTION:
+ case COUNTER_DATA_TYPE_COUNT_MODE:
+ return counter_data_u8_read(counter, control, buf);
+ case COUNTER_DATA_TYPE_U64:
+ return counter_data_u64_read(counter, control, buf, len,
+ offset);
+ }
+
+ return -EINVAL;
+}
+
+static ssize_t counter_chrdev_read(struct file *filp, char __user *buf,
+ size_t len, loff_t *f_ps)
+{
+ struct counter_device *const counter = filp->private_data;
+ const loff_t start_ps = *f_ps;
+ struct counter_control *control;
+ loff_t next_control_ps;
+ size_t read_size;
+ int err;
+
+ mutex_lock(&counter->control_lock);
+
+ /* Handle controls */
+ list_for_each_entry(control, &counter->control_list, l) {
+ next_control_ps = control->offset + control->size;
+
+ /* Find first control item */
+ if (*f_ps >= next_control_ps)
+ continue;
+
+ read_size = (*f_ps + len > next_control_ps) ?
+ next_control_ps - *f_ps : len;
+
+ err = counter_control_read(counter, control, buf, read_size,
+ control->offset - *f_ps);
+ if (err) {
+ mutex_unlock(&counter->control_lock);
+ return err;
+ }
+
+ *f_ps += read_size;
+ buf += read_size;
+ len -= read_size;
+ if (!len)
+ goto exit_chrdev_read;
+ }
+
+exit_chrdev_read:
+ mutex_unlock(&counter->control_lock);
+ return *f_ps - start_ps;
+}
+
+static int counter_data_u8_write(struct counter_device *const counter,
+ const struct counter_control *const control,
+ const u8 __user *const buf)
+{
+ const struct counter_data *const data = &control->data;
+ int err;
+ u8 val;
+
+ err = get_user(val, buf);
+ if (err)
+ return err;
+
+ switch (control->type) {
+ case COUNTER_OWNER_TYPE_DEVICE:
+ err = data->device_u8_write(counter, val);
+ break;
+ case COUNTER_OWNER_TYPE_SIGNAL:
+ err = data->signal_u8_write(counter, control->owner, val);
+ break;
+ case COUNTER_OWNER_TYPE_COUNT:
+ if (data->type == COUNTER_DATA_TYPE_SYNAPSE_ACTION)
+ err = data->action_write(counter, control->owner,
+ data->priv, val);
+ else
+ err = data->count_u8_write(counter, control->owner,
+ val);
+ break;
+ }
+
+ return err;
+}
+
+static int counter_data_u64_write(struct counter_device *const counter,
+ const struct counter_control *const control,
+ const char __user *const buf,
+ const size_t len, const size_t offset)
+{
+ const struct counter_data *const data = &control->data;
+ int err;
+ u64 val = 0;
+
+ err = copy_from_user((char *)&val + offset, buf, len);
+ if (err)
+ return err;
+
+ switch (control->type) {
+ case COUNTER_OWNER_TYPE_DEVICE:
+ err = data->device_u64_write(counter, val);
+ break;
+ case COUNTER_OWNER_TYPE_SIGNAL:
+ err = data->signal_u64_write(counter, control->owner, val);
+ break;
+ case COUNTER_OWNER_TYPE_COUNT:
+ err = data->count_u64_write(counter, control->owner, val);
+ break;
+ }
+
+ return err;
+}
+
+static int counter_control_write(struct counter_device *const counter,
+ const struct counter_control *const control,
+ const char __user *const buf, const size_t len,
+ const size_t offset)
+{
+ /* Check if write operation is supported */
+ if (!control->data.device_u8_write)
+ return -EFAULT;
+
+ switch (control->data.type) {
+ case COUNTER_DATA_TYPE_U8:
+ case COUNTER_DATA_TYPE_BOOL:
+ case COUNTER_DATA_TYPE_SIGNAL:
+ case COUNTER_DATA_TYPE_COUNT_FUNCTION:
+ case COUNTER_DATA_TYPE_SYNAPSE_ACTION:
+ case COUNTER_DATA_TYPE_ENUM:
+ case COUNTER_DATA_TYPE_COUNT_DIRECTION:
+ case COUNTER_DATA_TYPE_COUNT_MODE:
+ return counter_data_u8_write(counter, control, buf);
+ case COUNTER_DATA_TYPE_U64:
+ return counter_data_u64_write(counter, control, buf, len,
+ offset);
+ }
+
+ return -EINVAL;
+}
+
+static ssize_t counter_chrdev_write(struct file *filp, const char __user *buf,
+ size_t len, loff_t *f_ps)
+{
+ struct counter_device *const counter = filp->private_data;
+ const loff_t start_ps = *f_ps;
+ struct counter_control *control;
+ loff_t next_control_ps;
+ size_t write_size;
+ int err;
+
+ mutex_lock(&counter->control_lock);
+
+ /* Handle controls */
+ list_for_each_entry(control, &counter->control_list, l) {
+ next_control_ps = control->offset + control->size;
+
+ /* Find first control item */
+ if (*f_ps >= next_control_ps)
+ continue;
+
+ write_size = (*f_ps + len > next_control_ps) ?
+ next_control_ps - *f_ps : len;
+
+ err = counter_control_write(counter, control, buf, write_size,
+ control->offset - *f_ps);
+ if (err) {
+ mutex_unlock(&counter->control_lock);
+ return err;
+ }
+
+ *f_ps += write_size;
+ buf += write_size;
+ len -= write_size;
+ if (!len)
+ goto exit_chrdev_write;
+ }
+
+ mutex_unlock(&counter->control_lock);
+
+ return -EFAULT;
+
+exit_chrdev_write:
+ mutex_unlock(&counter->control_lock);
+ return *f_ps - start_ps;
+}
+
+static int counter_chrdev_open(struct inode *inode, struct file *filp)
+{
+ struct counter_device *const counter = container_of(inode->i_cdev,
+ typeof(*counter),
+ chrdev);
+
+ get_device(&counter->dev);
+ filp->private_data = counter;
+
+ return generic_file_open(inode, filp);
+}
+
+static int counter_chrdev_release(struct inode *inode, struct file *filp)
+{
+ struct counter_device *const counter = container_of(inode->i_cdev,
+ typeof(*counter),
+ chrdev);
+
+ put_device(&counter->dev);
+
+ return 0;
+}
+
+static const struct file_operations counter_fops = {
+ .llseek = generic_file_llseek,
+ .read = counter_chrdev_read,
+ .write = counter_chrdev_write,
+ .open = counter_chrdev_open,
+ .release = counter_chrdev_release,
+};
+
+int counter_chrdev_add(struct counter_device *const counter,
+ const dev_t counter_devt)
+{
+ struct device *const dev = &counter->dev;
+ struct cdev *const chrdev = &counter->chrdev;
+
+ /* Initialize Counter character device selected controls list */
+ INIT_LIST_HEAD(&counter->control_list);
+
+ /* Initialize mutex for Counter character device selected controls */
+ mutex_init(&counter->control_lock);
+
+ /* Initialize character device */
+ cdev_init(chrdev, &counter_fops);
+ dev->devt = MKDEV(MAJOR(counter_devt), counter->id);
+ cdev_set_parent(chrdev, &dev->kobj);
+
+ return cdev_add(chrdev, dev->devt, 1);
+}
+
+static void counter_control_list_free(struct list_head *const controls)
+{
+ struct counter_control *p, *n;
+
+ list_for_each_entry_safe(p, n, controls, l) {
+ list_del(&p->l);
+ kfree(p);
+ }
+}
+
+void counter_chrdev_free(struct counter_device *const counter)
+{
+ cdev_del(&counter->chrdev);
+
+ mutex_lock(&counter->control_lock);
+ counter_control_list_free(&counter->control_list);
+ mutex_unlock(&counter->control_lock);
+}
+
+ssize_t counter_chrdev_format_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct counter_device *const counter = dev_get_drvdata(dev);
+ const struct counter_signal *signal = counter->signals;
+ const struct counter_count *count = counter->counts;
+ size_t len = 0;
+ struct counter_control *control;
+ struct counter_data *ext;
+ size_t idx;
+ const struct counter_synapse *synapse;
+
+ mutex_lock(&counter->control_lock);
+
+ list_for_each_entry(control, &counter->control_list, l) {
+ switch (control->type) {
+ case COUNTER_OWNER_TYPE_DEVICE:
+ ext = counter->ext;
+ idx = counter->num_ext;
+ break;
+ case COUNTER_OWNER_TYPE_SIGNAL:
+ signal = control->owner;
+ ext = signal->ext;
+ idx = signal->num_ext;
+ len += sprintf(buf + len, "S%zu",
+ signal - counter->signals);
+ break;
+ case COUNTER_OWNER_TYPE_COUNT:
+ count = control->owner;
+ ext = count->ext;
+ idx = count->num_ext;
+ len += sprintf(buf + len, "C%zu",
+ count - counter->counts);
+ break;
+ }
+
+ switch (control->data.type) {
+ default:
+ /* Handle "count" control item */
+ if (control->data.count_u64_read == counter->count_read)
+ break;
+
+ /* Determine extension index */
+ while (--idx)
+ if (!strcmp(ext[idx].name, control->data.name))
+ break;
+
+ len += sprintf(buf + len, "E%zu", idx);
+ break;
+ case COUNTER_DATA_TYPE_COUNT_FUNCTION:
+ buf[len++] = 'F';
+ break;
+ case COUNTER_DATA_TYPE_SYNAPSE_ACTION:
+ synapse = control->data.priv;
+ len += sprintf(buf + len, "A%zu",
+ synapse - count->synapses);
+ break;
+ case COUNTER_DATA_TYPE_SIGNAL:
+ break;
+ }
+
+ buf[len++] = ' ';
+ }
+
+ mutex_unlock(&counter->control_lock);
+
+ return len;
+}
+
+static int counter_control_add(struct list_head *const controls,
+ const struct counter_data *const data,
+ const enum counter_owner_type type,
+ void *const owner)
+{
+ const struct counter_control *const tail = list_last_entry(controls,
+ typeof(*tail),
+ l);
+ struct counter_control *control;
+
+ /* Generate control list item */
+ control = kzalloc(sizeof(*control), GFP_KERNEL);
+ if (!control)
+ return -ENOMEM;
+
+ /* Configure control list item */
+ control->data = *data;
+ control->type = type;
+ control->owner = owner;
+ control->offset = list_empty(controls) ? 0 : tail->offset + tail->size;
+ switch (control->data.type) {
+ case COUNTER_DATA_TYPE_U8:
+ case COUNTER_DATA_TYPE_BOOL:
+ case COUNTER_DATA_TYPE_SIGNAL:
+ case COUNTER_DATA_TYPE_COUNT_FUNCTION:
+ case COUNTER_DATA_TYPE_SYNAPSE_ACTION:
+ case COUNTER_DATA_TYPE_ENUM:
+ case COUNTER_DATA_TYPE_COUNT_DIRECTION:
+ case COUNTER_DATA_TYPE_COUNT_MODE:
+ control->size = sizeof(u8);
+ break;
+ case COUNTER_DATA_TYPE_U64:
+ control->size = sizeof(u64);
+ break;
+ }
+
+ /* Add control list item to the list */
+ list_add_tail(&control->l, controls);
+
+ return 0;
+}
+
+ssize_t counter_chrdev_format_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t len)
+{
+ struct counter_device *const counter = dev_get_drvdata(dev);
+ struct list_head *const controls = &counter->control_list;
+ size_t pos = skip_spaces(buf) - buf;
+ int num;
+ char id, subid;
+ size_t idx, subidx, maxidx;
+ struct counter_signal *signal;
+ struct counter_count *count;
+ struct counter_data *ext;
+ struct counter_data data;
+ enum counter_owner_type type;
+ void *owner;
+ int err;
+
+ mutex_lock(&counter->control_lock);
+
+ /* Clean up old list */
+ counter_control_list_free(controls);
+
+ while (pos < len) {
+ /* Scan item */
+ num = sscanf(buf + pos, "%c%zu%c%zu", &id, &idx, &subid,
+ &subidx);
+ if (num < 2) {
+ err = -EINVAL;
+ goto err_control_create;
+ }
+
+ /* Ignore trailing whitespace */
+ if (isspace(subid))
+ num = 2;
+
+ /* Process owner */
+ switch (id) {
+ case 'S':
+ if (idx > counter->num_signals - 1) {
+ err = -EINVAL;
+ goto err_control_create;
+ }
+ signal = counter->signals + idx;
+ ext = signal->ext;
+ maxidx = signal->num_ext - 1;
+
+ /* Handle Signal item */
+ data.type = COUNTER_DATA_TYPE_SIGNAL;
+ data.signal_u8_read = counter->signal_read;
+ type = COUNTER_OWNER_TYPE_SIGNAL;
+ owner = signal;
+ break;
+ case 'C':
+ if (idx > counter->num_counts - 1) {
+ err = -EINVAL;
+ goto err_control_create;
+ }
+ count = counter->counts + idx;
+ ext = count->ext;
+ maxidx = count->num_ext - 1;
+
+ /* Handle Count item */
+ data.type = COUNTER_DATA_TYPE_U64,
+ data.count_u64_read = counter->count_read;
+ data.count_u64_write = counter->count_write;
+ type = COUNTER_OWNER_TYPE_COUNT;
+ owner = count;
+ break;
+ case 'E':
+ if (num > 2 || idx > counter->num_ext - 1) {
+ err = -EINVAL;
+ goto err_control_create;
+ }
+
+ /* Handle device extension item */
+ data = counter->ext[idx];
+ type = COUNTER_OWNER_TYPE_DEVICE;
+ owner = NULL;
+ break;
+ default:
+ err = -EINVAL;
+ goto err_control_create;
+ }
+
+ if (num == 3) {
+ if (subid != 'F') {
+ err = -EINVAL;
+ goto err_control_create;
+ }
+
+ /* Handle count function item */
+ data.type = COUNTER_DATA_TYPE_COUNT_FUNCTION,
+ data.count_u8_read = counter->function_read;
+ data.count_u8_write = counter->function_write;
+ } else if (num == 4) {
+ if (subidx > maxidx) {
+ err = -EINVAL;
+ goto err_control_create;
+ }
+
+ switch (subid) {
+ case 'A':
+ /* Handle Synapse action item */
+ data.type = COUNTER_DATA_TYPE_SYNAPSE_ACTION;
+ data.action_read = counter->action_read;
+ data.action_write = counter->action_write;
+ data.priv = count->synapses + subidx;
+ break;
+ case 'E':
+ /* Handle component extension item */
+ data = ext[subidx];
+ break;
+ default:
+ err = -EINVAL;
+ goto err_control_create;
+ }
+ }
+
+ /* Generate control item */
+ err = counter_control_add(controls, &data, type, owner);
+ if (err)
+ goto err_control_create;
+
+ /* Jump to next item */
+ while (isalnum(buf[pos]))
+ pos++;
+ pos = skip_spaces(buf + pos) - buf;
+ }
+
+ mutex_unlock(&counter->control_lock);
+
+ return len;
+
+err_control_create:
+ counter_control_list_free(controls);
+ mutex_unlock(&counter->control_lock);
+ return err;
+}
diff --git a/drivers/counter/counter-chrdev.h b/drivers/counter/counter-chrdev.h
new file mode 100644
index 000000000000..73af6d236bc8
--- /dev/null
+++ b/drivers/counter/counter-chrdev.h
@@ -0,0 +1,23 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Counter character device interface
+ * Copyright (C) 2020 William Breathitt Gray
+ */
+#ifndef _COUNTER_CHRDEV_H_
+#define _COUNTER_CHRDEV_H_
+
+#include <linux/counter.h>
+#include <linux/device.h>
+#include <linux/types.h>
+
+int counter_chrdev_add(struct counter_device *const counter,
+ const dev_t counter_devt);
+void counter_chrdev_free(struct counter_device *const counter);
+
+ssize_t counter_chrdev_format_show(struct device *dev,
+ struct device_attribute *attr, char *buf);
+ssize_t counter_chrdev_format_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t len);
+
+#endif /* _COUNTER_CHRDEV_H_ */
diff --git a/drivers/counter/counter-core.c b/drivers/counter/counter-core.c
index 499664809c75..2d0886648201 100644
--- a/drivers/counter/counter-core.c
+++ b/drivers/counter/counter-core.c
@@ -6,11 +6,14 @@
#include <linux/counter.h>
#include <linux/device.h>
#include <linux/export.h>
+#include <linux/fs.h>
#include <linux/gfp.h>
#include <linux/idr.h>
#include <linux/init.h>
#include <linux/module.h>
+#include <linux/types.h>
+#include "counter-chrdev.h"
#include "counter-sysfs.h"
/* Provides a unique ID for each counter device */
@@ -33,6 +36,8 @@ static struct bus_type counter_bus_type = {
.name = "counter"
};
+static dev_t counter_devt;
+
/**
* counter_register - register Counter to the system
* @counter: pointer to Counter to register
@@ -62,10 +67,15 @@ int counter_register(struct counter_device *const counter)
device_initialize(dev);
dev_set_drvdata(dev, counter);
+ /* Add Counter character device */
+ err = counter_chrdev_add(counter, counter_devt);
+ if (err)
+ goto err_free_id;
+
/* Add Counter sysfs attributes */
err = counter_sysfs_add(counter);
if (err)
- goto err_free_id;
+ goto err_free_chrdev;
/* Add device to system */
err = device_add(dev);
@@ -76,6 +86,8 @@ int counter_register(struct counter_device *const counter)
err_free_sysfs:
counter_sysfs_free(counter);
+err_free_chrdev:
+ counter_chrdev_free(counter);
err_free_id:
ida_simple_remove(&counter_ida, counter->id);
return err;
@@ -93,6 +105,7 @@ void counter_unregister(struct counter_device *const counter)
if (counter) {
device_del(&counter->dev);
counter_sysfs_free(counter);
+ counter_chrdev_free(counter);
}
}
EXPORT_SYMBOL_GPL(counter_unregister);
@@ -139,13 +152,30 @@ int devm_counter_register(struct device *dev,
}
EXPORT_SYMBOL_GPL(devm_counter_register);
+#define COUNTER_DEV_MAX 256
+
static int __init counter_init(void)
{
- return bus_register(&counter_bus_type);
+ int err;
+
+ err = bus_register(&counter_bus_type);
+ if (err < 0)
+ return err;
+
+ err = alloc_chrdev_region(&counter_devt, 0, COUNTER_DEV_MAX, "counter");
+ if (err < 0)
+ goto err_unregister_bus;
+
+ return 0;
+
+err_unregister_bus:
+ bus_unregister(&counter_bus_type);
+ return err;
}
static void __exit counter_exit(void)
{
+ unregister_chrdev_region(counter_devt, COUNTER_DEV_MAX);
bus_unregister(&counter_bus_type);
}
diff --git a/drivers/counter/counter-sysfs.c b/drivers/counter/counter-sysfs.c
index ca69e9d4e833..1279bd8a8af1 100644
--- a/drivers/counter/counter-sysfs.c
+++ b/drivers/counter/counter-sysfs.c
@@ -15,6 +15,7 @@
#include <linux/types.h>
#include "counter-common.h"
+#include "counter-chrdev.h"
#include "counter-sysfs.h"
struct counter_attribute {
@@ -658,11 +659,29 @@ static int counter_num_counts_read(struct counter_device *counter, u8 *val)
return 0;
}
-static struct counter_data counter_num_signals_data =
- COUNTER_DATA_DEVICE_U8("num_signals", counter_num_signals_read, NULL);
+static int counter_format_attr_create(struct counter_attribute_group *group,
+ struct counter_device *const counter)
+{
+ struct counter_attribute *counter_attr;
+ struct device_attribute *dev_attr;
-static struct counter_data counter_num_counts_data =
- COUNTER_DATA_DEVICE_U8("num_counts", counter_num_counts_read, NULL);
+ /* Allocate Counter attribute */
+ counter_attr = kzalloc(sizeof(*counter_attr), GFP_KERNEL);
+ if (!counter_attr)
+ return -ENOMEM;
+ list_add(&counter_attr->l, &group->attr_list);
+ group->num_attr++;
+
+ /* Configure device attribute */
+ dev_attr = &counter_attr->dev_attr;
+ sysfs_attr_init(&dev_attr->attr);
+ dev_attr->attr.name = "chrdev_format";
+ dev_attr->attr.mode = 0644;
+ dev_attr->show = counter_chrdev_format_show;
+ dev_attr->store = counter_chrdev_format_store;
+
+ return 0;
+}
static void counter_groups_list_free(struct counter_device *const counter)
{
@@ -685,6 +704,12 @@ static void counter_groups_list_free(struct counter_device *const counter)
kfree(counter->groups_list);
}
+static struct counter_data counter_num_signals_data =
+ COUNTER_DATA_DEVICE_U8("num_signals", counter_num_signals_read, NULL);
+
+static struct counter_data counter_num_counts_data =
+ COUNTER_DATA_DEVICE_U8("num_counts", counter_num_counts_read, NULL);
+
static int counter_device_register(struct counter_attribute_group *group,
struct counter_device *const counter)
{
@@ -732,6 +757,11 @@ static int counter_device_register(struct counter_attribute_group *group,
goto err_free_groups_list;
}
+ /* Create chrdev_format attribute */
+ err = counter_format_attr_create(group, counter);
+ if (err)
+ goto err_free_groups_list;
+
return 0;
err_free_groups_list:
diff --git a/include/linux/counter.h b/include/linux/counter.h
index 3eb567a5884b..88cc4f32dc2d 100644
--- a/include/linux/counter.h
+++ b/include/linux/counter.h
@@ -6,9 +6,11 @@
#ifndef _COUNTER_H_
#define _COUNTER_H_
+#include <linux/cdev.h>
#include <linux/device.h>
#include <linux/kernel.h>
#include <linux/list.h>
+#include <linux/mutex.h>
#include <linux/types.h>
#include <uapi/linux/counter-types.h>
@@ -21,8 +23,8 @@ enum counter_data_type {
COUNTER_DATA_TYPE_U8,
COUNTER_DATA_TYPE_U64,
COUNTER_DATA_TYPE_BOOL,
- COUNTER_DATA_TYPE_COUNT_FUNCTION,
COUNTER_DATA_TYPE_SIGNAL,
+ COUNTER_DATA_TYPE_COUNT_FUNCTION,
COUNTER_DATA_TYPE_SYNAPSE_ACTION,
COUNTER_DATA_TYPE_ENUM,
COUNTER_DATA_TYPE_COUNT_DIRECTION,
@@ -166,6 +168,9 @@ struct counter_attribute_group {
* @priv: optional private data supplied by driver
* @id: unique ID used to identify the Counter
* @dev: internal device structure
+ * @chrdev: internal character device structure
+ * @control_list: Counter character device selected controls
+ * @control_lock: Mutex for Counter character device selected controls
* @dynamic_names_list: List for dynamic names
* @groups_list: attribute groups list (for Signals, Counts, and ext)
* @num_groups: number of attribute groups containers
@@ -204,6 +209,11 @@ struct counter_device {
int id;
struct device dev;
+ struct cdev chrdev;
+
+ struct list_head control_list;
+ struct mutex control_lock;
+
struct list_head dynamic_names_list;
struct counter_attribute_group *groups_list;
size_t num_groups;
--
2.26.2
^ permalink raw reply related [flat|nested] 10+ messages in thread
* [PATCH v3 4/4] docs: counter: Document character device interface
2020-06-17 1:39 [PATCH v3 0/4] Introduce the Counter character device interface William Breathitt Gray
` (2 preceding siblings ...)
2020-06-17 1:40 ` [PATCH v3 3/4] counter: Add character device interface William Breathitt Gray
@ 2020-06-17 1:40 ` William Breathitt Gray
3 siblings, 0 replies; 10+ messages in thread
From: William Breathitt Gray @ 2020-06-17 1:40 UTC (permalink / raw)
To: jic23
Cc: kamel.bouhara, gwendal, alexandre.belloni, david, linux-iio,
linux-kernel, linux-stm32, linux-arm-kernel, syednwaris,
patrick.havelange, fabrice.gasnier, mcoquelin.stm32,
alexandre.torgue, William Breathitt Gray
This patch adds high-level documentation about the Counter subsystem
character device interface.
Signed-off-by: William Breathitt Gray <vilhelm.gray@gmail.com>
---
Documentation/ABI/testing/sysfs-bus-counter | 31 +++++
Documentation/driver-api/generic-counter.rst | 132 ++++++++++++++-----
2 files changed, 127 insertions(+), 36 deletions(-)
diff --git a/Documentation/ABI/testing/sysfs-bus-counter b/Documentation/ABI/testing/sysfs-bus-counter
index 566bd99fe0a5..8533a8732544 100644
--- a/Documentation/ABI/testing/sysfs-bus-counter
+++ b/Documentation/ABI/testing/sysfs-bus-counter
@@ -193,6 +193,37 @@ Description:
both edges:
Any state transition.
+What: /sys/bus/counter/devices/counterX/chrdev_format
+KernelVersion: 5.9
+Contact: linux-iio@vger.kernel.org
+Description:
+ Data format of the respective character device node of the
+ Counter. Reading this attribute returns the current data format
+ of the respective character device node; writing to this
+ attribute sets the current data format of the respective
+ character device node. This attribute interfaces via the
+ following format:
+
+ Components/extensions are specified by a character identifier
+ and an index offset; whitespace serves as delimiters. The
+ following character identifiers are supported:
+
+ C: Count
+ S: Signal
+ E: Extension
+ A: Synapse Action
+ F: Count Function
+
+ Count/Signal extensions may be specified by first specifying the
+ respective owning component then the desired extension
+ immediately following without delimiting whitespace; Synapse
+ Action and Count Function are specified in a similar manner.
+
+ For example, "C4 C2E6 C0F S7E1 C3A4 S5" would specify the
+ following data format: Count 4, Count 2's Extension 6, Count 0's
+ Count Function, Signal 7's Extension 1, Count 3's Synapse Action
+ 4, Signal 5.
+
What: /sys/bus/counter/devices/counterX/name
KernelVersion: 5.2
Contact: linux-iio@vger.kernel.org
diff --git a/Documentation/driver-api/generic-counter.rst b/Documentation/driver-api/generic-counter.rst
index 8aaa6cd37fd4..d46ce65d1488 100644
--- a/Documentation/driver-api/generic-counter.rst
+++ b/Documentation/driver-api/generic-counter.rst
@@ -223,19 +223,6 @@ whether an input line is differential or single-ended) and instead focus
on the core idea of what the data and process represent (e.g. position
as interpreted from quadrature encoding data).
-Userspace Interface
-===================
-
-Several sysfs attributes are generated by the Generic Counter interface,
-and reside under the /sys/bus/counter/devices/counterX directory, where
-counterX refers to the respective counter device. Please see
-Documentation/ABI/testing/sysfs-bus-counter for detailed
-information on each Generic Counter interface sysfs attribute.
-
-Through these sysfs attributes, programs and scripts may interact with
-the Generic Counter paradigm Counts, Signals, and Synapses of respective
-counter devices.
-
Driver API
==========
@@ -378,13 +365,13 @@ driver is exemplified by the following::
+----------------------------+ |
| Processes data from device | -------------------
|----------------------------| / driver callbacks /
- | Type: unsigned long | -------------------
+ | Type: u64 | -------------------
| Value: 42 | |
+----------------------------+ |
| |
- ---------------- |
- / unsigned long / |
- ---------------- |
+ ---------- |
+ / u64 / |
+ ---------- |
| |
| V
| +----------------------+
@@ -399,25 +386,32 @@ driver is exemplified by the following::
| / driver callbacks /
| -------------------
| |
- +-------+ |
+ +-------+---------------+ |
+ | | |
+ | +-------|-------+
+ | | |
+ V | V
+ +--------------------+ | +---------------------+
+ | Counter sysfs |<-+->| Counter chrdev |
+ +--------------------+ +---------------------+
+ | Translates to the | | Translates to the |
+ | standard Counter | | standard Counter |
+ | sysfs output | | character device |
+ |--------------------| |---------------------+
+ | Type: const char * | | Type: u64 |
+ | Value: "42" | | Value: 42 |
+ +--------------------+ +---------------------+
| |
- | +---------------+
- | |
- V |
- +--------------------+ |
- | Counter sysfs |<-+
- +--------------------+
- | Translates to the |
- | standard Counter |
- | sysfs output |
- |--------------------|
- | Type: const char * |
- | Value: "42" |
- +--------------------+
- |
- ---------------
- / const char * /
- ---------------
+ --------------- ----------
+ / const char * / / u64 /
+ --------------- ----------
+ | |
+ | V
+ | +-----------+
+ | | read |
+ | +-----------+
+ | \ Count: 42 /
+ | -----------
|
V
+--------------------------------------------------+
@@ -426,7 +420,7 @@ driver is exemplified by the following::
\ Count: "42" /
--------------------------------------------------
-There are three primary components involved:
+There are four primary components involved:
Counter device driver
---------------------
@@ -446,3 +440,69 @@ and vice versa.
Please refer to the `Documentation/ABI/testing/sysfs-bus-counter` file
for a detailed breakdown of the available Generic Counter interface
sysfs attributes.
+
+Counter chrdev
+--------------
+Translates counter data to the standard Counter character device; data
+is transferred via standard character device read/write calls.
+
+Sysfs Interface
+===============
+
+Several sysfs attributes are generated by the Generic Counter interface,
+and reside under the `/sys/bus/counter/devices/counterX` directory,
+where `X` is to the respective counter device id. Please see
+Documentation/ABI/testing/sysfs-bus-counter for detailed information on
+each Generic Counter interface sysfs attribute.
+
+Through these sysfs attributes, programs and scripts may interact with
+the Generic Counter paradigm Counts, Signals, and Synapses of respective
+counter devices.
+
+Counter Character Device
+========================
+
+Counter character device nodes are created under the `/dev` directory as
+`counterX`, where `X` is the respective counter device id. Defines for
+the standard Counter data types are exposed via the userspace
+`include/uapi/linux/counter-types.h` file.
+
+A `/sys/bus/counter/devices/counterX/chrdev_format` sysfs attribute is
+available to expose the character device data format.
+
+Users may write to this sysfs attribute to select the components they
+want to interface -- the layout can be determined as well from the
+order. For example::
+
+# echo "C0 C3 C2" > /sys/bus/counter/devices/counter0/chrdev_format
+
+This would select Counts 0, 3, and 2 (in that order) to be available
+in the `/dev/counter0` node as a contiguous memory region.
+
+Users can select extensions in a similar fashion::
+
+# echo "C4E2 S1E0" > /sys/bus/counter/devices/counter0/chrdev_format
+
+This would select extension 2 from Count 4, and extension 0 from
+Signal 1.
+
+Users may read from this `chrdev_format` sysfs attribute in order to see
+the currently configured format of the character device.
+
+Users may perform read/write operations on the `/dev/counterX` node
+directly; the layout of the data is what they user has configured via
+the chrdev_format sysfs attribute. For example::
+
+# echo "C0 C1 S0 S1" > /sys/bus/counter/devices/counter0/chrdev_format
+
+Yields the following `/dev/counter0` memory layout::
+
+ +-----------------+------------------+----------+----------+
+ | Byte 0 - Byte 7 | Byte 8 - Byte 15 | Byte 16 | Byte 17 |
+ +-----------------+------------------+----------+----------+
+ | Count 0 | Count 1 | Signal 0 | Signal 2 |
+ +-----------------+------------------+----------+----------+
+
+The number of bytes allotted for each component or extension is
+determined by its respective data type: u8 will have 1 byte allotted,
+u64 will have 8 bytes allotted, etc.
--
2.26.2
^ permalink raw reply related [flat|nested] 10+ messages in thread
* Re: [PATCH v3 3/4] counter: Add character device interface
2020-06-17 1:40 ` [PATCH v3 3/4] counter: Add character device interface William Breathitt Gray
@ 2020-06-20 18:50 ` David Lechner
2020-06-21 19:53 ` William Breathitt Gray
0 siblings, 1 reply; 10+ messages in thread
From: David Lechner @ 2020-06-20 18:50 UTC (permalink / raw)
To: William Breathitt Gray, jic23
Cc: kamel.bouhara, gwendal, alexandre.belloni, linux-iio,
linux-kernel, linux-stm32, linux-arm-kernel, syednwaris,
patrick.havelange, fabrice.gasnier, mcoquelin.stm32,
alexandre.torgue
On 6/16/20 8:40 PM, William Breathitt Gray wrote:
> This patch introduces a character device interface for the Counter
> subsystem. Device control is exposed through standard character device
> read and write operations.
>
> A /sys/bus/counter/devices/counterX/chrdev_format sysfs attribute is
> introduced to expose the character device data format:
>
> * Users may write to this sysfs attribute to select the components they
> want to interface -- the layout can be determined as well from the
> order. For example:
>
> # echo "C0 C3 C2" > /sys/bus/counter/devices/counter0/chrdev_format
>
> This would select Counts 0, 3, and 2 (in that order) to be available
> in the /dev/counter0 node as a contiguous memory region.
>
> You can select extensions in a similar fashion:
>
> # echo "C4E2 S1E0" > /sys/bus/counter/devices/counter0/chrdev_format
>
> This would select extension 2 from Count 4, and extension 0 from
> Signal 1.
>
> * Users may read from this chrdev_format sysfs attribute in order to see
> the currently configured format of the character device.
>
> * Users may perform read/write operations on the /dev/counterX node
> directly; the layout of the data is what they user has configured via
> the chrdev_format sysfs attribute. For example:
>
> # echo "C0 C1 S0 S1" > /sys/bus/counter/devices/counter0/chrdev_format
>
> Yields the following /dev/counter0 memory layout:
>
> +-----------------+------------------+----------+----------+
> | Byte 0 - Byte 7 | Byte 8 - Byte 15 | Byte 16 | Byte 17 |
> +-----------------+------------------+----------+----------+
> | Count 0 | Count 1 | Signal 0 | Signal 2 |
> +-----------------+------------------+----------+----------+
>
> The number of bytes allotted for each component or extension is
> determined by its respective data type: u8 will have 1 byte allotted,
> u64 will have 8 bytes allotted, etc.
>
Instead of the proposed character device, I would really rather have one
that gives past events instead of the current state.
I have thought about some of the suggestions from previous version of
this patch series and I'm starting to think something similar to the
input and gpio subsystems would work fairly well.
There would have to be a fixed size event data structure:
struct counter_event {
/** Best approximation of when event occurred in nanoseconds. */
__u64 timestamp;
/**
* Description of the synapse that triggered the event and the
* signal/counter that the value represents.
*/
__u64 descriptor;
/** The signal/counter value recorded when the synapse fired. */
__u64 value;
};
The descriptor field would actually probably be a union of __u64 and a
struct with its own fields to describe the synapse and signal or count.
If a synapse involves more than one signal or count, then there would
be multiple events with identical timestamps.
Userspace programs should be able to enable only the events/synapses they
are interested in and then the poll() the character device to wait for
events in an efficient way instead of having to constantly read - which
could still miss events.
---
Real world use case - measuring the speed of a motor:
At low speeds it is more accurate to measure the time difference between
count events. In this case we would want events from two synapses. One
triggered by the rising and falling edges of signal A and one triggered
by the direction signal. The magnitude of the speed is calculated by
taking the difference in timestamps between signal A events and the +/-
sign is determined by the direction signal.
At high speeds a different configuration is needed. Assuming the counter
has a timer clock signal a synapse would be configured to fire every 10
or 20 milliseconds. This would trigger an event that contains the count.
The speed is calculated as the difference in counts divided by the fixed
time interval.
Some applications may need to do both and be able to change the
configuration at runtime. It may start out in the low speed configuration,
but as the speed increases, events triggered by the change in count will
need to be disabled to prevent being overwhelmed with too many count
events. But if the speed drops low again, the count events will need to
be turned back on.
---
Regarding the implementation, the character device can be backed by a
kfifo. Interrupts from the counter hardware push events to the kfifo
and reading from the character device drains the kfifo.
drivers/gpio/gpiolib.c could be a good example to follow.
If we only want to allow one consumer to open the chardev at a time,
then enabling/disabling events via sysfs would probably be fine since
we are already sort of doing that anyway to enable/disable counters.
But if we need to allow multiple consumers per chardev that would each
want different events, then configuring via ioctl would be required so
that per-file descriptor configuration could be done (each call to open()
would create a new kfifo and ioctl would configure what gets pushed to
that kfifo).
^ permalink raw reply [flat|nested] 10+ messages in thread
* Re: [PATCH v3 3/4] counter: Add character device interface
2020-06-20 18:50 ` David Lechner
@ 2020-06-21 19:53 ` William Breathitt Gray
2020-06-22 14:08 ` David Lechner
0 siblings, 1 reply; 10+ messages in thread
From: William Breathitt Gray @ 2020-06-21 19:53 UTC (permalink / raw)
To: David Lechner
Cc: jic23, kamel.bouhara, gwendal, alexandre.belloni, linux-iio,
linux-kernel, linux-stm32, linux-arm-kernel, syednwaris,
patrick.havelange, fabrice.gasnier, mcoquelin.stm32,
alexandre.torgue
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On Sat, Jun 20, 2020 at 01:50:59PM -0500, David Lechner wrote:
> On 6/16/20 8:40 PM, William Breathitt Gray wrote:
> > This patch introduces a character device interface for the Counter
> > subsystem. Device control is exposed through standard character device
> > read and write operations.
> >
> > A /sys/bus/counter/devices/counterX/chrdev_format sysfs attribute is
> > introduced to expose the character device data format:
> >
> > * Users may write to this sysfs attribute to select the components they
> > want to interface -- the layout can be determined as well from the
> > order. For example:
> >
> > # echo "C0 C3 C2" > /sys/bus/counter/devices/counter0/chrdev_format
> >
> > This would select Counts 0, 3, and 2 (in that order) to be available
> > in the /dev/counter0 node as a contiguous memory region.
> >
> > You can select extensions in a similar fashion:
> >
> > # echo "C4E2 S1E0" > /sys/bus/counter/devices/counter0/chrdev_format
> >
> > This would select extension 2 from Count 4, and extension 0 from
> > Signal 1.
> >
> > * Users may read from this chrdev_format sysfs attribute in order to see
> > the currently configured format of the character device.
> >
> > * Users may perform read/write operations on the /dev/counterX node
> > directly; the layout of the data is what they user has configured via
> > the chrdev_format sysfs attribute. For example:
> >
> > # echo "C0 C1 S0 S1" > /sys/bus/counter/devices/counter0/chrdev_format
> >
> > Yields the following /dev/counter0 memory layout:
> >
> > +-----------------+------------------+----------+----------+
> > | Byte 0 - Byte 7 | Byte 8 - Byte 15 | Byte 16 | Byte 17 |
> > +-----------------+------------------+----------+----------+
> > | Count 0 | Count 1 | Signal 0 | Signal 2 |
> > +-----------------+------------------+----------+----------+
> >
> > The number of bytes allotted for each component or extension is
> > determined by its respective data type: u8 will have 1 byte allotted,
> > u64 will have 8 bytes allotted, etc.
> >
>
> Instead of the proposed character device, I would really rather have one
> that gives past events instead of the current state.
>
> I have thought about some of the suggestions from previous version of
> this patch series and I'm starting to think something similar to the
> input and gpio subsystems would work fairly well.
>
>
> There would have to be a fixed size event data structure:
>
> struct counter_event {
> /** Best approximation of when event occurred in nanoseconds. */
> __u64 timestamp;
> /**
> * Description of the synapse that triggered the event and the
> * signal/counter that the value represents.
> */
> __u64 descriptor;
> /** The signal/counter value recorded when the synapse fired. */
> __u64 value;
> };
>
> The descriptor field would actually probably be a union of __u64 and a
> struct with its own fields to describe the synapse and signal or count.
>
> If a synapse involves more than one signal or count, then there would
> be multiple events with identical timestamps.
>
> Userspace programs should be able to enable only the events/synapses they
> are interested in and then the poll() the character device to wait for
> events in an efficient way instead of having to constantly read - which
> could still miss events.
>
> ---
>
> Real world use case - measuring the speed of a motor:
>
> At low speeds it is more accurate to measure the time difference between
> count events. In this case we would want events from two synapses. One
> triggered by the rising and falling edges of signal A and one triggered
> by the direction signal. The magnitude of the speed is calculated by
> taking the difference in timestamps between signal A events and the +/-
> sign is determined by the direction signal.
>
> At high speeds a different configuration is needed. Assuming the counter
> has a timer clock signal a synapse would be configured to fire every 10
> or 20 milliseconds. This would trigger an event that contains the count.
> The speed is calculated as the difference in counts divided by the fixed
> time interval.
>
> Some applications may need to do both and be able to change the
> configuration at runtime. It may start out in the low speed configuration,
> but as the speed increases, events triggered by the change in count will
> need to be disabled to prevent being overwhelmed with too many count
> events. But if the speed drops low again, the count events will need to
> be turned back on.
>
> ---
>
> Regarding the implementation, the character device can be backed by a
> kfifo. Interrupts from the counter hardware push events to the kfifo
> and reading from the character device drains the kfifo.
>
> drivers/gpio/gpiolib.c could be a good example to follow.
>
> If we only want to allow one consumer to open the chardev at a time,
> then enabling/disabling events via sysfs would probably be fine since
> we are already sort of doing that anyway to enable/disable counters.
> But if we need to allow multiple consumers per chardev that would each
> want different events, then configuring via ioctl would be required so
> that per-file descriptor configuration could be done (each call to open()
> would create a new kfifo and ioctl would configure what gets pushed to
> that kfifo).
Perhaps structuring the interface around events would be a good approach
afterall. The way I see it is that we have two types of use cases to
support: those that are sensitive to latency and those that are not. Use
cases where latency is not a concern can simply use the existing sysfs
interface, so really all we care about in this discussion are the
latency-sensitive use cases.
If a user cares about latency, I think it's because their use case
involves some sort of realtime deadline. In this kind of situation, I
suspect they will not simply be checking the current count in a loop,
but rather design their system around interrupts from the counter device
to notify their application when some deadline or condition has been
met.
Because a latency-conscious user would be waiting on events, the Counter
character device interface should be structured around configuring and
receiving events with respective data. The user should be able to choose
which events they want to receive, as well as the particular data they
want when that event occurs.
Synapses simply indicate a change in a Count value; every signal Count
value change is not necessarily interesting, so Counter events would
likely be defined separately from Synapses. Regardless, users would need
the ability to choose the particular data they want associated with a
particular event.
For example, in the dual-axes positioning table scenario, a user
application would likely want to know the exact X and Y position at the
time of a given event -- that means an event should provide two Count
values (and possibly associated device flags) when it occurs. I'm not
sure yet how the struct counter_event should be defined in order to
support this; we will need to indicate the format of data as well as
provide the data itself. Perhaps, we can handle this by providing an
unique id field so that only a single datum (e.g. a single count value)
is provided via the value field, but subsequent struct counter_event
items share the same id so that the user knows that a particular datum
is part of a larger group of data for a specific event.
William Breathitt Gray
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^ permalink raw reply [flat|nested] 10+ messages in thread
* Re: [PATCH v3 3/4] counter: Add character device interface
2020-06-21 19:53 ` William Breathitt Gray
@ 2020-06-22 14:08 ` David Lechner
2020-06-27 18:17 ` William Breathitt Gray
0 siblings, 1 reply; 10+ messages in thread
From: David Lechner @ 2020-06-22 14:08 UTC (permalink / raw)
To: William Breathitt Gray
Cc: jic23, kamel.bouhara, gwendal, alexandre.belloni, linux-iio,
linux-kernel, linux-stm32, linux-arm-kernel, syednwaris,
patrick.havelange, fabrice.gasnier, mcoquelin.stm32,
alexandre.torgue
On 6/21/20 2:53 PM, William Breathitt Gray wrote:
> Synapses simply indicate a change in a Count value
Ah, ok. I understand now that synapse is the wrong term for things like
the change in direction event or error events.
> For example, in the dual-axes positioning table scenario, a user
> application would likely want to know the exact X and Y position at the
> time of a given event -- that means an event should provide two Count
> values (and possibly associated device flags) when it occurs. I'm not
> sure yet how the struct counter_event should be defined in order to
> support this; we will need to indicate the format of data as well as
> provide the data itself. Perhaps, we can handle this by providing an
> unique id field so that only a single datum (e.g. a single count value)
> is provided via the value field, but subsequent struct counter_event
> items share the same id so that the user knows that a particular datum
> is part of a larger group of data for a specific event.
The timestamp could act as the "id" to correlate multiple values of a
single event.
^ permalink raw reply [flat|nested] 10+ messages in thread
* Re: [PATCH v3 3/4] counter: Add character device interface
2020-06-22 14:08 ` David Lechner
@ 2020-06-27 18:17 ` William Breathitt Gray
2020-06-27 19:20 ` David Lechner
0 siblings, 1 reply; 10+ messages in thread
From: William Breathitt Gray @ 2020-06-27 18:17 UTC (permalink / raw)
To: David Lechner
Cc: jic23, kamel.bouhara, gwendal, alexandre.belloni, linux-iio,
linux-kernel, linux-stm32, linux-arm-kernel, syednwaris,
patrick.havelange, fabrice.gasnier, mcoquelin.stm32,
alexandre.torgue
[-- Attachment #1: Type: text/plain, Size: 2819 bytes --]
On Mon, Jun 22, 2020 at 09:08:48AM -0500, David Lechner wrote:
> On 6/21/20 2:53 PM, William Breathitt Gray wrote:
> > For example, in the dual-axes positioning table scenario, a user
> > application would likely want to know the exact X and Y position at the
> > time of a given event -- that means an event should provide two Count
> > values (and possibly associated device flags) when it occurs. I'm not
> > sure yet how the struct counter_event should be defined in order to
> > support this; we will need to indicate the format of data as well as
> > provide the data itself. Perhaps, we can handle this by providing an
> > unique id field so that only a single datum (e.g. a single count value)
> > is provided via the value field, but subsequent struct counter_event
> > items share the same id so that the user knows that a particular datum
> > is part of a larger group of data for a specific event.
>
> The timestamp could act as the "id" to correlate multiple values of a
> single event.
Okay, I see how that can work. So the /dev/counterX character nodes
would return a stream of data structures that look something like this:
struct counter_event {
/**
* Best approximation of when event occurred in nanoseconds.
* Same timestamp value indicates data is part of same event.
*/
struct timeval time;
/**
* Type of event that triggered. This would correlate with the
* IRQ set up for the device.
*/
__u16 type;
/**
* Type of data represented by the value member. This enables
* the user to extract the right datatype from the value field.
*/
__u16 code;
/** The value recorded when the event fired. */
__u64 value;
};
In fact, this data structure looks a lot like struct input_event; would
it make sense to use that for this? I suppose we can't because we need
to support 64-bit value for our use cases.
Userspace also requires a way to enable the events and configure them to
report the data it wants. So perhaps the following sysfs attributes
would accomplish such:
* /sys/bus/devices/counterX/eventY_enable:
Users can enable/disable event Y.
* /sys/bus/devices/counterX/eventY_config:
Data to get when event Y is triggered (e.g. Counts, extensions, etc.).
Here's another concern for latency-sensitive applications: should we
handle writing data to the devices? While we have real-life examples of
latency-sensitive read operations, I'm not sure if a user will ever need
to write to a counter device within some realtime critical deadline --
I think write operations are primarily done for the purpose of
configuring the device for operation rather than during it. So perhaps
we don't need to worry about this use case because users can write data
via the existing sysfs interface.
William Breathitt Gray
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^ permalink raw reply [flat|nested] 10+ messages in thread
* Re: [PATCH v3 3/4] counter: Add character device interface
2020-06-27 18:17 ` William Breathitt Gray
@ 2020-06-27 19:20 ` David Lechner
0 siblings, 0 replies; 10+ messages in thread
From: David Lechner @ 2020-06-27 19:20 UTC (permalink / raw)
To: William Breathitt Gray
Cc: jic23, kamel.bouhara, gwendal, alexandre.belloni, linux-iio,
linux-kernel, linux-stm32, linux-arm-kernel, syednwaris,
patrick.havelange, fabrice.gasnier, mcoquelin.stm32,
alexandre.torgue
On 6/27/20 1:17 PM, William Breathitt Gray wrote:
> On Mon, Jun 22, 2020 at 09:08:48AM -0500, David Lechner wrote:
>> On 6/21/20 2:53 PM, William Breathitt Gray wrote:
>>> For example, in the dual-axes positioning table scenario, a user
>>> application would likely want to know the exact X and Y position at the
>>> time of a given event -- that means an event should provide two Count
>>> values (and possibly associated device flags) when it occurs. I'm not
>>> sure yet how the struct counter_event should be defined in order to
>>> support this; we will need to indicate the format of data as well as
>>> provide the data itself. Perhaps, we can handle this by providing an
>>> unique id field so that only a single datum (e.g. a single count value)
>>> is provided via the value field, but subsequent struct counter_event
>>> items share the same id so that the user knows that a particular datum
>>> is part of a larger group of data for a specific event.
>>
>> The timestamp could act as the "id" to correlate multiple values of a
>> single event.
>
> Okay, I see how that can work. So the /dev/counterX character nodes
> would return a stream of data structures that look something like this:
>
> struct counter_event {
> /**
> * Best approximation of when event occurred in nanoseconds.
> * Same timestamp value indicates data is part of same event.
> */
> struct timeval time;
> /**
> * Type of event that triggered. This would correlate with the
> * IRQ set up for the device.
> */
> __u16 type;
> /**
> * Type of data represented by the value member. This enables
> * the user to extract the right datatype from the value field.
> */
> __u16 code;
> /** The value recorded when the event fired. */
> __u64 value;
> };
>
> In fact, this data structure looks a lot like struct input_event; would
> it make sense to use that for this? I suppose we can't because we need
> to support 64-bit value for our use cases.
Yes, since counter is its own subsystem, it makes sense to have its own
data types.
>
> Userspace also requires a way to enable the events and configure them to
> report the data it wants. So perhaps the following sysfs attributes
> would accomplish such:
>
> * /sys/bus/devices/counterX/eventY_enable:
> Users can enable/disable event Y.
> * /sys/bus/devices/counterX/eventY_config:
> Data to get when event Y is triggered (e.g. Counts, extensions, etc.).
This is one of the questions I had too that I don't have a good answer to.
If we want to allow the use case of multiple "consumers" for a single
chardev where each consumer wants different events (e.g program X opens
/dev/counter0 and wants only events A and B while program Y opens the
same /dev/counter0 and wants only events A and C) then it would make
sense to use an ioctl for configuration of events so that each open
file descriptor could be configured differently.
But if we only want to allow one user of a counter, then configuring
via sysfs as you have suggested is probably fine.
I think I might make sense to us an ioctl in any case though if we are
going to use the same code values to configure the event.
>
> Here's another concern for latency-sensitive applications: should we
> handle writing data to the devices? While we have real-life examples of
> latency-sensitive read operations, I'm not sure if a user will ever need
> to write to a counter device within some realtime critical deadline --
> I think write operations are primarily done for the purpose of
> configuring the device for operation rather than during it. So perhaps
> we don't need to worry about this use case because users can write data
> via the existing sysfs interface.
Agreed.
^ permalink raw reply [flat|nested] 10+ messages in thread
end of thread, other threads:[~2020-06-27 19:21 UTC | newest]
Thread overview: 10+ messages (download: mbox.gz / follow: Atom feed)
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2020-06-17 1:39 [PATCH v3 0/4] Introduce the Counter character device interface William Breathitt Gray
2020-06-17 1:39 ` [PATCH v3 1/4] counter: Internalize sysfs interface code William Breathitt Gray
2020-06-17 1:40 ` [PATCH v3 2/4] docs: counter: Update to reflect sysfs internalization William Breathitt Gray
2020-06-17 1:40 ` [PATCH v3 3/4] counter: Add character device interface William Breathitt Gray
2020-06-20 18:50 ` David Lechner
2020-06-21 19:53 ` William Breathitt Gray
2020-06-22 14:08 ` David Lechner
2020-06-27 18:17 ` William Breathitt Gray
2020-06-27 19:20 ` David Lechner
2020-06-17 1:40 ` [PATCH v3 4/4] docs: counter: Document " William Breathitt Gray
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