* [PATCH v7 0/5] hwmon: ina2xx: implement chip reinitialization and add new attributes
@ 2014-12-13 16:27 Bartosz Golaszewski
2014-12-13 16:27 ` [PATCH v7 1/5] hwmon: ina2xx: reinitialize the chip in case it's been reset Bartosz Golaszewski
` (5 more replies)
0 siblings, 6 replies; 8+ messages in thread
From: Bartosz Golaszewski @ 2014-12-13 16:27 UTC (permalink / raw)
To: Guenter Roeck
Cc: LKML, Benoit Cousson, Patrick Titiano, LM Sensors, Bartosz Golaszewski
This series implements a mechanism to detect if the chip is in its POR state
and reinitialize it if needed. It also extends the sysfs interface to make the
driver configurable at run-time.
The shunt_resistor attribute allows to change the shunt resistance value
at run-time in cases where ina2xx used to do the measurement isn't integrated
with the shunt.
The avg_rate attribute allows to increase/decrease noise reduction.
v7:
- implemented a retry counter for the reinitialization procedure
- using msleep() (since the sleep is > 20ms) instead of mdelay()
when waiting for the chip update
v6:
https://www.mail-archive.com/linux-kernel%40vger.kernel.org/msg787390.html
Bartosz Golaszewski (5):
hwmon: ina2xx: reinitialize the chip in case it's been reset
hwmon: ina2xx: remove a stray new line
hwmon: ina2xx: don't accept shunt values greater than the calibration factor
hwmon: ina2xx: make shunt resistance configurable at run-time
hwmon: ina2xx: allow to change the averaging rate at run-time
Documentation/hwmon/ina2xx | 8 +-
drivers/hwmon/ina2xx.c | 304 +++++++++++++++++++++++++++++++++++++++------
2 files changed, 269 insertions(+), 43 deletions(-)
--
2.1.3
^ permalink raw reply [flat|nested] 8+ messages in thread
* [PATCH v7 1/5] hwmon: ina2xx: reinitialize the chip in case it's been reset
2014-12-13 16:27 [PATCH v7 0/5] hwmon: ina2xx: implement chip reinitialization and add new attributes Bartosz Golaszewski
@ 2014-12-13 16:27 ` Bartosz Golaszewski
2014-12-13 16:27 ` [PATCH v7 2/5] hwmon: ina2xx: remove a stray new line Bartosz Golaszewski
` (4 subsequent siblings)
5 siblings, 0 replies; 8+ messages in thread
From: Bartosz Golaszewski @ 2014-12-13 16:27 UTC (permalink / raw)
To: Guenter Roeck
Cc: LKML, Benoit Cousson, Patrick Titiano, LM Sensors, Bartosz Golaszewski
Chips from the ina family don't like to be uninitialized. In case the power
is cut-off and restored again the calibration register will be reset
to 0 and both the power and current registers will remain at 0.
Check the calibration register in ina2xx_update_device() and reinitialize
the chip if needed.
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
---
drivers/hwmon/ina2xx.c | 128 +++++++++++++++++++++++++++++++++++--------------
1 file changed, 91 insertions(+), 37 deletions(-)
diff --git a/drivers/hwmon/ina2xx.c b/drivers/hwmon/ina2xx.c
index e01feba..ffbd60f 100644
--- a/drivers/hwmon/ina2xx.c
+++ b/drivers/hwmon/ina2xx.c
@@ -35,6 +35,7 @@
#include <linux/hwmon-sysfs.h>
#include <linux/jiffies.h>
#include <linux/of.h>
+#include <linux/delay.h>
#include <linux/platform_data/ina2xx.h>
@@ -64,6 +65,9 @@
/* worst case is 68.10 ms (~14.6Hz, ina219) */
#define INA2XX_CONVERSION_RATE 15
+#define INA2XX_MAX_DELAY 69 /* worst case delay in ms */
+
+#define INA2XX_RSHUNT_DEFAULT 10000
enum ina2xx_ids { ina219, ina226 };
@@ -81,6 +85,8 @@ struct ina2xx_data {
struct i2c_client *client;
const struct ina2xx_config *config;
+ long rshunt;
+
struct mutex update_lock;
bool valid;
unsigned long last_updated;
@@ -110,34 +116,96 @@ static const struct ina2xx_config ina2xx_config[] = {
},
};
-static struct ina2xx_data *ina2xx_update_device(struct device *dev)
+/*
+ * Initialize the configuration and calibration registers.
+ */
+static int ina2xx_init(struct ina2xx_data *data)
{
- struct ina2xx_data *data = dev_get_drvdata(dev);
struct i2c_client *client = data->client;
- struct ina2xx_data *ret = data;
+ int ret;
- mutex_lock(&data->update_lock);
+ /* device configuration */
+ ret = i2c_smbus_write_word_swapped(client, INA2XX_CONFIG,
+ data->config->config_default);
+ if (ret < 0)
+ return ret;
- if (time_after(jiffies, data->last_updated +
- HZ / INA2XX_CONVERSION_RATE) || !data->valid) {
+ /*
+ * Set current LSB to 1mA, shunt is in uOhms
+ * (equation 13 in datasheet).
+ */
+ return i2c_smbus_write_word_swapped(client, INA2XX_CALIBRATION,
+ data->config->calibration_factor / data->rshunt);
+}
- int i;
+static int ina2xx_do_update(struct device *dev)
+{
+ struct ina2xx_data *data = dev_get_drvdata(dev);
+ struct i2c_client *client = data->client;
+ int i, rv, retry;
- dev_dbg(&client->dev, "Starting ina2xx update\n");
+ dev_dbg(&client->dev, "Starting ina2xx update\n");
+ for (retry = 5; retry; retry--) {
/* Read all registers */
for (i = 0; i < data->config->registers; i++) {
- int rv = i2c_smbus_read_word_swapped(client, i);
- if (rv < 0) {
- ret = ERR_PTR(rv);
- goto abort;
- }
+ rv = i2c_smbus_read_word_swapped(client, i);
+ if (rv < 0)
+ return rv;
data->regs[i] = rv;
}
+
+ /*
+ * If the current value in the calibration register is 0, the
+ * power and current registers will also remain at 0. In case
+ * the chip has been reset let's check the calibration
+ * register and reinitialize if needed.
+ */
+ if (data->regs[INA2XX_CALIBRATION] == 0) {
+ dev_warn(dev, "chip not calibrated, reinitializing\n");
+
+ rv = ina2xx_init(data);
+ if (rv < 0)
+ return rv;
+
+ /*
+ * Let's make sure the power and current registers
+ * have been updated before trying again.
+ */
+ msleep(INA2XX_MAX_DELAY);
+ continue;
+ }
+
data->last_updated = jiffies;
data->valid = 1;
+
+ return 0;
}
-abort:
+
+ /*
+ * If we're here then although all write operations succeeded, the
+ * chip still returns 0 in the calibration register. Nothing more we
+ * can do here.
+ */
+ dev_err(dev, "unable to reinitialize the chip\n");
+ return -ENODEV;
+}
+
+static struct ina2xx_data *ina2xx_update_device(struct device *dev)
+{
+ struct ina2xx_data *data = dev_get_drvdata(dev);
+ struct ina2xx_data *ret = data;
+ int rv;
+
+ mutex_lock(&data->update_lock);
+
+ if (time_after(jiffies, data->last_updated +
+ HZ / INA2XX_CONVERSION_RATE) || !data->valid) {
+ rv = ina2xx_do_update(dev);
+ if (rv < 0)
+ ret = ERR_PTR(rv);
+ }
+
mutex_unlock(&data->update_lock);
return ret;
}
@@ -221,7 +289,6 @@ static int ina2xx_probe(struct i2c_client *client,
struct device *dev = &client->dev;
struct ina2xx_data *data;
struct device *hwmon_dev;
- long shunt = 10000; /* default shunt value 10mOhms */
u32 val;
int ret;
@@ -234,41 +301,28 @@ static int ina2xx_probe(struct i2c_client *client,
if (dev_get_platdata(dev)) {
pdata = dev_get_platdata(dev);
- shunt = pdata->shunt_uohms;
+ data->rshunt = pdata->shunt_uohms;
} else if (!of_property_read_u32(dev->of_node,
"shunt-resistor", &val)) {
- shunt = val;
+ data->rshunt = val;
+ } else {
+ data->rshunt = INA2XX_RSHUNT_DEFAULT;
}
- if (shunt <= 0)
- return -ENODEV;
-
/* set the device type */
data->kind = id->driver_data;
data->config = &ina2xx_config[data->kind];
+ data->client = client;
- /* device configuration */
- ret = i2c_smbus_write_word_swapped(client, INA2XX_CONFIG,
- data->config->config_default);
- if (ret < 0) {
- dev_err(dev,
- "error writing to the config register: %d", ret);
+ if (data->rshunt <= 0)
return -ENODEV;
- }
- /*
- * Set current LSB to 1mA, shunt is in uOhms
- * (equation 13 in datasheet).
- */
- ret = i2c_smbus_write_word_swapped(client, INA2XX_CALIBRATION,
- data->config->calibration_factor / shunt);
+ ret = ina2xx_init(data);
if (ret < 0) {
- dev_err(dev,
- "error writing to the calibration register: %d", ret);
+ dev_err(dev, "error configuring the device: %d\n", ret);
return -ENODEV;
}
- data->client = client;
mutex_init(&data->update_lock);
hwmon_dev = devm_hwmon_device_register_with_groups(dev, client->name,
@@ -277,7 +331,7 @@ static int ina2xx_probe(struct i2c_client *client,
return PTR_ERR(hwmon_dev);
dev_info(dev, "power monitor %s (Rshunt = %li uOhm)\n",
- id->name, shunt);
+ id->name, data->rshunt);
return 0;
}
--
2.1.3
^ permalink raw reply related [flat|nested] 8+ messages in thread
* [PATCH v7 2/5] hwmon: ina2xx: remove a stray new line
2014-12-13 16:27 [PATCH v7 0/5] hwmon: ina2xx: implement chip reinitialization and add new attributes Bartosz Golaszewski
2014-12-13 16:27 ` [PATCH v7 1/5] hwmon: ina2xx: reinitialize the chip in case it's been reset Bartosz Golaszewski
@ 2014-12-13 16:27 ` Bartosz Golaszewski
2014-12-13 16:27 ` [PATCH v7 3/5] hwmon: ina2xx: don't accept shunt values greater than the calibration factor Bartosz Golaszewski
` (3 subsequent siblings)
5 siblings, 0 replies; 8+ messages in thread
From: Bartosz Golaszewski @ 2014-12-13 16:27 UTC (permalink / raw)
To: Guenter Roeck
Cc: LKML, Benoit Cousson, Patrick Titiano, LM Sensors, Bartosz Golaszewski
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
---
drivers/hwmon/ina2xx.c | 1 -
1 file changed, 1 deletion(-)
diff --git a/drivers/hwmon/ina2xx.c b/drivers/hwmon/ina2xx.c
index ffbd60f..39e017b 100644
--- a/drivers/hwmon/ina2xx.c
+++ b/drivers/hwmon/ina2xx.c
@@ -52,7 +52,6 @@
#define INA226_ALERT_LIMIT 0x07
#define INA226_DIE_ID 0xFF
-
/* register count */
#define INA219_REGISTERS 6
#define INA226_REGISTERS 8
--
2.1.3
^ permalink raw reply related [flat|nested] 8+ messages in thread
* [PATCH v7 3/5] hwmon: ina2xx: don't accept shunt values greater than the calibration factor
2014-12-13 16:27 [PATCH v7 0/5] hwmon: ina2xx: implement chip reinitialization and add new attributes Bartosz Golaszewski
2014-12-13 16:27 ` [PATCH v7 1/5] hwmon: ina2xx: reinitialize the chip in case it's been reset Bartosz Golaszewski
2014-12-13 16:27 ` [PATCH v7 2/5] hwmon: ina2xx: remove a stray new line Bartosz Golaszewski
@ 2014-12-13 16:27 ` Bartosz Golaszewski
2014-12-13 16:27 ` [PATCH v7 4/5] hwmon: ina2xx: make shunt resistance configurable at run-time Bartosz Golaszewski
` (2 subsequent siblings)
5 siblings, 0 replies; 8+ messages in thread
From: Bartosz Golaszewski @ 2014-12-13 16:27 UTC (permalink / raw)
To: Guenter Roeck
Cc: LKML, Benoit Cousson, Patrick Titiano, LM Sensors, Bartosz Golaszewski
Shunt resistance values greater than the chip's calibration factor make no
sense since the actual value written to the register equals:
<calibration factor> / <shunt>
Bail-out from ina2xx_probe() if the configured value is greater than the
calibration factor.
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
---
drivers/hwmon/ina2xx.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/hwmon/ina2xx.c b/drivers/hwmon/ina2xx.c
index 39e017b..3234e57 100644
--- a/drivers/hwmon/ina2xx.c
+++ b/drivers/hwmon/ina2xx.c
@@ -313,7 +313,8 @@ static int ina2xx_probe(struct i2c_client *client,
data->config = &ina2xx_config[data->kind];
data->client = client;
- if (data->rshunt <= 0)
+ if (data->rshunt <= 0 ||
+ data->rshunt > data->config->calibration_factor)
return -ENODEV;
ret = ina2xx_init(data);
--
2.1.3
^ permalink raw reply related [flat|nested] 8+ messages in thread
* [PATCH v7 4/5] hwmon: ina2xx: make shunt resistance configurable at run-time
2014-12-13 16:27 [PATCH v7 0/5] hwmon: ina2xx: implement chip reinitialization and add new attributes Bartosz Golaszewski
` (2 preceding siblings ...)
2014-12-13 16:27 ` [PATCH v7 3/5] hwmon: ina2xx: don't accept shunt values greater than the calibration factor Bartosz Golaszewski
@ 2014-12-13 16:27 ` Bartosz Golaszewski
2014-12-13 16:27 ` [PATCH v7 5/5] hwmon: ina2xx: allow to change the averaging rate " Bartosz Golaszewski
2014-12-20 3:23 ` [PATCH v7 0/5] hwmon: ina2xx: implement chip reinitialization and add new attributes Guenter Roeck
5 siblings, 0 replies; 8+ messages in thread
From: Bartosz Golaszewski @ 2014-12-13 16:27 UTC (permalink / raw)
To: Guenter Roeck
Cc: LKML, Benoit Cousson, Patrick Titiano, LM Sensors, Bartosz Golaszewski
The shunt resistance can only be set via platform_data or device tree. This
isn't suitable for devices in which the shunt resistance can change/isn't
known at boot-time.
Add a sysfs attribute that allows to read and set the shunt resistance.
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
---
Documentation/hwmon/ina2xx | 5 +++--
drivers/hwmon/ina2xx.c | 48 ++++++++++++++++++++++++++++++++++++++++++++--
2 files changed, 49 insertions(+), 4 deletions(-)
diff --git a/Documentation/hwmon/ina2xx b/Documentation/hwmon/ina2xx
index 4223c2d..320dd69 100644
--- a/Documentation/hwmon/ina2xx
+++ b/Documentation/hwmon/ina2xx
@@ -44,6 +44,7 @@ The INA226 monitors both a shunt voltage drop and bus supply voltage.
The INA230 is a high or low side current shunt and power monitor with an I2C
interface. The INA230 monitors both a shunt voltage drop and bus supply voltage.
-The shunt value in micro-ohms can be set via platform data or device tree.
-Please refer to the Documentation/devicetree/bindings/i2c/ina2xx.txt for bindings
+The shunt value in micro-ohms can be set via platform data or device tree at
+compile-time or via the shunt_resistor attribute in sysfs at run-time. Please
+refer to the Documentation/devicetree/bindings/i2c/ina2xx.txt for bindings
if the device tree is used.
diff --git a/drivers/hwmon/ina2xx.c b/drivers/hwmon/ina2xx.c
index 3234e57..49537ea 100644
--- a/drivers/hwmon/ina2xx.c
+++ b/drivers/hwmon/ina2xx.c
@@ -115,6 +115,12 @@ static const struct ina2xx_config ina2xx_config[] = {
},
};
+static int ina2xx_calibrate(struct ina2xx_data *data)
+{
+ return i2c_smbus_write_word_swapped(data->client, INA2XX_CALIBRATION,
+ data->config->calibration_factor / data->rshunt);
+}
+
/*
* Initialize the configuration and calibration registers.
*/
@@ -133,8 +139,7 @@ static int ina2xx_init(struct ina2xx_data *data)
* Set current LSB to 1mA, shunt is in uOhms
* (equation 13 in datasheet).
*/
- return i2c_smbus_write_word_swapped(client, INA2XX_CALIBRATION,
- data->config->calibration_factor / data->rshunt);
+ return ina2xx_calibrate(data);
}
static int ina2xx_do_update(struct device *dev)
@@ -231,6 +236,9 @@ static int ina2xx_get_value(struct ina2xx_data *data, u8 reg)
/* signed register, LSB=1mA (selected), in mA */
val = (s16)data->regs[reg];
break;
+ case INA2XX_CALIBRATION:
+ val = data->config->calibration_factor / data->regs[reg];
+ break;
default:
/* programmer goofed */
WARN_ON_ONCE(1);
@@ -254,6 +262,36 @@ static ssize_t ina2xx_show_value(struct device *dev,
ina2xx_get_value(data, attr->index));
}
+static ssize_t ina2xx_set_shunt(struct device *dev,
+ struct device_attribute *da,
+ const char *buf, size_t count)
+{
+ struct ina2xx_data *data = ina2xx_update_device(dev);
+ unsigned long val;
+ int status;
+
+ if (IS_ERR(data))
+ return PTR_ERR(data);
+
+ status = kstrtoul(buf, 10, &val);
+ if (status < 0)
+ return status;
+
+ if (val == 0 ||
+ /* Values greater than the calibration factor make no sense. */
+ val > data->config->calibration_factor)
+ return -EINVAL;
+
+ mutex_lock(&data->update_lock);
+ data->rshunt = val;
+ status = ina2xx_calibrate(data);
+ mutex_unlock(&data->update_lock);
+ if (status < 0)
+ return status;
+
+ return count;
+}
+
/* shunt voltage */
static SENSOR_DEVICE_ATTR(in0_input, S_IRUGO, ina2xx_show_value, NULL,
INA2XX_SHUNT_VOLTAGE);
@@ -270,12 +308,18 @@ static SENSOR_DEVICE_ATTR(curr1_input, S_IRUGO, ina2xx_show_value, NULL,
static SENSOR_DEVICE_ATTR(power1_input, S_IRUGO, ina2xx_show_value, NULL,
INA2XX_POWER);
+/* shunt resistance */
+static SENSOR_DEVICE_ATTR(shunt_resistor, S_IRUGO | S_IWUSR,
+ ina2xx_show_value, ina2xx_set_shunt,
+ INA2XX_CALIBRATION);
+
/* pointers to created device attributes */
static struct attribute *ina2xx_attrs[] = {
&sensor_dev_attr_in0_input.dev_attr.attr,
&sensor_dev_attr_in1_input.dev_attr.attr,
&sensor_dev_attr_curr1_input.dev_attr.attr,
&sensor_dev_attr_power1_input.dev_attr.attr,
+ &sensor_dev_attr_shunt_resistor.dev_attr.attr,
NULL,
};
ATTRIBUTE_GROUPS(ina2xx);
--
2.1.3
^ permalink raw reply related [flat|nested] 8+ messages in thread
* [PATCH v7 5/5] hwmon: ina2xx: allow to change the averaging rate at run-time
2014-12-13 16:27 [PATCH v7 0/5] hwmon: ina2xx: implement chip reinitialization and add new attributes Bartosz Golaszewski
` (3 preceding siblings ...)
2014-12-13 16:27 ` [PATCH v7 4/5] hwmon: ina2xx: make shunt resistance configurable at run-time Bartosz Golaszewski
@ 2014-12-13 16:27 ` Bartosz Golaszewski
2014-12-21 16:36 ` [v7, " Guenter Roeck
2014-12-20 3:23 ` [PATCH v7 0/5] hwmon: ina2xx: implement chip reinitialization and add new attributes Guenter Roeck
5 siblings, 1 reply; 8+ messages in thread
From: Bartosz Golaszewski @ 2014-12-13 16:27 UTC (permalink / raw)
To: Guenter Roeck
Cc: LKML, Benoit Cousson, Patrick Titiano, LM Sensors, Bartosz Golaszewski
The averaging rate of ina226 is hardcoded to 16 in the driver. Make it
modifiable at run-time via a new sysfs attribute.
While we're at it - add an additional variable to ina2xx_data, which holds
the current configuration settings - this way we'll be able to restore the
configuration in case of an unexpected chip reset.
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
---
Documentation/hwmon/ina2xx | 3 ++
drivers/hwmon/ina2xx.c | 132 +++++++++++++++++++++++++++++++++++++++++++--
2 files changed, 131 insertions(+), 4 deletions(-)
diff --git a/Documentation/hwmon/ina2xx b/Documentation/hwmon/ina2xx
index 320dd69..a11256d 100644
--- a/Documentation/hwmon/ina2xx
+++ b/Documentation/hwmon/ina2xx
@@ -48,3 +48,6 @@ The shunt value in micro-ohms can be set via platform data or device tree at
compile-time or via the shunt_resistor attribute in sysfs at run-time. Please
refer to the Documentation/devicetree/bindings/i2c/ina2xx.txt for bindings
if the device tree is used.
+
+The averaging rate of INA226 and INA230 can be changed via the avg_rate sysfs
+attribute. The available rates are: 1, 4, 16, 64, 128, 256, 512 and 1024.
diff --git a/drivers/hwmon/ina2xx.c b/drivers/hwmon/ina2xx.c
index 49537ea..d6fccad 100644
--- a/drivers/hwmon/ina2xx.c
+++ b/drivers/hwmon/ina2xx.c
@@ -68,6 +68,15 @@
#define INA2XX_RSHUNT_DEFAULT 10000
+/* bit masks for the averaging setting in the configuration register */
+#define INA226_AVG_RD_MASK 0x0E00
+#define INA226_AVG_WR_MASK 0xF1FF
+
+#define INA226_READ_AVG(reg) ((reg & INA226_AVG_RD_MASK) >> 9)
+
+/* common attrs, ina226 attrs and NULL */
+#define INA2XX_MAX_ATTRIBUTE_GROUPS 3
+
enum ina2xx_ids { ina219, ina226 };
struct ina2xx_config {
@@ -85,12 +94,14 @@ struct ina2xx_data {
const struct ina2xx_config *config;
long rshunt;
+ u16 curr_config;
struct mutex update_lock;
bool valid;
unsigned long last_updated;
int kind;
+ const struct attribute_group *groups[INA2XX_MAX_ATTRIBUTE_GROUPS];
u16 regs[INA2XX_MAX_REGISTERS];
};
@@ -115,6 +126,38 @@ static const struct ina2xx_config ina2xx_config[] = {
},
};
+/*
+ * Available averaging rates for ina226. The indices correspond with
+ * the bit values expected by the chip (according to the ina226 datasheet,
+ * table 3 AVG bit settings, found at
+ * http://www.ti.com/lit/ds/symlink/ina226.pdf.
+ */
+static const int ina226_avg_tab[] = { 1, 4, 16, 64, 128, 256, 512, 1024 };
+
+static int ina226_avg_bits(int avg)
+{
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(ina226_avg_tab); i++) {
+ if (avg == ina226_avg_tab[i])
+ return i;
+ }
+
+ return -EINVAL;
+}
+
+static int ina226_avg_val(int bits)
+{
+ /*
+ * Value read from the config register should be correct, but do check
+ * the boundary just in case.
+ */
+ if (bits >= ARRAY_SIZE(ina226_avg_tab))
+ return -ENODEV;
+
+ return ina226_avg_tab[bits];
+}
+
static int ina2xx_calibrate(struct ina2xx_data *data)
{
return i2c_smbus_write_word_swapped(data->client, INA2XX_CALIBRATION,
@@ -131,7 +174,7 @@ static int ina2xx_init(struct ina2xx_data *data)
/* device configuration */
ret = i2c_smbus_write_word_swapped(client, INA2XX_CONFIG,
- data->config->config_default);
+ data->curr_config);
if (ret < 0)
return ret;
@@ -292,6 +335,66 @@ static ssize_t ina2xx_set_shunt(struct device *dev,
return count;
}
+static ssize_t ina226_show_avg(struct device *dev,
+ struct device_attribute *da, char *buf)
+{
+ struct ina2xx_data *data = ina2xx_update_device(dev);
+ int avg, i, written = 0;
+ const char *fmt;
+
+ if (IS_ERR(data))
+ return PTR_ERR(data);
+
+ avg = ina226_avg_val(INA226_READ_AVG(data->regs[INA2XX_CONFIG]));
+ if (avg < 0)
+ return avg;
+
+ for (i = 0; i < ARRAY_SIZE(ina226_avg_tab); i++) {
+ if (avg == ina226_avg_tab[i])
+ fmt = "\t[%d]";
+ else
+ fmt = "\t%d";
+
+ written += snprintf(buf + written, PAGE_SIZE - written,
+ fmt, ina226_avg_tab[i]);
+ }
+ written += snprintf(buf + written, PAGE_SIZE - written, "\n");
+
+ return written;
+}
+
+static ssize_t ina226_set_avg(struct device *dev,
+ struct device_attribute *da,
+ const char *buf, size_t count)
+{
+ struct ina2xx_data *data = ina2xx_update_device(dev);
+ long val;
+ int status, avg;
+
+ if (IS_ERR(data))
+ return PTR_ERR(data);
+
+ status = kstrtol(buf, 10, &val);
+ if (status < 0)
+ return status;
+
+ avg = ina226_avg_bits(val);
+ if (avg < 0)
+ return avg;
+
+ mutex_lock(&data->update_lock);
+ data->curr_config = (data->regs[INA2XX_CONFIG] &
+ INA226_AVG_WR_MASK) | (avg << 9);
+ status = i2c_smbus_write_word_swapped(data->client,
+ INA2XX_CONFIG,
+ data->curr_config);
+ mutex_unlock(&data->update_lock);
+ if (status < 0)
+ return status;
+
+ return count;
+}
+
/* shunt voltage */
static SENSOR_DEVICE_ATTR(in0_input, S_IRUGO, ina2xx_show_value, NULL,
INA2XX_SHUNT_VOLTAGE);
@@ -313,6 +416,10 @@ static SENSOR_DEVICE_ATTR(shunt_resistor, S_IRUGO | S_IWUSR,
ina2xx_show_value, ina2xx_set_shunt,
INA2XX_CALIBRATION);
+/* averaging rate */
+static SENSOR_DEVICE_ATTR(avg_rate, S_IRUGO | S_IWUSR,
+ ina226_show_avg, ina226_set_avg, 0);
+
/* pointers to created device attributes */
static struct attribute *ina2xx_attrs[] = {
&sensor_dev_attr_in0_input.dev_attr.attr,
@@ -322,7 +429,19 @@ static struct attribute *ina2xx_attrs[] = {
&sensor_dev_attr_shunt_resistor.dev_attr.attr,
NULL,
};
-ATTRIBUTE_GROUPS(ina2xx);
+
+static const struct attribute_group ina2xx_group = {
+ .attrs = ina2xx_attrs,
+};
+
+static struct attribute *ina226_attrs[] = {
+ &sensor_dev_attr_avg_rate.dev_attr.attr,
+ NULL,
+};
+
+static const struct attribute_group ina226_group = {
+ .attrs = ina226_attrs,
+};
static int ina2xx_probe(struct i2c_client *client,
const struct i2c_device_id *id)
@@ -333,7 +452,7 @@ static int ina2xx_probe(struct i2c_client *client,
struct ina2xx_data *data;
struct device *hwmon_dev;
u32 val;
- int ret;
+ int ret, group = 0;
if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_WORD_DATA))
return -ENODEV;
@@ -355,6 +474,7 @@ static int ina2xx_probe(struct i2c_client *client,
/* set the device type */
data->kind = id->driver_data;
data->config = &ina2xx_config[data->kind];
+ data->curr_config = data->config->config_default;
data->client = client;
if (data->rshunt <= 0 ||
@@ -369,8 +489,12 @@ static int ina2xx_probe(struct i2c_client *client,
mutex_init(&data->update_lock);
+ data->groups[group++] = &ina2xx_group;
+ if (data->kind == ina226)
+ data->groups[group++] = &ina226_group;
+
hwmon_dev = devm_hwmon_device_register_with_groups(dev, client->name,
- data, ina2xx_groups);
+ data, data->groups);
if (IS_ERR(hwmon_dev))
return PTR_ERR(hwmon_dev);
--
2.1.3
^ permalink raw reply related [flat|nested] 8+ messages in thread
* Re: [PATCH v7 0/5] hwmon: ina2xx: implement chip reinitialization and add new attributes
2014-12-13 16:27 [PATCH v7 0/5] hwmon: ina2xx: implement chip reinitialization and add new attributes Bartosz Golaszewski
` (4 preceding siblings ...)
2014-12-13 16:27 ` [PATCH v7 5/5] hwmon: ina2xx: allow to change the averaging rate " Bartosz Golaszewski
@ 2014-12-20 3:23 ` Guenter Roeck
5 siblings, 0 replies; 8+ messages in thread
From: Guenter Roeck @ 2014-12-20 3:23 UTC (permalink / raw)
To: Bartosz Golaszewski; +Cc: LKML, Benoit Cousson, Patrick Titiano, LM Sensors
On 12/13/2014 08:27 AM, Bartosz Golaszewski wrote:
> This series implements a mechanism to detect if the chip is in its POR state
> and reinitialize it if needed. It also extends the sysfs interface to make the
> driver configurable at run-time.
>
> The shunt_resistor attribute allows to change the shunt resistance value
> at run-time in cases where ina2xx used to do the measurement isn't integrated
> with the shunt.
>
> The avg_rate attribute allows to increase/decrease noise reduction.
>
> v7:
> - implemented a retry counter for the reinitialization procedure
> - using msleep() (since the sleep is > 20ms) instead of mdelay()
> when waiting for the chip update
>
> v6:
> https://www.mail-archive.com/linux-kernel%40vger.kernel.org/msg787390.html
>
> Bartosz Golaszewski (5):
> hwmon: ina2xx: reinitialize the chip in case it's been reset
> hwmon: ina2xx: remove a stray new line
> hwmon: ina2xx: don't accept shunt values greater than the calibration factor
> hwmon: ina2xx: make shunt resistance configurable at run-time
> hwmon: ina2xx: allow to change the averaging rate at run-time
>
> Documentation/hwmon/ina2xx | 8 +-
> drivers/hwmon/ina2xx.c | 304 +++++++++++++++++++++++++++++++++++++++------
> 2 files changed, 269 insertions(+), 43 deletions(-)
>
I didn't forget those patches; I have been busy in the last couple of weeks.
Also, I'll be out for the next two weeks. I'll look into the patches after
I am back.
Guenter
^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [v7, 5/5] hwmon: ina2xx: allow to change the averaging rate at run-time
2014-12-13 16:27 ` [PATCH v7 5/5] hwmon: ina2xx: allow to change the averaging rate " Bartosz Golaszewski
@ 2014-12-21 16:36 ` Guenter Roeck
0 siblings, 0 replies; 8+ messages in thread
From: Guenter Roeck @ 2014-12-21 16:36 UTC (permalink / raw)
To: Bartosz Golaszewski; +Cc: Patrick Titiano, LKML, Benoit Cousson, LM Sensors
On Sat, Dec 13, 2014 at 05:27:21PM +0100, Bartosz Golaszewski wrote:
> The averaging rate of ina226 is hardcoded to 16 in the driver. Make it
> modifiable at run-time via a new sysfs attribute.
>
> While we're at it - add an additional variable to ina2xx_data, which holds
> the current configuration settings - this way we'll be able to restore the
> configuration in case of an unexpected chip reset.
>
> Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
> ---
> Documentation/hwmon/ina2xx | 3 ++
> drivers/hwmon/ina2xx.c | 132 +++++++++++++++++++++++++++++++++++++++++++--
> 2 files changed, 131 insertions(+), 4 deletions(-)
>
> diff --git a/Documentation/hwmon/ina2xx b/Documentation/hwmon/ina2xx
> index 320dd69..a11256d 100644
> --- a/Documentation/hwmon/ina2xx
> +++ b/Documentation/hwmon/ina2xx
> @@ -48,3 +48,6 @@ The shunt value in micro-ohms can be set via platform data or device tree at
> compile-time or via the shunt_resistor attribute in sysfs at run-time. Please
> refer to the Documentation/devicetree/bindings/i2c/ina2xx.txt for bindings
> if the device tree is used.
> +
> +The averaging rate of INA226 and INA230 can be changed via the avg_rate sysfs
> +attribute. The available rates are: 1, 4, 16, 64, 128, 256, 512 and 1024.
> diff --git a/drivers/hwmon/ina2xx.c b/drivers/hwmon/ina2xx.c
> index 49537ea..d6fccad 100644
> --- a/drivers/hwmon/ina2xx.c
> +++ b/drivers/hwmon/ina2xx.c
> @@ -68,6 +68,15 @@
>
> #define INA2XX_RSHUNT_DEFAULT 10000
>
> +/* bit masks for the averaging setting in the configuration register */
> +#define INA226_AVG_RD_MASK 0x0E00
> +#define INA226_AVG_WR_MASK 0xF1FF
> +
> +#define INA226_READ_AVG(reg) ((reg & INA226_AVG_RD_MASK) >> 9)
> +
> +/* common attrs, ina226 attrs and NULL */
> +#define INA2XX_MAX_ATTRIBUTE_GROUPS 3
> +
> enum ina2xx_ids { ina219, ina226 };
>
> struct ina2xx_config {
> @@ -85,12 +94,14 @@ struct ina2xx_data {
> const struct ina2xx_config *config;
>
> long rshunt;
> + u16 curr_config;
>
> struct mutex update_lock;
> bool valid;
> unsigned long last_updated;
>
> int kind;
> + const struct attribute_group *groups[INA2XX_MAX_ATTRIBUTE_GROUPS];
> u16 regs[INA2XX_MAX_REGISTERS];
> };
>
> @@ -115,6 +126,38 @@ static const struct ina2xx_config ina2xx_config[] = {
> },
> };
>
> +/*
> + * Available averaging rates for ina226. The indices correspond with
> + * the bit values expected by the chip (according to the ina226 datasheet,
> + * table 3 AVG bit settings, found at
> + * http://www.ti.com/lit/ds/symlink/ina226.pdf.
> + */
> +static const int ina226_avg_tab[] = { 1, 4, 16, 64, 128, 256, 512, 1024 };
> +
> +static int ina226_avg_bits(int avg)
> +{
> + int i;
> +
> + for (i = 0; i < ARRAY_SIZE(ina226_avg_tab); i++) {
> + if (avg == ina226_avg_tab[i])
> + return i;
I would suggest to select the closest valid average.
> + }
> +
> + return -EINVAL;
> +}
> +
> +static int ina226_avg_val(int bits)
> +{
> + /*
> + * Value read from the config register should be correct, but do check
> + * the boundary just in case.
> + */
> + if (bits >= ARRAY_SIZE(ina226_avg_tab))
> + return -ENODEV;
> +
> + return ina226_avg_tab[bits];
> +}
> +
> static int ina2xx_calibrate(struct ina2xx_data *data)
> {
> return i2c_smbus_write_word_swapped(data->client, INA2XX_CALIBRATION,
> @@ -131,7 +174,7 @@ static int ina2xx_init(struct ina2xx_data *data)
>
> /* device configuration */
> ret = i2c_smbus_write_word_swapped(client, INA2XX_CONFIG,
> - data->config->config_default);
> + data->curr_config);
> if (ret < 0)
> return ret;
>
> @@ -292,6 +335,66 @@ static ssize_t ina2xx_set_shunt(struct device *dev,
> return count;
> }
>
> +static ssize_t ina226_show_avg(struct device *dev,
> + struct device_attribute *da, char *buf)
> +{
> + struct ina2xx_data *data = ina2xx_update_device(dev);
> + int avg, i, written = 0;
> + const char *fmt;
> +
> + if (IS_ERR(data))
> + return PTR_ERR(data);
> +
> + avg = ina226_avg_val(INA226_READ_AVG(data->regs[INA2XX_CONFIG]));
> + if (avg < 0)
> + return avg;
> +
> + for (i = 0; i < ARRAY_SIZE(ina226_avg_tab); i++) {
> + if (avg == ina226_avg_tab[i])
> + fmt = "\t[%d]";
> + else
> + fmt = "\t%d";
> +
> + written += snprintf(buf + written, PAGE_SIZE - written,
> + fmt, ina226_avg_tab[i]);
> + }
> + written += snprintf(buf + written, PAGE_SIZE - written, "\n");
> +
No. sysfs attributes return a single value, not a range.
So you have to return the current value here and nothing else.
This is why it would be better to be more flexibe when accepting a new average.
> + return written;
> +}
> +
> +static ssize_t ina226_set_avg(struct device *dev,
> + struct device_attribute *da,
> + const char *buf, size_t count)
> +{
> + struct ina2xx_data *data = ina2xx_update_device(dev);
Calling update_device here is not necessary.
> + long val;
> + int status, avg;
> +
> + if (IS_ERR(data))
> + return PTR_ERR(data);
> +
> + status = kstrtol(buf, 10, &val);
> + if (status < 0)
> + return status;
> +
> + avg = ina226_avg_bits(val);
> + if (avg < 0)
> + return avg;
> +
> + mutex_lock(&data->update_lock);
> + data->curr_config = (data->regs[INA2XX_CONFIG] &
> + INA226_AVG_WR_MASK) | (avg << 9);
> + status = i2c_smbus_write_word_swapped(data->client,
> + INA2XX_CONFIG,
> + data->curr_config);
You should set data->valid to 0 here to ensure that the next access
re-reads all registers.
> + mutex_unlock(&data->update_lock);
> + if (status < 0)
> + return status;
> +
> + return count;
> +}
> +
> /* shunt voltage */
> static SENSOR_DEVICE_ATTR(in0_input, S_IRUGO, ina2xx_show_value, NULL,
> INA2XX_SHUNT_VOLTAGE);
> @@ -313,6 +416,10 @@ static SENSOR_DEVICE_ATTR(shunt_resistor, S_IRUGO | S_IWUSR,
> ina2xx_show_value, ina2xx_set_shunt,
> INA2XX_CALIBRATION);
>
> +/* averaging rate */
> +static SENSOR_DEVICE_ATTR(avg_rate, S_IRUGO | S_IWUSR,
> + ina226_show_avg, ina226_set_avg, 0);
> +
> /* pointers to created device attributes */
> static struct attribute *ina2xx_attrs[] = {
> &sensor_dev_attr_in0_input.dev_attr.attr,
> @@ -322,7 +429,19 @@ static struct attribute *ina2xx_attrs[] = {
> &sensor_dev_attr_shunt_resistor.dev_attr.attr,
> NULL,
> };
> -ATTRIBUTE_GROUPS(ina2xx);
> +
> +static const struct attribute_group ina2xx_group = {
> + .attrs = ina2xx_attrs,
> +};
> +
> +static struct attribute *ina226_attrs[] = {
> + &sensor_dev_attr_avg_rate.dev_attr.attr,
> + NULL,
> +};
> +
> +static const struct attribute_group ina226_group = {
> + .attrs = ina226_attrs,
> +};
>
> static int ina2xx_probe(struct i2c_client *client,
> const struct i2c_device_id *id)
> @@ -333,7 +452,7 @@ static int ina2xx_probe(struct i2c_client *client,
> struct ina2xx_data *data;
> struct device *hwmon_dev;
> u32 val;
> - int ret;
> + int ret, group = 0;
>
> if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_WORD_DATA))
> return -ENODEV;
> @@ -355,6 +474,7 @@ static int ina2xx_probe(struct i2c_client *client,
> /* set the device type */
> data->kind = id->driver_data;
> data->config = &ina2xx_config[data->kind];
> + data->curr_config = data->config->config_default;
> data->client = client;
>
> if (data->rshunt <= 0 ||
> @@ -369,8 +489,12 @@ static int ina2xx_probe(struct i2c_client *client,
>
> mutex_init(&data->update_lock);
>
> + data->groups[group++] = &ina2xx_group;
> + if (data->kind == ina226)
> + data->groups[group++] = &ina226_group;
> +
> hwmon_dev = devm_hwmon_device_register_with_groups(dev, client->name,
> - data, ina2xx_groups);
> + data, data->groups);
> if (IS_ERR(hwmon_dev))
> return PTR_ERR(hwmon_dev);
>
^ permalink raw reply [flat|nested] 8+ messages in thread
end of thread, other threads:[~2014-12-21 16:36 UTC | newest]
Thread overview: 8+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2014-12-13 16:27 [PATCH v7 0/5] hwmon: ina2xx: implement chip reinitialization and add new attributes Bartosz Golaszewski
2014-12-13 16:27 ` [PATCH v7 1/5] hwmon: ina2xx: reinitialize the chip in case it's been reset Bartosz Golaszewski
2014-12-13 16:27 ` [PATCH v7 2/5] hwmon: ina2xx: remove a stray new line Bartosz Golaszewski
2014-12-13 16:27 ` [PATCH v7 3/5] hwmon: ina2xx: don't accept shunt values greater than the calibration factor Bartosz Golaszewski
2014-12-13 16:27 ` [PATCH v7 4/5] hwmon: ina2xx: make shunt resistance configurable at run-time Bartosz Golaszewski
2014-12-13 16:27 ` [PATCH v7 5/5] hwmon: ina2xx: allow to change the averaging rate " Bartosz Golaszewski
2014-12-21 16:36 ` [v7, " Guenter Roeck
2014-12-20 3:23 ` [PATCH v7 0/5] hwmon: ina2xx: implement chip reinitialization and add new attributes Guenter Roeck
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