* [PATCH/RFC v7 0/3] LED / flash API integration - LED Flash Class
@ 2014-11-12 16:09 Jacek Anaszewski
2014-11-12 16:09 ` [PATCH/RFC v7 1/3] leds: Add support for setting brightness in a synchronous way Jacek Anaszewski
` (2 more replies)
0 siblings, 3 replies; 9+ messages in thread
From: Jacek Anaszewski @ 2014-11-12 16:09 UTC (permalink / raw)
To: linux-leds
Cc: linux-media, sakari.ailus, kyungmin.park, b.zolnierkie, Jacek Anaszewski
This patch set is the follow-up of the LED / flash API integration
series [1].
========================
Changes since version 6:
========================
- removed addition of public LED subsystem API for setting
torch brightness in favour of internal API for
synchronous and asynchronous led brightness level setting
- fixed possible race condition upon creating LED Flash class
related sysfs attributes
========================
Changes since version 5:
========================
- removed flash manager framework - its implementation needs
further thorough discussion.
- removed external strobe facilities from the LED Flash Class
and provided external_strobe_set op in v4l2-flash. LED subsystem
should be strobe provider agnostic.
Thanks,
Jacek Anaszewski
[1] https://lkml.org/lkml/2014/7/11/914
Jacek Anaszewski (3):
leds: Add support for setting brightness in a synchronous way
leds: Add LED Flash Class wrapper to LED subsystem
Documentation: leds: Add description of LED Flash Class extension
Documentation/leds/leds-class-flash.txt | 39 +++
drivers/leds/Kconfig | 11 +
drivers/leds/Makefile | 1 +
drivers/leds/led-class-flash.c | 511 +++++++++++++++++++++++++++++
drivers/leds/led-class.c | 14 +-
drivers/leds/led-core.c | 19 +-
drivers/leds/leds.h | 20 +-
drivers/leds/trigger/ledtrig-backlight.c | 8 +-
drivers/leds/trigger/ledtrig-default-on.c | 2 +-
drivers/leds/trigger/ledtrig-gpio.c | 6 +-
drivers/leds/trigger/ledtrig-heartbeat.c | 2 +-
drivers/leds/trigger/ledtrig-oneshot.c | 4 +-
drivers/leds/trigger/ledtrig-transient.c | 10 +-
include/linux/led-class-flash.h | 229 +++++++++++++
include/linux/leds.h | 11 +
15 files changed, 861 insertions(+), 26 deletions(-)
create mode 100644 Documentation/leds/leds-class-flash.txt
create mode 100644 drivers/leds/led-class-flash.c
create mode 100644 include/linux/led-class-flash.h
--
1.7.9.5
^ permalink raw reply [flat|nested] 9+ messages in thread
* [PATCH/RFC v7 1/3] leds: Add support for setting brightness in a synchronous way
2014-11-12 16:09 [PATCH/RFC v7 0/3] LED / flash API integration - LED Flash Class Jacek Anaszewski
@ 2014-11-12 16:09 ` Jacek Anaszewski
2014-11-13 18:43 ` Bryan Wu
2014-11-12 16:09 ` [PATCH/RFC v7 2/3] leds: Add LED Flash Class wrapper to LED subsystem Jacek Anaszewski
2014-11-12 16:09 ` [PATCH/RFC v7 3/3] Documentation: leds: Add description of LED Flash Class extension Jacek Anaszewski
2 siblings, 1 reply; 9+ messages in thread
From: Jacek Anaszewski @ 2014-11-12 16:09 UTC (permalink / raw)
To: linux-leds
Cc: linux-media, sakari.ailus, kyungmin.park, b.zolnierkie,
Jacek Anaszewski, Bryan Wu, Richard Purdie
There are use cases when setting a LED brightness has to
have immediate effect (e.g. setting a torch LED brightness).
This patch extends LED subsystem to support such operations.
The LED subsystem internal API __led_set_brightness is changed
to led_set_brightness_async and new led_set_brightness_sync API
is added.
Signed-off-by: Jacek Anaszewski <j.anaszewski@samsung.com>
Acked-by: Kyungmin Park <kyungmin.park@samsung.com>
Cc: Bryan Wu <cooloney@gmail.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
---
drivers/leds/led-class.c | 10 ++++++----
drivers/leds/led-core.c | 19 ++++++++++++++++---
drivers/leds/leds.h | 20 ++++++++++++++++----
drivers/leds/trigger/ledtrig-backlight.c | 8 ++++----
drivers/leds/trigger/ledtrig-default-on.c | 2 +-
drivers/leds/trigger/ledtrig-gpio.c | 6 +++---
drivers/leds/trigger/ledtrig-heartbeat.c | 2 +-
drivers/leds/trigger/ledtrig-oneshot.c | 4 ++--
drivers/leds/trigger/ledtrig-transient.c | 10 ++++++----
include/linux/leds.h | 8 ++++++++
10 files changed, 63 insertions(+), 26 deletions(-)
diff --git a/drivers/leds/led-class.c b/drivers/leds/led-class.c
index 65722de..dbeebac 100644
--- a/drivers/leds/led-class.c
+++ b/drivers/leds/led-class.c
@@ -55,7 +55,7 @@ static ssize_t brightness_store(struct device *dev,
if (state == LED_OFF)
led_trigger_remove(led_cdev);
- __led_set_brightness(led_cdev, state);
+ led_set_brightness(led_cdev, state);
ret = size;
unlock:
@@ -109,7 +109,7 @@ static void led_timer_function(unsigned long data)
unsigned long delay;
if (!led_cdev->blink_delay_on || !led_cdev->blink_delay_off) {
- __led_set_brightness(led_cdev, LED_OFF);
+ led_set_brightness_async(led_cdev, LED_OFF);
return;
}
@@ -132,7 +132,7 @@ static void led_timer_function(unsigned long data)
delay = led_cdev->blink_delay_off;
}
- __led_set_brightness(led_cdev, brightness);
+ led_set_brightness_async(led_cdev, brightness);
/* Return in next iteration if led is in one-shot mode and we are in
* the final blink state so that the led is toggled each delay_on +
@@ -158,7 +158,7 @@ static void set_brightness_delayed(struct work_struct *ws)
led_stop_software_blink(led_cdev);
- __led_set_brightness(led_cdev, led_cdev->delayed_set_value);
+ led_set_brightness_async(led_cdev, led_cdev->delayed_set_value);
}
/**
@@ -233,6 +233,8 @@ int led_classdev_register(struct device *parent, struct led_classdev *led_cdev)
if (!led_cdev->max_brightness)
led_cdev->max_brightness = LED_FULL;
+ led_cdev->flags |= SET_BRIGHTNESS_ASYNC;
+
led_update_brightness(led_cdev);
INIT_WORK(&led_cdev->set_brightness_work, set_brightness_delayed);
diff --git a/drivers/leds/led-core.c b/drivers/leds/led-core.c
index be6d9fa..a745e32 100644
--- a/drivers/leds/led-core.c
+++ b/drivers/leds/led-core.c
@@ -42,13 +42,13 @@ static void led_set_software_blink(struct led_classdev *led_cdev,
/* never on - just set to off */
if (!delay_on) {
- __led_set_brightness(led_cdev, LED_OFF);
+ led_set_brightness_async(led_cdev, LED_OFF);
return;
}
/* never off - just set to brightness */
if (!delay_off) {
- __led_set_brightness(led_cdev, led_cdev->blink_brightness);
+ led_set_brightness_async(led_cdev, led_cdev->blink_brightness);
return;
}
@@ -117,6 +117,8 @@ EXPORT_SYMBOL_GPL(led_stop_software_blink);
void led_set_brightness(struct led_classdev *led_cdev,
enum led_brightness brightness)
{
+ int ret = 0;
+
/* delay brightness setting if need to stop soft-blink timer */
if (led_cdev->blink_delay_on || led_cdev->blink_delay_off) {
led_cdev->delayed_set_value = brightness;
@@ -124,7 +126,18 @@ void led_set_brightness(struct led_classdev *led_cdev,
return;
}
- __led_set_brightness(led_cdev, brightness);
+ if (led_cdev->flags & SET_BRIGHTNESS_ASYNC) {
+ led_set_brightness_async(led_cdev, brightness);
+ return;
+ } else if (led_cdev->flags & SET_BRIGHTNESS_SYNC) {
+ ret = led_set_brightness_sync(led_cdev, brightness);
+ } else {
+ ret = -EINVAL;
+ }
+
+ if (ret < 0)
+ dev_dbg(led_cdev->dev, "Setting LED brightness failed (%d)\n",
+ ret);
}
EXPORT_SYMBOL(led_set_brightness);
diff --git a/drivers/leds/leds.h b/drivers/leds/leds.h
index 4c50365..2348dbd 100644
--- a/drivers/leds/leds.h
+++ b/drivers/leds/leds.h
@@ -17,16 +17,28 @@
#include <linux/rwsem.h>
#include <linux/leds.h>
-static inline void __led_set_brightness(struct led_classdev *led_cdev,
+static inline void led_set_brightness_async(struct led_classdev *led_cdev,
enum led_brightness value)
{
- if (value > led_cdev->max_brightness)
- value = led_cdev->max_brightness;
- led_cdev->brightness = value;
+ led_cdev->brightness = min(value, led_cdev->max_brightness);
+
if (!(led_cdev->flags & LED_SUSPENDED))
led_cdev->brightness_set(led_cdev, value);
}
+static inline int led_set_brightness_sync(struct led_classdev *led_cdev,
+ enum led_brightness value)
+{
+ int ret = 0;
+
+ led_cdev->brightness = min(value, led_cdev->max_brightness);
+
+ if (!(led_cdev->flags & LED_SUSPENDED))
+ ret = led_cdev->brightness_set_sync(led_cdev,
+ led_cdev->brightness);
+ return ret;
+}
+
static inline int led_get_brightness(struct led_classdev *led_cdev)
{
return led_cdev->brightness;
diff --git a/drivers/leds/trigger/ledtrig-backlight.c b/drivers/leds/trigger/ledtrig-backlight.c
index 47e55aa..59eca17 100644
--- a/drivers/leds/trigger/ledtrig-backlight.c
+++ b/drivers/leds/trigger/ledtrig-backlight.c
@@ -51,9 +51,9 @@ static int fb_notifier_callback(struct notifier_block *p,
if ((n->old_status == UNBLANK) ^ n->invert) {
n->brightness = led->brightness;
- __led_set_brightness(led, LED_OFF);
+ led_set_brightness_async(led, LED_OFF);
} else {
- __led_set_brightness(led, n->brightness);
+ led_set_brightness_async(led, n->brightness);
}
n->old_status = new_status;
@@ -89,9 +89,9 @@ static ssize_t bl_trig_invert_store(struct device *dev,
/* After inverting, we need to update the LED. */
if ((n->old_status == BLANK) ^ n->invert)
- __led_set_brightness(led, LED_OFF);
+ led_set_brightness_async(led, LED_OFF);
else
- __led_set_brightness(led, n->brightness);
+ led_set_brightness_async(led, n->brightness);
return num;
}
diff --git a/drivers/leds/trigger/ledtrig-default-on.c b/drivers/leds/trigger/ledtrig-default-on.c
index 81a91be..6f38f88 100644
--- a/drivers/leds/trigger/ledtrig-default-on.c
+++ b/drivers/leds/trigger/ledtrig-default-on.c
@@ -19,7 +19,7 @@
static void defon_trig_activate(struct led_classdev *led_cdev)
{
- __led_set_brightness(led_cdev, led_cdev->max_brightness);
+ led_set_brightness_async(led_cdev, led_cdev->max_brightness);
}
static struct led_trigger defon_led_trigger = {
diff --git a/drivers/leds/trigger/ledtrig-gpio.c b/drivers/leds/trigger/ledtrig-gpio.c
index c86c418..4cc7040 100644
--- a/drivers/leds/trigger/ledtrig-gpio.c
+++ b/drivers/leds/trigger/ledtrig-gpio.c
@@ -54,12 +54,12 @@ static void gpio_trig_work(struct work_struct *work)
if (tmp) {
if (gpio_data->desired_brightness)
- __led_set_brightness(gpio_data->led,
+ led_set_brightness_async(gpio_data->led,
gpio_data->desired_brightness);
else
- __led_set_brightness(gpio_data->led, LED_FULL);
+ led_set_brightness_async(gpio_data->led, LED_FULL);
} else {
- __led_set_brightness(gpio_data->led, LED_OFF);
+ led_set_brightness_async(gpio_data->led, LED_OFF);
}
}
diff --git a/drivers/leds/trigger/ledtrig-heartbeat.c b/drivers/leds/trigger/ledtrig-heartbeat.c
index 5c8464a..fea6871 100644
--- a/drivers/leds/trigger/ledtrig-heartbeat.c
+++ b/drivers/leds/trigger/ledtrig-heartbeat.c
@@ -74,7 +74,7 @@ static void led_heartbeat_function(unsigned long data)
break;
}
- __led_set_brightness(led_cdev, brightness);
+ led_set_brightness_async(led_cdev, brightness);
mod_timer(&heartbeat_data->timer, jiffies + delay);
}
diff --git a/drivers/leds/trigger/ledtrig-oneshot.c b/drivers/leds/trigger/ledtrig-oneshot.c
index cb4c746..fbd02cd 100644
--- a/drivers/leds/trigger/ledtrig-oneshot.c
+++ b/drivers/leds/trigger/ledtrig-oneshot.c
@@ -63,9 +63,9 @@ static ssize_t led_invert_store(struct device *dev,
oneshot_data->invert = !!state;
if (oneshot_data->invert)
- __led_set_brightness(led_cdev, LED_FULL);
+ led_set_brightness_async(led_cdev, LED_FULL);
else
- __led_set_brightness(led_cdev, LED_OFF);
+ led_set_brightness_async(led_cdev, LED_OFF);
return size;
}
diff --git a/drivers/leds/trigger/ledtrig-transient.c b/drivers/leds/trigger/ledtrig-transient.c
index e5abc00..3c34de4 100644
--- a/drivers/leds/trigger/ledtrig-transient.c
+++ b/drivers/leds/trigger/ledtrig-transient.c
@@ -41,7 +41,7 @@ static void transient_timer_function(unsigned long data)
struct transient_trig_data *transient_data = led_cdev->trigger_data;
transient_data->activate = 0;
- __led_set_brightness(led_cdev, transient_data->restore_state);
+ led_set_brightness_async(led_cdev, transient_data->restore_state);
}
static ssize_t transient_activate_show(struct device *dev,
@@ -72,7 +72,8 @@ static ssize_t transient_activate_store(struct device *dev,
if (state == 0 && transient_data->activate == 1) {
del_timer(&transient_data->timer);
transient_data->activate = state;
- __led_set_brightness(led_cdev, transient_data->restore_state);
+ led_set_brightness_async(led_cdev,
+ transient_data->restore_state);
return size;
}
@@ -80,7 +81,7 @@ static ssize_t transient_activate_store(struct device *dev,
if (state == 1 && transient_data->activate == 0 &&
transient_data->duration != 0) {
transient_data->activate = state;
- __led_set_brightness(led_cdev, transient_data->state);
+ led_set_brightness_async(led_cdev, transient_data->state);
transient_data->restore_state =
(transient_data->state == LED_FULL) ? LED_OFF : LED_FULL;
mod_timer(&transient_data->timer,
@@ -203,7 +204,8 @@ static void transient_trig_deactivate(struct led_classdev *led_cdev)
if (led_cdev->activated) {
del_timer_sync(&transient_data->timer);
- __led_set_brightness(led_cdev, transient_data->restore_state);
+ led_set_brightness_async(led_cdev,
+ transient_data->restore_state);
device_remove_file(led_cdev->dev, &dev_attr_activate);
device_remove_file(led_cdev->dev, &dev_attr_duration);
device_remove_file(led_cdev->dev, &dev_attr_state);
diff --git a/include/linux/leds.h b/include/linux/leds.h
index 3737a5a..cfceef3 100644
--- a/include/linux/leds.h
+++ b/include/linux/leds.h
@@ -44,11 +44,19 @@ struct led_classdev {
#define LED_BLINK_ONESHOT_STOP (1 << 18)
#define LED_BLINK_INVERT (1 << 19)
#define LED_SYSFS_DISABLE (1 << 20)
+#define SET_BRIGHTNESS_ASYNC (1 << 21)
+#define SET_BRIGHTNESS_SYNC (1 << 22)
/* Set LED brightness level */
/* Must not sleep, use a workqueue if needed */
void (*brightness_set)(struct led_classdev *led_cdev,
enum led_brightness brightness);
+ /*
+ * Set LED brightness level immediately - it can block the caller for
+ * the time required for accessing a LED device register.
+ */
+ int (*brightness_set_sync)(struct led_classdev *led_cdev,
+ enum led_brightness brightness);
/* Get LED brightness level */
enum led_brightness (*brightness_get)(struct led_classdev *led_cdev);
--
1.7.9.5
^ permalink raw reply related [flat|nested] 9+ messages in thread
* [PATCH/RFC v7 2/3] leds: Add LED Flash Class wrapper to LED subsystem
2014-11-12 16:09 [PATCH/RFC v7 0/3] LED / flash API integration - LED Flash Class Jacek Anaszewski
2014-11-12 16:09 ` [PATCH/RFC v7 1/3] leds: Add support for setting brightness in a synchronous way Jacek Anaszewski
@ 2014-11-12 16:09 ` Jacek Anaszewski
2014-11-27 8:43 ` Sakari Ailus
2014-11-12 16:09 ` [PATCH/RFC v7 3/3] Documentation: leds: Add description of LED Flash Class extension Jacek Anaszewski
2 siblings, 1 reply; 9+ messages in thread
From: Jacek Anaszewski @ 2014-11-12 16:09 UTC (permalink / raw)
To: linux-leds
Cc: linux-media, sakari.ailus, kyungmin.park, b.zolnierkie,
Jacek Anaszewski, Bryan Wu, Richard Purdie
Some LED devices support two operation modes - torch and flash.
This patch provides support for flash LED devices in the LED subsystem
by introducing new sysfs attributes and kernel internal interface.
The attributes being introduced are: flash_brightness, flash_strobe,
flash_timeout, max_flash_timeout, max_flash_brightness, flash_fault,
indicator_brightness and max_indicator_brightness. All the flash
related features are placed in a separate module.
The modifications aim to be compatible with V4L2 framework requirements
related to the flash devices management. The design assumes that V4L2
sub-device can take of the LED class device control and communicate
with it through the kernel internal interface. When V4L2 Flash sub-device
file is opened, the LED class device sysfs interface is made
unavailable.
Signed-off-by: Jacek Anaszewski <j.anaszewski@samsung.com>
Acked-by: Kyungmin Park <kyungmin.park@samsung.com>
Cc: Bryan Wu <cooloney@gmail.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
---
drivers/leds/Kconfig | 11 +
drivers/leds/Makefile | 1 +
drivers/leds/led-class-flash.c | 511 +++++++++++++++++++++++++++++++++++++++
drivers/leds/led-class.c | 4 +
include/linux/led-class-flash.h | 229 ++++++++++++++++++
include/linux/leds.h | 3 +
6 files changed, 759 insertions(+)
create mode 100644 drivers/leds/led-class-flash.c
create mode 100644 include/linux/led-class-flash.h
diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig
index 808095b..50c4370 100644
--- a/drivers/leds/Kconfig
+++ b/drivers/leds/Kconfig
@@ -19,6 +19,17 @@ config LEDS_CLASS
This option enables the led sysfs class in /sys/class/leds. You'll
need this to do anything useful with LEDs. If unsure, say N.
+config LEDS_CLASS_FLASH
+ tristate "LED Flash Class Support"
+ depends on LEDS_CLASS
+ depends on OF
+ help
+ This option enables the flash led sysfs class in /sys/class/leds.
+ It wrapps LED Class and adds flash LEDs specific sysfs attributes
+ and kernel internal API to it. You'll need this to provide support
+ for the flash related features of a LED device. It can be built
+ as a module.
+
comment "LED drivers"
config LEDS_88PM860X
diff --git a/drivers/leds/Makefile b/drivers/leds/Makefile
index a2b1647..73c0cec 100644
--- a/drivers/leds/Makefile
+++ b/drivers/leds/Makefile
@@ -2,6 +2,7 @@
# LED Core
obj-$(CONFIG_NEW_LEDS) += led-core.o
obj-$(CONFIG_LEDS_CLASS) += led-class.o
+obj-$(CONFIG_LEDS_CLASS_FLASH) += led-class-flash.o
obj-$(CONFIG_LEDS_TRIGGERS) += led-triggers.o
# LED Platform Drivers
diff --git a/drivers/leds/led-class-flash.c b/drivers/leds/led-class-flash.c
new file mode 100644
index 0000000..bec99f6
--- /dev/null
+++ b/drivers/leds/led-class-flash.c
@@ -0,0 +1,511 @@
+/*
+ * LED Flash Class interface
+ *
+ * Copyright (C) 2014 Samsung Electronics Co., Ltd.
+ * Author: Jacek Anaszewski <j.anaszewski@samsung.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/device.h>
+#include <linux/init.h>
+#include <linux/leds.h>
+#include <linux/led-class-flash.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include "leds.h"
+
+#define has_flash_op(flash, op) \
+ (flash && flash->ops->op)
+
+#define call_flash_op(flash, op, args...) \
+ ((has_flash_op(flash, op)) ? \
+ (flash->ops->op(flash, args)) : \
+ -EINVAL)
+
+static ssize_t flash_brightness_store(struct device *dev,
+ struct device_attribute *attr, const char *buf, size_t size)
+{
+ struct led_classdev *led_cdev = dev_get_drvdata(dev);
+ struct led_classdev_flash *flash = lcdev_to_flash(led_cdev);
+ unsigned long state;
+ ssize_t ret;
+
+ mutex_lock(&led_cdev->led_access);
+
+ if (led_sysfs_is_disabled(led_cdev)) {
+ ret = -EBUSY;
+ goto unlock;
+ }
+
+ ret = kstrtoul(buf, 10, &state);
+ if (ret)
+ goto unlock;
+
+ ret = led_set_flash_brightness(flash, state);
+ if (ret < 0)
+ goto unlock;
+
+ ret = size;
+unlock:
+ mutex_unlock(&led_cdev->led_access);
+ return ret;
+}
+
+static ssize_t flash_brightness_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct led_classdev *led_cdev = dev_get_drvdata(dev);
+ struct led_classdev_flash *flash = lcdev_to_flash(led_cdev);
+
+ /* no lock needed for this */
+ led_update_flash_brightness(flash);
+
+ return sprintf(buf, "%u\n", flash->brightness.val);
+}
+static DEVICE_ATTR_RW(flash_brightness);
+
+static ssize_t max_flash_brightness_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct led_classdev *led_cdev = dev_get_drvdata(dev);
+ struct led_classdev_flash *flash = lcdev_to_flash(led_cdev);
+
+ return sprintf(buf, "%u\n", flash->brightness.max);
+}
+static DEVICE_ATTR_RO(max_flash_brightness);
+
+static ssize_t indicator_brightness_store(struct device *dev,
+ struct device_attribute *attr, const char *buf, size_t size)
+{
+ struct led_classdev *led_cdev = dev_get_drvdata(dev);
+ struct led_classdev_flash *flash = lcdev_to_flash(led_cdev);
+ unsigned long state;
+ ssize_t ret;
+
+ mutex_lock(&led_cdev->led_access);
+
+ if (led_sysfs_is_disabled(led_cdev)) {
+ ret = -EBUSY;
+ goto unlock;
+ }
+
+ ret = kstrtoul(buf, 10, &state);
+ if (ret)
+ goto unlock;
+
+ ret = led_set_indicator_brightness(flash, state);
+ if (ret < 0)
+ goto unlock;
+
+ ret = size;
+unlock:
+ mutex_unlock(&led_cdev->led_access);
+ return ret;
+}
+
+static ssize_t indicator_brightness_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct led_classdev *led_cdev = dev_get_drvdata(dev);
+ struct led_classdev_flash *flash = lcdev_to_flash(led_cdev);
+
+ /* no lock needed for this */
+ led_update_indicator_brightness(flash);
+
+ return sprintf(buf, "%u\n", flash->indicator_brightness->val);
+}
+static DEVICE_ATTR_RW(indicator_brightness);
+
+static ssize_t max_indicator_brightness_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct led_classdev *led_cdev = dev_get_drvdata(dev);
+ struct led_classdev_flash *flash = lcdev_to_flash(led_cdev);
+
+ return sprintf(buf, "%u\n", flash->indicator_brightness->max);
+}
+static DEVICE_ATTR_RO(max_indicator_brightness);
+
+static ssize_t flash_strobe_store(struct device *dev,
+ struct device_attribute *attr, const char *buf, size_t size)
+{
+ struct led_classdev *led_cdev = dev_get_drvdata(dev);
+ struct led_classdev_flash *flash = lcdev_to_flash(led_cdev);
+ unsigned long state;
+ ssize_t ret = -EINVAL;
+
+ mutex_lock(&led_cdev->led_access);
+
+ if (led_sysfs_is_disabled(led_cdev)) {
+ ret = -EBUSY;
+ goto unlock;
+ }
+
+ ret = kstrtoul(buf, 10, &state);
+ if (ret)
+ goto unlock;
+
+ if (state < 0 || state > 1) {
+ ret = -EINVAL;
+ goto unlock;
+ }
+
+ ret = led_set_flash_strobe(flash, state);
+ if (ret < 0)
+ goto unlock;
+ ret = size;
+unlock:
+ mutex_unlock(&led_cdev->led_access);
+ return ret;
+}
+
+static ssize_t flash_strobe_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct led_classdev *led_cdev = dev_get_drvdata(dev);
+ struct led_classdev_flash *flash = lcdev_to_flash(led_cdev);
+ bool state;
+ int ret;
+
+ /* no lock needed for this */
+ ret = led_get_flash_strobe(flash, &state);
+ if (ret < 0)
+ return ret;
+
+ return sprintf(buf, "%u\n", state);
+}
+static DEVICE_ATTR_RW(flash_strobe);
+
+static ssize_t flash_timeout_store(struct device *dev,
+ struct device_attribute *attr, const char *buf, size_t size)
+{
+ struct led_classdev *led_cdev = dev_get_drvdata(dev);
+ struct led_classdev_flash *flash = lcdev_to_flash(led_cdev);
+ unsigned long flash_timeout;
+ ssize_t ret;
+
+ mutex_lock(&led_cdev->led_access);
+
+ if (led_sysfs_is_disabled(led_cdev)) {
+ ret = -EBUSY;
+ goto unlock;
+ }
+
+ ret = kstrtoul(buf, 10, &flash_timeout);
+ if (ret)
+ goto unlock;
+
+ ret = led_set_flash_timeout(flash, flash_timeout);
+ if (ret < 0)
+ goto unlock;
+
+ ret = size;
+unlock:
+ mutex_unlock(&led_cdev->led_access);
+ return ret;
+}
+
+static ssize_t flash_timeout_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct led_classdev *led_cdev = dev_get_drvdata(dev);
+ struct led_classdev_flash *flash = lcdev_to_flash(led_cdev);
+
+ return sprintf(buf, "%u\n", flash->timeout.val);
+}
+static DEVICE_ATTR_RW(flash_timeout);
+
+static ssize_t max_flash_timeout_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct led_classdev *led_cdev = dev_get_drvdata(dev);
+ struct led_classdev_flash *flash = lcdev_to_flash(led_cdev);
+
+ return sprintf(buf, "%u\n", flash->timeout.max);
+}
+static DEVICE_ATTR_RO(max_flash_timeout);
+
+static ssize_t flash_fault_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct led_classdev *led_cdev = dev_get_drvdata(dev);
+ struct led_classdev_flash *flash = lcdev_to_flash(led_cdev);
+ u32 fault;
+ int ret;
+
+ ret = led_get_flash_fault(flash, &fault);
+ if (ret < 0)
+ return -EINVAL;
+
+ return sprintf(buf, "0x%8.8x\n", fault);
+}
+static DEVICE_ATTR_RO(flash_fault);
+
+static struct attribute *led_flash_strobe_attrs[] = {
+ &dev_attr_flash_strobe.attr,
+ NULL,
+};
+
+static struct attribute *led_flash_indicator_attrs[] = {
+ &dev_attr_indicator_brightness.attr,
+ &dev_attr_max_indicator_brightness.attr,
+ NULL,
+};
+
+static struct attribute *led_flash_timeout_attrs[] = {
+ &dev_attr_flash_timeout.attr,
+ &dev_attr_max_flash_timeout.attr,
+ NULL,
+};
+
+static struct attribute *led_flash_brightness_attrs[] = {
+ &dev_attr_flash_brightness.attr,
+ &dev_attr_max_flash_brightness.attr,
+ NULL,
+};
+
+static struct attribute *led_flash_fault_attrs[] = {
+ &dev_attr_flash_fault.attr,
+ NULL,
+};
+
+static const struct attribute_group led_flash_strobe_group = {
+ .attrs = led_flash_strobe_attrs,
+};
+
+static const struct attribute_group led_flash_indicator_group = {
+ .attrs = led_flash_indicator_attrs,
+};
+
+static const struct attribute_group led_flash_timeout_group = {
+ .attrs = led_flash_timeout_attrs,
+};
+
+static const struct attribute_group led_flash_brightness_group = {
+ .attrs = led_flash_brightness_attrs,
+};
+
+static const struct attribute_group led_flash_fault_group = {
+ .attrs = led_flash_fault_attrs,
+};
+
+static const struct attribute_group *flash_groups[] = {
+ &led_flash_strobe_group,
+ NULL,
+ NULL,
+ NULL,
+ NULL,
+ NULL,
+};
+
+static void led_flash_resume(struct led_classdev *led_cdev)
+{
+ struct led_classdev_flash *flash = lcdev_to_flash(led_cdev);
+
+ call_flash_op(flash, flash_brightness_set, flash->brightness.val);
+ call_flash_op(flash, timeout_set, flash->timeout.val);
+ call_flash_op(flash, indicator_brightness_set,
+ flash->indicator_brightness->val);
+}
+
+static void led_flash_init_sysfs_groups(struct led_classdev_flash *flash)
+{
+ struct led_classdev *led_cdev = &flash->led_cdev;
+ const struct led_flash_ops *ops = flash->ops;
+ int num_sysfs_groups = 1;
+
+ if (led_cdev->flags & LED_DEV_CAP_INDICATOR)
+ flash_groups[num_sysfs_groups++] = &led_flash_indicator_group;
+
+ if (ops->flash_brightness_set)
+ flash_groups[num_sysfs_groups++] = &led_flash_brightness_group;
+
+ if (ops->timeout_set)
+ flash_groups[num_sysfs_groups++] = &led_flash_timeout_group;
+
+ if (ops->fault_get)
+ flash_groups[num_sysfs_groups++] = &led_flash_fault_group;
+
+ led_cdev->groups = flash_groups;
+}
+
+int led_classdev_flash_register(struct device *parent,
+ struct led_classdev_flash *flash)
+{
+ struct led_classdev *led_cdev;
+ const struct led_flash_ops *ops;
+ int ret;
+
+ if (!flash)
+ return -EINVAL;
+
+ led_cdev = &flash->led_cdev;
+
+ if (led_cdev->flags & LED_DEV_CAP_FLASH) {
+ if (!led_cdev->brightness_set_sync)
+ return -EINVAL;
+
+ ops = flash->ops;
+ if (!ops || !ops->strobe_set)
+ return -EINVAL;
+
+ if ((led_cdev->flags & LED_DEV_CAP_INDICATOR) &&
+ (!flash->indicator_brightness ||
+ !ops->indicator_brightness_set))
+ return -EINVAL;
+
+ led_cdev->flash_resume = led_flash_resume;
+ }
+
+ /* Select the sysfs attributes to be created for the device */
+ led_flash_init_sysfs_groups(flash);
+
+ /* Register led class device */
+ ret = led_classdev_register(parent, led_cdev);
+ if (ret < 0)
+ return ret;
+
+ /* Setting a torch brightness needs to have immediate effect */
+ led_cdev->flags &= ~SET_BRIGHTNESS_ASYNC;
+ led_cdev->flags |= SET_BRIGHTNESS_SYNC;
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(led_classdev_flash_register);
+
+void led_classdev_flash_unregister(struct led_classdev_flash *flash)
+{
+ if (!flash)
+ return;
+
+ led_classdev_unregister(&flash->led_cdev);
+}
+EXPORT_SYMBOL_GPL(led_classdev_flash_unregister);
+
+int led_set_flash_strobe(struct led_classdev_flash *flash, bool state)
+{
+ return call_flash_op(flash, strobe_set, state);
+}
+EXPORT_SYMBOL_GPL(led_set_flash_strobe);
+
+int led_get_flash_strobe(struct led_classdev_flash *flash, bool *state)
+{
+ return call_flash_op(flash, strobe_get, state);
+}
+EXPORT_SYMBOL_GPL(led_get_flash_strobe);
+
+static void led_clamp_align(struct led_flash_setting *s)
+{
+ u32 v, offset;
+
+ v = s->val + s->step / 2;
+ v = clamp(v, s->min, s->max);
+ offset = v - s->min;
+ offset = s->step * (offset / s->step);
+ s->val = s->min + offset;
+}
+
+int led_set_flash_timeout(struct led_classdev_flash *flash, u32 timeout)
+{
+ struct led_classdev *led_cdev = &flash->led_cdev;
+ struct led_flash_setting *s = &flash->timeout;
+ int ret = 0;
+
+ s->val = timeout;
+ led_clamp_align(s);
+
+ if (!(led_cdev->flags & LED_SUSPENDED))
+ ret = call_flash_op(flash, timeout_set, s->val);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(led_set_flash_timeout);
+
+int led_get_flash_fault(struct led_classdev_flash *flash, u32 *fault)
+{
+ return call_flash_op(flash, fault_get, fault);
+}
+EXPORT_SYMBOL_GPL(led_get_flash_fault);
+
+int led_set_flash_brightness(struct led_classdev_flash *flash,
+ u32 brightness)
+{
+ struct led_classdev *led_cdev = &flash->led_cdev;
+ struct led_flash_setting *s = &flash->brightness;
+ int ret = 0;
+
+ s->val = brightness;
+ led_clamp_align(s);
+
+ if (!(led_cdev->flags & LED_SUSPENDED))
+ ret = call_flash_op(flash, flash_brightness_set, s->val);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(led_set_flash_brightness);
+
+int led_update_flash_brightness(struct led_classdev_flash *flash)
+{
+ struct led_flash_setting *s = &flash->brightness;
+ u32 brightness;
+ int ret = 0;
+
+ if (has_flash_op(flash, flash_brightness_get)) {
+ ret = call_flash_op(flash, flash_brightness_get,
+ &brightness);
+ if (ret < 0)
+ return ret;
+ s->val = brightness;
+ }
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(led_update_flash_brightness);
+
+int led_set_indicator_brightness(struct led_classdev_flash *flash,
+ u32 brightness)
+{
+ struct led_classdev *led_cdev = &flash->led_cdev;
+ struct led_flash_setting *s = flash->indicator_brightness;
+ int ret = 0;
+
+ if (!s)
+ return -EINVAL;
+
+ s->val = brightness;
+ led_clamp_align(s);
+
+ if (!(led_cdev->flags & LED_SUSPENDED))
+ ret = call_flash_op(flash, indicator_brightness_set, s->val);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(led_set_indicator_brightness);
+
+int led_update_indicator_brightness(struct led_classdev_flash *flash)
+{
+ struct led_flash_setting *s = flash->indicator_brightness;
+ u32 brightness;
+ int ret = 0;
+
+ if (!s)
+ return -EINVAL;
+
+ if (has_flash_op(flash, indicator_brightness_get)) {
+ ret = call_flash_op(flash, indicator_brightness_get,
+ &brightness);
+ if (ret < 0)
+ return ret;
+ s->val = brightness;
+ }
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(led_update_indicator_brightness);
+
+MODULE_AUTHOR("Jacek Anaszewski <j.anaszewski@samsung.com>");
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("LED Flash Class Interface");
diff --git a/drivers/leds/led-class.c b/drivers/leds/led-class.c
index dbeebac..02564c5 100644
--- a/drivers/leds/led-class.c
+++ b/drivers/leds/led-class.c
@@ -179,6 +179,10 @@ EXPORT_SYMBOL_GPL(led_classdev_suspend);
void led_classdev_resume(struct led_classdev *led_cdev)
{
led_cdev->brightness_set(led_cdev, led_cdev->brightness);
+
+ if (led_cdev->flash_resume)
+ led_cdev->flash_resume(led_cdev);
+
led_cdev->flags &= ~LED_SUSPENDED;
}
EXPORT_SYMBOL_GPL(led_classdev_resume);
diff --git a/include/linux/led-class-flash.h b/include/linux/led-class-flash.h
new file mode 100644
index 0000000..df95b8a
--- /dev/null
+++ b/include/linux/led-class-flash.h
@@ -0,0 +1,229 @@
+/*
+ * LED Flash Class interface
+ *
+ * Copyright (C) 2014 Samsung Electronics Co., Ltd.
+ * Author: Jacek Anaszewski <j.anaszewski@samsung.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ */
+#ifndef __LINUX_FLASH_LEDS_H_INCLUDED
+#define __LINUX_FLASH_LEDS_H_INCLUDED
+
+#include <linux/leds.h>
+
+struct led_classdev_flash;
+struct device_node;
+
+/*
+ * Supported led fault bits - must be kept in synch
+ * with V4L2_FLASH_FAULT bits.
+ */
+#define LED_FAULT_OVER_VOLTAGE V4L2_FLASH_FAULT_OVER_VOLTAGE
+#define LED_FAULT_TIMEOUT V4L2_FLASH_FAULT_TIMEOUT
+#define LED_FAULT_OVER_TEMPERATURE V4L2_FLASH_FAULT_OVER_TEMPERATURE
+#define LED_FAULT_SHORT_CIRCUIT V4L2_FLASH_FAULT_SHORT_CIRCUIT
+#define LED_FAULT_OVER_CURRENT V4L2_FLASH_FAULT_OVER_CURRENT
+#define LED_FAULT_INDICATOR V4L2_FLASH_FAULT_INDICATOR
+#define LED_FAULT_UNDER_VOLTAGE V4L2_FLASH_FAULT_UNDER_VOLTAGE
+#define LED_FAULT_INPUT_VOLTAGE V4L2_FLASH_FAULT_INPUT_VOLTAGE
+#define LED_FAULT_LED_OVER_TEMPERATURE V4L2_FLASH_OVER_TEMPERATURE
+
+struct led_flash_ops {
+ /* set flash brightness */
+ int (*flash_brightness_set)(struct led_classdev_flash *flash,
+ u32 brightness);
+ /* get flash brightness */
+ int (*flash_brightness_get)(struct led_classdev_flash *flash,
+ u32 *brightness);
+ /* set flash indicator brightness */
+ int (*indicator_brightness_set)(struct led_classdev_flash *flash,
+ u32 brightness);
+ /* get flash indicator brightness */
+ int (*indicator_brightness_get)(struct led_classdev_flash *flash,
+ u32 *brightness);
+ /* set flash strobe state */
+ int (*strobe_set)(struct led_classdev_flash *flash, bool state);
+ /* get flash strobe state */
+ int (*strobe_get)(struct led_classdev_flash *flash, bool *state);
+ /* set flash timeout */
+ int (*timeout_set)(struct led_classdev_flash *flash, u32 timeout);
+ /* get the flash LED fault */
+ int (*fault_get)(struct led_classdev_flash *flash, u32 *fault);
+};
+
+/*
+ * Current value of a flash setting along
+ * with its constraints.
+ */
+struct led_flash_setting {
+ /* maximum allowed value */
+ u32 min;
+ /* maximum allowed value */
+ u32 max;
+ /* step value */
+ u32 step;
+ /* current value */
+ u32 val;
+};
+
+/*
+ * Aggregated flash settings - designed for ease
+ * of passing initialization data to the clients
+ * wrapping a LED Flash class device.
+ */
+struct led_flash_config {
+ struct led_flash_setting torch_brightness;
+ struct led_flash_setting flash_brightness;
+ struct led_flash_setting indicator_brightness;
+ struct led_flash_setting flash_timeout;
+ u32 flash_faults;
+};
+
+struct led_classdev_flash {
+ /* led class device */
+ struct led_classdev led_cdev;
+
+ /* flash led specific ops */
+ const struct led_flash_ops *ops;
+
+ /* flash brightness value in microamperes along with its constraints */
+ struct led_flash_setting brightness;
+
+ /* timeout value in microseconds along with its constraints */
+ struct led_flash_setting timeout;
+
+ /*
+ * Indicator brightness value in microamperes along with
+ * its constraints - this is an optional setting and must
+ * be allocated by the driver if the device supports privacy
+ * indicator led.
+ */
+ struct led_flash_setting *indicator_brightness;
+};
+
+static inline struct led_classdev_flash *lcdev_to_flash(
+ struct led_classdev *lcdev)
+{
+ return container_of(lcdev, struct led_classdev_flash, led_cdev);
+}
+
+/**
+ * led_classdev_flash_register - register a new object of led_classdev class
+ with support for flash LEDs
+ * @parent: the flash LED to register
+ * @flash: the led_classdev_flash structure for this device
+ *
+ * Returns: 0 on success or negative error value on failure
+ */
+int led_classdev_flash_register(struct device *parent,
+ struct led_classdev_flash *flash);
+
+/**
+ * led_classdev_flash_unregister - unregisters an object of led_classdev class
+ with support for flash LEDs
+ * @flash: the flash LED to unregister
+ *
+ * Unregister a previously registered via led_classdev_flash_register object
+ */
+void led_classdev_flash_unregister(struct led_classdev_flash *flash);
+
+/**
+ * led_set_flash_strobe - setup flash strobe
+ * @flash: the flash LED to set strobe on
+ * @state: 1 - strobe flash, 0 - stop flash strobe
+ *
+ * Strobe the flash LED.
+ *
+ * Returns: 0 on success or negative error value on failure
+ */
+extern int led_set_flash_strobe(struct led_classdev_flash *flash,
+ bool state);
+
+/**
+ * led_get_flash_strobe - get flash strobe status
+ * @flash: the flash LED to query
+ * @state: 1 - flash is strobing, 0 - flash is off
+ *
+ * Check whether the flash is strobing at the moment.
+ *
+u* Returns: 0 on success or negative error value on failure
+ */
+extern int led_get_flash_strobe(struct led_classdev_flash *flash,
+ bool *state);
+/**
+ * led_set_flash_brightness - set flash LED brightness
+ * @flash: the flash LED to set
+ * @brightness: the brightness to set it to
+ *
+ * Set a flash LED's brightness.
+ *
+ * Returns: 0 on success or negative error value on failure
+ */
+extern int led_set_flash_brightness(struct led_classdev_flash *flash,
+ u32 brightness);
+
+/**
+ * led_update_flash_brightness - update flash LED brightness
+ * @flash: the flash LED to query
+ *
+ * Get a flash LED's current brightness and update led_flash->brightness
+ * member with the obtained value.
+ *
+ * Returns: 0 on success or negative error value on failure
+ */
+extern int led_update_flash_brightness(struct led_classdev_flash *flash);
+
+/**
+ * led_set_flash_timeout - set flash LED timeout
+ * @flash: the flash LED to set
+ * @timeout: the flash timeout to set it to
+ *
+ * Set the flash strobe duration. The duration set by the driver
+ * is returned in the timeout argument and may differ from the
+ * one that was originally passed.
+ *
+ * Returns: 0 on success or negative error value on failure
+ */
+extern int led_set_flash_timeout(struct led_classdev_flash *flash,
+ u32 timeout);
+
+/**
+ * led_get_flash_fault - get the flash LED fault
+ * @flash: the flash LED to query
+ * @fault: bitmask containing flash faults
+ *
+ * Get the flash LED fault.
+ *
+ * Returns: 0 on success or negative error value on failure
+ */
+extern int led_get_flash_fault(struct led_classdev_flash *flash,
+ u32 *fault);
+
+/**
+ * led_set_indicator_brightness - set indicator LED brightness
+ * @flash: the flash LED to set
+ * @brightness: the brightness to set it to
+ *
+ * Set an indicator LED's brightness.
+ *
+ * Returns: 0 on success or negative error value on failure
+ */
+extern int led_set_indicator_brightness(struct led_classdev_flash *flash,
+ u32 led_brightness);
+
+/**
+ * led_update_indicator_brightness - update flash indicator LED brightness
+ * @flash: the flash LED to query
+ *
+ * Get a flash indicator LED's current brightness and update
+ * led_flash->indicator_brightness member with the obtained value.
+ *
+ * Returns: 0 on success or negative error value on failure
+ */
+extern int led_update_indicator_brightness(struct led_classdev_flash *flash);
+
+
+#endif /* __LINUX_FLASH_LEDS_H_INCLUDED */
diff --git a/include/linux/leds.h b/include/linux/leds.h
index cfceef3..b9a2797 100644
--- a/include/linux/leds.h
+++ b/include/linux/leds.h
@@ -46,6 +46,8 @@ struct led_classdev {
#define LED_SYSFS_DISABLE (1 << 20)
#define SET_BRIGHTNESS_ASYNC (1 << 21)
#define SET_BRIGHTNESS_SYNC (1 << 22)
+#define LED_DEV_CAP_FLASH (1 << 23)
+#define LED_DEV_CAP_INDICATOR (1 << 24)
/* Set LED brightness level */
/* Must not sleep, use a workqueue if needed */
@@ -81,6 +83,7 @@ struct led_classdev {
unsigned long blink_delay_on, blink_delay_off;
struct timer_list blink_timer;
int blink_brightness;
+ void (*flash_resume)(struct led_classdev *led_cdev);
struct work_struct set_brightness_work;
int delayed_set_value;
--
1.7.9.5
^ permalink raw reply related [flat|nested] 9+ messages in thread
* [PATCH/RFC v7 3/3] Documentation: leds: Add description of LED Flash Class extension
2014-11-12 16:09 [PATCH/RFC v7 0/3] LED / flash API integration - LED Flash Class Jacek Anaszewski
2014-11-12 16:09 ` [PATCH/RFC v7 1/3] leds: Add support for setting brightness in a synchronous way Jacek Anaszewski
2014-11-12 16:09 ` [PATCH/RFC v7 2/3] leds: Add LED Flash Class wrapper to LED subsystem Jacek Anaszewski
@ 2014-11-12 16:09 ` Jacek Anaszewski
2014-11-13 18:58 ` Bryan Wu
2 siblings, 1 reply; 9+ messages in thread
From: Jacek Anaszewski @ 2014-11-12 16:09 UTC (permalink / raw)
To: linux-leds
Cc: linux-media, sakari.ailus, kyungmin.park, b.zolnierkie,
Jacek Anaszewski, Bryan Wu, Richard Purdie
The documentation being added contains overall description of the
LED Flash Class and the related sysfs attributes.
Signed-off-by: Jacek Anaszewski <j.anaszewski@samsung.com>
Acked-by: Kyungmin Park <kyungmin.park@samsung.com>
Cc: Bryan Wu <cooloney@gmail.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
---
Documentation/leds/leds-class-flash.txt | 39 +++++++++++++++++++++++++++++++
1 file changed, 39 insertions(+)
create mode 100644 Documentation/leds/leds-class-flash.txt
diff --git a/Documentation/leds/leds-class-flash.txt b/Documentation/leds/leds-class-flash.txt
new file mode 100644
index 0000000..0164329
--- /dev/null
+++ b/Documentation/leds/leds-class-flash.txt
@@ -0,0 +1,39 @@
+
+Flash LED handling under Linux
+==============================
+
+Some LED devices support two modes - torch and flash. In order to enable
+support for flash LEDs CONFIG_LEDS_CLASS_FLASH symbol must be defined
+in the kernel config. A flash LED driver must register in the LED subsystem
+with led_classdev_flash_register to gain flash capabilities.
+
+Following sysfs attributes are exposed for controlling flash led devices:
+
+ - flash_brightness - flash LED brightness in microamperes (RW)
+ - max_flash_brightness - maximum available flash LED brightness (RO)
+ - indicator_brightness - privacy LED brightness in microamperes (RW)
+ - max_indicator_brightness - maximum privacy LED brightness in
+ microamperes (RO)
+ - flash_timeout - flash strobe duration in microseconds (RW)
+ - max_flash_timeout - maximum available flash strobe duration (RO)
+ - flash_strobe - flash strobe state (RW)
+ - flash_fault - bitmask of flash faults that may have occurred,
+ possible flags are:
+ * 0x01 - flash controller voltage to the flash LED has exceeded
+ the limit specific to the flash controller
+ * 0x02 - the flash strobe was still on when the timeout set by
+ the user has expired; not all flash controllers may
+ set this in all such conditions
+ * 0x04 - the flash controller has overheated
+ * 0x08 - the short circuit protection of the flash controller
+ has been triggered
+ * 0x10 - current in the LED power supply has exceeded the limit
+ specific to the flash controller
+ * 0x40 - flash controller voltage to the flash LED has been
+ below the minimum limit specific to the flash
+ * 0x80 - the input voltage of the flash controller is below
+ the limit under which strobing the flash at full
+ current will not be possible. The condition persists
+ until this flag is no longer set
+ * 0x100 - the temperature of the LED has exceeded its allowed
+ upper limit
--
1.7.9.5
^ permalink raw reply related [flat|nested] 9+ messages in thread
* Re: [PATCH/RFC v7 1/3] leds: Add support for setting brightness in a synchronous way
2014-11-12 16:09 ` [PATCH/RFC v7 1/3] leds: Add support for setting brightness in a synchronous way Jacek Anaszewski
@ 2014-11-13 18:43 ` Bryan Wu
0 siblings, 0 replies; 9+ messages in thread
From: Bryan Wu @ 2014-11-13 18:43 UTC (permalink / raw)
To: Jacek Anaszewski
Cc: Linux LED Subsystem, linux-media, sakari.ailus, Kyungmin Park,
b.zolnierkie, Richard Purdie
On Wed, Nov 12, 2014 at 8:09 AM, Jacek Anaszewski
<j.anaszewski@samsung.com> wrote:
> There are use cases when setting a LED brightness has to
> have immediate effect (e.g. setting a torch LED brightness).
> This patch extends LED subsystem to support such operations.
> The LED subsystem internal API __led_set_brightness is changed
> to led_set_brightness_async and new led_set_brightness_sync API
> is added.
>
Great, I do like this patch and just one pick coding style as below.
Thanks,
-Bryan
> Signed-off-by: Jacek Anaszewski <j.anaszewski@samsung.com>
> Acked-by: Kyungmin Park <kyungmin.park@samsung.com>
> Cc: Bryan Wu <cooloney@gmail.com>
> Cc: Richard Purdie <rpurdie@rpsys.net>
> ---
> drivers/leds/led-class.c | 10 ++++++----
> drivers/leds/led-core.c | 19 ++++++++++++++++---
> drivers/leds/leds.h | 20 ++++++++++++++++----
> drivers/leds/trigger/ledtrig-backlight.c | 8 ++++----
> drivers/leds/trigger/ledtrig-default-on.c | 2 +-
> drivers/leds/trigger/ledtrig-gpio.c | 6 +++---
> drivers/leds/trigger/ledtrig-heartbeat.c | 2 +-
> drivers/leds/trigger/ledtrig-oneshot.c | 4 ++--
> drivers/leds/trigger/ledtrig-transient.c | 10 ++++++----
> include/linux/leds.h | 8 ++++++++
> 10 files changed, 63 insertions(+), 26 deletions(-)
>
> diff --git a/drivers/leds/led-class.c b/drivers/leds/led-class.c
> index 65722de..dbeebac 100644
> --- a/drivers/leds/led-class.c
> +++ b/drivers/leds/led-class.c
> @@ -55,7 +55,7 @@ static ssize_t brightness_store(struct device *dev,
>
> if (state == LED_OFF)
> led_trigger_remove(led_cdev);
> - __led_set_brightness(led_cdev, state);
> + led_set_brightness(led_cdev, state);
>
> ret = size;
> unlock:
> @@ -109,7 +109,7 @@ static void led_timer_function(unsigned long data)
> unsigned long delay;
>
> if (!led_cdev->blink_delay_on || !led_cdev->blink_delay_off) {
> - __led_set_brightness(led_cdev, LED_OFF);
> + led_set_brightness_async(led_cdev, LED_OFF);
> return;
> }
>
> @@ -132,7 +132,7 @@ static void led_timer_function(unsigned long data)
> delay = led_cdev->blink_delay_off;
> }
>
> - __led_set_brightness(led_cdev, brightness);
> + led_set_brightness_async(led_cdev, brightness);
>
> /* Return in next iteration if led is in one-shot mode and we are in
> * the final blink state so that the led is toggled each delay_on +
> @@ -158,7 +158,7 @@ static void set_brightness_delayed(struct work_struct *ws)
>
> led_stop_software_blink(led_cdev);
>
> - __led_set_brightness(led_cdev, led_cdev->delayed_set_value);
> + led_set_brightness_async(led_cdev, led_cdev->delayed_set_value);
> }
>
> /**
> @@ -233,6 +233,8 @@ int led_classdev_register(struct device *parent, struct led_classdev *led_cdev)
> if (!led_cdev->max_brightness)
> led_cdev->max_brightness = LED_FULL;
>
> + led_cdev->flags |= SET_BRIGHTNESS_ASYNC;
> +
> led_update_brightness(led_cdev);
>
> INIT_WORK(&led_cdev->set_brightness_work, set_brightness_delayed);
> diff --git a/drivers/leds/led-core.c b/drivers/leds/led-core.c
> index be6d9fa..a745e32 100644
> --- a/drivers/leds/led-core.c
> +++ b/drivers/leds/led-core.c
> @@ -42,13 +42,13 @@ static void led_set_software_blink(struct led_classdev *led_cdev,
>
> /* never on - just set to off */
> if (!delay_on) {
> - __led_set_brightness(led_cdev, LED_OFF);
> + led_set_brightness_async(led_cdev, LED_OFF);
> return;
> }
>
> /* never off - just set to brightness */
> if (!delay_off) {
> - __led_set_brightness(led_cdev, led_cdev->blink_brightness);
> + led_set_brightness_async(led_cdev, led_cdev->blink_brightness);
> return;
> }
>
> @@ -117,6 +117,8 @@ EXPORT_SYMBOL_GPL(led_stop_software_blink);
> void led_set_brightness(struct led_classdev *led_cdev,
> enum led_brightness brightness)
> {
> + int ret = 0;
> +
> /* delay brightness setting if need to stop soft-blink timer */
> if (led_cdev->blink_delay_on || led_cdev->blink_delay_off) {
> led_cdev->delayed_set_value = brightness;
> @@ -124,7 +126,18 @@ void led_set_brightness(struct led_classdev *led_cdev,
> return;
> }
>
> - __led_set_brightness(led_cdev, brightness);
> + if (led_cdev->flags & SET_BRIGHTNESS_ASYNC) {
> + led_set_brightness_async(led_cdev, brightness);
> + return;
> + } else if (led_cdev->flags & SET_BRIGHTNESS_SYNC) {
> + ret = led_set_brightness_sync(led_cdev, brightness);
> + } else {
> + ret = -EINVAL;
> + }
> +
Since there is only one line in the {}, we don't need {} here:
+ if (led_cdev->flags & SET_BRIGHTNESS_ASYNC) {
+ led_set_brightness_async(led_cdev, brightness);
+ return;
+ } else if (led_cdev->flags & SET_BRIGHTNESS_SYNC)
+ ret = led_set_brightness_sync(led_cdev, brightness);
+ else
+ ret = -EINVAL;
+
> + if (ret < 0)
> + dev_dbg(led_cdev->dev, "Setting LED brightness failed (%d)\n",
> + ret);
> }
> EXPORT_SYMBOL(led_set_brightness);
>
> diff --git a/drivers/leds/leds.h b/drivers/leds/leds.h
> index 4c50365..2348dbd 100644
> --- a/drivers/leds/leds.h
> +++ b/drivers/leds/leds.h
> @@ -17,16 +17,28 @@
> #include <linux/rwsem.h>
> #include <linux/leds.h>
>
> -static inline void __led_set_brightness(struct led_classdev *led_cdev,
> +static inline void led_set_brightness_async(struct led_classdev *led_cdev,
> enum led_brightness value)
> {
> - if (value > led_cdev->max_brightness)
> - value = led_cdev->max_brightness;
> - led_cdev->brightness = value;
> + led_cdev->brightness = min(value, led_cdev->max_brightness);
> +
> if (!(led_cdev->flags & LED_SUSPENDED))
> led_cdev->brightness_set(led_cdev, value);
> }
>
> +static inline int led_set_brightness_sync(struct led_classdev *led_cdev,
> + enum led_brightness value)
> +{
> + int ret = 0;
> +
> + led_cdev->brightness = min(value, led_cdev->max_brightness);
> +
> + if (!(led_cdev->flags & LED_SUSPENDED))
> + ret = led_cdev->brightness_set_sync(led_cdev,
> + led_cdev->brightness);
> + return ret;
> +}
> +
> static inline int led_get_brightness(struct led_classdev *led_cdev)
> {
> return led_cdev->brightness;
> diff --git a/drivers/leds/trigger/ledtrig-backlight.c b/drivers/leds/trigger/ledtrig-backlight.c
> index 47e55aa..59eca17 100644
> --- a/drivers/leds/trigger/ledtrig-backlight.c
> +++ b/drivers/leds/trigger/ledtrig-backlight.c
> @@ -51,9 +51,9 @@ static int fb_notifier_callback(struct notifier_block *p,
>
> if ((n->old_status == UNBLANK) ^ n->invert) {
> n->brightness = led->brightness;
> - __led_set_brightness(led, LED_OFF);
> + led_set_brightness_async(led, LED_OFF);
> } else {
> - __led_set_brightness(led, n->brightness);
> + led_set_brightness_async(led, n->brightness);
> }
>
> n->old_status = new_status;
> @@ -89,9 +89,9 @@ static ssize_t bl_trig_invert_store(struct device *dev,
>
> /* After inverting, we need to update the LED. */
> if ((n->old_status == BLANK) ^ n->invert)
> - __led_set_brightness(led, LED_OFF);
> + led_set_brightness_async(led, LED_OFF);
> else
> - __led_set_brightness(led, n->brightness);
> + led_set_brightness_async(led, n->brightness);
>
> return num;
> }
> diff --git a/drivers/leds/trigger/ledtrig-default-on.c b/drivers/leds/trigger/ledtrig-default-on.c
> index 81a91be..6f38f88 100644
> --- a/drivers/leds/trigger/ledtrig-default-on.c
> +++ b/drivers/leds/trigger/ledtrig-default-on.c
> @@ -19,7 +19,7 @@
>
> static void defon_trig_activate(struct led_classdev *led_cdev)
> {
> - __led_set_brightness(led_cdev, led_cdev->max_brightness);
> + led_set_brightness_async(led_cdev, led_cdev->max_brightness);
> }
>
> static struct led_trigger defon_led_trigger = {
> diff --git a/drivers/leds/trigger/ledtrig-gpio.c b/drivers/leds/trigger/ledtrig-gpio.c
> index c86c418..4cc7040 100644
> --- a/drivers/leds/trigger/ledtrig-gpio.c
> +++ b/drivers/leds/trigger/ledtrig-gpio.c
> @@ -54,12 +54,12 @@ static void gpio_trig_work(struct work_struct *work)
>
> if (tmp) {
> if (gpio_data->desired_brightness)
> - __led_set_brightness(gpio_data->led,
> + led_set_brightness_async(gpio_data->led,
> gpio_data->desired_brightness);
> else
> - __led_set_brightness(gpio_data->led, LED_FULL);
> + led_set_brightness_async(gpio_data->led, LED_FULL);
> } else {
> - __led_set_brightness(gpio_data->led, LED_OFF);
> + led_set_brightness_async(gpio_data->led, LED_OFF);
> }
> }
>
> diff --git a/drivers/leds/trigger/ledtrig-heartbeat.c b/drivers/leds/trigger/ledtrig-heartbeat.c
> index 5c8464a..fea6871 100644
> --- a/drivers/leds/trigger/ledtrig-heartbeat.c
> +++ b/drivers/leds/trigger/ledtrig-heartbeat.c
> @@ -74,7 +74,7 @@ static void led_heartbeat_function(unsigned long data)
> break;
> }
>
> - __led_set_brightness(led_cdev, brightness);
> + led_set_brightness_async(led_cdev, brightness);
> mod_timer(&heartbeat_data->timer, jiffies + delay);
> }
>
> diff --git a/drivers/leds/trigger/ledtrig-oneshot.c b/drivers/leds/trigger/ledtrig-oneshot.c
> index cb4c746..fbd02cd 100644
> --- a/drivers/leds/trigger/ledtrig-oneshot.c
> +++ b/drivers/leds/trigger/ledtrig-oneshot.c
> @@ -63,9 +63,9 @@ static ssize_t led_invert_store(struct device *dev,
> oneshot_data->invert = !!state;
>
> if (oneshot_data->invert)
> - __led_set_brightness(led_cdev, LED_FULL);
> + led_set_brightness_async(led_cdev, LED_FULL);
> else
> - __led_set_brightness(led_cdev, LED_OFF);
> + led_set_brightness_async(led_cdev, LED_OFF);
>
> return size;
> }
> diff --git a/drivers/leds/trigger/ledtrig-transient.c b/drivers/leds/trigger/ledtrig-transient.c
> index e5abc00..3c34de4 100644
> --- a/drivers/leds/trigger/ledtrig-transient.c
> +++ b/drivers/leds/trigger/ledtrig-transient.c
> @@ -41,7 +41,7 @@ static void transient_timer_function(unsigned long data)
> struct transient_trig_data *transient_data = led_cdev->trigger_data;
>
> transient_data->activate = 0;
> - __led_set_brightness(led_cdev, transient_data->restore_state);
> + led_set_brightness_async(led_cdev, transient_data->restore_state);
> }
>
> static ssize_t transient_activate_show(struct device *dev,
> @@ -72,7 +72,8 @@ static ssize_t transient_activate_store(struct device *dev,
> if (state == 0 && transient_data->activate == 1) {
> del_timer(&transient_data->timer);
> transient_data->activate = state;
> - __led_set_brightness(led_cdev, transient_data->restore_state);
> + led_set_brightness_async(led_cdev,
> + transient_data->restore_state);
> return size;
> }
>
> @@ -80,7 +81,7 @@ static ssize_t transient_activate_store(struct device *dev,
> if (state == 1 && transient_data->activate == 0 &&
> transient_data->duration != 0) {
> transient_data->activate = state;
> - __led_set_brightness(led_cdev, transient_data->state);
> + led_set_brightness_async(led_cdev, transient_data->state);
> transient_data->restore_state =
> (transient_data->state == LED_FULL) ? LED_OFF : LED_FULL;
> mod_timer(&transient_data->timer,
> @@ -203,7 +204,8 @@ static void transient_trig_deactivate(struct led_classdev *led_cdev)
>
> if (led_cdev->activated) {
> del_timer_sync(&transient_data->timer);
> - __led_set_brightness(led_cdev, transient_data->restore_state);
> + led_set_brightness_async(led_cdev,
> + transient_data->restore_state);
> device_remove_file(led_cdev->dev, &dev_attr_activate);
> device_remove_file(led_cdev->dev, &dev_attr_duration);
> device_remove_file(led_cdev->dev, &dev_attr_state);
> diff --git a/include/linux/leds.h b/include/linux/leds.h
> index 3737a5a..cfceef3 100644
> --- a/include/linux/leds.h
> +++ b/include/linux/leds.h
> @@ -44,11 +44,19 @@ struct led_classdev {
> #define LED_BLINK_ONESHOT_STOP (1 << 18)
> #define LED_BLINK_INVERT (1 << 19)
> #define LED_SYSFS_DISABLE (1 << 20)
> +#define SET_BRIGHTNESS_ASYNC (1 << 21)
> +#define SET_BRIGHTNESS_SYNC (1 << 22)
>
> /* Set LED brightness level */
> /* Must not sleep, use a workqueue if needed */
> void (*brightness_set)(struct led_classdev *led_cdev,
> enum led_brightness brightness);
> + /*
> + * Set LED brightness level immediately - it can block the caller for
> + * the time required for accessing a LED device register.
> + */
> + int (*brightness_set_sync)(struct led_classdev *led_cdev,
> + enum led_brightness brightness);
> /* Get LED brightness level */
> enum led_brightness (*brightness_get)(struct led_classdev *led_cdev);
>
> --
> 1.7.9.5
>
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH/RFC v7 3/3] Documentation: leds: Add description of LED Flash Class extension
2014-11-12 16:09 ` [PATCH/RFC v7 3/3] Documentation: leds: Add description of LED Flash Class extension Jacek Anaszewski
@ 2014-11-13 18:58 ` Bryan Wu
2014-11-14 10:21 ` Jacek Anaszewski
0 siblings, 1 reply; 9+ messages in thread
From: Bryan Wu @ 2014-11-13 18:58 UTC (permalink / raw)
To: Jacek Anaszewski
Cc: Linux LED Subsystem, linux-media, sakari.ailus, Kyungmin Park,
b.zolnierkie, Richard Purdie
On Wed, Nov 12, 2014 at 8:09 AM, Jacek Anaszewski
<j.anaszewski@samsung.com> wrote:
> The documentation being added contains overall description of the
> LED Flash Class and the related sysfs attributes.
>
> Signed-off-by: Jacek Anaszewski <j.anaszewski@samsung.com>
> Acked-by: Kyungmin Park <kyungmin.park@samsung.com>
> Cc: Bryan Wu <cooloney@gmail.com>
> Cc: Richard Purdie <rpurdie@rpsys.net>
> ---
> Documentation/leds/leds-class-flash.txt | 39 +++++++++++++++++++++++++++++++
> 1 file changed, 39 insertions(+)
> create mode 100644 Documentation/leds/leds-class-flash.txt
>
> diff --git a/Documentation/leds/leds-class-flash.txt b/Documentation/leds/leds-class-flash.txt
> new file mode 100644
> index 0000000..0164329
> --- /dev/null
> +++ b/Documentation/leds/leds-class-flash.txt
> @@ -0,0 +1,39 @@
> +
> +Flash LED handling under Linux
> +==============================
> +
> +Some LED devices support two modes - torch and flash. In order to enable
I think I asked this question before, Torch, Flash and Indicator. As
you answered torch is implemented by sync led brightness set operation
in our LEDS_CLASS and Flash is implemented in this LEDS_CLASS_FLASH.
I suggest put this information in document or code comments. Then
people know how to use torch and flash.
For indicator I still don't know why we need this since indicator is
like blinking and it should be support by LEDS_CLASS right?
Flash is for some camera capture, right?
> +support for flash LEDs CONFIG_LEDS_CLASS_FLASH symbol must be defined
> +in the kernel config. A flash LED driver must register in the LED subsystem
> +with led_classdev_flash_register to gain flash capabilities.
> +
> +Following sysfs attributes are exposed for controlling flash led devices:
> +
> + - flash_brightness - flash LED brightness in microamperes (RW)
> + - max_flash_brightness - maximum available flash LED brightness (RO)
> + - indicator_brightness - privacy LED brightness in microamperes (RW)
> + - max_indicator_brightness - maximum privacy LED brightness in
> + microamperes (RO)
What's the privacy mean here?
> + - flash_timeout - flash strobe duration in microseconds (RW)
> + - max_flash_timeout - maximum available flash strobe duration (RO)
> + - flash_strobe - flash strobe state (RW)
> + - flash_fault - bitmask of flash faults that may have occurred,
> + possible flags are:
> + * 0x01 - flash controller voltage to the flash LED has exceeded
> + the limit specific to the flash controller
> + * 0x02 - the flash strobe was still on when the timeout set by
> + the user has expired; not all flash controllers may
> + set this in all such conditions
> + * 0x04 - the flash controller has overheated
> + * 0x08 - the short circuit protection of the flash controller
> + has been triggered
> + * 0x10 - current in the LED power supply has exceeded the limit
> + specific to the flash controller
> + * 0x40 - flash controller voltage to the flash LED has been
> + below the minimum limit specific to the flash
> + * 0x80 - the input voltage of the flash controller is below
> + the limit under which strobing the flash at full
> + current will not be possible. The condition persists
> + until this flag is no longer set
> + * 0x100 - the temperature of the LED has exceeded its allowed
> + upper limit
Are these error code the same for all the LED controller? Or just for
some specific chip?
> --
> 1.7.9.5
>
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH/RFC v7 3/3] Documentation: leds: Add description of LED Flash Class extension
2014-11-13 18:58 ` Bryan Wu
@ 2014-11-14 10:21 ` Jacek Anaszewski
0 siblings, 0 replies; 9+ messages in thread
From: Jacek Anaszewski @ 2014-11-14 10:21 UTC (permalink / raw)
To: Bryan Wu
Cc: Linux LED Subsystem, linux-media, sakari.ailus, Kyungmin Park,
b.zolnierkie, Richard Purdie
Hi Bryan,
Thanks for a review.
On 11/13/2014 07:58 PM, Bryan Wu wrote:
> On Wed, Nov 12, 2014 at 8:09 AM, Jacek Anaszewski
> <j.anaszewski@samsung.com> wrote:
>> The documentation being added contains overall description of the
>> LED Flash Class and the related sysfs attributes.
>>
>> Signed-off-by: Jacek Anaszewski <j.anaszewski@samsung.com>
>> Acked-by: Kyungmin Park <kyungmin.park@samsung.com>
>> Cc: Bryan Wu <cooloney@gmail.com>
>> Cc: Richard Purdie <rpurdie@rpsys.net>
>> ---
>> Documentation/leds/leds-class-flash.txt | 39 +++++++++++++++++++++++++++++++
>> 1 file changed, 39 insertions(+)
>> create mode 100644 Documentation/leds/leds-class-flash.txt
>>
>> diff --git a/Documentation/leds/leds-class-flash.txt b/Documentation/leds/leds-class-flash.txt
>> new file mode 100644
>> index 0000000..0164329
>> --- /dev/null
>> +++ b/Documentation/leds/leds-class-flash.txt
>> @@ -0,0 +1,39 @@
>> +
>> +Flash LED handling under Linux
>> +==============================
>> +
>> +Some LED devices support two modes - torch and flash. In order to enable
>
> I think I asked this question before, Torch, Flash and Indicator. As
> you answered torch is implemented by sync led brightness set operation
> in our LEDS_CLASS and Flash is implemented in this LEDS_CLASS_FLASH.
>
> I suggest put this information in document or code comments. Then
> people know how to use torch and flash.
Good point.
> For indicator I still don't know why we need this since indicator is
> like blinking and it should be support by LEDS_CLASS right?
Indicator led is strictly related to flash devices. It is also called a
"privacy led" because of its purpose - protecting a privacy of a person
being recorded by providing a light signal signifying that a camera is
on. It is a low current led, but some devices use the same led as
for torch and flash and only apply reduced current in the indicator
mode.
In the V4L2 subsystem I see only one driver supporting indicator
leds: /drivers/media/i2c/as3645a.c. It looks like indicator intensity
can be set only when flash mode is V4L2_FLASH_LED_MODE_NONE, i.e. torch
and flash leds cannot be active simultaneously with indicator led.
It is reasonable, as active torch led is a sufficient signalization
of recording.
In the LED subsystem I also see indicators in some drivers,
e.g. leds-lm355x.c, but they are registered as a separate LED class
devices. Moreover the driver adds also a "pattern" sysfs attribute
for choosing indicator blinking pattern so that is something to be
added to the LED Flash class.
I think that similar improvement to the V4L2 Flash API should be made.
Sakari, what is your opinion?
> Flash is for some camera capture, right?
>
>> +support for flash LEDs CONFIG_LEDS_CLASS_FLASH symbol must be defined
>> +in the kernel config. A flash LED driver must register in the LED subsystem
>> +with led_classdev_flash_register to gain flash capabilities.
>> +
>> +Following sysfs attributes are exposed for controlling flash led devices:
>> +
>> + - flash_brightness - flash LED brightness in microamperes (RW)
>> + - max_flash_brightness - maximum available flash LED brightness (RO)
>> + - indicator_brightness - privacy LED brightness in microamperes (RW)
>> + - max_indicator_brightness - maximum privacy LED brightness in
>> + microamperes (RO)
>
> What's the privacy mean here?
Indeed, consistent naming should be applied, so I will modify it to:
"maximum indicator LED brightness in microaperes (RO)"
>> + - flash_timeout - flash strobe duration in microseconds (RW)
>> + - max_flash_timeout - maximum available flash strobe duration (RO)
>> + - flash_strobe - flash strobe state (RW)
>> + - flash_fault - bitmask of flash faults that may have occurred,
>> + possible flags are:
>> + * 0x01 - flash controller voltage to the flash LED has exceeded
>> + the limit specific to the flash controller
>> + * 0x02 - the flash strobe was still on when the timeout set by
>> + the user has expired; not all flash controllers may
>> + set this in all such conditions
>> + * 0x04 - the flash controller has overheated
>> + * 0x08 - the short circuit protection of the flash controller
>> + has been triggered
>> + * 0x10 - current in the LED power supply has exceeded the limit
>> + specific to the flash controller
>> + * 0x40 - flash controller voltage to the flash LED has been
>> + below the minimum limit specific to the flash
>> + * 0x80 - the input voltage of the flash controller is below
>> + the limit under which strobing the flash at full
>> + current will not be possible. The condition persists
>> + until this flag is no longer set
>> + * 0x100 - the temperature of the LED has exceeded its allowed
>> + upper limit
>
> Are these error code the same for all the LED controller? Or just for
> some specific chip?
They are generic error codes, and map directly to V4L2 Flash errors.
Error descriptions were copied from the V4L2 Flash documentation.
Best Regards,
Jacek Anaszewski
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH/RFC v7 2/3] leds: Add LED Flash Class wrapper to LED subsystem
2014-11-12 16:09 ` [PATCH/RFC v7 2/3] leds: Add LED Flash Class wrapper to LED subsystem Jacek Anaszewski
@ 2014-11-27 8:43 ` Sakari Ailus
2014-11-28 9:34 ` Jacek Anaszewski
0 siblings, 1 reply; 9+ messages in thread
From: Sakari Ailus @ 2014-11-27 8:43 UTC (permalink / raw)
To: Jacek Anaszewski
Cc: linux-leds, linux-media, sakari.ailus, kyungmin.park,
b.zolnierkie, Bryan Wu, Richard Purdie
Hi Jacek,
Thank you for the patch.
One generic question: how do you support flash controllers with multiple
flash LEDs? I thought that once was a part of the patchset?
On Wed, Nov 12, 2014 at 05:09:16PM +0100, Jacek Anaszewski wrote:
> Some LED devices support two operation modes - torch and flash.
> This patch provides support for flash LED devices in the LED subsystem
> by introducing new sysfs attributes and kernel internal interface.
> The attributes being introduced are: flash_brightness, flash_strobe,
> flash_timeout, max_flash_timeout, max_flash_brightness, flash_fault,
> indicator_brightness and max_indicator_brightness. All the flash
> related features are placed in a separate module.
>
> The modifications aim to be compatible with V4L2 framework requirements
> related to the flash devices management. The design assumes that V4L2
> sub-device can take of the LED class device control and communicate
> with it through the kernel internal interface. When V4L2 Flash sub-device
> file is opened, the LED class device sysfs interface is made
> unavailable.
>
> Signed-off-by: Jacek Anaszewski <j.anaszewski@samsung.com>
> Acked-by: Kyungmin Park <kyungmin.park@samsung.com>
> Cc: Bryan Wu <cooloney@gmail.com>
> Cc: Richard Purdie <rpurdie@rpsys.net>
> ---
> drivers/leds/Kconfig | 11 +
> drivers/leds/Makefile | 1 +
> drivers/leds/led-class-flash.c | 511 +++++++++++++++++++++++++++++++++++++++
> drivers/leds/led-class.c | 4 +
> include/linux/led-class-flash.h | 229 ++++++++++++++++++
> include/linux/leds.h | 3 +
> 6 files changed, 759 insertions(+)
> create mode 100644 drivers/leds/led-class-flash.c
> create mode 100644 include/linux/led-class-flash.h
>
> diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig
> index 808095b..50c4370 100644
> --- a/drivers/leds/Kconfig
> +++ b/drivers/leds/Kconfig
> @@ -19,6 +19,17 @@ config LEDS_CLASS
> This option enables the led sysfs class in /sys/class/leds. You'll
> need this to do anything useful with LEDs. If unsure, say N.
>
> +config LEDS_CLASS_FLASH
> + tristate "LED Flash Class Support"
> + depends on LEDS_CLASS
> + depends on OF
Why the dependency? I don't see any references to Open Firmware.
> + help
> + This option enables the flash led sysfs class in /sys/class/leds.
> + It wrapps LED Class and adds flash LEDs specific sysfs attributes
> + and kernel internal API to it. You'll need this to provide support
> + for the flash related features of a LED device. It can be built
> + as a module.
> +
> comment "LED drivers"
>
> config LEDS_88PM860X
> diff --git a/drivers/leds/Makefile b/drivers/leds/Makefile
> index a2b1647..73c0cec 100644
> --- a/drivers/leds/Makefile
> +++ b/drivers/leds/Makefile
> @@ -2,6 +2,7 @@
> # LED Core
> obj-$(CONFIG_NEW_LEDS) += led-core.o
> obj-$(CONFIG_LEDS_CLASS) += led-class.o
> +obj-$(CONFIG_LEDS_CLASS_FLASH) += led-class-flash.o
> obj-$(CONFIG_LEDS_TRIGGERS) += led-triggers.o
>
> # LED Platform Drivers
> diff --git a/drivers/leds/led-class-flash.c b/drivers/leds/led-class-flash.c
> new file mode 100644
> index 0000000..bec99f6
> --- /dev/null
> +++ b/drivers/leds/led-class-flash.c
> @@ -0,0 +1,511 @@
> +/*
> + * LED Flash Class interface
> + *
> + * Copyright (C) 2014 Samsung Electronics Co., Ltd.
> + * Author: Jacek Anaszewski <j.anaszewski@samsung.com>
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License version 2 as
> + * published by the Free Software Foundation.
> + */
> +
> +#include <linux/device.h>
> +#include <linux/init.h>
> +#include <linux/leds.h>
> +#include <linux/led-class-flash.h>
Nitpicking... "-" comes before "s".
> +#include <linux/module.h>
> +#include <linux/slab.h>
> +#include "leds.h"
> +
> +#define has_flash_op(flash, op) \
> + (flash && flash->ops->op)
> +
> +#define call_flash_op(flash, op, args...) \
> + ((has_flash_op(flash, op)) ? \
> + (flash->ops->op(flash, args)) : \
> + -EINVAL)
> +
> +static ssize_t flash_brightness_store(struct device *dev,
> + struct device_attribute *attr, const char *buf, size_t size)
> +{
> + struct led_classdev *led_cdev = dev_get_drvdata(dev);
> + struct led_classdev_flash *flash = lcdev_to_flash(led_cdev);
> + unsigned long state;
> + ssize_t ret;
> +
> + mutex_lock(&led_cdev->led_access);
> +
> + if (led_sysfs_is_disabled(led_cdev)) {
> + ret = -EBUSY;
> + goto unlock;
> + }
> +
> + ret = kstrtoul(buf, 10, &state);
> + if (ret)
> + goto unlock;
> +
> + ret = led_set_flash_brightness(flash, state);
> + if (ret < 0)
> + goto unlock;
> +
> + ret = size;
> +unlock:
> + mutex_unlock(&led_cdev->led_access);
> + return ret;
> +}
> +
> +static ssize_t flash_brightness_show(struct device *dev,
> + struct device_attribute *attr, char *buf)
> +{
> + struct led_classdev *led_cdev = dev_get_drvdata(dev);
> + struct led_classdev_flash *flash = lcdev_to_flash(led_cdev);
> +
> + /* no lock needed for this */
> + led_update_flash_brightness(flash);
> +
> + return sprintf(buf, "%u\n", flash->brightness.val);
> +}
> +static DEVICE_ATTR_RW(flash_brightness);
> +
> +static ssize_t max_flash_brightness_show(struct device *dev,
> + struct device_attribute *attr, char *buf)
> +{
> + struct led_classdev *led_cdev = dev_get_drvdata(dev);
> + struct led_classdev_flash *flash = lcdev_to_flash(led_cdev);
> +
> + return sprintf(buf, "%u\n", flash->brightness.max);
> +}
> +static DEVICE_ATTR_RO(max_flash_brightness);
> +
> +static ssize_t indicator_brightness_store(struct device *dev,
> + struct device_attribute *attr, const char *buf, size_t size)
> +{
> + struct led_classdev *led_cdev = dev_get_drvdata(dev);
> + struct led_classdev_flash *flash = lcdev_to_flash(led_cdev);
> + unsigned long state;
> + ssize_t ret;
> +
> + mutex_lock(&led_cdev->led_access);
> +
> + if (led_sysfs_is_disabled(led_cdev)) {
> + ret = -EBUSY;
> + goto unlock;
> + }
> +
> + ret = kstrtoul(buf, 10, &state);
> + if (ret)
> + goto unlock;
> +
> + ret = led_set_indicator_brightness(flash, state);
> + if (ret < 0)
> + goto unlock;
> +
> + ret = size;
> +unlock:
> + mutex_unlock(&led_cdev->led_access);
> + return ret;
> +}
> +
> +static ssize_t indicator_brightness_show(struct device *dev,
> + struct device_attribute *attr, char *buf)
> +{
> + struct led_classdev *led_cdev = dev_get_drvdata(dev);
> + struct led_classdev_flash *flash = lcdev_to_flash(led_cdev);
> +
> + /* no lock needed for this */
> + led_update_indicator_brightness(flash);
> +
> + return sprintf(buf, "%u\n", flash->indicator_brightness->val);
> +}
> +static DEVICE_ATTR_RW(indicator_brightness);
> +
> +static ssize_t max_indicator_brightness_show(struct device *dev,
> + struct device_attribute *attr, char *buf)
> +{
> + struct led_classdev *led_cdev = dev_get_drvdata(dev);
> + struct led_classdev_flash *flash = lcdev_to_flash(led_cdev);
> +
> + return sprintf(buf, "%u\n", flash->indicator_brightness->max);
> +}
> +static DEVICE_ATTR_RO(max_indicator_brightness);
> +
> +static ssize_t flash_strobe_store(struct device *dev,
> + struct device_attribute *attr, const char *buf, size_t size)
> +{
> + struct led_classdev *led_cdev = dev_get_drvdata(dev);
> + struct led_classdev_flash *flash = lcdev_to_flash(led_cdev);
> + unsigned long state;
> + ssize_t ret = -EINVAL;
> +
> + mutex_lock(&led_cdev->led_access);
> +
> + if (led_sysfs_is_disabled(led_cdev)) {
> + ret = -EBUSY;
> + goto unlock;
> + }
> +
> + ret = kstrtoul(buf, 10, &state);
> + if (ret)
> + goto unlock;
> +
> + if (state < 0 || state > 1) {
> + ret = -EINVAL;
> + goto unlock;
> + }
> +
> + ret = led_set_flash_strobe(flash, state);
> + if (ret < 0)
> + goto unlock;
> + ret = size;
> +unlock:
> + mutex_unlock(&led_cdev->led_access);
> + return ret;
> +}
> +
> +static ssize_t flash_strobe_show(struct device *dev,
> + struct device_attribute *attr, char *buf)
> +{
> + struct led_classdev *led_cdev = dev_get_drvdata(dev);
> + struct led_classdev_flash *flash = lcdev_to_flash(led_cdev);
> + bool state;
> + int ret;
> +
> + /* no lock needed for this */
> + ret = led_get_flash_strobe(flash, &state);
> + if (ret < 0)
> + return ret;
> +
> + return sprintf(buf, "%u\n", state);
> +}
> +static DEVICE_ATTR_RW(flash_strobe);
> +
> +static ssize_t flash_timeout_store(struct device *dev,
> + struct device_attribute *attr, const char *buf, size_t size)
> +{
> + struct led_classdev *led_cdev = dev_get_drvdata(dev);
> + struct led_classdev_flash *flash = lcdev_to_flash(led_cdev);
> + unsigned long flash_timeout;
> + ssize_t ret;
> +
> + mutex_lock(&led_cdev->led_access);
> +
> + if (led_sysfs_is_disabled(led_cdev)) {
> + ret = -EBUSY;
> + goto unlock;
> + }
> +
> + ret = kstrtoul(buf, 10, &flash_timeout);
> + if (ret)
> + goto unlock;
> +
> + ret = led_set_flash_timeout(flash, flash_timeout);
> + if (ret < 0)
> + goto unlock;
> +
> + ret = size;
> +unlock:
> + mutex_unlock(&led_cdev->led_access);
> + return ret;
> +}
> +
> +static ssize_t flash_timeout_show(struct device *dev,
> + struct device_attribute *attr, char *buf)
> +{
> + struct led_classdev *led_cdev = dev_get_drvdata(dev);
> + struct led_classdev_flash *flash = lcdev_to_flash(led_cdev);
> +
> + return sprintf(buf, "%u\n", flash->timeout.val);
> +}
> +static DEVICE_ATTR_RW(flash_timeout);
> +
> +static ssize_t max_flash_timeout_show(struct device *dev,
> + struct device_attribute *attr, char *buf)
> +{
> + struct led_classdev *led_cdev = dev_get_drvdata(dev);
> + struct led_classdev_flash *flash = lcdev_to_flash(led_cdev);
> +
> + return sprintf(buf, "%u\n", flash->timeout.max);
> +}
> +static DEVICE_ATTR_RO(max_flash_timeout);
> +
> +static ssize_t flash_fault_show(struct device *dev,
> + struct device_attribute *attr, char *buf)
> +{
> + struct led_classdev *led_cdev = dev_get_drvdata(dev);
> + struct led_classdev_flash *flash = lcdev_to_flash(led_cdev);
> + u32 fault;
> + int ret;
> +
> + ret = led_get_flash_fault(flash, &fault);
> + if (ret < 0)
> + return -EINVAL;
> +
> + return sprintf(buf, "0x%8.8x\n", fault);
> +}
> +static DEVICE_ATTR_RO(flash_fault);
> +
> +static struct attribute *led_flash_strobe_attrs[] = {
> + &dev_attr_flash_strobe.attr,
> + NULL,
> +};
> +
> +static struct attribute *led_flash_indicator_attrs[] = {
> + &dev_attr_indicator_brightness.attr,
> + &dev_attr_max_indicator_brightness.attr,
> + NULL,
> +};
> +
> +static struct attribute *led_flash_timeout_attrs[] = {
> + &dev_attr_flash_timeout.attr,
> + &dev_attr_max_flash_timeout.attr,
> + NULL,
> +};
> +
> +static struct attribute *led_flash_brightness_attrs[] = {
> + &dev_attr_flash_brightness.attr,
> + &dev_attr_max_flash_brightness.attr,
> + NULL,
> +};
> +
> +static struct attribute *led_flash_fault_attrs[] = {
> + &dev_attr_flash_fault.attr,
> + NULL,
> +};
> +
> +static const struct attribute_group led_flash_strobe_group = {
> + .attrs = led_flash_strobe_attrs,
> +};
> +
> +static const struct attribute_group led_flash_indicator_group = {
> + .attrs = led_flash_indicator_attrs,
> +};
> +
> +static const struct attribute_group led_flash_timeout_group = {
> + .attrs = led_flash_timeout_attrs,
> +};
> +
> +static const struct attribute_group led_flash_brightness_group = {
> + .attrs = led_flash_brightness_attrs,
> +};
> +
> +static const struct attribute_group led_flash_fault_group = {
> + .attrs = led_flash_fault_attrs,
> +};
> +
> +static const struct attribute_group *flash_groups[] = {
> + &led_flash_strobe_group,
> + NULL,
> + NULL,
> + NULL,
> + NULL,
> + NULL,
> +};
> +
> +static void led_flash_resume(struct led_classdev *led_cdev)
> +{
> + struct led_classdev_flash *flash = lcdev_to_flash(led_cdev);
> +
> + call_flash_op(flash, flash_brightness_set, flash->brightness.val);
> + call_flash_op(flash, timeout_set, flash->timeout.val);
> + call_flash_op(flash, indicator_brightness_set,
> + flash->indicator_brightness->val);
> +}
> +
> +static void led_flash_init_sysfs_groups(struct led_classdev_flash *flash)
> +{
> + struct led_classdev *led_cdev = &flash->led_cdev;
> + const struct led_flash_ops *ops = flash->ops;
> + int num_sysfs_groups = 1;
> +
> + if (led_cdev->flags & LED_DEV_CAP_INDICATOR)
> + flash_groups[num_sysfs_groups++] = &led_flash_indicator_group;
> +
> + if (ops->flash_brightness_set)
> + flash_groups[num_sysfs_groups++] = &led_flash_brightness_group;
> +
> + if (ops->timeout_set)
> + flash_groups[num_sysfs_groups++] = &led_flash_timeout_group;
> +
> + if (ops->fault_get)
> + flash_groups[num_sysfs_groups++] = &led_flash_fault_group;
> +
> + led_cdev->groups = flash_groups;
> +}
> +
> +int led_classdev_flash_register(struct device *parent,
> + struct led_classdev_flash *flash)
> +{
> + struct led_classdev *led_cdev;
> + const struct led_flash_ops *ops;
> + int ret;
> +
> + if (!flash)
> + return -EINVAL;
> +
> + led_cdev = &flash->led_cdev;
> +
> + if (led_cdev->flags & LED_DEV_CAP_FLASH) {
> + if (!led_cdev->brightness_set_sync)
> + return -EINVAL;
> +
> + ops = flash->ops;
> + if (!ops || !ops->strobe_set)
> + return -EINVAL;
> +
> + if ((led_cdev->flags & LED_DEV_CAP_INDICATOR) &&
> + (!flash->indicator_brightness ||
> + !ops->indicator_brightness_set))
> + return -EINVAL;
> +
> + led_cdev->flash_resume = led_flash_resume;
> + }
> +
> + /* Select the sysfs attributes to be created for the device */
> + led_flash_init_sysfs_groups(flash);
> +
> + /* Register led class device */
> + ret = led_classdev_register(parent, led_cdev);
> + if (ret < 0)
> + return ret;
> +
> + /* Setting a torch brightness needs to have immediate effect */
> + led_cdev->flags &= ~SET_BRIGHTNESS_ASYNC;
> + led_cdev->flags |= SET_BRIGHTNESS_SYNC;
> +
> + return 0;
> +}
> +EXPORT_SYMBOL_GPL(led_classdev_flash_register);
> +
> +void led_classdev_flash_unregister(struct led_classdev_flash *flash)
> +{
> + if (!flash)
> + return;
> +
> + led_classdev_unregister(&flash->led_cdev);
> +}
> +EXPORT_SYMBOL_GPL(led_classdev_flash_unregister);
> +
> +int led_set_flash_strobe(struct led_classdev_flash *flash, bool state)
> +{
> + return call_flash_op(flash, strobe_set, state);
> +}
> +EXPORT_SYMBOL_GPL(led_set_flash_strobe);
> +
> +int led_get_flash_strobe(struct led_classdev_flash *flash, bool *state)
> +{
> + return call_flash_op(flash, strobe_get, state);
> +}
> +EXPORT_SYMBOL_GPL(led_get_flash_strobe);
> +
> +static void led_clamp_align(struct led_flash_setting *s)
> +{
> + u32 v, offset;
> +
> + v = s->val + s->step / 2;
> + v = clamp(v, s->min, s->max);
> + offset = v - s->min;
> + offset = s->step * (offset / s->step);
You could use the rounddown() macro. I.e.
rounddown(v - s->min, s->step) + s->min;
> + s->val = s->min + offset;
> +}
> +
> +int led_set_flash_timeout(struct led_classdev_flash *flash, u32 timeout)
> +{
> + struct led_classdev *led_cdev = &flash->led_cdev;
> + struct led_flash_setting *s = &flash->timeout;
> + int ret = 0;
> +
> + s->val = timeout;
> + led_clamp_align(s);
> +
> + if (!(led_cdev->flags & LED_SUSPENDED))
> + ret = call_flash_op(flash, timeout_set, s->val);
> +
> + return ret;
ret is pretty much redundant here.
> +}
> +EXPORT_SYMBOL_GPL(led_set_flash_timeout);
> +
> +int led_get_flash_fault(struct led_classdev_flash *flash, u32 *fault)
> +{
> + return call_flash_op(flash, fault_get, fault);
> +}
> +EXPORT_SYMBOL_GPL(led_get_flash_fault);
> +
> +int led_set_flash_brightness(struct led_classdev_flash *flash,
> + u32 brightness)
> +{
> + struct led_classdev *led_cdev = &flash->led_cdev;
> + struct led_flash_setting *s = &flash->brightness;
> + int ret = 0;
> +
> + s->val = brightness;
> + led_clamp_align(s);
> +
> + if (!(led_cdev->flags & LED_SUSPENDED))
> + ret = call_flash_op(flash, flash_brightness_set, s->val);
Same here.
> +
> + return ret;
> +}
> +EXPORT_SYMBOL_GPL(led_set_flash_brightness);
> +
> +int led_update_flash_brightness(struct led_classdev_flash *flash)
> +{
> + struct led_flash_setting *s = &flash->brightness;
> + u32 brightness;
> + int ret = 0;
> +
> + if (has_flash_op(flash, flash_brightness_get)) {
> + ret = call_flash_op(flash, flash_brightness_get,
> + &brightness);
> + if (ret < 0)
> + return ret;
> + s->val = brightness;
> + }
> +
> + return ret;
Shouldn't ret be always zero here? You can declare ret inside if () { }.
Same for brightness.
> +}
> +EXPORT_SYMBOL_GPL(led_update_flash_brightness);
> +
> +int led_set_indicator_brightness(struct led_classdev_flash *flash,
> + u32 brightness)
> +{
> + struct led_classdev *led_cdev = &flash->led_cdev;
> + struct led_flash_setting *s = flash->indicator_brightness;
> + int ret = 0;
> +
> + if (!s)
> + return -EINVAL;
> +
> + s->val = brightness;
> + led_clamp_align(s);
> +
> + if (!(led_cdev->flags & LED_SUSPENDED))
> + ret = call_flash_op(flash, indicator_brightness_set, s->val);
> +
> + return ret;
> +}
> +EXPORT_SYMBOL_GPL(led_set_indicator_brightness);
> +
> +int led_update_indicator_brightness(struct led_classdev_flash *flash)
> +{
> + struct led_flash_setting *s = flash->indicator_brightness;
> + u32 brightness;
> + int ret = 0;
> +
> + if (!s)
> + return -EINVAL;
> +
> + if (has_flash_op(flash, indicator_brightness_get)) {
> + ret = call_flash_op(flash, indicator_brightness_get,
> + &brightness);
> + if (ret < 0)
> + return ret;
> + s->val = brightness;
> + }
> +
> + return ret;
> +}
> +EXPORT_SYMBOL_GPL(led_update_indicator_brightness);
> +
> +MODULE_AUTHOR("Jacek Anaszewski <j.anaszewski@samsung.com>");
> +MODULE_LICENSE("GPL");
> +MODULE_DESCRIPTION("LED Flash Class Interface");
> diff --git a/drivers/leds/led-class.c b/drivers/leds/led-class.c
> index dbeebac..02564c5 100644
> --- a/drivers/leds/led-class.c
> +++ b/drivers/leds/led-class.c
> @@ -179,6 +179,10 @@ EXPORT_SYMBOL_GPL(led_classdev_suspend);
> void led_classdev_resume(struct led_classdev *led_cdev)
> {
> led_cdev->brightness_set(led_cdev, led_cdev->brightness);
> +
> + if (led_cdev->flash_resume)
> + led_cdev->flash_resume(led_cdev);
> +
> led_cdev->flags &= ~LED_SUSPENDED;
> }
> EXPORT_SYMBOL_GPL(led_classdev_resume);
> diff --git a/include/linux/led-class-flash.h b/include/linux/led-class-flash.h
> new file mode 100644
> index 0000000..df95b8a
> --- /dev/null
> +++ b/include/linux/led-class-flash.h
> @@ -0,0 +1,229 @@
> +/*
> + * LED Flash Class interface
> + *
> + * Copyright (C) 2014 Samsung Electronics Co., Ltd.
> + * Author: Jacek Anaszewski <j.anaszewski@samsung.com>
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License version 2 as
> + * published by the Free Software Foundation.
> + *
> + */
> +#ifndef __LINUX_FLASH_LEDS_H_INCLUDED
> +#define __LINUX_FLASH_LEDS_H_INCLUDED
> +
> +#include <linux/leds.h>
If you use the V4L2 flash fault definitions, you should include
uapi/linux/v4l2-controls.h .
> +struct led_classdev_flash;
> +struct device_node;
> +
> +/*
> + * Supported led fault bits - must be kept in synch
> + * with V4L2_FLASH_FAULT bits.
> + */
> +#define LED_FAULT_OVER_VOLTAGE V4L2_FLASH_FAULT_OVER_VOLTAGE
> +#define LED_FAULT_TIMEOUT V4L2_FLASH_FAULT_TIMEOUT
> +#define LED_FAULT_OVER_TEMPERATURE V4L2_FLASH_FAULT_OVER_TEMPERATURE
> +#define LED_FAULT_SHORT_CIRCUIT V4L2_FLASH_FAULT_SHORT_CIRCUIT
> +#define LED_FAULT_OVER_CURRENT V4L2_FLASH_FAULT_OVER_CURRENT
> +#define LED_FAULT_INDICATOR V4L2_FLASH_FAULT_INDICATOR
> +#define LED_FAULT_UNDER_VOLTAGE V4L2_FLASH_FAULT_UNDER_VOLTAGE
> +#define LED_FAULT_INPUT_VOLTAGE V4L2_FLASH_FAULT_INPUT_VOLTAGE
> +#define LED_FAULT_LED_OVER_TEMPERATURE V4L2_FLASH_OVER_TEMPERATURE
> +
> +struct led_flash_ops {
> + /* set flash brightness */
> + int (*flash_brightness_set)(struct led_classdev_flash *flash,
> + u32 brightness);
> + /* get flash brightness */
> + int (*flash_brightness_get)(struct led_classdev_flash *flash,
> + u32 *brightness);
> + /* set flash indicator brightness */
> + int (*indicator_brightness_set)(struct led_classdev_flash *flash,
> + u32 brightness);
> + /* get flash indicator brightness */
> + int (*indicator_brightness_get)(struct led_classdev_flash *flash,
> + u32 *brightness);
> + /* set flash strobe state */
> + int (*strobe_set)(struct led_classdev_flash *flash, bool state);
> + /* get flash strobe state */
> + int (*strobe_get)(struct led_classdev_flash *flash, bool *state);
> + /* set flash timeout */
> + int (*timeout_set)(struct led_classdev_flash *flash, u32 timeout);
> + /* get the flash LED fault */
> + int (*fault_get)(struct led_classdev_flash *flash, u32 *fault);
> +};
> +
> +/*
> + * Current value of a flash setting along
> + * with its constraints.
> + */
> +struct led_flash_setting {
> + /* maximum allowed value */
> + u32 min;
> + /* maximum allowed value */
> + u32 max;
> + /* step value */
> + u32 step;
> + /* current value */
> + u32 val;
> +};
> +
> +/*
> + * Aggregated flash settings - designed for ease
> + * of passing initialization data to the clients
> + * wrapping a LED Flash class device.
> + */
> +struct led_flash_config {
> + struct led_flash_setting torch_brightness;
> + struct led_flash_setting flash_brightness;
> + struct led_flash_setting indicator_brightness;
> + struct led_flash_setting flash_timeout;
> + u32 flash_faults;
> +};
> +
> +struct led_classdev_flash {
> + /* led class device */
> + struct led_classdev led_cdev;
> +
> + /* flash led specific ops */
> + const struct led_flash_ops *ops;
> +
> + /* flash brightness value in microamperes along with its constraints */
> + struct led_flash_setting brightness;
> +
> + /* timeout value in microseconds along with its constraints */
> + struct led_flash_setting timeout;
> +
> + /*
> + * Indicator brightness value in microamperes along with
> + * its constraints - this is an optional setting and must
> + * be allocated by the driver if the device supports privacy
> + * indicator led.
> + */
> + struct led_flash_setting *indicator_brightness;
> +};
> +
> +static inline struct led_classdev_flash *lcdev_to_flash(
> + struct led_classdev *lcdev)
> +{
> + return container_of(lcdev, struct led_classdev_flash, led_cdev);
> +}
> +
> +/**
> + * led_classdev_flash_register - register a new object of led_classdev class
> + with support for flash LEDs
" *" ...
> + * @parent: the flash LED to register
> + * @flash: the led_classdev_flash structure for this device
> + *
> + * Returns: 0 on success or negative error value on failure
> + */
> +int led_classdev_flash_register(struct device *parent,
> + struct led_classdev_flash *flash);
> +
> +/**
> + * led_classdev_flash_unregister - unregisters an object of led_classdev class
> + with support for flash LEDs
> + * @flash: the flash LED to unregister
> + *
> + * Unregister a previously registered via led_classdev_flash_register object
> + */
> +void led_classdev_flash_unregister(struct led_classdev_flash *flash);
> +
> +/**
> + * led_set_flash_strobe - setup flash strobe
> + * @flash: the flash LED to set strobe on
> + * @state: 1 - strobe flash, 0 - stop flash strobe
> + *
> + * Strobe the flash LED.
> + *
> + * Returns: 0 on success or negative error value on failure
> + */
> +extern int led_set_flash_strobe(struct led_classdev_flash *flash,
> + bool state);
> +
> +/**
> + * led_get_flash_strobe - get flash strobe status
> + * @flash: the flash LED to query
> + * @state: 1 - flash is strobing, 0 - flash is off
> + *
> + * Check whether the flash is strobing at the moment.
> + *
> +u* Returns: 0 on success or negative error value on failure
> + */
> +extern int led_get_flash_strobe(struct led_classdev_flash *flash,
> + bool *state);
I'd put a newline here.
> +/**
> + * led_set_flash_brightness - set flash LED brightness
> + * @flash: the flash LED to set
> + * @brightness: the brightness to set it to
> + *
> + * Set a flash LED's brightness.
> + *
> + * Returns: 0 on success or negative error value on failure
> + */
> +extern int led_set_flash_brightness(struct led_classdev_flash *flash,
> + u32 brightness);
> +
> +/**
> + * led_update_flash_brightness - update flash LED brightness
> + * @flash: the flash LED to query
> + *
> + * Get a flash LED's current brightness and update led_flash->brightness
> + * member with the obtained value.
> + *
> + * Returns: 0 on success or negative error value on failure
> + */
> +extern int led_update_flash_brightness(struct led_classdev_flash *flash);
> +
> +/**
> + * led_set_flash_timeout - set flash LED timeout
> + * @flash: the flash LED to set
> + * @timeout: the flash timeout to set it to
> + *
> + * Set the flash strobe duration. The duration set by the driver
> + * is returned in the timeout argument and may differ from the
> + * one that was originally passed.
> + *
> + * Returns: 0 on success or negative error value on failure
> + */
> +extern int led_set_flash_timeout(struct led_classdev_flash *flash,
> + u32 timeout);
> +
> +/**
> + * led_get_flash_fault - get the flash LED fault
> + * @flash: the flash LED to query
> + * @fault: bitmask containing flash faults
> + *
> + * Get the flash LED fault.
> + *
> + * Returns: 0 on success or negative error value on failure
> + */
> +extern int led_get_flash_fault(struct led_classdev_flash *flash,
> + u32 *fault);
> +
> +/**
> + * led_set_indicator_brightness - set indicator LED brightness
> + * @flash: the flash LED to set
> + * @brightness: the brightness to set it to
> + *
> + * Set an indicator LED's brightness.
> + *
> + * Returns: 0 on success or negative error value on failure
> + */
> +extern int led_set_indicator_brightness(struct led_classdev_flash *flash,
> + u32 led_brightness);
> +
> +/**
> + * led_update_indicator_brightness - update flash indicator LED brightness
> + * @flash: the flash LED to query
> + *
> + * Get a flash indicator LED's current brightness and update
> + * led_flash->indicator_brightness member with the obtained value.
> + *
> + * Returns: 0 on success or negative error value on failure
> + */
> +extern int led_update_indicator_brightness(struct led_classdev_flash *flash);
> +
> +
> +#endif /* __LINUX_FLASH_LEDS_H_INCLUDED */
> diff --git a/include/linux/leds.h b/include/linux/leds.h
> index cfceef3..b9a2797 100644
> --- a/include/linux/leds.h
> +++ b/include/linux/leds.h
> @@ -46,6 +46,8 @@ struct led_classdev {
> #define LED_SYSFS_DISABLE (1 << 20)
> #define SET_BRIGHTNESS_ASYNC (1 << 21)
> #define SET_BRIGHTNESS_SYNC (1 << 22)
> +#define LED_DEV_CAP_FLASH (1 << 23)
> +#define LED_DEV_CAP_INDICATOR (1 << 24)
>
> /* Set LED brightness level */
> /* Must not sleep, use a workqueue if needed */
> @@ -81,6 +83,7 @@ struct led_classdev {
> unsigned long blink_delay_on, blink_delay_off;
> struct timer_list blink_timer;
> int blink_brightness;
> + void (*flash_resume)(struct led_classdev *led_cdev);
>
> struct work_struct set_brightness_work;
> int delayed_set_value;
--
Kind regards,
Sakari Ailus
e-mail: sakari.ailus@iki.fi XMPP: sailus@retiisi.org.uk
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH/RFC v7 2/3] leds: Add LED Flash Class wrapper to LED subsystem
2014-11-27 8:43 ` Sakari Ailus
@ 2014-11-28 9:34 ` Jacek Anaszewski
0 siblings, 0 replies; 9+ messages in thread
From: Jacek Anaszewski @ 2014-11-28 9:34 UTC (permalink / raw)
To: Sakari Ailus
Cc: linux-leds, linux-media, sakari.ailus, kyungmin.park,
b.zolnierkie, Bryan Wu, Richard Purdie
Hi Sakari,
Thanks for the review.
[...]
>> +static void led_clamp_align(struct led_flash_setting *s)
>> +{
>> + u32 v, offset;
>> +
>> + v = s->val + s->step / 2;
>> + v = clamp(v, s->min, s->max);
>> + offset = v - s->min;
>> + offset = s->step * (offset / s->step);
>
> You could use the rounddown() macro. I.e.
>
> rounddown(v - s->min, s->step) + s->min;
I took this code snippet from v4l2-ctrls.c.
It allows for aligning the control value to the nearest
step - top or bottom, whereas rounddown only to the
bottom one.
Best Regards,
Jacek Anaszewski
^ permalink raw reply [flat|nested] 9+ messages in thread
end of thread, other threads:[~2014-11-28 9:34 UTC | newest]
Thread overview: 9+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2014-11-12 16:09 [PATCH/RFC v7 0/3] LED / flash API integration - LED Flash Class Jacek Anaszewski
2014-11-12 16:09 ` [PATCH/RFC v7 1/3] leds: Add support for setting brightness in a synchronous way Jacek Anaszewski
2014-11-13 18:43 ` Bryan Wu
2014-11-12 16:09 ` [PATCH/RFC v7 2/3] leds: Add LED Flash Class wrapper to LED subsystem Jacek Anaszewski
2014-11-27 8:43 ` Sakari Ailus
2014-11-28 9:34 ` Jacek Anaszewski
2014-11-12 16:09 ` [PATCH/RFC v7 3/3] Documentation: leds: Add description of LED Flash Class extension Jacek Anaszewski
2014-11-13 18:58 ` Bryan Wu
2014-11-14 10:21 ` Jacek Anaszewski
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