The patch titled
led-class-always-implement-blinking-update
has been added to the -mm tree. Its filename is
led-class-always-implement-blinking-update.patch
Before you just go and hit "reply", please:
a) Consider who else should be cc'ed
b) Prefer to cc a suitable mailing list as well
c) Ideally: find the original patch on the mailing list and do a
reply-to-all to that, adding suitable additional cc's
*** Remember to use Documentation/SubmitChecklist when testing your code ***
See http://userweb.kernel.org/~akpm/stuff/added-to-mm.txt to find
out what to do about this
The current -mm tree may be found at http://userweb.kernel.org/~akpm/mmotm/
------------------------------------------------------
Subject: led-class-always-implement-blinking-update
From: Johannes Berg <johannes.berg@xxxxxxxxx>
v2: - update documentation
- use documented way of turning blinking off
by setting brightness to 0 rather than by
setting delays to (0, 0)
- add API to start blinking, set brightness
(the latter will also stop sw blinking)
v3: - make LEDS_CLASS a bool rather than tristate
because LEDS_TRIGGERS now depends on symbols
it exports
Signed-off-by: Johannes Berg <johannes.berg@xxxxxxxxx>
Cc: Richard Purdie <rpurdie@xxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
Documentation/leds-class.txt | 21 +++++-----
drivers/leds/Kconfig | 2
drivers/leds/led-class.c | 69 ++++++++++++++++++++++-----------
drivers/leds/led-triggers.c | 4 -
drivers/leds/ledtrig-timer.c | 10 +---
include/linux/leds.h | 42 ++++++++++++++++++--
6 files changed, 102 insertions(+), 46 deletions(-)
diff -puN Documentation/leds-class.txt~led-class-always-implement-blinking-update Documentation/leds-class.txt
--- a/Documentation/leds-class.txt~led-class-always-implement-blinking-update
+++ a/Documentation/leds-class.txt
@@ -57,15 +57,18 @@ Hardware accelerated blink of LEDs
Some LEDs can be programmed to blink without any CPU interaction. To
support this feature, a LED driver can optionally implement the
-blink_set() function (see <linux/leds.h>). If implemented, triggers can
-attempt to use it before falling back to software timers. The blink_set()
-function should return 0 if the blink setting is supported, or -EINVAL
-otherwise, which means that LED blinking will be handled by software.
-
-The blink_set() function should choose a user friendly blinking
-value if it is called with *delay_on==0 && *delay_off==0 parameters. In
-this case the driver should give back the chosen value through delay_on
-and delay_off parameters to the leds subsystem.
+blink_set() function (see <linux/leds.h>). To set an LED to blinking,
+however, it is better to use use the API function led_blink_set(),
+as it will check and implement software fallback if necessary.
+
+To turn off blinking again, use the API function led_brightness_set()
+as that will not just set the LED brightness but also stop any software
+timers that may have been required for blinking.
+
+The blink_set() function should choose a user friendly blinking value
+if it is called with *delay_on==0 && *delay_off==0 parameters. In this
+case the driver should give back the chosen value through delay_on and
+delay_off parameters to the leds subsystem.
Setting the brightness to zero with brightness_set() callback function
should completely turn off the LED and cancel the previously programmed
diff -puN drivers/leds/Kconfig~led-class-always-implement-blinking-update drivers/leds/Kconfig
--- a/drivers/leds/Kconfig~led-class-always-implement-blinking-update
+++ a/drivers/leds/Kconfig
@@ -7,7 +7,7 @@ menuconfig NEW_LEDS
if NEW_LEDS
config LEDS_CLASS
- tristate "LED Class Support"
+ bool "LED Class Support"
help
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.
diff -puN drivers/leds/led-class.c~led-class-always-implement-blinking-update drivers/leds/led-class.c
--- a/drivers/leds/led-class.c~led-class-always-implement-blinking-update
+++ a/drivers/leds/led-class.c
@@ -111,8 +111,17 @@ static void led_timer_function(unsigned
mod_timer(&led_cdev->blink_timer, jiffies + msecs_to_jiffies(delay));
}
-static int led_blink_set(struct led_classdev *led_cdev,
- unsigned long *delay_on, unsigned long *delay_off)
+static void led_stop_software_blink(struct led_classdev *led_cdev)
+{
+ /* deactivate previous settings */
+ del_timer_sync(&led_cdev->blink_timer);
+ led_cdev->blink_delay_on = 0;
+ led_cdev->blink_delay_off = 0;
+}
+
+static void led_set_software_blink(struct led_classdev *led_cdev,
+ unsigned long delay_on,
+ unsigned long delay_off)
{
int current_brightness;
@@ -122,29 +131,26 @@ static int led_blink_set(struct led_clas
if (!led_cdev->blink_brightness)
led_cdev->blink_brightness = led_cdev->max_brightness;
- if (*delay_on == led_cdev->blink_delay_on &&
- *delay_off == led_cdev->blink_delay_off)
- return 0;
+ if (delay_on == led_cdev->blink_delay_on &&
+ delay_off == led_cdev->blink_delay_off)
+ return;
- /* deactivate previous settings */
- del_timer_sync(&led_cdev->blink_timer);
+ led_stop_software_blink(led_cdev);
- led_cdev->blink_delay_on = *delay_on;
- led_cdev->blink_delay_off = *delay_off;
+ led_cdev->blink_delay_on = delay_on;
+ led_cdev->blink_delay_off = delay_off;
/* never on - don't blink */
- if (!*delay_on)
- return 0;
+ if (!delay_on)
+ return;
/* never off - just set to brightness */
- if (!*delay_off) {
+ if (!delay_off) {
led_set_brightness(led_cdev, led_cdev->blink_brightness);
- return 0;
+ return;
}
mod_timer(&led_cdev->blink_timer, jiffies + 1);
-
- return 0;
}
@@ -219,9 +225,6 @@ int led_classdev_register(struct device
led_cdev->blink_timer.function = led_timer_function;
led_cdev->blink_timer.data = (unsigned long)led_cdev;
- if (!led_cdev->blink_set)
- led_cdev->blink_set = led_blink_set;
-
#ifdef CONFIG_LEDS_TRIGGERS
led_trigger_set_default(led_cdev);
#endif
@@ -231,7 +234,6 @@ int led_classdev_register(struct device
return 0;
}
-
EXPORT_SYMBOL_GPL(led_classdev_register);
/**
@@ -242,8 +244,6 @@ EXPORT_SYMBOL_GPL(led_classdev_register)
*/
void led_classdev_unregister(struct led_classdev *led_cdev)
{
- unsigned long on = 0, off = 0;
-
#ifdef CONFIG_LEDS_TRIGGERS
down_write(&led_cdev->trigger_lock);
if (led_cdev->trigger)
@@ -251,7 +251,8 @@ void led_classdev_unregister(struct led_
up_write(&led_cdev->trigger_lock);
#endif
- led_cdev->blink_set(led_cdev, &on, &off);
+ /* Stop blinking */
+ led_brightness_set(led_cdev, LED_OFF);
device_unregister(led_cdev->dev);
@@ -261,6 +262,30 @@ void led_classdev_unregister(struct led_
}
EXPORT_SYMBOL_GPL(led_classdev_unregister);
+void led_blink_set(struct led_classdev *led_cdev,
+ unsigned long *delay_on,
+ unsigned long *delay_off)
+{
+ if (led_cdev->blink_set &&
+ led_cdev->blink_set(led_cdev, delay_on, delay_off))
+ return;
+
+ /* blink with 1 Hz as default if nothing specified */
+ if (!*delay_on && !*delay_off)
+ *delay_on = *delay_off = 500;
+
+ led_set_software_blink(led_cdev, *delay_on, *delay_off);
+}
+EXPORT_SYMBOL(led_blink_set);
+
+void led_brightness_set(struct led_classdev *led_cdev,
+ enum led_brightness brightness)
+{
+ led_stop_software_blink(led_cdev);
+ led_cdev->brightness_set(led_cdev, brightness);
+}
+EXPORT_SYMBOL(led_brightness_set);
+
static int __init leds_init(void)
{
leds_class = class_create(THIS_MODULE, "leds");
diff -puN drivers/leds/led-triggers.c~led-class-always-implement-blinking-update drivers/leds/led-triggers.c
--- a/drivers/leds/led-triggers.c~led-class-always-implement-blinking-update
+++ a/drivers/leds/led-triggers.c
@@ -103,7 +103,6 @@ EXPORT_SYMBOL_GPL(led_trigger_show);
void led_trigger_set(struct led_classdev *led_cdev, struct led_trigger *trigger)
{
unsigned long flags;
- unsigned long on = 0, off = 0;
/* Remove any existing trigger */
if (led_cdev->trigger) {
@@ -114,8 +113,7 @@ void led_trigger_set(struct led_classdev
if (led_cdev->trigger->deactivate)
led_cdev->trigger->deactivate(led_cdev);
led_cdev->trigger = NULL;
- led_cdev->blink_set(led_cdev, &on, &off);
- led_set_brightness(led_cdev, LED_OFF);
+ led_brightness_set(led_cdev, LED_OFF);
}
if (trigger) {
write_lock_irqsave(&trigger->leddev_list_lock, flags);
diff -puN drivers/leds/ledtrig-timer.c~led-class-always-implement-blinking-update drivers/leds/ledtrig-timer.c
--- a/drivers/leds/ledtrig-timer.c~led-class-always-implement-blinking-update
+++ a/drivers/leds/ledtrig-timer.c
@@ -40,8 +40,7 @@ static ssize_t led_delay_on_store(struct
count++;
if (count == size) {
- led_cdev->blink_set(led_cdev, &state,
- &led_cdev->blink_delay_off);
+ led_blink_set(led_cdev, &state, &led_cdev->blink_delay_off);
ret = count;
}
@@ -69,8 +68,7 @@ static ssize_t led_delay_off_store(struc
count++;
if (count == size) {
- led_cdev->blink_set(led_cdev, &led_cdev->blink_delay_on,
- &state);
+ led_blink_set(led_cdev, &led_cdev->blink_delay_on, &state);
ret = count;
}
@@ -103,15 +101,13 @@ err_out_delayon:
static void timer_trig_deactivate(struct led_classdev *led_cdev)
{
- unsigned long on = 0, off = 0;
-
if (led_cdev->trigger_data) {
device_remove_file(led_cdev->dev, &dev_attr_delay_on);
device_remove_file(led_cdev->dev, &dev_attr_delay_off);
}
/* Stop blinking */
- led_cdev->blink_set(led_cdev, &on, &off);
+ led_brightness_set(led_cdev, LED_OFF);
}
static struct led_trigger timer_led_trigger = {
diff -puN include/linux/leds.h~led-class-always-implement-blinking-update include/linux/leds.h
--- a/include/linux/leds.h~led-class-always-implement-blinking-update
+++ a/include/linux/leds.h
@@ -46,10 +46,14 @@ struct led_classdev {
/* Get LED brightness level */
enum led_brightness (*brightness_get)(struct led_classdev *led_cdev);
- /* Activate hardware accelerated blink, delays are in
- * miliseconds and if none is provided then a sensible default
- * should be chosen. The call can adjust the timings if it can't
- * match the values specified exactly. */
+ /*
+ * Activate hardware accelerated blink, delays are in milliseconds
+ * and if both are zero then a sensible default should be chosen.
+ * The call should adjust the timings in that case and if it can't
+ * match the values specified exactly.
+ * Deactivate blinking again when the brightness is set to a fixed
+ * value via the brightness_set() callback.
+ */
int (*blink_set)(struct led_classdev *led_cdev,
unsigned long *delay_on,
unsigned long *delay_off);
@@ -78,6 +82,36 @@ extern void led_classdev_unregister(stru
extern void led_classdev_suspend(struct led_classdev *led_cdev);
extern void led_classdev_resume(struct led_classdev *led_cdev);
+/**
+ * led_blink_set - set blinking with software fallback
+ * @led_cdev: the LED to start blinking
+ * @delay_on: the time it should be on (in ms)
+ * @delay_off: the time it should ble off (in ms)
+ *
+ * This function makes the LED blink, attempting to use the
+ * hardware acceleration if possible, but falling back to
+ * software blinking if there is no hardware blinking or if
+ * the LED refuses the passed values.
+ *
+ * Note that if software blinking is active, simply calling
+ * led_cdev->brightness_set() will not stop the blinking,
+ * use led_classdev_brightness_set() instead.
+ */
+extern void led_blink_set(struct led_classdev *led_cdev,
+ unsigned long *delay_on,
+ unsigned long *delay_off);
+/**
+ * led_brightness_set - set LED brightness
+ * @led_cdev: the LED to set
+ * @brightness: the brightness to set it to
+ *
+ * Set an LED's brightness, and, if necessary, cancel the
+ * software blink timer that implements blinking when the
+ * hardware doesn't.
+ */
+extern void led_brightness_set(struct led_classdev *led_cdev,
+ enum led_brightness brightness);
+
/*
* LED Triggers
*/
_
Patches currently in -mm which might be from johannes.berg@xxxxxxxxx are
linux-next.patch
led-class-always-implement-blinking.patch
led-class-always-implement-blinking-update.patch
--
To unsubscribe from this list: send the line "unsubscribe mm-commits" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
