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authorLinus Torvalds <torvalds@linux-foundation.org>2016-01-12 07:40:48 +0300
committerLinus Torvalds <torvalds@linux-foundation.org>2016-01-12 07:40:48 +0300
commit2c487121e3c4f87e82cff493872675bde52e47fc (patch)
treec32f72d674c3503cff63063804de6b4e990d9545 /Documentation
parentd870a9d5e31ea69a1ceb7555d0d79364c442c5c0 (diff)
parent522f17e1214cf112e62cff56150964d8b68b94b2 (diff)
downloadlinux-2c487121e3c4f87e82cff493872675bde52e47fc.tar.xz
Merge tag 'leds-for-4.5' of git://git.kernel.org/pub/scm/linux/kernel/git/j.anaszewski/linux-leds
Pull LED subsystem updates from Jacek Anaszewski: "Besides regular driver updates, we introduce a portion of LED core improvements, that allow to avoid the need for using work queues in the LED class drivers, that set brightness in a blocking way. Affected LED class drivers are being optimized accordingly. - LED core improvements: - use EXPORT_SYMBOL_GPL consistently, - add two new LED_BLINK_ flags, - rename brightness_set_sync op to brightness_set_blocking, - add led_set_brightness_nosleep{nopm} functions, - use set_brightness_work for the blocking op, - drivers shouldn't enforce SYNC/ASYNC brightness setting, - turn off the LED and wait for completion on unregistering LED class device, - add managed version of led_trigger_register, - add description of brightness setting API to the LED class doc. - Remove work queues from drivers: leds-tlc591xx, leds-88pm860x, leds-adp5520, leds-bd2802, leds-blinkm, leds-lm3533, leds-lm3642, leds-pca9532, leds-lp3944, leds-lp55xx, leds-lp8788, leds-lp8860, leds-pca955x, leds-pca963x, leds-wm831x, leds-da903x, leds-da9052, leds-dac124d085, leds-lt3593, leds-max8997, leds-mc13783, leds-regulator, leds-wm8350, leds-max77693, leds-aat1290, leds-ktd2692, leds-gpio, leds-pwm, leds-lm355x, leds-ns2. - Replace brightness_set op with a new brightness_set_blocking op to make the drivers compatible with led triggers: leds-ipaq-micro, leds-powernv. - Add missing of_node_put: leds-ktd2692, leds-aat1290, leds-max77693. - Make the driver explicitly non-modular: ledtrig-cpu, ledtrig-ide-disk, leds-syscon. - Improvements to leds-bcm6328: - reuse bcm6328_led_set() instead of copying its functionality, - swap LED ON and OFF definitions, - improve blink support, - simplify duplicated unlock in bcm6328_blink_set, - add little endian support, - remove unneded lock when checking initial LED status, - add HAS_IOMEM dependency, - code cleaning. - Improvements to leds-bcm6358: - use bcm6358_led_set() in order to get rid of the lock, - merge bcm6358_led_mode and bcm6358_led_set, - add little endian support, - remove unneded lock when checking initial LED status, - add HAS_IOMEM dependency, - remove unneeded busy status check. - Call led_pwm_set() in leds-pwm to enforce default LED_OFF. - Fix duration to be msec instead of jiffies: ledtrig-transient. - Removing NULL check: leds-powernv. - Use platform_register/unregister_drivers(): leds-sunfire. - Fix module license specification: ledtrig-oneshot. - Fix driver description and make license match the header: leds-pwm. - Remove checking for state < 1 in flash_strobe_store(): led-class-flash. - Use led_set_brightness_sync for torch brightness: v4l2-flash-led-class" * tag 'leds-for-4.5' of git://git.kernel.org/pub/scm/linux/kernel/git/j.anaszewski/linux-leds: (68 commits) leds: add HAS_IOMEM dependency to LEDS_BCM6328/LEDS_BCM6358 leds: core: add managed version of led_trigger_register leds: bcm6358: remove unneeded busy status check leds: bcm6328: improve blink support leds: bcm6358: merge bcm6358_led_mode and bcm6358_led_set leds: bcm6328: simplify duplicated unlock in bcm6328_blink_set leds: bcm6358: add little endian support leds: bcm6328: add little endian support leds: bcm6358: remove unneded lock when checking initial LED status leds: bcm6358: Use bcm6358_led_set() in order to get rid of the lock leds: bcm6328: remove unneded lock when checking initial LED leds: bcm6328: code cleaning leds: syscon: Make the driver explicitly non-modular leds: ledtrig-ide-disk: Make the driver explicitly non-modular leds: ledtrig-cpu: Make the driver explicitly non-modular leds: sunfire: Use platform_register/unregister_drivers() leds: max77693: Add missing of_node_put leds: aat1290: Add missing of_node_put leds: powernv: Implement brightness_set_blocking op leds: ipaq-micro: Implement brightness_set_blocking op ...
Diffstat (limited to 'Documentation')
-rw-r--r--Documentation/leds/leds-class.txt13
1 files changed, 13 insertions, 0 deletions
diff --git a/Documentation/leds/leds-class.txt b/Documentation/leds/leds-class.txt
index 62261c04060a..d406d98339b2 100644
--- a/Documentation/leds/leds-class.txt
+++ b/Documentation/leds/leds-class.txt
@@ -52,6 +52,19 @@ above leaves scope for further attributes should they be needed. If sections
of the name don't apply, just leave that section blank.
+Brightness setting API
+======================
+
+LED subsystem core exposes following API for setting brightness:
+
+ - led_set_brightness : it is guaranteed not to sleep, passing LED_OFF stops
+ blinking,
+ - led_set_brightness_sync : for use cases when immediate effect is desired -
+ it can block the caller for the time required for accessing
+ device registers and can sleep, passing LED_OFF stops hardware
+ blinking, returns -EBUSY if software blink fallback is enabled.
+
+
Hardware accelerated blink of LEDs
==================================