Hi Jacek, On 10 October 2018 at 02:37, Jacek Anaszewski <jacek.anaszewski@xxxxxxxxx> wrote: > Hi Baolin, > > On 10/09/2018 02:01 PM, Baolin Wang wrote: >> Hi Jacek and Pavel, >> >> On 5 October 2018 at 04:00, Jacek Anaszewski <jacek.anaszewski@xxxxxxxxx> wrote: >>> Hi Baolin, >>> >>> On 10/03/2018 03:21 AM, Baolin Wang wrote: >>>> Hi Jacek, >>>> >>>> On 3 October 2018 at 04:25, Jacek Anaszewski <jacek.anaszewski@xxxxxxxxx> wrote: >>>>> Hi Baolin, >>>>> >>>>> Thank you for the v14. We'll probably need v15, though :-) >>>>> >>>>> I added the comments in the code below. >>>>> >>>>> On 10/02/2018 05:43 PM, Baolin Wang wrote: >>>>>> This patch adds one new led trigger that LED device can configure >>>>>> the software or hardware pattern and trigger it. >>>>>> >>>>>> Consumers can write 'pattern' file to enable the software pattern >>>>>> which alters the brightness for the specified duration with one >>>>>> software timer. >>>>>> >>>>>> Moreover consumers can write 'hw_pattern' file to enable the hardware >>>>>> pattern for some LED controllers which can autonomously control >>>>>> brightness over time, according to some preprogrammed hardware >>>>>> patterns. >>>>>> >>>>>> Signed-off-by: Raphael Teysseyre <rteysseyre@xxxxxxxxx> >>>>>> Signed-off-by: Baolin Wang <baolin.wang@xxxxxxxxxx> >>>>>> --- >>>>>> Changes from v13: >>>>>> - Add duration validation for gradual dimming. >>>>>> - Coding style optimization. >>>>>> >>>>>> Changes from v12: >>>>>> - Add gradual dimming support for software pattern. >>>>>> >>>>>> Changes from v11: >>>>>> - Change -1 means repeat indefinitely. >>>>>> >>>>>> Changes from v10: >>>>>> - Change 'int' to 'u32' for delta_t field. >>>>>> >>>>>> Changes from v9: >>>>>> - None. >>>>>> >>>>>> Changes from v8: >>>>>> - None. >>>>>> >>>>>> Changes from v7: >>>>>> - Move the SC27XX hardware patterns description into its own ABI file. >>>>>> >>>>>> Changes from v6: >>>>>> - Improve commit message. >>>>>> - Optimize the description of the hw_pattern file. >>>>>> - Simplify some logics. >>>>>> >>>>>> Changes from v5: >>>>>> - Add one 'hw_pattern' file for hardware patterns. >>>>>> >>>>>> Changes from v4: >>>>>> - Change the repeat file to return the originally written number. >>>>>> - Improve comments. >>>>>> - Fix some build warnings. >>>>>> >>>>>> Changes from v3: >>>>>> - Reset pattern number to 0 if user provides incorrect pattern string. >>>>>> - Support one pattern. >>>>>> >>>>>> Changes from v2: >>>>>> - Remove hardware_pattern boolen. >>>>>> - Chnage the pattern string format. >>>>>> >>>>>> Changes from v1: >>>>>> - Use ATTRIBUTE_GROUPS() to define attributes. >>>>>> - Introduce hardware_pattern flag to determine if software pattern >>>>>> or hardware pattern. >>>>>> - Re-implement pattern_trig_store_pattern() function. >>>>>> - Remove pattern_get() interface. >>>>>> - Improve comments. >>>>>> - Other small optimization. >>>>>> --- >>>>>> .../ABI/testing/sysfs-class-led-trigger-pattern | 76 ++++ >>>>>> drivers/leds/trigger/Kconfig | 7 + >>>>>> drivers/leds/trigger/Makefile | 1 + >>>>>> drivers/leds/trigger/ledtrig-pattern.c | 431 +++++++++++++++++++++ >>>>>> include/linux/leds.h | 15 + >>>>>> 5 files changed, 530 insertions(+) >>>>>> create mode 100644 Documentation/ABI/testing/sysfs-class-led-trigger-pattern >>>>>> create mode 100644 drivers/leds/trigger/ledtrig-pattern.c >>>>>> >>>>>> diff --git a/Documentation/ABI/testing/sysfs-class-led-trigger-pattern b/Documentation/ABI/testing/sysfs-class-led-trigger-pattern >>>>>> new file mode 100644 >>>>>> index 0000000..22d7af7 >>>>>> --- /dev/null >>>>>> +++ b/Documentation/ABI/testing/sysfs-class-led-trigger-pattern >>>>>> @@ -0,0 +1,76 @@ >>>>>> +What: /sys/class/leds/<led>/pattern >>>>>> +Date: September 2018 >>>>>> +KernelVersion: 4.20 >>>>>> +Description: >>>>>> + Specify a software pattern for the LED, that supports altering >>>>>> + the brightness for the specified duration with one software >>>>>> + timer. It can do gradual dimming and constant brightness. >>>>>> + >>>>>> + The pattern is given by a series of tuples, of brightness and >>>>>> + duration (ms). The LED is expected to traverse the series and >>>>>> + each brightness value for the specified duration. Duration of >>>>>> + 0 means brightness should immediately change to new value. >>>>>> + >>>>>> + 1. When doing gradual dimming, the led brightness will be updated >>>>>> + every 50 milliseconds, so the duration of each step should not >>>>>> + less than 50 milliseconds. >>>>> >>>>> I'd like to avoid this constraint. Lowest supported delta_t should be 1. >>>>> >>>>> We should only prevent entering dimming mode if current delta_t >>>>> is lower than UPDATE_INTERVAL. >>>> >>>> I do not think so. If the pattern format is used for dimming and the >>>> delta_t is lower than UPDATE_INTERVAL, we should return errors. Since >>>> in this case, we can not change to constant mode. >>> >>> I'll play with the code at weekend and will let you know my findings. >> >> Thanks Jacek. Do you have any more suggestion? > > Sorry to say, but I had really busy weekend and failed to carve out > time for looking into that. It's queued up with the highest priority > on my todo list of things needing more than five minutes of attention. Ah, okay, no hurry :) >> BTW, we have not get a consensus about adding one 'dimming_interval' >> file to set the dimming interval instead of fixed 50 ms. >> Pavel, I want to hear your suggestion before I submit new patch set? Thanks. > > I think that this feature belongs to the "nice to have" category, > and lack of it will not prevent us from merging the patch set. OK. Thanks. -- Baolin Wang Best Regards