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Re: [PATCH 3/5] leds: Rename brightness_set_sync op to brightness_set_blocking

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On 09/23/2015 10:36 AM, Jacek Anaszewski wrote:
> On 09/22/2015 08:54 PM, Andrew Lunn wrote:
>> On Wed, Sep 16, 2015 at 12:47:42PM +0200, Jacek Anaszewski wrote:
>>> The initial purpose of brightness_set_sync op, introduced along with
>>> the LED flash class extension, was to add a means for setting torch LED
>>> brightness as soon as possible, which couldn't have been guaranteed by
>>> brightness_set op. This patch renames the op to brightness_set_blocking,
>>> which describes its purpose in a more generic way, and is beneficial
>>> in view of the prospective changes in the core related to using
>>> LED core's set_brightness_work for setting brightness for LED class
>>> drivers that can sleep or use delays while setting 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);
>>> +    /* Can sleep or use delays */
>>> +    int (*brightness_set_blocking)(struct led_classdev *led_cdev,
>>
>> I'm no expert when it comes to flash photography with digital
>> cameras.
>
> This op is now not specific to flash LEDs. The last sentence in the
> commit message explains this, but now I see that it is too long.
> Let's change it to:
>
> "This patch renames the op to brightness_set_blocking,
> which describes its purpose in a more generic way. It is beneficial
> in view of the prospective changes in the LED core, aiming at removing
> the need for using work queues in LED class drivers that can sleep
> or use delays while setting brightness."
>
>> But to me the old comment seems better.
>
> I changed it to highlight the essence of how it differs from
> brightness_set.
>
>> Doesn't the caller
>> want to know the flash is now giving out light?
>
> We have strobe_get op for this, but it is in led-class-flash extension.
> This is irrelevant here.

I focused myself on flash mode of flash LED, but you asked
probably about brightness in torch mode, which can be obtained
with brightness_get op, if implemented by the driver.


-- 
Best Regards,
Jacek Anaszewski
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Re: [PATCH 3/5] leds: Rename brightness_set_sync op to  brightness_set_blocking Andrew Lunn <andrew@lunn.ch> - 2015-09-22 21:10 +0200
  Re: [PATCH 3/5] leds: Rename brightness_set_sync op to  brightness_set_blocking Jacek Anaszewski <j.anaszewski@samsung.com> - 2015-09-23 10:40 +0200
    Re: [PATCH 3/5] leds: Rename brightness_set_sync op to  brightness_set_blocking Jacek Anaszewski <j.anaszewski@samsung.com> - 2015-09-23 11:40 +0200

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