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    SubjectRe: [PATCH/RFC v10 08/19] leds: Add support for max77693 mfd flash cell
    On Fri 2015-01-09 16:22:58, Jacek Anaszewski wrote:
    > This patch adds led-flash support to Maxim max77693 chipset.
    > A device can be exposed to user space through LED subsystem
    > sysfs interface. Device supports up to two leds which can
    > work in flash and torch mode. The leds can be triggered
    > externally or by software.
    >

    > +struct max77693_sub_led {
    > + /* related FLED output identifier */

    ->flash LED, about 4x.

    > +/* split composite current @i into two @iout according to @imax weights */
    > +static void __max77693_calc_iout(u32 iout[2], u32 i, u32 imax[2])
    > +{
    > + u64 t = i;
    > +
    > + t *= imax[1];
    > + do_div(t, imax[0] + imax[1]);
    > +
    > + iout[1] = (u32)t / FLASH_IOUT_STEP * FLASH_IOUT_STEP;
    > + iout[0] = i - iout[1];
    > +}

    Is 64-bit arithmetics neccessary here? Could we do the FLASH_IOUT_STEP
    divisons before t *=, so that 64-bit division is not neccessary?

    > +static int max77693_led_flash_strobe_get(
    > + struct led_classdev_flash *fled_cdev,
    > + bool *state)
    > +{
    > + struct max77693_sub_led *sub_led = flcdev_to_sub_led(fled_cdev);
    > + struct max77693_led_device *led = sub_led_to_led(sub_led);
    > + int ret;
    > +
    > + if (!state)
    > + return -EINVAL;
    > +
    > + mutex_lock(&led->lock);
    > +
    > + ret = max77693_strobe_status_get(led, state);
    > +
    > + *state = !!(*state && (led->strobing_sub_led_id == sub_led->fled_id));
    > +
    > +
    > + mutex_unlock(&led->lock);
    > +
    > + return ret;
    > +}

    Maybe remove some empty lines?

    --
    (english) http://www.livejournal.com/~pavelmachek
    (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html


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