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?
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