Commit Graph

2 Commits

Author SHA1 Message Date
Marek Behún 065d099f1b leds: multicolor: Use rounded division when calculating color components
Given channel intensity, LED brightness and max LED brightness, the
multicolor LED framework helper led_mc_calc_color_components() computes
the color channel brightness as

    chan_brightness = brightness * chan_intensity / max_brightness

Consider the situation when (brightness, intensity, max_brightness) is
for example (16, 15, 255), then chan_brightness is computed to 0
although the fractional divison would give 0.94, which should be rounded
to 1.

Use DIV_ROUND_CLOSEST here for the division to give more realistic
component computation:

    chan_brightness = DIV_ROUND_CLOSEST(brightness * chan_intensity,
                                        max_brightness)

Fixes: 55d5d3b46b ("leds: multicolor: Introduce a multicolor class definition")
Signed-off-by: Marek Behún <kabel@kernel.org>
Link: https://lore.kernel.org/r/20230801124931.8661-1-kabel@kernel.org
Signed-off-by: Lee Jones <lee@kernel.org>
2023-08-17 11:25:03 +01:00
Dan Murphy 55d5d3b46b leds: multicolor: Introduce a multicolor class definition
Introduce a multicolor class that groups colored LEDs
within a LED node.

The multicolor class groups monochrome LEDs and allows controlling two
aspects of the final combined color: hue and lightness. The former is
controlled via the intensity file and the latter is controlled
via brightness file.

Signed-off-by: Dan Murphy <dmurphy@ti.com>
Acked-by: Jacek Anaszewski <jacek.anaszewski@gmail.com>
Signed-off-by: Pavel Machek <pavel@ucw.cz>
[squashed leds: multicolor: Fix camel case in documentation in]
2020-07-22 14:41:29 +02:00