backlight: pwm_bl: Set scale type for CIE 1931 curves (511a2046) · Commits · 戴 / test

For backlight curves calculated with the CIE 1931 algorithm set the brightness scale type to non-linear. This makes the scale type available to userspace via the 'scale' sysfs attribute. Signed-off-by:

Matthias Kaehlcke <mka@chromium.org> Tested-by:

Enric Balletbo i Serra <enric.balletbo@collabora.com> Acked-by:

Daniel Thompson <daniel.thompson@linaro.org> Signed-off-by:

Lee Jones <lee.jones@linaro.org>

drivers/video/backlight/pwm_bl.c

+4 −1

Original line number	Diff line number	Diff line
		@@ -536,6 +536,8 @@ static int pwm_backlight_probe(struct platform_device *pdev)
		goto err_alloc;
		}

		memset(&props, 0, sizeof(struct backlight_properties));

		if (data->levels) {
		/*
		* For the DT case, only when brightness levels is defined
		@@ -574,6 +576,8 @@ static int pwm_backlight_probe(struct platform_device *pdev)

		pb->levels = data->levels;
		}

		props.scale = BACKLIGHT_SCALE_NON_LINEAR;
		} else {
		/*
		* That only happens for the non-DT case, where platform data
		@@ -584,7 +588,6 @@ static int pwm_backlight_probe(struct platform_device *pdev)

		pb->lth_brightness = data->lth_brightness * (state.period / pb->scale);

		memset(&props, 0, sizeof(struct backlight_properties));
		props.type = BACKLIGHT_RAW;
		props.max_brightness = data->max_brightness;
		bl = backlight_device_register(dev_name(&pdev->dev), &pdev->dev, pb,

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