diff options
-rw-r--r-- | drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 81 |
1 files changed, 40 insertions, 41 deletions
diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c index df9338257ae0..4c8a69283698 100644 --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c @@ -2894,51 +2894,50 @@ static int set_backlight_via_aux(struct dc_link *link, uint32_t brightness) return rc ? 0 : 1; } -static u32 convert_brightness(const struct amdgpu_dm_backlight_caps *caps, - const uint32_t user_brightness) +static int get_brightness_range(const struct amdgpu_dm_backlight_caps *caps, + unsigned *min, unsigned *max) { - u32 min, max, conversion_pace; - u32 brightness = user_brightness; - if (!caps) - goto out; + return 0; - if (!caps->aux_support) { - max = caps->max_input_signal; - min = caps->min_input_signal; - /* - * The brightness input is in the range 0-255 - * It needs to be rescaled to be between the - * requested min and max input signal - * It also needs to be scaled up by 0x101 to - * match the DC interface which has a range of - * 0 to 0xffff - */ - conversion_pace = 0x101; - brightness = - user_brightness - * conversion_pace - * (max - min) - / AMDGPU_MAX_BL_LEVEL - + min * conversion_pace; + if (caps->aux_support) { + // Firmware limits are in nits, DC API wants millinits. + *max = 1000 * caps->aux_max_input_signal; + *min = 1000 * caps->aux_min_input_signal; } else { - /* TODO - * We are doing a linear interpolation here, which is OK but - * does not provide the optimal result. We probably want - * something close to the Perceptual Quantizer (PQ) curve. - */ - max = caps->aux_max_input_signal; - min = caps->aux_min_input_signal; - - brightness = (AMDGPU_MAX_BL_LEVEL - user_brightness) * min - + user_brightness * max; - // Multiple the value by 1000 since we use millinits - brightness *= 1000; - brightness = DIV_ROUND_CLOSEST(brightness, AMDGPU_MAX_BL_LEVEL); + // Firmware limits are 8-bit, PWM control is 16-bit. + *max = 0x101 * caps->max_input_signal; + *min = 0x101 * caps->min_input_signal; } + return 1; +} + +static u32 convert_brightness_from_user(const struct amdgpu_dm_backlight_caps *caps, + uint32_t brightness) +{ + unsigned min, max; -out: - return brightness; + if (!get_brightness_range(caps, &min, &max)) + return brightness; + + // Rescale 0..255 to min..max + return min + DIV_ROUND_CLOSEST((max - min) * brightness, + AMDGPU_MAX_BL_LEVEL); +} + +static u32 convert_brightness_to_user(const struct amdgpu_dm_backlight_caps *caps, + uint32_t brightness) +{ + unsigned min, max; + + if (!get_brightness_range(caps, &min, &max)) + return brightness; + + if (brightness < min) + return 0; + // Rescale min..max to 0..255 + return DIV_ROUND_CLOSEST(AMDGPU_MAX_BL_LEVEL * (brightness - min), + max - min); } static int amdgpu_dm_backlight_update_status(struct backlight_device *bd) @@ -2954,7 +2953,7 @@ static int amdgpu_dm_backlight_update_status(struct backlight_device *bd) link = (struct dc_link *)dm->backlight_link; - brightness = convert_brightness(&caps, bd->props.brightness); + brightness = convert_brightness_from_user(&caps, bd->props.brightness); // Change brightness based on AUX property if (caps.aux_support) return set_backlight_via_aux(link, brightness); @@ -2971,7 +2970,7 @@ static int amdgpu_dm_backlight_get_brightness(struct backlight_device *bd) if (ret == DC_ERROR_UNEXPECTED) return bd->props.brightness; - return ret; + return convert_brightness_to_user(&dm->backlight_caps, ret); } static const struct backlight_ops amdgpu_dm_backlight_ops = { |