diff options
Diffstat (limited to 'drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c')
| -rw-r--r-- | drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 59 |
1 files changed, 47 insertions, 12 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 1ed079a6ca81..a5ba1d6990cc 100644 --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c @@ -1589,27 +1589,60 @@ static int amdgpu_dm_mode_config_init(struct amdgpu_device *adev) return 0; } +#define AMDGPU_DM_DEFAULT_MIN_BACKLIGHT 12 +#define AMDGPU_DM_DEFAULT_MAX_BACKLIGHT 255 + #if defined(CONFIG_BACKLIGHT_CLASS_DEVICE) ||\ defined(CONFIG_BACKLIGHT_CLASS_DEVICE_MODULE) +static void amdgpu_dm_update_backlight_caps(struct amdgpu_display_manager *dm) +{ +#if defined(CONFIG_ACPI) + struct amdgpu_dm_backlight_caps caps; + + if (dm->backlight_caps.caps_valid) + return; + + amdgpu_acpi_get_backlight_caps(dm->adev, &caps); + if (caps.caps_valid) { + dm->backlight_caps.min_input_signal = caps.min_input_signal; + dm->backlight_caps.max_input_signal = caps.max_input_signal; + dm->backlight_caps.caps_valid = true; + } else { + dm->backlight_caps.min_input_signal = + AMDGPU_DM_DEFAULT_MIN_BACKLIGHT; + dm->backlight_caps.max_input_signal = + AMDGPU_DM_DEFAULT_MAX_BACKLIGHT; + } +#else + dm->backlight_min_input_signal = AMDGPU_DM_DEFAULT_MIN_BACKLIGHT; + dm->backlight_max_input_signal = AMDGPU_DM_DEFAULT_MAX_BACKLIGHT; +#endif +} + static int amdgpu_dm_backlight_update_status(struct backlight_device *bd) { struct amdgpu_display_manager *dm = bl_get_data(bd); + struct amdgpu_dm_backlight_caps caps; + uint32_t brightness = bd->props.brightness; - /* backlight_pwm_u16_16 parameter is in unsigned 32 bit, 16 bit integer - * and 16 bit fractional, where 1.0 is max backlight value. - * bd->props.brightness is 8 bit format and needs to be converted by - * scaling via copy lower byte to upper byte of 16 bit value. - */ - uint32_t brightness = bd->props.brightness * 0x101; - + amdgpu_dm_update_backlight_caps(dm); + caps = dm->backlight_caps; /* - * PWM interperts 0 as 100% rather than 0% because of HW - * limitation for level 0. So limiting minimum brightness level - * to 1. + * 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 */ - if (bd->props.brightness < 1) - brightness = 0x101; + brightness = + brightness + * 0x101 + * (caps.max_input_signal - caps.min_input_signal) + / AMDGPU_MAX_BL_LEVEL + + caps.min_input_signal * 0x101; if (dc_link_set_backlight_level(dm->backlight_link, brightness, 0, 0)) @@ -1639,6 +1672,8 @@ amdgpu_dm_register_backlight_device(struct amdgpu_display_manager *dm) char bl_name[16]; struct backlight_properties props = { 0 }; + amdgpu_dm_update_backlight_caps(dm); + props.max_brightness = AMDGPU_MAX_BL_LEVEL; props.brightness = AMDGPU_MAX_BL_LEVEL; props.type = BACKLIGHT_RAW; |