From 2e38178e23e63b193654af9a11bb4a3cb4b999a5 Mon Sep 17 00:00:00 2001 From: Daniel Vetter Date: Wed, 12 Apr 2017 17:20:06 +0200 Subject: [PATCH] drm/doc: Interlink color manager docs better Git-commit: 2e38178e23e63b193654af9a11bb4a3cb4b999a5 Patch-mainline: v4.13-rc1 References: FATE#322643 bsc#1055900 Motivated by a request from Eric. V2: Take in suggestions from Lionel Cc: Eric Anholt Cc: Lionel Landwerlin Reviewed-by: Lionel Landwerlin Signed-off-by: Daniel Vetter Link: http://patchwork.freedesktop.org/patch/msgid/20170412152006.12233-1-daniel.vetter@ffwll.ch Acked-by: Takashi Iwai --- drivers/gpu/drm/drm_atomic_helper.c | 3 ++- drivers/gpu/drm/drm_color_mgmt.c | 9 ++++++--- include/drm/drm_crtc.h | 34 ++++++++++++++++++++++++++++------ 3 files changed, 36 insertions(+), 10 deletions(-) --- a/drivers/gpu/drm/drm_atomic_helper.c +++ b/drivers/gpu/drm/drm_atomic_helper.c @@ -3528,7 +3528,8 @@ EXPORT_SYMBOL(drm_atomic_helper_connecto * * Implements support for legacy gamma correction table for drivers * that support color management through the DEGAMMA_LUT/GAMMA_LUT - * properties. + * properties. See drm_crtc_enable_color_mgmt() and the containing chapter for + * how the atomic color management and gamma tables work. */ int drm_atomic_helper_legacy_gamma_set(struct drm_crtc *crtc, u16 *red, u16 *green, u16 *blue, --- a/drivers/gpu/drm/drm_color_mgmt.c +++ b/drivers/gpu/drm/drm_color_mgmt.c @@ -43,7 +43,8 @@ * * Setting this to NULL (blob property value set to 0) means a * linear/pass-thru gamma table should be used. This is generally the - * driver boot-up state too. + * driver boot-up state too. Drivers can access this blob through + * &drm_crtc_state.degamma_lut. * * “DEGAMMA_LUT_SIZE”: * Unsinged range property to give the size of the lookup table to be set @@ -60,7 +61,8 @@ * * Setting this to NULL (blob property value set to 0) means a * unit/pass-thru matrix should be used. This is generally the driver - * boot-up state too. + * boot-up state too. Drivers can access the blob for the color conversion + * matrix through &drm_crtc_state.ctm. * * “GAMMA_LUT”: * Blob property to set the gamma lookup table (LUT) mapping pixel data @@ -72,7 +74,8 @@ * * Setting this to NULL (blob property value set to 0) means a * linear/pass-thru gamma table should be used. This is generally the - * driver boot-up state too. + * driver boot-up state too. Drivers can access this blob through + * &drm_crtc_state.gamma_lut. * * “GAMMA_LUT_SIZE”: * Unsigned range property to give the size of the lookup table to be set --- a/include/drm/drm_crtc.h +++ b/include/drm/drm_crtc.h @@ -93,11 +93,6 @@ struct drm_plane_helper_funcs; * @adjusted_mode: for use by helpers and drivers to compute adjusted mode timings * @mode: current mode timings * @mode_blob: &drm_property_blob for @mode - * @degamma_lut: Lookup table for converting framebuffer pixel data - * before apply the conversion matrix - * @ctm: Transformation matrix - * @gamma_lut: Lookup table for converting pixel data after the - * conversion matrix * @state: backpointer to global drm_atomic_state * * Note that the distinction between @enable and @active is rather subtile: @@ -144,9 +139,30 @@ struct drm_crtc_state { /* blob property to expose current mode to atomic userspace */ struct drm_property_blob *mode_blob; - /* blob property to expose color management to userspace */ + /** + * @degamma_lut: + * + * Lookup table for converting framebuffer pixel data before apply the + * color conversion matrix @ctm. See drm_crtc_enable_color_mgmt(). The + * blob (if not NULL) is an array of &struct drm_color_lut. + */ struct drm_property_blob *degamma_lut; + + /** + * @ctm: + * + * Color transformation matrix. See drm_crtc_enable_color_mgmt(). The + * blob (if not NULL) is a &struct drm_color_ctm. + */ struct drm_property_blob *ctm; + + /** + * @gamma_lut: + * + * Lookup table for converting pixel data after the color conversion + * matrix @ctm. See drm_crtc_enable_color_mgmt(). The blob (if not + * NULL) is an array of &struct drm_color_lut. + */ struct drm_property_blob *gamma_lut; /** @@ -313,6 +329,12 @@ struct drm_crtc_funcs { * * This callback is optional. * + * Atomic drivers who want to support gamma tables should implement the + * atomic color management support, enabled by calling + * drm_crtc_enable_color_mgmt(), which then supports the legacy gamma + * interface through the drm_atomic_helper_legacy_gamma_set() + * compatibility implementation. + * * NOTE: * * Drivers that support gamma tables and also fbdev emulation through