| Message ID | 1485884628-4838-1-git-send-email-brian.starkey@arm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Tue, Jan 31, 2017 at 05:43:48PM +0000, Brian Starkey wrote: > Explicitly state the expected CTM equations in the kerneldoc for the CTM > property, and the form of the matrix on struct drm_color_ctm. > > Cc: Ville Syrjälä <ville.syrjala@linux.intel.com> > Cc: Lionel Landwerlin <lionel.g.landwerlin@intel.com> > Cc: Daniel Vetter <daniel.vetter@ffwll.ch> > Signed-off-by: Brian Starkey <brian.starkey@arm.com> Ugh, but well that's the current uabi. Applied to drm-misc-next, thanks for your patch. One idea below. > --- > drivers/gpu/drm/drm_color_mgmt.c | 13 +++++++++++++ > include/uapi/drm/drm_mode.h | 14 +++++++++++++- > 2 files changed, 26 insertions(+), 1 deletion(-) > > diff --git a/drivers/gpu/drm/drm_color_mgmt.c b/drivers/gpu/drm/drm_color_mgmt.c > index 789b4c65cd69..307f7b0545b6 100644 > --- a/drivers/gpu/drm/drm_color_mgmt.c > +++ b/drivers/gpu/drm/drm_color_mgmt.c > @@ -62,6 +62,19 @@ > * unit/pass-thru matrix should be used. This is generally the driver > * boot-up state too. > * > + * The output vector is related to the input vector as below:: > + * > + * out[0] = matrix[0] * in[0] + matrix[1] * in[1] + matrix[2] * in[2]; > + * out[1] = matrix[3] * in[0] + matrix[4] * in[1] + matrix[5] * in[2]; > + * out[2] = matrix[6] * in[0] + matrix[7] * in[1] + matrix[8] * in[2]; > + * > + * The component order in the input/output vectors is assumed to be > + * { R, G, B }. > + * > + * The color-space of the input vector must not be confused with the > + * color-space implied by a framebuffer pixel format, which may be the same > + * or different. > + * > * “GAMMA_LUT”: > * Blob property to set the gamma lookup table (LUT) mapping pixel data > * after the transformation matrix to data sent to the connector. The > diff --git a/include/uapi/drm/drm_mode.h b/include/uapi/drm/drm_mode.h > index ce7efe2e8a5e..3f179b8867e5 100644 > --- a/include/uapi/drm/drm_mode.h > +++ b/include/uapi/drm/drm_mode.h > @@ -525,7 +525,19 @@ struct drm_mode_crtc_lut { > }; > > struct drm_color_ctm { > - /* Conversion matrix in S31.32 format. */ > + /* > + * Conversion matrix in row-major form: > + * > + * | matrix[0] matrix[1] matrix[2] | > + * | matrix[3] matrix[4] matrix[5] | > + * | matrix[6] matrix[7] matrix[8] | > + * > + * Each element is in a sign + magnitude format: S31.32, with the sign > + * in bit 63, and the magnitude represented as fixed-point 31.32. > + * > + * i.e. +1.25 = 0x00000001.40000000 > + * -1.25 = 0x80000001.40000000 > + */ This is great, except none of our uabi headers are part of the kernel-doc build :( If you have time, would be real awesome to include them, and at least give this struct here a proper kernel-doc. Then you could also reference it in the above kerneldoc comment in drm_color_mgmt.c. We already have a drm-uapi.rst file, adding a new section there for userspace abi headers seems like the right place for the include stanza. Cheers, Daniel > __s64 matrix[9]; > }; > > -- > 1.7.9.5 >
diff --git a/drivers/gpu/drm/drm_color_mgmt.c b/drivers/gpu/drm/drm_color_mgmt.c index 789b4c65cd69..307f7b0545b6 100644 --- a/drivers/gpu/drm/drm_color_mgmt.c +++ b/drivers/gpu/drm/drm_color_mgmt.c @@ -62,6 +62,19 @@ * unit/pass-thru matrix should be used. This is generally the driver * boot-up state too. * + * The output vector is related to the input vector as below:: + * + * out[0] = matrix[0] * in[0] + matrix[1] * in[1] + matrix[2] * in[2]; + * out[1] = matrix[3] * in[0] + matrix[4] * in[1] + matrix[5] * in[2]; + * out[2] = matrix[6] * in[0] + matrix[7] * in[1] + matrix[8] * in[2]; + * + * The component order in the input/output vectors is assumed to be + * { R, G, B }. + * + * The color-space of the input vector must not be confused with the + * color-space implied by a framebuffer pixel format, which may be the same + * or different. + * * “GAMMA_LUT”: * Blob property to set the gamma lookup table (LUT) mapping pixel data * after the transformation matrix to data sent to the connector. The diff --git a/include/uapi/drm/drm_mode.h b/include/uapi/drm/drm_mode.h index ce7efe2e8a5e..3f179b8867e5 100644 --- a/include/uapi/drm/drm_mode.h +++ b/include/uapi/drm/drm_mode.h @@ -525,7 +525,19 @@ struct drm_mode_crtc_lut { }; struct drm_color_ctm { - /* Conversion matrix in S31.32 format. */ + /* + * Conversion matrix in row-major form: + * + * | matrix[0] matrix[1] matrix[2] | + * | matrix[3] matrix[4] matrix[5] | + * | matrix[6] matrix[7] matrix[8] | + * + * Each element is in a sign + magnitude format: S31.32, with the sign + * in bit 63, and the magnitude represented as fixed-point 31.32. + * + * i.e. +1.25 = 0x00000001.40000000 + * -1.25 = 0x80000001.40000000 + */ __s64 matrix[9]; };
Explicitly state the expected CTM equations in the kerneldoc for the CTM property, and the form of the matrix on struct drm_color_ctm. Cc: Ville Syrjälä <ville.syrjala@linux.intel.com> Cc: Lionel Landwerlin <lionel.g.landwerlin@intel.com> Cc: Daniel Vetter <daniel.vetter@ffwll.ch> Signed-off-by: Brian Starkey <brian.starkey@arm.com> --- drivers/gpu/drm/drm_color_mgmt.c | 13 +++++++++++++ include/uapi/drm/drm_mode.h | 14 +++++++++++++- 2 files changed, 26 insertions(+), 1 deletion(-)