| Message ID | 20240818-amdgpu-drm_edid-v1-10-aea66c1f7cf4@weissschuh.net (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | drm/amd: Switch over to struct drm_edid | expand |
On Sun, 18 Aug 2024, Thomas Weißschuh <linux@weissschuh.net> wrote: > As struct drm_edid is opaque, drivers can't directly memcmp() the > contained data. Add a helper to provide this functionality. I'm not sure why drivers would need to compare EDIDs. The only user was added in commit eb815442e840 ("drm/amd/display: don't create new dc_sink if nothing changed at detection") with absolutely no explanation why. Other drivers use connector->epoch_counter to see if the EDID or status changed. BR, Jani. > > Signed-off-by: Thomas Weißschuh <linux@weissschuh.net> > --- > drivers/gpu/drm/drm_edid.c | 18 ++++++++++++++++++ > include/drm/drm_edid.h | 1 + > 2 files changed, 19 insertions(+) > > diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c > index 69fb11741abd..c2493c983a64 100644 > --- a/drivers/gpu/drm/drm_edid.c > +++ b/drivers/gpu/drm/drm_edid.c > @@ -1840,6 +1840,24 @@ static bool drm_edid_eq(const struct drm_edid *drm_edid, > return true; > } > > +/** > + * drm_edid_equal - compare two EDID > + * @drm_edid_a: First EDID data > + * @drm_edid_b: Second EDID data > + * > + * Compare two EDIDs for equality (including extensions) > + * > + * Return: True if the EDIDs are equal, false otherwise. > + */ > +bool drm_edid_equal(const struct drm_edid *drm_edid_a, const struct drm_edid *drm_edid_b) > +{ > + if (!drm_edid_b) > + return !drm_edid_a; > + > + return drm_edid_eq(drm_edid_a, drm_edid_b->edid, drm_edid_b->size); > +} > +EXPORT_SYMBOL(drm_edid_equal); > + > enum edid_block_status { > EDID_BLOCK_OK = 0, > EDID_BLOCK_READ_FAIL, > diff --git a/include/drm/drm_edid.h b/include/drm/drm_edid.h > index a5b377c4a342..35b40a9d3350 100644 > --- a/include/drm/drm_edid.h > +++ b/include/drm/drm_edid.h > @@ -456,6 +456,7 @@ drm_display_mode_from_cea_vic(struct drm_device *dev, > const struct drm_edid *drm_edid_alloc(const void *edid, size_t size); > const struct drm_edid *drm_edid_dup(const struct drm_edid *drm_edid); > void drm_edid_free(const struct drm_edid *drm_edid); > +bool drm_edid_equal(const struct drm_edid *drm_edid_a, const struct drm_edid *drm_edid_b); > bool drm_edid_valid(const struct drm_edid *drm_edid); > const struct edid *drm_edid_raw(const struct drm_edid *drm_edid); > const struct drm_edid *drm_edid_read(struct drm_connector *connector);
diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c index 69fb11741abd..c2493c983a64 100644 --- a/drivers/gpu/drm/drm_edid.c +++ b/drivers/gpu/drm/drm_edid.c @@ -1840,6 +1840,24 @@ static bool drm_edid_eq(const struct drm_edid *drm_edid, return true; } +/** + * drm_edid_equal - compare two EDID + * @drm_edid_a: First EDID data + * @drm_edid_b: Second EDID data + * + * Compare two EDIDs for equality (including extensions) + * + * Return: True if the EDIDs are equal, false otherwise. + */ +bool drm_edid_equal(const struct drm_edid *drm_edid_a, const struct drm_edid *drm_edid_b) +{ + if (!drm_edid_b) + return !drm_edid_a; + + return drm_edid_eq(drm_edid_a, drm_edid_b->edid, drm_edid_b->size); +} +EXPORT_SYMBOL(drm_edid_equal); + enum edid_block_status { EDID_BLOCK_OK = 0, EDID_BLOCK_READ_FAIL, diff --git a/include/drm/drm_edid.h b/include/drm/drm_edid.h index a5b377c4a342..35b40a9d3350 100644 --- a/include/drm/drm_edid.h +++ b/include/drm/drm_edid.h @@ -456,6 +456,7 @@ drm_display_mode_from_cea_vic(struct drm_device *dev, const struct drm_edid *drm_edid_alloc(const void *edid, size_t size); const struct drm_edid *drm_edid_dup(const struct drm_edid *drm_edid); void drm_edid_free(const struct drm_edid *drm_edid); +bool drm_edid_equal(const struct drm_edid *drm_edid_a, const struct drm_edid *drm_edid_b); bool drm_edid_valid(const struct drm_edid *drm_edid); const struct edid *drm_edid_raw(const struct drm_edid *drm_edid); const struct drm_edid *drm_edid_read(struct drm_connector *connector);
As struct drm_edid is opaque, drivers can't directly memcmp() the contained data. Add a helper to provide this functionality. Signed-off-by: Thomas Weißschuh <linux@weissschuh.net> --- drivers/gpu/drm/drm_edid.c | 18 ++++++++++++++++++ include/drm/drm_edid.h | 1 + 2 files changed, 19 insertions(+)