Message ID | 7fd382f989d169f6a03c473699e1385dd145069e.1648210803.git.jani.nikula@intel.com (mailing list archive) |
---|---|
State | New, archived |
Headers | show |
Series | drm/edid: constify EDID parsing | expand |
On Fri, Mar 25, 2022 at 02:25:25PM +0200, Jani Nikula wrote: > Use struct detailed_timing member access instead of direct offsets to > avoid casting. > > Use BUILD_BUG_ON() for sanity check. > > Cc: Ville Syrjälä <ville.syrjala@linux.intel.com> > Signed-off-by: Jani Nikula <jani.nikula@intel.com> > > --- > > Note: Why can we use range.formula.cvt.flags directly in is_rb() while > gtf2 functions check for range.flags == 0x02 first to ensure it's gtf2? Looks to me like is_rb() is just borked. Other weird stuff I just noticed is get_monitor_range() not doing anything for flags!=0x1 cases. It also fails to handle the other flags that were added to byte 4 in EDID 1.4. > --- > drivers/gpu/drm/drm_edid.c | 12 +++++++----- > 1 file changed, 7 insertions(+), 5 deletions(-) > > diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c > index 48707eef1dc2..5396fa78e864 100644 > --- a/drivers/gpu/drm/drm_edid.c > +++ b/drivers/gpu/drm/drm_edid.c > @@ -2405,15 +2405,17 @@ drm_for_each_detailed_block(u8 *raw_edid, detailed_cb *cb, void *closure) > } > > static void > -is_rb(struct detailed_timing *t, void *data) > +is_rb(struct detailed_timing *timing, void *data) > { > - u8 *r = (u8 *)t; > + bool *res = data; > > - if (!is_display_descriptor(t, EDID_DETAIL_MONITOR_RANGE)) > + if (!is_display_descriptor(timing, EDID_DETAIL_MONITOR_RANGE)) Calling this 'timing' when it's not is a bit confusing. I'd probably rename it to something else for all the display descriptor cases. > return; > > - if (r[15] & 0x10) > - *(bool *)data = true; > + BUILD_BUG_ON(offsetof(typeof(*timing), data.other_data.data.range.formula.cvt.flags) != 15); > + > + if (timing->data.other_data.data.range.formula.cvt.flags & 0x10) > + *res = true; > } > > /* EDID 1.4 defines this explicitly. For EDID 1.3, we guess, badly. */ > -- > 2.30.2
diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c index 48707eef1dc2..5396fa78e864 100644 --- a/drivers/gpu/drm/drm_edid.c +++ b/drivers/gpu/drm/drm_edid.c @@ -2405,15 +2405,17 @@ drm_for_each_detailed_block(u8 *raw_edid, detailed_cb *cb, void *closure) } static void -is_rb(struct detailed_timing *t, void *data) +is_rb(struct detailed_timing *timing, void *data) { - u8 *r = (u8 *)t; + bool *res = data; - if (!is_display_descriptor(t, EDID_DETAIL_MONITOR_RANGE)) + if (!is_display_descriptor(timing, EDID_DETAIL_MONITOR_RANGE)) return; - if (r[15] & 0x10) - *(bool *)data = true; + BUILD_BUG_ON(offsetof(typeof(*timing), data.other_data.data.range.formula.cvt.flags) != 15); + + if (timing->data.other_data.data.range.formula.cvt.flags & 0x10) + *res = true; } /* EDID 1.4 defines this explicitly. For EDID 1.3, we guess, badly. */
Use struct detailed_timing member access instead of direct offsets to avoid casting. Use BUILD_BUG_ON() for sanity check. Cc: Ville Syrjälä <ville.syrjala@linux.intel.com> Signed-off-by: Jani Nikula <jani.nikula@intel.com> --- Note: Why can we use range.formula.cvt.flags directly in is_rb() while gtf2 functions check for range.flags == 0x02 first to ensure it's gtf2? --- drivers/gpu/drm/drm_edid.c | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-)