Message ID | 9fe5f5c39039e585fecfffb390297d49262e5fd3.1648477901.git.jani.nikula@intel.com (mailing list archive) |
---|---|
State | New, archived |
Headers | show |
Series | drm/edid: constify EDID parsing, with fixes | expand |
On Mon, Mar 28, 2022 at 05:34:27PM +0300, 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> Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com> > --- > drivers/gpu/drm/drm_edid.c | 57 +++++++++++++++++++++++++------------- > 1 file changed, 37 insertions(+), 20 deletions(-) > > diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c > index 39c8bf4ca082..27a0e9bf260c 100644 > --- a/drivers/gpu/drm/drm_edid.c > +++ b/drivers/gpu/drm/drm_edid.c > @@ -2438,61 +2438,78 @@ drm_monitor_supports_rb(struct edid *edid) > } > > static void > -find_gtf2(struct detailed_timing *t, void *data) > +find_gtf2(struct detailed_timing *descriptor, void *data) > { > - u8 *r = (u8 *)t; > + struct detailed_timing **res = data; > > - if (!is_display_descriptor(t, EDID_DETAIL_MONITOR_RANGE)) > + if (!is_display_descriptor(descriptor, EDID_DETAIL_MONITOR_RANGE)) > return; > > - if (r[10] == 0x02) > - *(u8 **)data = r; > + BUILD_BUG_ON(offsetof(typeof(*descriptor), data.other_data.data.range.flags) != 10); > + > + if (descriptor->data.other_data.data.range.flags == 0x02) > + *res = descriptor; > } > > /* Secondary GTF curve kicks in above some break frequency */ > static int > drm_gtf2_hbreak(struct edid *edid) > { > - u8 *r = NULL; > + struct detailed_timing *descriptor = NULL; > + > + drm_for_each_detailed_block((u8 *)edid, find_gtf2, &descriptor); > > - drm_for_each_detailed_block((u8 *)edid, find_gtf2, &r); > - return r ? (r[12] * 2) : 0; > + BUILD_BUG_ON(offsetof(typeof(*descriptor), data.other_data.data.range.formula.gtf2.hfreq_start_khz) != 12); > + > + return descriptor ? descriptor->data.other_data.data.range.formula.gtf2.hfreq_start_khz * 2 : 0; > } > > static int > drm_gtf2_2c(struct edid *edid) > { > - u8 *r = NULL; > + struct detailed_timing *descriptor = NULL; > + > + drm_for_each_detailed_block((u8 *)edid, find_gtf2, &descriptor); > + > + BUILD_BUG_ON(offsetof(typeof(*descriptor), data.other_data.data.range.formula.gtf2.c) != 13); > > - drm_for_each_detailed_block((u8 *)edid, find_gtf2, &r); > - return r ? r[13] : 0; > + return descriptor ? descriptor->data.other_data.data.range.formula.gtf2.c : 0; > } > > static int > drm_gtf2_m(struct edid *edid) > { > - u8 *r = NULL; > + struct detailed_timing *descriptor = NULL; > > - drm_for_each_detailed_block((u8 *)edid, find_gtf2, &r); > - return r ? (r[15] << 8) + r[14] : 0; > + drm_for_each_detailed_block((u8 *)edid, find_gtf2, &descriptor); > + > + BUILD_BUG_ON(offsetof(typeof(*descriptor), data.other_data.data.range.formula.gtf2.m) != 14); > + > + return descriptor ? le16_to_cpu(descriptor->data.other_data.data.range.formula.gtf2.m) : 0; > } > > static int > drm_gtf2_k(struct edid *edid) > { > - u8 *r = NULL; > + struct detailed_timing *descriptor = NULL; > + > + drm_for_each_detailed_block((u8 *)edid, find_gtf2, &descriptor); > > - drm_for_each_detailed_block((u8 *)edid, find_gtf2, &r); > - return r ? r[16] : 0; > + BUILD_BUG_ON(offsetof(typeof(*descriptor), data.other_data.data.range.formula.gtf2.k) != 16); > + > + return descriptor ? descriptor->data.other_data.data.range.formula.gtf2.k : 0; > } > > static int > drm_gtf2_2j(struct edid *edid) > { > - u8 *r = NULL; > + struct detailed_timing *descriptor = NULL; > + > + drm_for_each_detailed_block((u8 *)edid, find_gtf2, &descriptor); > + > + BUILD_BUG_ON(offsetof(typeof(*descriptor), data.other_data.data.range.formula.gtf2.j) != 17); > > - drm_for_each_detailed_block((u8 *)edid, find_gtf2, &r); > - return r ? r[17] : 0; > + return descriptor ? descriptor->data.other_data.data.range.formula.gtf2.j : 0; > } > > /** > -- > 2.30.2
diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c index 39c8bf4ca082..27a0e9bf260c 100644 --- a/drivers/gpu/drm/drm_edid.c +++ b/drivers/gpu/drm/drm_edid.c @@ -2438,61 +2438,78 @@ drm_monitor_supports_rb(struct edid *edid) } static void -find_gtf2(struct detailed_timing *t, void *data) +find_gtf2(struct detailed_timing *descriptor, void *data) { - u8 *r = (u8 *)t; + struct detailed_timing **res = data; - if (!is_display_descriptor(t, EDID_DETAIL_MONITOR_RANGE)) + if (!is_display_descriptor(descriptor, EDID_DETAIL_MONITOR_RANGE)) return; - if (r[10] == 0x02) - *(u8 **)data = r; + BUILD_BUG_ON(offsetof(typeof(*descriptor), data.other_data.data.range.flags) != 10); + + if (descriptor->data.other_data.data.range.flags == 0x02) + *res = descriptor; } /* Secondary GTF curve kicks in above some break frequency */ static int drm_gtf2_hbreak(struct edid *edid) { - u8 *r = NULL; + struct detailed_timing *descriptor = NULL; + + drm_for_each_detailed_block((u8 *)edid, find_gtf2, &descriptor); - drm_for_each_detailed_block((u8 *)edid, find_gtf2, &r); - return r ? (r[12] * 2) : 0; + BUILD_BUG_ON(offsetof(typeof(*descriptor), data.other_data.data.range.formula.gtf2.hfreq_start_khz) != 12); + + return descriptor ? descriptor->data.other_data.data.range.formula.gtf2.hfreq_start_khz * 2 : 0; } static int drm_gtf2_2c(struct edid *edid) { - u8 *r = NULL; + struct detailed_timing *descriptor = NULL; + + drm_for_each_detailed_block((u8 *)edid, find_gtf2, &descriptor); + + BUILD_BUG_ON(offsetof(typeof(*descriptor), data.other_data.data.range.formula.gtf2.c) != 13); - drm_for_each_detailed_block((u8 *)edid, find_gtf2, &r); - return r ? r[13] : 0; + return descriptor ? descriptor->data.other_data.data.range.formula.gtf2.c : 0; } static int drm_gtf2_m(struct edid *edid) { - u8 *r = NULL; + struct detailed_timing *descriptor = NULL; - drm_for_each_detailed_block((u8 *)edid, find_gtf2, &r); - return r ? (r[15] << 8) + r[14] : 0; + drm_for_each_detailed_block((u8 *)edid, find_gtf2, &descriptor); + + BUILD_BUG_ON(offsetof(typeof(*descriptor), data.other_data.data.range.formula.gtf2.m) != 14); + + return descriptor ? le16_to_cpu(descriptor->data.other_data.data.range.formula.gtf2.m) : 0; } static int drm_gtf2_k(struct edid *edid) { - u8 *r = NULL; + struct detailed_timing *descriptor = NULL; + + drm_for_each_detailed_block((u8 *)edid, find_gtf2, &descriptor); - drm_for_each_detailed_block((u8 *)edid, find_gtf2, &r); - return r ? r[16] : 0; + BUILD_BUG_ON(offsetof(typeof(*descriptor), data.other_data.data.range.formula.gtf2.k) != 16); + + return descriptor ? descriptor->data.other_data.data.range.formula.gtf2.k : 0; } static int drm_gtf2_2j(struct edid *edid) { - u8 *r = NULL; + struct detailed_timing *descriptor = NULL; + + drm_for_each_detailed_block((u8 *)edid, find_gtf2, &descriptor); + + BUILD_BUG_ON(offsetof(typeof(*descriptor), data.other_data.data.range.formula.gtf2.j) != 17); - drm_for_each_detailed_block((u8 *)edid, find_gtf2, &r); - return r ? r[17] : 0; + return descriptor ? descriptor->data.other_data.data.range.formula.gtf2.j : 0; } /**
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> --- drivers/gpu/drm/drm_edid.c | 57 +++++++++++++++++++++++++------------- 1 file changed, 37 insertions(+), 20 deletions(-)