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BAYES_HAM(-3.00)[100.00%]; NEURAL_HAM_LONG(-1.00)[-1.000]; MID_CONTAINS_FROM(1.00)[]; R_MISSING_CHARSET(0.50)[]; R_DKIM_ALLOW(-0.20)[suse.de:s=susede2_rsa,suse.de:s=susede2_ed25519]; NEURAL_HAM_SHORT(-0.20)[-1.000]; MIME_GOOD(-0.10)[text/plain]; MX_GOOD(-0.01)[]; RCPT_COUNT_TWELVE(0.00)[12]; TO_MATCH_ENVRCPT_ALL(0.00)[]; MIME_TRACE(0.00)[0:+]; DKIM_SIGNED(0.00)[suse.de:s=susede2_rsa,suse.de:s=susede2_ed25519]; ARC_NA(0.00)[]; FREEMAIL_TO(0.00)[redhat.com,kernel.org,linaro.org,linux.intel.com,ffwll.ch,gmail.com]; RCVD_TLS_ALL(0.00)[]; DKIM_TRACE(0.00)[suse.de:+]; SPAMHAUS_XBL(0.00)[2a07:de40:b281:104:10:150:64:97:from]; FROM_EQ_ENVFROM(0.00)[]; FROM_HAS_DN(0.00)[]; TO_DN_SOME(0.00)[]; RCVD_COUNT_TWO(0.00)[2]; DNSWL_BLOCKED(0.00)[2a07:de40:b281:104:10:150:64:97:from]; DBL_BLOCKED_OPENRESOLVER(0.00)[suse.de:dkim,suse.de:email,suse.de:mid,imap1.dmz-prg2.suse.org:helo,imap1.dmz-prg2.suse.org:rdns]; RCVD_VIA_SMTP_AUTH(0.00)[]; FREEMAIL_ENVRCPT(0.00)[gmail.com] X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" Add drm_edid_detect_panel_size() to extract the panel's preferred display resolution from a given EDID. Required for setting up DRM's panel orientation quirks in sysfb drivers. v4: - fix test for EDID PTD (Jani) v3: - mention use case in documentation (Jani) - use is_detailed_timing_descriptor() (Jani) - rename helper to drm_edid_detect_panel_size() v2: - handle EDID without pixel timing descriptor (Sashiko) - fix checks for width and height pointers Signed-off-by: Thomas Zimmermann Acked-by: Ard Biesheuvel --- drivers/gpu/drm/drm_edid.c | 47 ++++++++++++++++++++++++++++++++++++++ include/drm/drm_edid.h | 2 ++ 2 files changed, 49 insertions(+) diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c index 9990a836d0b6..1331efb4876c 100644 --- a/drivers/gpu/drm/drm_edid.c +++ b/drivers/gpu/drm/drm_edid.c @@ -7852,3 +7852,50 @@ bool drm_edid_is_digital(const struct drm_edid *drm_edid) drm_edid->edid->input & DRM_EDID_INPUT_DIGITAL; } EXPORT_SYMBOL(drm_edid_is_digital); + +/** + * drm_edid_detect_panel_size - Get a panel's size from EDID + * @drm_edid: EDID of the panel. + * @width: Returns the panel's width in pixels per scanline, if given + * @height: Returns the panel's height in scanlines, if given + * + * This function detects the preferred size of a panel from the given + * EDID. There is no such information stored in the EDID block directly, + * but the preferred mode often corresponds to the panel's native geometry. + * + * This helper should only be used during initialization before the + * connector is available. For regular use, retrieve the available display + * modes with the connector functions. + * + * Return: Zero on success, or a negative errno code otherwise. + */ +int drm_edid_detect_panel_size(const struct drm_edid *drm_edid, + unsigned int *width, unsigned int *height) +{ + const struct edid *edid = drm_edid->edid; + const struct detailed_timing *dt; + const struct detailed_pixel_timing *pt; + + /* + * Use display mode from the Preferred Timing Descriptor. For old + * and obscure displays, we might need better heuristics. + */ + + if (edid->revision < 4 || !(edid->features & DRM_EDID_FEATURE_PREFERRED_TIMING)) + return -EINVAL; /* no Preferred Timing Descriptor */ + + dt = &edid->detailed_timings[0]; + + if (!is_detailed_timing_descriptor(dt)) + return -EINVAL; + + pt = &dt->data.pixel_data; + + if (width) + *width = (pt->hactive_hblank_hi & 0xf0) << 4 | pt->hactive_lo; + if (height) + *height = (pt->vactive_vblank_hi & 0xf0) << 4 | pt->vactive_lo; + + return 0; +} +EXPORT_SYMBOL(drm_edid_detect_panel_size); diff --git a/include/drm/drm_edid.h b/include/drm/drm_edid.h index 04f7a7f1f108..a2617aa34edf 100644 --- a/include/drm/drm_edid.h +++ b/include/drm/drm_edid.h @@ -490,5 +490,7 @@ u32 drm_edid_get_panel_id(const struct drm_edid *drm_edid); bool drm_edid_match(const struct drm_edid *drm_edid, const struct drm_edid_ident *ident); bool drm_edid_has_quirk(struct drm_connector *connector, enum drm_edid_quirk quirk); +int drm_edid_detect_panel_size(const struct drm_edid *drm_edid, + unsigned int *width, unsigned int *height); #endif /* __DRM_EDID_H__ */ -- 2.55.0