diff options
| -rw-r--r-- | drivers/gpu/drm/drm_edid.c | 71 | ||||
| -rw-r--r-- | drivers/gpu/drm/panel/panel-edp.c | 8 | ||||
| -rw-r--r-- | include/drm/drm_edid.h | 3 |
3 files changed, 50 insertions, 32 deletions
diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c index 923c4423151c..ecd6e9255b67 100644 --- a/drivers/gpu/drm/drm_edid.c +++ b/drivers/gpu/drm/drm_edid.c @@ -2749,8 +2749,27 @@ const struct drm_edid *drm_edid_read(struct drm_connector *connector) } EXPORT_SYMBOL(drm_edid_read); -static u32 edid_extract_panel_id(const struct edid *edid) +/** + * drm_edid_get_panel_id - Get a panel's ID from EDID + * @drm_edid: EDID that contains panel ID. + * + * This function uses the first block of the EDID of a panel and (assuming + * that the EDID is valid) extracts the ID out of it. The ID is a 32-bit value + * (16 bits of manufacturer ID and 16 bits of per-manufacturer ID) that's + * supposed to be different for each different modem of panel. + * + * Return: A 32-bit ID that should be different for each make/model of panel. + * See the functions drm_edid_encode_panel_id() and + * drm_edid_decode_panel_id() for some details on the structure of this + * ID. Return 0 if the EDID size is less than a base block. + */ +u32 drm_edid_get_panel_id(const struct drm_edid *drm_edid) { + const struct edid *edid = drm_edid->edid; + + if (drm_edid->size < EDID_LENGTH) + return 0; + /* * We represent the ID as a 32-bit number so it can easily be compared * with "==". @@ -2768,60 +2787,54 @@ static u32 edid_extract_panel_id(const struct edid *edid) (u32)edid->mfg_id[1] << 16 | (u32)EDID_PRODUCT_ID(edid); } +EXPORT_SYMBOL(drm_edid_get_panel_id); /** - * drm_edid_get_panel_id - Get a panel's ID through DDC + * drm_edid_read_base_block - Get a panel's EDID base block * @adapter: I2C adapter to use for DDC * - * This function reads the first block of the EDID of a panel and (assuming - * that the EDID is valid) extracts the ID out of it. The ID is a 32-bit value - * (16 bits of manufacturer ID and 16 bits of per-manufacturer ID) that's - * supposed to be different for each different modem of panel. + * This function returns the drm_edid containing the first block of the EDID of + * a panel. * * This function is intended to be used during early probing on devices where * more than one panel might be present. Because of its intended use it must - * assume that the EDID of the panel is correct, at least as far as the ID - * is concerned (in other words, we don't process any overrides here). + * assume that the EDID of the panel is correct, at least as far as the base + * block is concerned (in other words, we don't process any overrides here). + * + * Caller should call drm_edid_free() after use. * * NOTE: it's expected that this function and drm_do_get_edid() will both * be read the EDID, but there is no caching between them. Since we're only * reading the first block, hopefully this extra overhead won't be too big. * - * Return: A 32-bit ID that should be different for each make/model of panel. - * See the functions drm_edid_encode_panel_id() and - * drm_edid_decode_panel_id() for some details on the structure of this - * ID. + * WARNING: Only use this function when the connector is unknown. For example, + * during the early probe of panel. The EDID read from the function is temporary + * and should be replaced by the full EDID returned from other drm_edid_read. + * + * Return: Pointer to allocated EDID base block, or NULL on any failure. */ - -u32 drm_edid_get_panel_id(struct i2c_adapter *adapter) +const struct drm_edid *drm_edid_read_base_block(struct i2c_adapter *adapter) { enum edid_block_status status; void *base_block; - u32 panel_id = 0; - - /* - * There are no manufacturer IDs of 0, so if there is a problem reading - * the EDID then we'll just return 0. - */ base_block = kzalloc(EDID_LENGTH, GFP_KERNEL); if (!base_block) - return 0; + return NULL; status = edid_block_read(base_block, 0, drm_do_probe_ddc_edid, adapter); edid_block_status_print(status, base_block, 0); - if (edid_block_status_valid(status, edid_block_tag(base_block))) - panel_id = edid_extract_panel_id(base_block); - else + if (!edid_block_status_valid(status, edid_block_tag(base_block))) { edid_block_dump(KERN_NOTICE, base_block, 0); + kfree(base_block); + return NULL; + } - kfree(base_block); - - return panel_id; + return _drm_edid_alloc(base_block, EDID_LENGTH); } -EXPORT_SYMBOL(drm_edid_get_panel_id); +EXPORT_SYMBOL(drm_edid_read_base_block); /** * drm_get_edid_switcheroo - get EDID data for a vga_switcheroo output @@ -2906,7 +2919,7 @@ EXPORT_SYMBOL(drm_edid_duplicate); */ static u32 edid_get_quirks(const struct drm_edid *drm_edid) { - u32 panel_id = edid_extract_panel_id(drm_edid->edid); + u32 panel_id = drm_edid_get_panel_id(drm_edid); const struct edid_quirk *quirk; int i; diff --git a/drivers/gpu/drm/panel/panel-edp.c b/drivers/gpu/drm/panel/panel-edp.c index 2906a382aae0..f7db5b10e233 100644 --- a/drivers/gpu/drm/panel/panel-edp.c +++ b/drivers/gpu/drm/panel/panel-edp.c @@ -766,6 +766,7 @@ static const struct edp_panel_entry *find_edp_panel(u32 panel_id); static int generic_edp_panel_probe(struct device *dev, struct panel_edp *panel) { struct panel_desc *desc; + const struct drm_edid *base_block; u32 panel_id; char vend[4]; u16 product_id; @@ -795,8 +796,11 @@ static int generic_edp_panel_probe(struct device *dev, struct panel_edp *panel) goto exit; } - panel_id = drm_edid_get_panel_id(panel->ddc); - if (!panel_id) { + base_block = drm_edid_read_base_block(panel->ddc); + if (base_block) { + panel_id = drm_edid_get_panel_id(base_block); + drm_edid_free(base_block); + } else { dev_err(dev, "Couldn't identify panel via EDID\n"); ret = -EIO; goto exit; diff --git a/include/drm/drm_edid.h b/include/drm/drm_edid.h index 7923bc00dc7a..9686a7cee6a6 100644 --- a/include/drm/drm_edid.h +++ b/include/drm/drm_edid.h @@ -410,7 +410,8 @@ struct edid *drm_do_get_edid(struct drm_connector *connector, void *data); struct edid *drm_get_edid(struct drm_connector *connector, struct i2c_adapter *adapter); -u32 drm_edid_get_panel_id(struct i2c_adapter *adapter); +const struct drm_edid *drm_edid_read_base_block(struct i2c_adapter *adapter); +u32 drm_edid_get_panel_id(const struct drm_edid *drm_edid); struct edid *drm_get_edid_switcheroo(struct drm_connector *connector, struct i2c_adapter *adapter); struct edid *drm_edid_duplicate(const struct edid *edid); |