diff options
| -rw-r--r-- | drivers/gpu/drm/drm_edid.c | 245 | ||||
| -rw-r--r-- | include/drm/drm_edid.h | 9 |
2 files changed, 230 insertions, 24 deletions
diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c index 2beaa48301c1..2bdaf1e34a9d 100644 --- a/drivers/gpu/drm/drm_edid.c +++ b/drivers/gpu/drm/drm_edid.c @@ -2226,29 +2226,9 @@ static enum edid_block_status edid_block_read(void *block, unsigned int block_nu return status; } -/** - * drm_do_get_edid - get EDID data using a custom EDID block read function - * @connector: connector we're probing - * @read_block: EDID block read function - * @context: private data passed to the block read function - * - * When the I2C adapter connected to the DDC bus is hidden behind a device that - * exposes a different interface to read EDID blocks this function can be used - * to get EDID data using a custom block read function. - * - * As in the general case the DDC bus is accessible by the kernel at the I2C - * level, drivers must make all reasonable efforts to expose it as an I2C - * adapter and use drm_get_edid() instead of abusing this function. - * - * The EDID may be overridden using debugfs override_edid or firmware EDID - * (drm_load_edid_firmware() and drm.edid_firmware parameter), in this priority - * order. Having either of them bypasses actual EDID reads. - * - * Return: Pointer to valid EDID or NULL if we couldn't find any. - */ -struct edid *drm_do_get_edid(struct drm_connector *connector, - read_block_fn read_block, - void *context) +static struct edid *_drm_do_get_edid(struct drm_connector *connector, + read_block_fn read_block, void *context, + size_t *size) { enum edid_block_status status; int i, invalid_blocks = 0; @@ -2315,14 +2295,125 @@ struct edid *drm_do_get_edid(struct drm_connector *connector, } ok: + if (size) + *size = alloc_size; + return edid; fail: kfree(edid); return NULL; } + +/** + * drm_do_get_edid - get EDID data using a custom EDID block read function + * @connector: connector we're probing + * @read_block: EDID block read function + * @context: private data passed to the block read function + * + * When the I2C adapter connected to the DDC bus is hidden behind a device that + * exposes a different interface to read EDID blocks this function can be used + * to get EDID data using a custom block read function. + * + * As in the general case the DDC bus is accessible by the kernel at the I2C + * level, drivers must make all reasonable efforts to expose it as an I2C + * adapter and use drm_get_edid() instead of abusing this function. + * + * The EDID may be overridden using debugfs override_edid or firmware EDID + * (drm_load_edid_firmware() and drm.edid_firmware parameter), in this priority + * order. Having either of them bypasses actual EDID reads. + * + * Return: Pointer to valid EDID or NULL if we couldn't find any. + */ +struct edid *drm_do_get_edid(struct drm_connector *connector, + read_block_fn read_block, + void *context) +{ + return _drm_do_get_edid(connector, read_block, context, NULL); +} EXPORT_SYMBOL_GPL(drm_do_get_edid); +/* Allocate struct drm_edid container *without* duplicating the edid data */ +static const struct drm_edid *_drm_edid_alloc(const void *edid, size_t size) +{ + struct drm_edid *drm_edid; + + if (!edid || !size || size < EDID_LENGTH) + return NULL; + + drm_edid = kzalloc(sizeof(*drm_edid), GFP_KERNEL); + if (drm_edid) { + drm_edid->edid = edid; + drm_edid->size = size; + } + + return drm_edid; +} + +/** + * drm_edid_alloc - Allocate a new drm_edid container + * @edid: Pointer to raw EDID data + * @size: Size of memory allocated for EDID + * + * Allocate a new drm_edid container. Do not calculate edid size from edid, pass + * the actual size that has been allocated for the data. There is no validation + * of the raw EDID data against the size, but at least the EDID base block must + * fit in the buffer. + * + * The returned pointer must be freed using drm_edid_free(). + * + * Return: drm_edid container, or NULL on errors + */ +const struct drm_edid *drm_edid_alloc(const void *edid, size_t size) +{ + const struct drm_edid *drm_edid; + + if (!edid || !size || size < EDID_LENGTH) + return NULL; + + edid = kmemdup(edid, size, GFP_KERNEL); + if (!edid) + return NULL; + + drm_edid = _drm_edid_alloc(edid, size); + if (!drm_edid) + kfree(edid); + + return drm_edid; +} +EXPORT_SYMBOL(drm_edid_alloc); + +/** + * drm_edid_dup - Duplicate a drm_edid container + * @drm_edid: EDID to duplicate + * + * The returned pointer must be freed using drm_edid_free(). + * + * Returns: drm_edid container copy, or NULL on errors + */ +const struct drm_edid *drm_edid_dup(const struct drm_edid *drm_edid) +{ + if (!drm_edid) + return NULL; + + return drm_edid_alloc(drm_edid->edid, drm_edid->size); +} +EXPORT_SYMBOL(drm_edid_dup); + +/** + * drm_edid_free - Free the drm_edid container + * @drm_edid: EDID to free + */ +void drm_edid_free(const struct drm_edid *drm_edid) +{ + if (!drm_edid) + return; + + kfree(drm_edid->edid); + kfree(drm_edid); +} +EXPORT_SYMBOL(drm_edid_free); + /** * drm_probe_ddc() - probe DDC presence * @adapter: I2C adapter to probe @@ -2359,12 +2450,118 @@ struct edid *drm_get_edid(struct drm_connector *connector, if (connector->force == DRM_FORCE_UNSPECIFIED && !drm_probe_ddc(adapter)) return NULL; - edid = drm_do_get_edid(connector, drm_do_probe_ddc_edid, adapter); + edid = _drm_do_get_edid(connector, drm_do_probe_ddc_edid, adapter, NULL); drm_connector_update_edid_property(connector, edid); return edid; } EXPORT_SYMBOL(drm_get_edid); +/** + * drm_edid_read_custom - Read EDID data using given EDID block read function + * @connector: Connector to use + * @read_block: EDID block read function + * @context: Private data passed to the block read function + * + * When the I2C adapter connected to the DDC bus is hidden behind a device that + * exposes a different interface to read EDID blocks this function can be used + * to get EDID data using a custom block read function. + * + * As in the general case the DDC bus is accessible by the kernel at the I2C + * level, drivers must make all reasonable efforts to expose it as an I2C + * adapter and use drm_edid_read() or drm_edid_read_ddc() instead of abusing + * this function. + * + * The EDID may be overridden using debugfs override_edid or firmware EDID + * (drm_load_edid_firmware() and drm.edid_firmware parameter), in this priority + * order. Having either of them bypasses actual EDID reads. + * + * The returned pointer must be freed using drm_edid_free(). + * + * Return: Pointer to EDID, or NULL if probe/read failed. + */ +const struct drm_edid *drm_edid_read_custom(struct drm_connector *connector, + read_block_fn read_block, + void *context) +{ + const struct drm_edid *drm_edid; + struct edid *edid; + size_t size = 0; + + edid = _drm_do_get_edid(connector, read_block, context, &size); + if (!edid) + return NULL; + + /* Sanity check for now */ + drm_WARN_ON(connector->dev, !size); + + drm_edid = _drm_edid_alloc(edid, size); + if (!drm_edid) + kfree(edid); + + return drm_edid; +} +EXPORT_SYMBOL(drm_edid_read_custom); + +/** + * drm_edid_read_ddc - Read EDID data using given I2C adapter + * @connector: Connector to use + * @adapter: I2C adapter to use for DDC + * + * Read EDID using the given I2C adapter. + * + * The EDID may be overridden using debugfs override_edid or firmware EDID + * (drm_load_edid_firmware() and drm.edid_firmware parameter), in this priority + * order. Having either of them bypasses actual EDID reads. + * + * Prefer initializing connector->ddc with drm_connector_init_with_ddc() and + * using drm_edid_read() instead of this function. + * + * The returned pointer must be freed using drm_edid_free(). + * + * Return: Pointer to EDID, or NULL if probe/read failed. + */ +const struct drm_edid *drm_edid_read_ddc(struct drm_connector *connector, + struct i2c_adapter *adapter) +{ + const struct drm_edid *drm_edid; + + if (connector->force == DRM_FORCE_OFF) + return NULL; + + if (connector->force == DRM_FORCE_UNSPECIFIED && !drm_probe_ddc(adapter)) + return NULL; + + drm_edid = drm_edid_read_custom(connector, drm_do_probe_ddc_edid, adapter); + + /* Note: Do *not* call connector updates here. */ + + return drm_edid; +} +EXPORT_SYMBOL(drm_edid_read_ddc); + +/** + * drm_edid_read - Read EDID data using connector's I2C adapter + * @connector: Connector to use + * + * Read EDID using the connector's I2C adapter. + * + * The EDID may be overridden using debugfs override_edid or firmware EDID + * (drm_load_edid_firmware() and drm.edid_firmware parameter), in this priority + * order. Having either of them bypasses actual EDID reads. + * + * The returned pointer must be freed using drm_edid_free(). + * + * Return: Pointer to EDID, or NULL if probe/read failed. + */ +const struct drm_edid *drm_edid_read(struct drm_connector *connector) +{ + if (drm_WARN_ON(connector->dev, !connector->ddc)) + return NULL; + + return drm_edid_read_ddc(connector, connector->ddc); +} +EXPORT_SYMBOL(drm_edid_read); + static u32 edid_extract_panel_id(const struct edid *edid) { /* diff --git a/include/drm/drm_edid.h b/include/drm/drm_edid.h index 1d5950b5b407..c592d2c1afed 100644 --- a/include/drm/drm_edid.h +++ b/include/drm/drm_edid.h @@ -594,6 +594,15 @@ drm_display_mode_from_cea_vic(struct drm_device *dev, u8 video_code); /* Interface based on struct drm_edid */ +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); +const struct drm_edid *drm_edid_read(struct drm_connector *connector); +const struct drm_edid *drm_edid_read_ddc(struct drm_connector *connector, + struct i2c_adapter *adapter); +const struct drm_edid *drm_edid_read_custom(struct drm_connector *connector, + int (*read_block)(void *context, u8 *buf, unsigned int block, size_t len), + void *context); const u8 *drm_find_edid_extension(const struct drm_edid *drm_edid, int ext_id, int *ext_index); |