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Kernel-level support for the Direct Rendering Infrastructure (DRI)
introduced in XFree86 4.0. If you say Y here, you need to select
diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c
index 923c4423151c..c649b4f9fd8e 100644
--- a/drivers/gpu/drm/drm_edid.c
+++ b/drivers/gpu/drm/drm_edid.c
@@ -28,6 +28,7 @@
* DEALINGS IN THE SOFTWARE.
*/
+#include <acpi/video.h>
#include <linux/bitfield.h>
#include <linux/cec.h>
#include <linux/hdmi.h>
@@ -2188,6 +2189,49 @@ drm_do_probe_ddc_edid(void *data, u8 *buf, unsigned int block, size_t len)
return ret == xfers ? 0 : -1;
}
+/**
+ * drm_do_probe_acpi_edid() - get EDID information via ACPI _DDC
+ * @data: struct drm_device
+ * @buf: EDID data buffer to be filled
+ * @block: 128 byte EDID block to start fetching from
+ * @len: EDID data buffer length to fetch
+ *
+ * Try to fetch EDID information by calling acpi_video_get_edid() function.
+ *
+ * Return: 0 on success or error code on failure.
+ */
+static int
+drm_do_probe_acpi_edid(void *data, u8 *buf, unsigned int block, size_t len)
+{
+ struct drm_device *ddev = data;
+ struct acpi_device *acpidev = ACPI_COMPANION(ddev->dev);
+ unsigned char start = block * EDID_LENGTH;
+ void *edid;
+ int r;
+
+ if (!acpidev)
+ return -ENODEV;
+
+ /* fetch the entire edid from BIOS */
+ r = acpi_video_get_edid(acpidev, ACPI_VIDEO_DISPLAY_LCD, -1, &edid);
+ if (r < 0) {
+ DRM_DEBUG_KMS("Failed to get EDID from ACPI: %d\n", r);
+ return -EINVAL;
+ }
+ if (len > r || start > r || start + len > r) {
+ r = -EINVAL;
+ goto cleanup;
+ }
+
+ memcpy(buf, edid + start, len);
+ r = 0;
+
+cleanup:
+ kfree(edid);
+
+ return r;
+}
+
static void connector_bad_edid(struct drm_connector *connector,
const struct edid *edid, int num_blocks)
{
@@ -2643,6 +2687,39 @@ struct edid *drm_get_edid(struct drm_connector *connector,
}
EXPORT_SYMBOL(drm_get_edid);
+/**
+ * drm_get_acpi_edid - get EDID data, if available
I'd prefer all the new EDID API to be named drm_edid_*. Makes a clean
break from the old API, and is more consistent.
So perhaps drm_edid_read_acpi() to be in line with all the other struct
drm_edid based EDID reading functions.
+ * @connector: connector we're probing
+ *
+ * Use the BIOS to attempt to grab EDID data if possible.
+ *
+ * The returned pointer must be freed using drm_edid_free().
+ *
+ * Return: Pointer to valid EDID or NULL if we couldn't find any.
+ */
+const struct drm_edid *drm_get_acpi_edid(struct drm_connector *connector)
+{
+ const struct drm_edid *drm_edid;
+
+ switch (connector->connector_type) {
+ case DRM_MODE_CONNECTOR_LVDS:
+ case DRM_MODE_CONNECTOR_eDP:
+ break;
+ default:
+ return NULL;
+ }
+
+ if (connector->force == DRM_FORCE_OFF)
+ return NULL;
+
+ drm_edid = drm_edid_read_custom(connector, drm_do_probe_acpi_edid, connector->dev);
+
+ /* Note: Do *not* call connector updates here. */
+
+ return drm_edid;
+}
+EXPORT_SYMBOL(drm_get_acpi_edid);
+
/**
* drm_edid_read_custom - Read EDID data using given EDID block read function
* @connector: Connector to use
diff --git a/include/drm/drm_edid.h b/include/drm/drm_edid.h
index 7923bc00dc7a..ca41be289fc6 100644
--- a/include/drm/drm_edid.h
+++ b/include/drm/drm_edid.h
@@ -410,6 +410,7 @@ 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);
+const struct drm_edid *drm_get_acpi_edid(struct drm_connector *connector);
There's a comment
/* Interface based on struct drm_edid */
towards the end of the file, gathering all the new API under it.
Other than that, LGTM,
BR,
Jani.
u32 drm_edid_get_panel_id(struct i2c_adapter *adapter);
struct edid *drm_get_edid_switcheroo(struct drm_connector *connector,
struct i2c_adapter *adapter);
--
Jani Nikula, Intel
