drm/radeon: convert bios_hardcoded_edid to drm_edid

Instead of manually passing around 'struct edid *' and its size,
use 'struct drm_edid', which encapsulates a validated combination of
both.

As the drm_edid_ can handle NULL gracefully, the explicit checks can be
dropped.

Also save a few characters by transforming '&array[0]' to the equivalent
'array' and using 'max_t(int, ...)' instead of manual casts.

Signed-off-by: Thomas Weißschuh <[e-mail]>
Signed-off-by: Alex Deucher <[e-mail]>

drivers/gpu/drm/radeon/radeon_atombios.c

···
 				case LCD_FAKE_EDID_PATCH_RECORD_TYPE:
 					fake_edid_record = (ATOM_FAKE_EDID_PATCH_RECORD *)record;
 					if (fake_edid_record->ucFakeEDIDLength) {
-						struct edid *edid;
+						const struct drm_edid *edid;
 						int edid_size;
 
 						if (fake_edid_record->ucFakeEDIDLength == 128)
 							edid_size = fake_edid_record->ucFakeEDIDLength;
 						else
 							edid_size = fake_edid_record->ucFakeEDIDLength * 128;
-						edid = kmemdup(&fake_edid_record->ucFakeEDIDString[0],
-							       edid_size, GFP_KERNEL);
-						if (edid) {
-							if (drm_edid_is_valid(edid)) {
-								rdev->mode_info.bios_hardcoded_edid = edid;
-								rdev->mode_info.bios_hardcoded_edid_size = edid_size;
-							} else {
-								kfree(edid);
-							}
-						}
+						edid = drm_edid_alloc(fake_edid_record->ucFakeEDIDString, edid_size);
+						if (drm_edid_valid(edid))
+							rdev->mode_info.bios_hardcoded_edid = edid;
+						else
+							drm_edid_free(edid);
 						record += struct_size(fake_edid_record,
 								      ucFakeEDIDString,
 								      edid_size);

drivers/gpu/drm/radeon/radeon_combios.c

···
 bool radeon_combios_check_hardcoded_edid(struct radeon_device *rdev)
 {
 	int edid_info, size;
-	struct edid *edid;
+	const struct drm_edid *edid;
 	unsigned char *raw;
 	edid_info = combios_get_table_offset(rdev_to_drm(rdev), COMBIOS_HARDCODED_EDID_TABLE);
 	if (!edid_info)
···
 
 	raw = rdev->bios + edid_info;
 	size = EDID_LENGTH * (raw[0x7e] + 1);
-	edid = kmalloc(size, GFP_KERNEL);
-	if (edid == NULL)
-		return false;
+	edid = drm_edid_alloc(raw, size);
 
-	memcpy((unsigned char *)edid, raw, size);
-
-	if (!drm_edid_is_valid(edid)) {
-		kfree(edid);
+	if (!drm_edid_valid(edid)) {
+		drm_edid_free(edid);
 		return false;
 	}
 
 	rdev->mode_info.bios_hardcoded_edid = edid;
-	rdev->mode_info.bios_hardcoded_edid_size = size;
 	return true;
 }
 
···
 struct edid *
 radeon_bios_get_hardcoded_edid(struct radeon_device *rdev)
 {
-	struct edid *edid;
-
-	if (rdev->mode_info.bios_hardcoded_edid) {
-		edid = kmalloc(rdev->mode_info.bios_hardcoded_edid_size, GFP_KERNEL);
-		if (edid) {
-			memcpy((unsigned char *)edid,
-			       (unsigned char *)rdev->mode_info.bios_hardcoded_edid,
-			       rdev->mode_info.bios_hardcoded_edid_size);
-			return edid;
-		}
-	}
-	return NULL;
+	return drm_edid_duplicate(drm_edid_raw(rdev->mode_info.bios_hardcoded_edid));
 }
 
 static struct radeon_i2c_bus_rec combios_setup_i2c_bus(struct radeon_device *rdev,

drivers/gpu/drm/radeon/radeon_connectors.c

···
 	 */
 	if ((!rdev->is_atom_bios) &&
 	    (ret == connector_status_disconnected) &&
-	    rdev->mode_info.bios_hardcoded_edid_size) {
+	    rdev->mode_info.bios_hardcoded_edid) {
 		ret = connector_status_connected;
 	}
 
···
 out:
 	if ((!rdev->is_atom_bios) &&
 	    (ret == connector_status_disconnected) &&
-	    rdev->mode_info.bios_hardcoded_edid_size) {
+	    rdev->mode_info.bios_hardcoded_edid) {
 		radeon_connector->use_digital = true;
 		ret = connector_status_connected;
 	}

drivers/gpu/drm/radeon/radeon_display.c

···
 		rdev->mode_info.mode_config_initialized = false;
 	}
 
-	kfree(rdev->mode_info.bios_hardcoded_edid);
+	drm_edid_free(rdev->mode_info.bios_hardcoded_edid);
 
 	/* free i2c buses */
 	radeon_i2c_fini(rdev);

drivers/gpu/drm/radeon/radeon_mode.h

···
 #include <linux/i2c-algo-bit.h>
 
 struct edid;
+struct drm_edid;
 struct radeon_bo;
 struct radeon_device;
 
···
 	/* Output CSC */
 	struct drm_property *output_csc_property;
 	/* hardcoded DFP edid from BIOS */
-	struct edid *bios_hardcoded_edid;
-	int bios_hardcoded_edid_size;
+	const struct drm_edid *bios_hardcoded_edid;
 
 	/* firmware flags */
 	u16 firmware_flags;