Commit b71ccff6 authored by Jani Nikula's avatar Jani Nikula
Browse files

drm/amd/display: switch to guid_gen() to generate valid GUIDs 



Instead of just smashing jiffies into a GUID, use guid_gen() to generate
RFC 4122 compliant GUIDs.

Reviewed-by: default avatarDaniel Vetter <daniel.vetter@ffwll.ch>
Acked-by: default avatarHarry Wentland <harry.wentland@amd.com>
Acked-by: default avatarAlex Deucher <alexander.deucher@amd.com>
Acked-by: default avatarHamza Mahfooz <hamza.mahfooz@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240812122312.1567046-3-jani.nikula@intel.com


Signed-off-by: default avatarJani Nikula <jani.nikula@intel.com>
parent 4548f10b

drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c

+12 −11
Original line number Diff line number Diff line
@@ -2568,9 +2568,9 @@ static int dm_late_init(void *handle) 


static void resume_mst_branch_status(struct drm_dp_mst_topology_mgr *mgr)

{

	u8 buf[UUID_SIZE];

	guid_t guid;

	int ret;

	u8 guid[16];

	u64 tmp64;



	mutex_lock(&mgr->lock);

	if (!mgr->mst_primary)
@@ -2591,26 +2591,27 @@ static void resume_mst_branch_status(struct drm_dp_mst_topology_mgr *mgr) 
	}



	/* Some hubs forget their guids after they resume */

	ret = drm_dp_dpcd_read(mgr->aux, DP_GUID, guid, 16);

	if (ret != 16) {

	ret = drm_dp_dpcd_read(mgr->aux, DP_GUID, buf, sizeof(buf));

	if (ret != sizeof(buf)) {

		drm_dbg_kms(mgr->dev, "dpcd read failed - undocked during suspend?\n");

		goto out_fail;

	}



	if (memchr_inv(guid, 0, 16) == NULL) {

		tmp64 = get_jiffies_64();

		memcpy(&guid[0], &tmp64, sizeof(u64));

		memcpy(&guid[8], &tmp64, sizeof(u64));

	import_guid(&guid, buf);



		ret = drm_dp_dpcd_write(mgr->aux, DP_GUID, guid, 16);

	if (guid_is_null(&guid)) {

		guid_gen(&guid);

		export_guid(buf, &guid);



		if (ret != 16) {

		ret = drm_dp_dpcd_write(mgr->aux, DP_GUID, buf, sizeof(buf));



		if (ret != sizeof(buf)) {

			drm_dbg_kms(mgr->dev, "check mstb guid failed - undocked during suspend?\n");

			goto out_fail;

		}

	}



	import_guid(&mgr->mst_primary->guid, guid);

	guid_copy(&mgr->mst_primary->guid, &guid);



out_fail:

	mutex_unlock(&mgr->lock);