On 8/12/24 08:23, Jani Nikula wrote:
Instead of just smashing jiffies into a GUID, use guid_gen() to generate
RFC 4122 compliant GUIDs.
Signed-off-by: Jani Nikula <jani.nikula@xxxxxxxxx>
---
Acked-by: Hamza Mahfooz <hamza.mahfooz@xxxxxxx>
I would prefer to take this series through the amdgpu tree though,
assuming nobody minds.
Side note, it baffles me why amdgpu has a copy of this instead of
plumbing it into drm mst code.
---
.../gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 23 ++++++++++---------
1 file changed, 12 insertions(+), 11 deletions(-)
diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
index 72c10fc2c890..ce05e7e2a383 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
@@ -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);
--
Hamza
