[PATCH] drm/xe: Restore EIO errno return when GuC PC start fails

[Rodrigo Vivi <rodrigo.vivi@intel.com>]

Commit b4b05e53b550 ("drm/xe/guc_pc: Retry and wait longer for GuC PC
start") from Mar 7, 2025 (linux-next), leads to the following Smatch
static checker warning:

        drivers/gpu/drm/xe/xe_guc_pc.c:1073 xe_guc_pc_start()
        warn: missing error code here? '_dev_err()' failed. 'ret' = '0'

Fixes: b4b05e53b550 ("drm/xe/guc_pc: Retry and wait longer for GuC PC start")
Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
Closes: https://lore.kernel.org/intel-xe/1454a5f1-ee18-4df1-a6b2-a4a3dddcd1cb@stanley.mountain/
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
---
 drivers/gpu/drm/xe/xe_guc_pc.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/gpu/drm/xe/xe_guc_pc.c b/drivers/gpu/drm/xe/xe_guc_pc.c
index 85215313976c..43b1192ba61c 100644
--- a/drivers/gpu/drm/xe/xe_guc_pc.c
+++ b/drivers/gpu/drm/xe/xe_guc_pc.c
@@ -1070,6 +1070,7 @@ int xe_guc_pc_start(struct xe_guc_pc *pc)
 		if (wait_for_pc_state(pc, SLPC_GLOBAL_STATE_RUNNING,
 				      SLPC_RESET_EXTENDED_TIMEOUT_MS)) {
 			xe_gt_err(gt, "GuC PC Start failed: Dynamic GT frequency control and GT sleep states are now disabled.\n");
+			ret = -EIO;
 			goto out;
 		}
 
-- 
2.49.0