[PATCH v1] drm/xe: Don't fail probe on unsupported mailbox command

[Raag Jadav]

If the device is running older pcode firmware, it is possible that
newer mailbox commands are not supported by it. The sysfs attributes
aren't useful in that case but we shouldn't fail probe because it.

Fixes: cdc36b66cd41 ("drm/xe: Expose fan control and voltage regulator version")
Signed-off-by: Raag Jadav <raag.jadav at intel.com>
---
 drivers/gpu/drm/xe/xe_device_sysfs.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/xe/xe_device_sysfs.c b/drivers/gpu/drm/xe/xe_device_sysfs.c
index 8250aa4620ee..654a1ba92311 100644
--- a/drivers/gpu/drm/xe/xe_device_sysfs.c
+++ b/drivers/gpu/drm/xe/xe_device_sysfs.c
@@ -160,8 +160,13 @@ static int late_bind_create_files(struct device *dev)
 
 	ret = xe_pcode_read(root, PCODE_MBOX(PCODE_LATE_BINDING, GET_CAPABILITY_STATUS, 0),
 			    &cap, NULL);
-	if (ret)
+	if (ret) {
+		/* Don't fail probe on older pcode firmware which might not support this command. */
+		if (ret == -ENXIO)
+			ret = 0;
+
 		goto out;
+	}
 
 	if (REG_FIELD_GET(V1_FAN_SUPPORTED, cap)) {
 		ret = sysfs_create_file(&dev->kobj, &dev_attr_lb_fan_control_version.attr);
-- 
2.34.1