[PATCH 5/9] media: platform: amd: use refcount_t instead of atomic_t

[Ricardo Ribalda]

We are using the refcnt variable for refcounting. Use the refcount_t
type instead, as it has support for saturation and underflow.

This also makes cocci happier, as it will fix the following warning:
./platform/amd/isp4/isp4_subdev.c:394:6-25: WARNING: atomic_dec_and_test variation before object free at line 395.

Fixes: 4c5feef6a62c ("media: platform: amd: Add isp4 fw and hw interface")
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Ricardo Ribalda <ribalda@xxxxxxxxxxxx>
---
 drivers/media/platform/amd/isp4/isp4_interface.c | 4 ++--
 drivers/media/platform/amd/isp4/isp4_interface.h | 2 +-
 drivers/media/platform/amd/isp4/isp4_subdev.c    | 2 +-
 3 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/media/platform/amd/isp4/isp4_interface.c b/drivers/media/platform/amd/isp4/isp4_interface.c
index 8d73f66bb42c..00a817909292 100644
--- a/drivers/media/platform/amd/isp4/isp4_interface.c
+++ b/drivers/media/platform/amd/isp4/isp4_interface.c
@@ -375,7 +375,7 @@ static int isp4if_send_fw_cmd(struct isp4_interface *ispif, u32 cmd_id,
 			return -ENOMEM;
 
 		/* Get two references: one for the resp thread, one for us */
-		atomic_set(&ele->refcnt, 2);
+		refcount_set(&ele->refcnt, 2);
 		init_completion(&ele->cmd_done);
 	}
 
@@ -455,7 +455,7 @@ static int isp4if_send_fw_cmd(struct isp4_interface *ispif, u32 cmd_id,
 
 put_ele_ref:
 	/* Don't free the command if we didn't put the last reference */
-	if (ele && atomic_dec_return(&ele->refcnt))
+	if (ele && !refcount_dec_and_test(&ele->refcnt))
 		ele = NULL;
 
 free_ele:
diff --git a/drivers/media/platform/amd/isp4/isp4_interface.h b/drivers/media/platform/amd/isp4/isp4_interface.h
index ce3ac9b9e5cd..04db71cd54e6 100644
--- a/drivers/media/platform/amd/isp4/isp4_interface.h
+++ b/drivers/media/platform/amd/isp4/isp4_interface.h
@@ -68,7 +68,7 @@ struct isp4if_cmd_element {
 	u32 seq_num;
 	u32 cmd_id;
 	struct completion cmd_done;
-	atomic_t refcnt;
+	refcount_t refcnt;
 };
 
 struct isp4_interface {
diff --git a/drivers/media/platform/amd/isp4/isp4_subdev.c b/drivers/media/platform/amd/isp4/isp4_subdev.c
index 48deea79ce6c..2a8bc1207843 100644
--- a/drivers/media/platform/amd/isp4/isp4_subdev.c
+++ b/drivers/media/platform/amd/isp4/isp4_subdev.c
@@ -391,7 +391,7 @@ static void isp4sd_fw_resp_cmd_done(struct isp4_subdev *isp_subdev,
 
 	if (ele) {
 		complete(&ele->cmd_done);
-		if (atomic_dec_and_test(&ele->refcnt))
+		if (refcount_dec_and_test(&ele->refcnt))
 			kfree(ele);
 	}
 }

-- 
2.55.0.rc0.799.gd6f94ed593-goog