[PATCH v3 05/12] media: staging: rkisp1: params: set vb.sequence to be the isp's frame_sequence + 1

[Dafna Hirschfeld]

The params isr is called when the ISP finishes processing a frame
(RKISP1_CIF_ISP_FRAME). Configurations performed in the params isr
will be applied on the next frame. Since frame_sequence is updated
on the vertical sync signal, we should use frame_sequence + 1 as
the vb.sequence of the params buffer to indicate to userspace on
which frame these parameters are being applied.

Signed-off-by: Dafna Hirschfeld <dafna.hirschfeld at collabora.com>
Acked-by: Helen Koike <helen.koike at collabora.com>
---
changes since v2:
rephrase commit message and inline doc as suggested by Helen.
---
 drivers/staging/media/rkisp1/rkisp1-params.c | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/drivers/staging/media/rkisp1/rkisp1-params.c b/drivers/staging/media/rkisp1/rkisp1-params.c
index e8049a50575f..24a49368df22 100644
--- a/drivers/staging/media/rkisp1/rkisp1-params.c
+++ b/drivers/staging/media/rkisp1/rkisp1-params.c
@@ -1213,7 +1213,14 @@ static void rkisp1_params_apply_params_cfg(struct rkisp1_params *params,
 
 void rkisp1_params_isr(struct rkisp1_device *rkisp1)
 {
-	unsigned int frame_sequence = atomic_read(&rkisp1->isp.frame_sequence);
+	/*
+	 * This isr is called when the ISR finishes processing a frame (RKISP1_CIF_ISP_FRAME).
+	 * Configurations performed here will be applied on the next frame.
+	 * Since frame_sequence is updated on the vertical sync signal, we should use
+	 * frame_sequence + 1 here to indicate to userspace on which frame these parameters
+	 * are being applied.
+	 */
+	unsigned int frame_sequence = atomic_read(&rkisp1->isp.frame_sequence) + 1;
 	struct rkisp1_params *params = &rkisp1->params;
 
 	spin_lock(&params->config_lock);
-- 
2.17.1