[PATCH v7 3/5] media: imx8mq-mipi-csi2: Explicitly release reset

Guoniu Zhou posted 5 patches 3 months, 2 weeks ago
There is a newer version of this series
[PATCH v7 3/5] media: imx8mq-mipi-csi2: Explicitly release reset
Posted by Guoniu Zhou 3 months, 2 weeks ago
From: Guoniu Zhou <guoniu.zhou@nxp.com>

Call reset_control_deassert() to explicitly release reset to make sure
reset bits are cleared since platform like i.MX8ULP can't clear reset
bits automatically.

Reviewed-by: Frank Li <Frank.Li@nxp.com>
Signed-off-by: Guoniu Zhou <guoniu.zhou@nxp.com>
---
 drivers/media/platform/nxp/imx8mq-mipi-csi2.c | 8 ++------
 1 file changed, 2 insertions(+), 6 deletions(-)

diff --git a/drivers/media/platform/nxp/imx8mq-mipi-csi2.c b/drivers/media/platform/nxp/imx8mq-mipi-csi2.c
index fd202601d401145da8be23df4451f6af660642c5..fd788a7f48e5feeff658e3d2347db6fefca5d0cf 100644
--- a/drivers/media/platform/nxp/imx8mq-mipi-csi2.c
+++ b/drivers/media/platform/nxp/imx8mq-mipi-csi2.c
@@ -337,18 +337,14 @@ static int imx8mq_mipi_csi_sw_reset(struct csi_state *state)
 {
 	int ret;
 
-	/*
-	 * these are most likely self-clearing reset bits. to make it
-	 * more clear, the reset-imx7 driver should implement the
-	 * .reset() operation.
-	 */
 	ret = reset_control_assert(state->rst);
 	if (ret < 0) {
 		dev_err(state->dev, "Failed to assert resets: %d\n", ret);
 		return ret;
 	}
 
-	return 0;
+	/* Explicitly release reset to make sure reset bits are cleared. */
+	return reset_control_deassert(state->rst);
 }
 
 static void imx8mq_mipi_csi_set_params(struct csi_state *state)

-- 
2.34.1
Re: [PATCH v7 3/5] media: imx8mq-mipi-csi2: Explicitly release reset
Posted by Laurent Pinchart 3 months, 2 weeks ago
On Thu, Oct 23, 2025 at 05:19:44PM +0800, Guoniu Zhou wrote:
> From: Guoniu Zhou <guoniu.zhou@nxp.com>
> 
> Call reset_control_deassert() to explicitly release reset to make sure
> reset bits are cleared since platform like i.MX8ULP can't clear reset
> bits automatically.
> 
> Reviewed-by: Frank Li <Frank.Li@nxp.com>
> Signed-off-by: Guoniu Zhou <guoniu.zhou@nxp.com>

Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>

> ---
>  drivers/media/platform/nxp/imx8mq-mipi-csi2.c | 8 ++------
>  1 file changed, 2 insertions(+), 6 deletions(-)
> 
> diff --git a/drivers/media/platform/nxp/imx8mq-mipi-csi2.c b/drivers/media/platform/nxp/imx8mq-mipi-csi2.c
> index fd202601d401145da8be23df4451f6af660642c5..fd788a7f48e5feeff658e3d2347db6fefca5d0cf 100644
> --- a/drivers/media/platform/nxp/imx8mq-mipi-csi2.c
> +++ b/drivers/media/platform/nxp/imx8mq-mipi-csi2.c
> @@ -337,18 +337,14 @@ static int imx8mq_mipi_csi_sw_reset(struct csi_state *state)
>  {
>  	int ret;
>  
> -	/*
> -	 * these are most likely self-clearing reset bits. to make it
> -	 * more clear, the reset-imx7 driver should implement the
> -	 * .reset() operation.
> -	 */
>  	ret = reset_control_assert(state->rst);
>  	if (ret < 0) {
>  		dev_err(state->dev, "Failed to assert resets: %d\n", ret);
>  		return ret;
>  	}
>  
> -	return 0;
> +	/* Explicitly release reset to make sure reset bits are cleared. */
> +	return reset_control_deassert(state->rst);
>  }
>  
>  static void imx8mq_mipi_csi_set_params(struct csi_state *state)

-- 
Regards,

Laurent Pinchart