diff mbox series

[2/2] media: imx: imx-mipi-csis: Drop powered flag

Message ID 20220312152505.145453-2-jacopo@jmondi.org (mailing list archive)
State New, archived
Headers show
Series None | expand

Commit Message

Jacopo Mondi March 12, 2022, 3:25 p.m. UTC 
The mipi_csis_device.powered flag only serves for the purpose of
not accessing registers in mipi_csis_log_status() when the interface
is not powered up.

Instead of manually tracking the power state, rely on
pm_runtime_get_if_in_use() and remove the flag.

Signed-off-by: Jacopo Mondi <jacopo@jmondi.org>
---
 drivers/media/platform/imx/imx-mipi-csis.c | 18 ++++++++++--------
 1 file changed, 10 insertions(+), 8 deletions(-)

--
2.35.1

Comments

Laurent Pinchart March 12, 2022, 6:50 p.m. UTC | #1 
Hi Jacopo,

Thank you for the patch.

On Sat, Mar 12, 2022 at 04:25:05PM +0100, Jacopo Mondi wrote:
> The mipi_csis_device.powered flag only serves for the purpose of
> not accessing registers in mipi_csis_log_status() when the interface
> is not powered up.
> 
> Instead of manually tracking the power state, rely on
> pm_runtime_get_if_in_use() and remove the flag.
> 
> Signed-off-by: Jacopo Mondi <jacopo@jmondi.org>
> ---
>  drivers/media/platform/imx/imx-mipi-csis.c | 18 ++++++++++--------
>  1 file changed, 10 insertions(+), 8 deletions(-)
> 
> diff --git a/drivers/media/platform/imx/imx-mipi-csis.c b/drivers/media/platform/imx/imx-mipi-csis.c
> index fa00b36fc394..505dd373b40c 100644
> --- a/drivers/media/platform/imx/imx-mipi-csis.c
> +++ b/drivers/media/platform/imx/imx-mipi-csis.c
> @@ -327,10 +327,9 @@ struct mipi_csis_device {
>  	u32 hs_settle;
>  	u32 clk_settle;
> 
> -	struct mutex lock;	/* Protect csis_fmt, format_mbus and powered */
> +	struct mutex lock;	/* Protect csis_fmt and format_mbus */
>  	const struct csis_pix_format *csis_fmt;
>  	struct v4l2_mbus_framefmt format_mbus[CSIS_PADS_NUM];
> -	bool powered;
> 
>  	spinlock_t slock;	/* Protect events */
>  	struct mipi_csis_event events[MIPI_CSIS_NUM_EVENTS];
> @@ -1176,8 +1175,15 @@ static int mipi_csis_log_status(struct v4l2_subdev *sd)
> 
>  	mutex_lock(&csis->lock);
>  	mipi_csis_log_counters(csis, true);
> -	if (csis->debug.enable && csis->powered)
> -		mipi_csis_dump_regs(csis);
> +	if (!csis->debug.enable ||
> +	    !pm_runtime_get_if_in_use(csis->dev))
> +		goto unlock;
> +
> +	mipi_csis_dump_regs(csis);
> +
> +	pm_runtime_put(csis->dev);
> +
> +unlock:

I like this change, but I think we can go one step further and drop the
lock here, as there's no powered field to access anymore:

	struct mipi_csis_device *csis = sd_to_mipi_csis_device(sd);

	mipi_csis_log_counters(csis, true);

	if (csis->debug.enable && pm_runtime_get_if_in_use(csi->dev)) {
		mipi_csis_dump_regs(csis);
		pm_runtime_put(csis->dev);
	}

	return 0;

A third patch could then drop the lock from mipi_csis_runtime_suspend()
and mipi_csis_runtime_resume(). What do you think ?

>  	mutex_unlock(&csis->lock);
> 
>  	return 0;
> @@ -1344,8 +1350,6 @@ static int __maybe_unused mipi_csis_runtime_suspend(struct device *dev)
> 
>  	mipi_csis_clk_disable(csis);
> 
> -	csis->powered = false;
> -
>  unlock:
>  	mutex_unlock(&csis->lock);
> 
> @@ -1366,8 +1370,6 @@ static int __maybe_unused mipi_csis_runtime_resume(struct device *dev)
> 
>  	mipi_csis_clk_enable(csis);
> 
> -	csis->powered = true;
> -
>  unlock:
>  	mutex_unlock(&csis->lock);
>
diff mbox series

Patch

diff --git a/drivers/media/platform/imx/imx-mipi-csis.c b/drivers/media/platform/imx/imx-mipi-csis.c
index fa00b36fc394..505dd373b40c 100644
--- a/drivers/media/platform/imx/imx-mipi-csis.c
+++ b/drivers/media/platform/imx/imx-mipi-csis.c
@@ -327,10 +327,9 @@  struct mipi_csis_device {
 	u32 hs_settle;
 	u32 clk_settle;

-	struct mutex lock;	/* Protect csis_fmt, format_mbus and powered */
+	struct mutex lock;	/* Protect csis_fmt and format_mbus */
 	const struct csis_pix_format *csis_fmt;
 	struct v4l2_mbus_framefmt format_mbus[CSIS_PADS_NUM];
-	bool powered;

 	spinlock_t slock;	/* Protect events */
 	struct mipi_csis_event events[MIPI_CSIS_NUM_EVENTS];
@@ -1176,8 +1175,15 @@  static int mipi_csis_log_status(struct v4l2_subdev *sd)

 	mutex_lock(&csis->lock);
 	mipi_csis_log_counters(csis, true);
-	if (csis->debug.enable && csis->powered)
-		mipi_csis_dump_regs(csis);
+	if (!csis->debug.enable ||
+	    !pm_runtime_get_if_in_use(csis->dev))
+		goto unlock;
+
+	mipi_csis_dump_regs(csis);
+
+	pm_runtime_put(csis->dev);
+
+unlock:
 	mutex_unlock(&csis->lock);

 	return 0;
@@ -1344,8 +1350,6 @@  static int __maybe_unused mipi_csis_runtime_suspend(struct device *dev)

 	mipi_csis_clk_disable(csis);

-	csis->powered = false;
-
 unlock:
 	mutex_unlock(&csis->lock);

@@ -1366,8 +1370,6 @@  static int __maybe_unused mipi_csis_runtime_resume(struct device *dev)

 	mipi_csis_clk_enable(csis);

-	csis->powered = true;
-
 unlock:
 	mutex_unlock(&csis->lock);