diff mbox series

[v4,08/79] media: atmel: properly get pm_runtime

Message ID 3150349be99187c4f9290ac35d6227bb6a83519b.1619621413.git.mchehab+huawei@kernel.org
State Superseded
Headers show
Series Address some issues with PM runtime at media subsystem | expand

Commit Message

Mauro Carvalho Chehab April 28, 2021, 2:51 p.m. UTC
There are several issues in the way the atmel driver handles
pm_runtime_get_sync():

- it doesn't check return codes;
- it doesn't properly decrement the usage_count on all places;
- it starts streaming even if pm_runtime_get_sync() fails.
- while it tries to get pm_runtime at the clock enable logic,
  it doesn't check if the operation was suceeded.

Replace all occurrences of it to use the new kAPI:
pm_runtime_resume_and_get(), which ensures that, if the
return code is not negative, the usage_count was incremented.

With that, add additional checks when this is called, in order
to ensure that errors will be properly addressed.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
---
 drivers/media/platform/atmel/atmel-isc-base.c | 27 ++++++++++++++-----
 drivers/media/platform/atmel/atmel-isi.c      | 19 ++++++++++---
 2 files changed, 35 insertions(+), 11 deletions(-)

Comments

Jonathan Cameron April 30, 2021, 4:13 p.m. UTC | #1
On Wed, 28 Apr 2021 16:51:29 +0200
Mauro Carvalho Chehab <mchehab+huawei@kernel.org> wrote:

> There are several issues in the way the atmel driver handles

> pm_runtime_get_sync():

> 

> - it doesn't check return codes;

> - it doesn't properly decrement the usage_count on all places;

> - it starts streaming even if pm_runtime_get_sync() fails.

> - while it tries to get pm_runtime at the clock enable logic,

>   it doesn't check if the operation was suceeded.

> 

> Replace all occurrences of it to use the new kAPI:

> pm_runtime_resume_and_get(), which ensures that, if the

> return code is not negative, the usage_count was incremented.

> 

> With that, add additional checks when this is called, in order

> to ensure that errors will be properly addressed.

> 

> Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

> ---

>  drivers/media/platform/atmel/atmel-isc-base.c | 27 ++++++++++++++-----

>  drivers/media/platform/atmel/atmel-isi.c      | 19 ++++++++++---

>  2 files changed, 35 insertions(+), 11 deletions(-)

> 

> diff --git a/drivers/media/platform/atmel/atmel-isc-base.c b/drivers/media/platform/atmel/atmel-isc-base.c

> index fe3ec8d0eaee..02543fe42e9d 100644

> --- a/drivers/media/platform/atmel/atmel-isc-base.c

> +++ b/drivers/media/platform/atmel/atmel-isc-base.c

> @@ -294,9 +294,13 @@ static int isc_wait_clk_stable(struct clk_hw *hw)

>  static int isc_clk_prepare(struct clk_hw *hw)

>  {

>  	struct isc_clk *isc_clk = to_isc_clk(hw);

> +	int ret;

>  

> -	if (isc_clk->id == ISC_ISPCK)

> -		pm_runtime_get_sync(isc_clk->dev);

> +	if (isc_clk->id == ISC_ISPCK) {

> +		ret = pm_runtime_resume_and_get(isc_clk->dev);

> +		if (ret < 0)

> +			return 0;


Why not the error?  isc_wait_clk_stable() is happy to return -ETIMEDOUT so I
assume the callers should fine with errors.

> +	}

>  

>  	return isc_wait_clk_stable(hw);

>  }

> @@ -353,9 +357,13 @@ static int isc_clk_is_enabled(struct clk_hw *hw)

>  {

>  	struct isc_clk *isc_clk = to_isc_clk(hw);

>  	u32 status;

> +	int ret;

>  

> -	if (isc_clk->id == ISC_ISPCK)

> -		pm_runtime_get_sync(isc_clk->dev);

> +	if (isc_clk->id == ISC_ISPCK) {

> +		ret = pm_runtime_resume_and_get(isc_clk->dev);

> +		if (ret < 0)

> +			return 0;

> +	}

>  

>  	regmap_read(isc_clk->regmap, ISC_CLKSR, &status);

>  

> @@ -807,7 +815,9 @@ static int isc_start_streaming(struct vb2_queue *vq, unsigned int count)

>  		goto err_start_stream;

>  	}

>  

> -	pm_runtime_get_sync(isc->dev);

> +	ret = pm_runtime_resume_and_get(isc->dev);

> +	if (ret < 0)

> +		goto err_pm_get;

>  

>  	ret = isc_configure(isc);

>  	if (unlikely(ret))

> @@ -838,7 +848,7 @@ static int isc_start_streaming(struct vb2_queue *vq, unsigned int count)

>  

>  err_configure:

>  	pm_runtime_put_sync(isc->dev);

> -

> +err_pm_get:

>  	v4l2_subdev_call(isc->current_subdev->sd, video, s_stream, 0);

>  

>  err_start_stream:

> @@ -1809,6 +1819,7 @@ static void isc_awb_work(struct work_struct *w)

>  	u32 baysel;

>  	unsigned long flags;

>  	u32 min, max;

> +	int ret;

>  

>  	/* streaming is not active anymore */

>  	if (isc->stop)

> @@ -1831,7 +1842,9 @@ static void isc_awb_work(struct work_struct *w)

>  	ctrls->hist_id = hist_id;

>  	baysel = isc->config.sd_format->cfa_baycfg << ISC_HIS_CFG_BAYSEL_SHIFT;

>  

> -	pm_runtime_get_sync(isc->dev);

> +	ret = pm_runtime_resume_and_get(isc->dev);

> +	if (ret < 0)


Maybe warn or similar?

> +		return;

>  

>  	/*

>  	 * only update if we have all the required histograms and controls

> diff --git a/drivers/media/platform/atmel/atmel-isi.c b/drivers/media/platform/atmel/atmel-isi.c

> index 0514be6153df..6a433926726d 100644

> --- a/drivers/media/platform/atmel/atmel-isi.c

> +++ b/drivers/media/platform/atmel/atmel-isi.c

> @@ -422,7 +422,9 @@ static int start_streaming(struct vb2_queue *vq, unsigned int count)

>  	struct frame_buffer *buf, *node;

>  	int ret;

>  

> -	pm_runtime_get_sync(isi->dev);

> +	ret = pm_runtime_resume_and_get(isi->dev);

> +	if (ret < 0)

> +		return ret;

>  

>  	/* Enable stream on the sub device */

>  	ret = v4l2_subdev_call(isi->entity.subdev, video, s_stream, 1);

> @@ -782,9 +784,10 @@ static int isi_enum_frameintervals(struct file *file, void *fh,

>  	return 0;

>  }

>  

> -static void isi_camera_set_bus_param(struct atmel_isi *isi)

> +static int isi_camera_set_bus_param(struct atmel_isi *isi)

>  {

>  	u32 cfg1 = 0;

> +	int ret;

>  

>  	/* set bus param for ISI */

>  	if (isi->pdata.hsync_act_low)

> @@ -801,12 +804,16 @@ static void isi_camera_set_bus_param(struct atmel_isi *isi)

>  	cfg1 |= ISI_CFG1_THMASK_BEATS_16;

>  

>  	/* Enable PM and peripheral clock before operate isi registers */

> -	pm_runtime_get_sync(isi->dev);

> +	ret = pm_runtime_resume_and_get(isi->dev);

> +	if (ret < 0)

> +		return ret;

>  

>  	isi_writel(isi, ISI_CTRL, ISI_CTRL_DIS);

>  	isi_writel(isi, ISI_CFG1, cfg1);

>  

>  	pm_runtime_put(isi->dev);

> +

> +	return 0;

>  }

>  

>  /* -----------------------------------------------------------------------*/

> @@ -1085,7 +1092,11 @@ static int isi_graph_notify_complete(struct v4l2_async_notifier *notifier)

>  		dev_err(isi->dev, "No supported mediabus format found\n");

>  		return ret;

>  	}

> -	isi_camera_set_bus_param(isi);

> +	ret = isi_camera_set_bus_param(isi);

> +	if (ret) {

> +		dev_err(isi->dev, "Can't wake up device\n");

> +		return ret;

> +	}

>  

>  	ret = isi_set_default_fmt(isi);

>  	if (ret) {
diff mbox series

Patch

diff --git a/drivers/media/platform/atmel/atmel-isc-base.c b/drivers/media/platform/atmel/atmel-isc-base.c
index fe3ec8d0eaee..02543fe42e9d 100644
--- a/drivers/media/platform/atmel/atmel-isc-base.c
+++ b/drivers/media/platform/atmel/atmel-isc-base.c
@@ -294,9 +294,13 @@  static int isc_wait_clk_stable(struct clk_hw *hw)
 static int isc_clk_prepare(struct clk_hw *hw)
 {
 	struct isc_clk *isc_clk = to_isc_clk(hw);
+	int ret;
 
-	if (isc_clk->id == ISC_ISPCK)
-		pm_runtime_get_sync(isc_clk->dev);
+	if (isc_clk->id == ISC_ISPCK) {
+		ret = pm_runtime_resume_and_get(isc_clk->dev);
+		if (ret < 0)
+			return 0;
+	}
 
 	return isc_wait_clk_stable(hw);
 }
@@ -353,9 +357,13 @@  static int isc_clk_is_enabled(struct clk_hw *hw)
 {
 	struct isc_clk *isc_clk = to_isc_clk(hw);
 	u32 status;
+	int ret;
 
-	if (isc_clk->id == ISC_ISPCK)
-		pm_runtime_get_sync(isc_clk->dev);
+	if (isc_clk->id == ISC_ISPCK) {
+		ret = pm_runtime_resume_and_get(isc_clk->dev);
+		if (ret < 0)
+			return 0;
+	}
 
 	regmap_read(isc_clk->regmap, ISC_CLKSR, &status);
 
@@ -807,7 +815,9 @@  static int isc_start_streaming(struct vb2_queue *vq, unsigned int count)
 		goto err_start_stream;
 	}
 
-	pm_runtime_get_sync(isc->dev);
+	ret = pm_runtime_resume_and_get(isc->dev);
+	if (ret < 0)
+		goto err_pm_get;
 
 	ret = isc_configure(isc);
 	if (unlikely(ret))
@@ -838,7 +848,7 @@  static int isc_start_streaming(struct vb2_queue *vq, unsigned int count)
 
 err_configure:
 	pm_runtime_put_sync(isc->dev);
-
+err_pm_get:
 	v4l2_subdev_call(isc->current_subdev->sd, video, s_stream, 0);
 
 err_start_stream:
@@ -1809,6 +1819,7 @@  static void isc_awb_work(struct work_struct *w)
 	u32 baysel;
 	unsigned long flags;
 	u32 min, max;
+	int ret;
 
 	/* streaming is not active anymore */
 	if (isc->stop)
@@ -1831,7 +1842,9 @@  static void isc_awb_work(struct work_struct *w)
 	ctrls->hist_id = hist_id;
 	baysel = isc->config.sd_format->cfa_baycfg << ISC_HIS_CFG_BAYSEL_SHIFT;
 
-	pm_runtime_get_sync(isc->dev);
+	ret = pm_runtime_resume_and_get(isc->dev);
+	if (ret < 0)
+		return;
 
 	/*
 	 * only update if we have all the required histograms and controls
diff --git a/drivers/media/platform/atmel/atmel-isi.c b/drivers/media/platform/atmel/atmel-isi.c
index 0514be6153df..6a433926726d 100644
--- a/drivers/media/platform/atmel/atmel-isi.c
+++ b/drivers/media/platform/atmel/atmel-isi.c
@@ -422,7 +422,9 @@  static int start_streaming(struct vb2_queue *vq, unsigned int count)
 	struct frame_buffer *buf, *node;
 	int ret;
 
-	pm_runtime_get_sync(isi->dev);
+	ret = pm_runtime_resume_and_get(isi->dev);
+	if (ret < 0)
+		return ret;
 
 	/* Enable stream on the sub device */
 	ret = v4l2_subdev_call(isi->entity.subdev, video, s_stream, 1);
@@ -782,9 +784,10 @@  static int isi_enum_frameintervals(struct file *file, void *fh,
 	return 0;
 }
 
-static void isi_camera_set_bus_param(struct atmel_isi *isi)
+static int isi_camera_set_bus_param(struct atmel_isi *isi)
 {
 	u32 cfg1 = 0;
+	int ret;
 
 	/* set bus param for ISI */
 	if (isi->pdata.hsync_act_low)
@@ -801,12 +804,16 @@  static void isi_camera_set_bus_param(struct atmel_isi *isi)
 	cfg1 |= ISI_CFG1_THMASK_BEATS_16;
 
 	/* Enable PM and peripheral clock before operate isi registers */
-	pm_runtime_get_sync(isi->dev);
+	ret = pm_runtime_resume_and_get(isi->dev);
+	if (ret < 0)
+		return ret;
 
 	isi_writel(isi, ISI_CTRL, ISI_CTRL_DIS);
 	isi_writel(isi, ISI_CFG1, cfg1);
 
 	pm_runtime_put(isi->dev);
+
+	return 0;
 }
 
 /* -----------------------------------------------------------------------*/
@@ -1085,7 +1092,11 @@  static int isi_graph_notify_complete(struct v4l2_async_notifier *notifier)
 		dev_err(isi->dev, "No supported mediabus format found\n");
 		return ret;
 	}
-	isi_camera_set_bus_param(isi);
+	ret = isi_camera_set_bus_param(isi);
+	if (ret) {
+		dev_err(isi->dev, "Can't wake up device\n");
+		return ret;
+	}
 
 	ret = isi_set_default_fmt(isi);
 	if (ret) {