LinuxTV Patchwork [v3,03/14] media: ov7670: hook s_power onto v4l2 core

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Submitter Lubomir Rintel
Date Nov. 20, 2018, 10:03 a.m.
Message ID <20181120100318.367987-4-lkundrak@v3.sk>
Download mbox | patch
Permalink /patch/53038/
State New
Delegated to: Sakari Ailus
Headers show

Comments

Lubomir Rintel - Nov. 20, 2018, 10:03 a.m.
The commit 71862f63f351 ("media: ov7670: Add the ov7670_s_power function")
added a power control routing. However, it was not good enough to use as
a s_power() callback: it merely flipped on the power GPIOs without
restoring the register settings.

Fix this now and register an actual power callback.

Signed-off-by: Lubomir Rintel <lkundrak@v3.sk>

---
Changes since v2:
- Restore the controls, format and frame rate on power on

 drivers/media/i2c/ov7670.c | 50 +++++++++++++++++++++++++++++++++-----
 1 file changed, 44 insertions(+), 6 deletions(-)
Sakari Ailus - Nov. 22, 2018, 12:21 p.m.
Hi Lubomir,

On Tue, Nov 20, 2018 at 11:03:08AM +0100, Lubomir Rintel wrote:
> The commit 71862f63f351 ("media: ov7670: Add the ov7670_s_power function")
> added a power control routing. However, it was not good enough to use as
> a s_power() callback: it merely flipped on the power GPIOs without
> restoring the register settings.
> 
> Fix this now and register an actual power callback.
> 
> Signed-off-by: Lubomir Rintel <lkundrak@v3.sk>
> 
> ---
> Changes since v2:
> - Restore the controls, format and frame rate on power on
> 
>  drivers/media/i2c/ov7670.c | 50 +++++++++++++++++++++++++++++++++-----
>  1 file changed, 44 insertions(+), 6 deletions(-)
> 
> diff --git a/drivers/media/i2c/ov7670.c b/drivers/media/i2c/ov7670.c
> index ead0c360df33..cbaab60aaaac 100644
> --- a/drivers/media/i2c/ov7670.c
> +++ b/drivers/media/i2c/ov7670.c
> @@ -242,6 +242,7 @@ struct ov7670_info {
>  	struct ov7670_format_struct *fmt;  /* Current format */
>  	struct ov7670_win_size *wsize;
>  	struct clk *clk;
> +	int on;
>  	struct gpio_desc *resetb_gpio;
>  	struct gpio_desc *pwdn_gpio;
>  	unsigned int mbus_config;	/* Media bus configuration flags */
> @@ -1615,19 +1616,54 @@ static int ov7670_s_register(struct v4l2_subdev *sd, const struct v4l2_dbg_regis
>  }
>  #endif
>  
> -static int ov7670_s_power(struct v4l2_subdev *sd, int on)
> +static void ov7670_power_on(struct v4l2_subdev *sd)
>  {
>  	struct ov7670_info *info = to_state(sd);
>  
> +	if (info->on)
> +		return;
> +
>  	if (info->pwdn_gpio)
> -		gpiod_set_value(info->pwdn_gpio, !on);
> -	if (on && info->resetb_gpio) {
> +		gpiod_set_value(info->pwdn_gpio, 0);
> +	if (info->resetb_gpio) {
>  		gpiod_set_value(info->resetb_gpio, 1);
>  		usleep_range(500, 1000);
>  		gpiod_set_value(info->resetb_gpio, 0);
>  		usleep_range(3000, 5000);
>  	}
>  
> +	info->on = true;
> +}
> +
> +static void ov7670_power_off(struct v4l2_subdev *sd)
> +{
> +	struct ov7670_info *info = to_state(sd);
> +
> +	if (!info->on)
> +		return;
> +
> +	if (info->pwdn_gpio)
> +		gpiod_set_value(info->pwdn_gpio, 1);
> +
> +	info->on = false;
> +}
> +
> +static int ov7670_s_power(struct v4l2_subdev *sd, int on)
> +{
> +	struct ov7670_info *info = to_state(sd);
> +
> +	if (info->on == on)
> +		return 0;
> +
> +	if (on) {
> +		ov7670_power_on (sd);
> +		ov7670_apply_fmt(sd);
> +		ov7675_apply_framerate(sd);
> +		v4l2_ctrl_handler_setup(&info->hdl);
> +	} else {
> +		ov7670_power_off (sd);
> +	}
> +
>  	return 0;
>  }
>  
> @@ -1660,6 +1696,7 @@ static int ov7670_open(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh)
>  static const struct v4l2_subdev_core_ops ov7670_core_ops = {
>  	.reset = ov7670_reset,
>  	.init = ov7670_init,
> +	.s_power = ov7670_s_power,
>  #ifdef CONFIG_VIDEO_ADV_DEBUG
>  	.g_register = ov7670_g_register,
>  	.s_register = ov7670_s_register,
> @@ -1825,6 +1862,7 @@ static int ov7670_probe(struct i2c_client *client,
>  		else
>  			return ret;
>  	}
> +
>  	if (info->clk) {
>  		ret = clk_prepare_enable(info->clk);
>  		if (ret)
> @@ -1841,7 +1879,7 @@ static int ov7670_probe(struct i2c_client *client,
>  	if (ret)
>  		goto clk_disable;
>  
> -	ov7670_s_power(sd, 1);
> +	ov7670_power_on(sd);
>  
>  	/* Make sure it's an ov7670 */
>  	ret = ov7670_detect(sd);
> @@ -1929,7 +1967,7 @@ static int ov7670_probe(struct i2c_client *client,
>  hdl_free:
>  	v4l2_ctrl_handler_free(&info->hdl);
>  power_off:
> -	ov7670_s_power(sd, 0);
> +	ov7670_power_off(sd);
>  clk_disable:
>  	clk_disable_unprepare(info->clk);
>  	return ret;
> @@ -1945,7 +1983,7 @@ static int ov7670_remove(struct i2c_client *client)
>  	v4l2_ctrl_handler_free(&info->hdl);
>  	clk_disable_unprepare(info->clk);
>  	media_entity_cleanup(&info->sd.entity);
> -	ov7670_s_power(sd, 0);
> +	ov7670_power_off(sd);
>  	return 0;
>  }
>  

Could you consider instead switching to runtime PM? A few drivers such as
the ov2685 driver does that already.
Lubomir Rintel - Nov. 28, 2018, 11:29 a.m.
On Thu, 2018-11-22 at 14:21 +0200, Sakari Ailus wrote:
> Hi Lubomir,
> 
> On Tue, Nov 20, 2018 at 11:03:08AM +0100, Lubomir Rintel wrote:
> > The commit 71862f63f351 ("media: ov7670: Add the ov7670_s_power function")
> > added a power control routing. However, it was not good enough to use as
> > a s_power() callback: it merely flipped on the power GPIOs without
> > restoring the register settings.
> > 
> > Fix this now and register an actual power callback.
> > 
> > Signed-off-by: Lubomir Rintel <lkundrak@v3.sk>
> > 
> > ---
> > Changes since v2:
> > - Restore the controls, format and frame rate on power on
> > 
> >  drivers/media/i2c/ov7670.c | 50 +++++++++++++++++++++++++++++++++-----
> >  1 file changed, 44 insertions(+), 6 deletions(-)
> > 
> > diff --git a/drivers/media/i2c/ov7670.c b/drivers/media/i2c/ov7670.c
> > index ead0c360df33..cbaab60aaaac 100644
> > --- a/drivers/media/i2c/ov7670.c
> > +++ b/drivers/media/i2c/ov7670.c
> > @@ -242,6 +242,7 @@ struct ov7670_info {
> >  	struct ov7670_format_struct *fmt;  /* Current format */
> >  	struct ov7670_win_size *wsize;
> >  	struct clk *clk;
> > +	int on;
> >  	struct gpio_desc *resetb_gpio;
> >  	struct gpio_desc *pwdn_gpio;
> >  	unsigned int mbus_config;	/* Media bus configuration flags */
> > @@ -1615,19 +1616,54 @@ static int ov7670_s_register(struct v4l2_subdev *sd, const struct v4l2_dbg_regis
> >  }
> >  #endif
> >  
> > -static int ov7670_s_power(struct v4l2_subdev *sd, int on)
> > +static void ov7670_power_on(struct v4l2_subdev *sd)
> >  {
> >  	struct ov7670_info *info = to_state(sd);
> >  
> > +	if (info->on)
> > +		return;
> > +
> >  	if (info->pwdn_gpio)
> > -		gpiod_set_value(info->pwdn_gpio, !on);
> > -	if (on && info->resetb_gpio) {
> > +		gpiod_set_value(info->pwdn_gpio, 0);
> > +	if (info->resetb_gpio) {
> >  		gpiod_set_value(info->resetb_gpio, 1);
> >  		usleep_range(500, 1000);
> >  		gpiod_set_value(info->resetb_gpio, 0);
> >  		usleep_range(3000, 5000);
> >  	}
> >  
> > +	info->on = true;
> > +}
> > +
> > +static void ov7670_power_off(struct v4l2_subdev *sd)
> > +{
> > +	struct ov7670_info *info = to_state(sd);
> > +
> > +	if (!info->on)
> > +		return;
> > +
> > +	if (info->pwdn_gpio)
> > +		gpiod_set_value(info->pwdn_gpio, 1);
> > +
> > +	info->on = false;
> > +}
> > +
> > +static int ov7670_s_power(struct v4l2_subdev *sd, int on)
> > +{
> > +	struct ov7670_info *info = to_state(sd);
> > +
> > +	if (info->on == on)
> > +		return 0;
> > +
> > +	if (on) {
> > +		ov7670_power_on (sd);
> > +		ov7670_apply_fmt(sd);
> > +		ov7675_apply_framerate(sd);
> > +		v4l2_ctrl_handler_setup(&info->hdl);
> > +	} else {
> > +		ov7670_power_off (sd);
> > +	}
> > +
> >  	return 0;
> >  }
> >  
> > @@ -1660,6 +1696,7 @@ static int ov7670_open(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh)
> >  static const struct v4l2_subdev_core_ops ov7670_core_ops = {
> >  	.reset = ov7670_reset,
> >  	.init = ov7670_init,
> > +	.s_power = ov7670_s_power,
> >  #ifdef CONFIG_VIDEO_ADV_DEBUG
> >  	.g_register = ov7670_g_register,
> >  	.s_register = ov7670_s_register,
> > @@ -1825,6 +1862,7 @@ static int ov7670_probe(struct i2c_client *client,
> >  		else
> >  			return ret;
> >  	}
> > +
> >  	if (info->clk) {
> >  		ret = clk_prepare_enable(info->clk);
> >  		if (ret)
> > @@ -1841,7 +1879,7 @@ static int ov7670_probe(struct i2c_client *client,
> >  	if (ret)
> >  		goto clk_disable;
> >  
> > -	ov7670_s_power(sd, 1);
> > +	ov7670_power_on(sd);
> >  
> >  	/* Make sure it's an ov7670 */
> >  	ret = ov7670_detect(sd);
> > @@ -1929,7 +1967,7 @@ static int ov7670_probe(struct i2c_client *client,
> >  hdl_free:
> >  	v4l2_ctrl_handler_free(&info->hdl);
> >  power_off:
> > -	ov7670_s_power(sd, 0);
> > +	ov7670_power_off(sd);
> >  clk_disable:
> >  	clk_disable_unprepare(info->clk);
> >  	return ret;
> > @@ -1945,7 +1983,7 @@ static int ov7670_remove(struct i2c_client *client)
> >  	v4l2_ctrl_handler_free(&info->hdl);
> >  	clk_disable_unprepare(info->clk);
> >  	media_entity_cleanup(&info->sd.entity);
> > -	ov7670_s_power(sd, 0);
> > +	ov7670_power_off(sd);
> >  	return 0;
> >  }
> >  
> 
> Could you consider instead switching to runtime PM? A few drivers such as
> the ov2685 driver does that already.

Yes, I'll take a look. Thanks for the suggestion. I didn't know such
thing exists, so it may take some time for me to grasp it though.

Take care,
Lubo

>

Patch

diff --git a/drivers/media/i2c/ov7670.c b/drivers/media/i2c/ov7670.c
index ead0c360df33..cbaab60aaaac 100644
--- a/drivers/media/i2c/ov7670.c
+++ b/drivers/media/i2c/ov7670.c
@@ -242,6 +242,7 @@  struct ov7670_info {
 	struct ov7670_format_struct *fmt;  /* Current format */
 	struct ov7670_win_size *wsize;
 	struct clk *clk;
+	int on;
 	struct gpio_desc *resetb_gpio;
 	struct gpio_desc *pwdn_gpio;
 	unsigned int mbus_config;	/* Media bus configuration flags */
@@ -1615,19 +1616,54 @@  static int ov7670_s_register(struct v4l2_subdev *sd, const struct v4l2_dbg_regis
 }
 #endif
 
-static int ov7670_s_power(struct v4l2_subdev *sd, int on)
+static void ov7670_power_on(struct v4l2_subdev *sd)
 {
 	struct ov7670_info *info = to_state(sd);
 
+	if (info->on)
+		return;
+
 	if (info->pwdn_gpio)
-		gpiod_set_value(info->pwdn_gpio, !on);
-	if (on && info->resetb_gpio) {
+		gpiod_set_value(info->pwdn_gpio, 0);
+	if (info->resetb_gpio) {
 		gpiod_set_value(info->resetb_gpio, 1);
 		usleep_range(500, 1000);
 		gpiod_set_value(info->resetb_gpio, 0);
 		usleep_range(3000, 5000);
 	}
 
+	info->on = true;
+}
+
+static void ov7670_power_off(struct v4l2_subdev *sd)
+{
+	struct ov7670_info *info = to_state(sd);
+
+	if (!info->on)
+		return;
+
+	if (info->pwdn_gpio)
+		gpiod_set_value(info->pwdn_gpio, 1);
+
+	info->on = false;
+}
+
+static int ov7670_s_power(struct v4l2_subdev *sd, int on)
+{
+	struct ov7670_info *info = to_state(sd);
+
+	if (info->on == on)
+		return 0;
+
+	if (on) {
+		ov7670_power_on (sd);
+		ov7670_apply_fmt(sd);
+		ov7675_apply_framerate(sd);
+		v4l2_ctrl_handler_setup(&info->hdl);
+	} else {
+		ov7670_power_off (sd);
+	}
+
 	return 0;
 }
 
@@ -1660,6 +1696,7 @@  static int ov7670_open(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh)
 static const struct v4l2_subdev_core_ops ov7670_core_ops = {
 	.reset = ov7670_reset,
 	.init = ov7670_init,
+	.s_power = ov7670_s_power,
 #ifdef CONFIG_VIDEO_ADV_DEBUG
 	.g_register = ov7670_g_register,
 	.s_register = ov7670_s_register,
@@ -1825,6 +1862,7 @@  static int ov7670_probe(struct i2c_client *client,
 		else
 			return ret;
 	}
+
 	if (info->clk) {
 		ret = clk_prepare_enable(info->clk);
 		if (ret)
@@ -1841,7 +1879,7 @@  static int ov7670_probe(struct i2c_client *client,
 	if (ret)
 		goto clk_disable;
 
-	ov7670_s_power(sd, 1);
+	ov7670_power_on(sd);
 
 	/* Make sure it's an ov7670 */
 	ret = ov7670_detect(sd);
@@ -1929,7 +1967,7 @@  static int ov7670_probe(struct i2c_client *client,
 hdl_free:
 	v4l2_ctrl_handler_free(&info->hdl);
 power_off:
-	ov7670_s_power(sd, 0);
+	ov7670_power_off(sd);
 clk_disable:
 	clk_disable_unprepare(info->clk);
 	return ret;
@@ -1945,7 +1983,7 @@  static int ov7670_remove(struct i2c_client *client)
 	v4l2_ctrl_handler_free(&info->hdl);
 	clk_disable_unprepare(info->clk);
 	media_entity_cleanup(&info->sd.entity);
-	ov7670_s_power(sd, 0);
+	ov7670_power_off(sd);
 	return 0;
 }
 

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