[v3,6/9] media: i2c: ov5645: Use runtime PM

Message ID 20221026130658.45601-7-prabhakar.mahadev-lad.rj@bp.renesas.com
State New
Headers
Series media: i2c: ov5645 driver enhancements |

Commit Message

Lad, Prabhakar Oct. 26, 2022, 1:06 p.m. UTC
  From: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>

Switch to using runtime PM for power management.

Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
---
v2->v3
* Jumped to err_pm_runtime label in case of sd register failure
* Now calling pm_runtime_mark_last_busy() before pm_runtime_put_autosuspend()
  call
* Now calling pm_runtime_put_sync() in case s_stream(1) fails
* In s_stream(0) no calling pm_runtime_mark_last_busy() and
  pm_runtime_put_autosuspend()
* Included RB tag from Laurent.

v1->v2
* Moved pm_runtime_*_autosuspend() calls after registering the subdev.
---
 drivers/media/i2c/Kconfig  |   2 +-
 drivers/media/i2c/ov5645.c | 141 +++++++++++++++++++------------------
 2 files changed, 73 insertions(+), 70 deletions(-)
  

Comments

Sakari Ailus Oct. 27, 2022, 9:22 a.m. UTC | #1
Hi Prabhakar,

Thanks for the update.

On Wed, Oct 26, 2022 at 02:06:55PM +0100, Prabhakar wrote:
> From: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
> 
> Switch to using runtime PM for power management.
> 
> Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
> ---
> v2->v3
> * Jumped to err_pm_runtime label in case of sd register failure
> * Now calling pm_runtime_mark_last_busy() before pm_runtime_put_autosuspend()
>   call
> * Now calling pm_runtime_put_sync() in case s_stream(1) fails
> * In s_stream(0) no calling pm_runtime_mark_last_busy() and
>   pm_runtime_put_autosuspend()
> * Included RB tag from Laurent.
> 
> v1->v2
> * Moved pm_runtime_*_autosuspend() calls after registering the subdev.
> ---
>  drivers/media/i2c/Kconfig  |   2 +-
>  drivers/media/i2c/ov5645.c | 141 +++++++++++++++++++------------------
>  2 files changed, 73 insertions(+), 70 deletions(-)
> 
> diff --git a/drivers/media/i2c/Kconfig b/drivers/media/i2c/Kconfig
> index 7806d4b81716..c0edd1017fe8 100644
> --- a/drivers/media/i2c/Kconfig
> +++ b/drivers/media/i2c/Kconfig
> @@ -459,7 +459,7 @@ config VIDEO_OV5640
>  config VIDEO_OV5645
>  	tristate "OmniVision OV5645 sensor support"
>  	depends on OF
> -	depends on I2C && VIDEO_DEV
> +	depends on I2C && PM && VIDEO_DEV

I think you can drop the PM dependency --- the driver will work fine
without CONFIG_PM.

Although one could question why do we have CONFIG_PM. Some systems won't
boot without it and who would want to consume more power than necessary?

Could this be removed altogether? Or perhaps we could add CONFIG_PM
dependency to V4L2 and DVB? :-)

Certainly out of scope of this set though.
  
Lad, Prabhakar Oct. 27, 2022, 9:48 a.m. UTC | #2
Hi Sakari,

On Thu, Oct 27, 2022 at 10:22 AM Sakari Ailus
<sakari.ailus@linux.intel.com> wrote:
>
> Hi Prabhakar,
>
> Thanks for the update.
>
> On Wed, Oct 26, 2022 at 02:06:55PM +0100, Prabhakar wrote:
> > From: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
> >
> > Switch to using runtime PM for power management.
> >
> > Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
> > Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
> > ---
> > v2->v3
> > * Jumped to err_pm_runtime label in case of sd register failure
> > * Now calling pm_runtime_mark_last_busy() before pm_runtime_put_autosuspend()
> >   call
> > * Now calling pm_runtime_put_sync() in case s_stream(1) fails
> > * In s_stream(0) no calling pm_runtime_mark_last_busy() and
> >   pm_runtime_put_autosuspend()
> > * Included RB tag from Laurent.
> >
> > v1->v2
> > * Moved pm_runtime_*_autosuspend() calls after registering the subdev.
> > ---
> >  drivers/media/i2c/Kconfig  |   2 +-
> >  drivers/media/i2c/ov5645.c | 141 +++++++++++++++++++------------------
> >  2 files changed, 73 insertions(+), 70 deletions(-)
> >
> > diff --git a/drivers/media/i2c/Kconfig b/drivers/media/i2c/Kconfig
> > index 7806d4b81716..c0edd1017fe8 100644
> > --- a/drivers/media/i2c/Kconfig
> > +++ b/drivers/media/i2c/Kconfig
> > @@ -459,7 +459,7 @@ config VIDEO_OV5640
> >  config VIDEO_OV5645
> >       tristate "OmniVision OV5645 sensor support"
> >       depends on OF
> > -     depends on I2C && VIDEO_DEV
> > +     depends on I2C && PM && VIDEO_DEV
>
> I think you can drop the PM dependency --- the driver will work fine
> without CONFIG_PM.
>
Agreed, I'll send a new version dropping this and fixing the comments
on patch #5 and patch #8.

> Although one could question why do we have CONFIG_PM. Some systems won't
> boot without it and who would want to consume more power than necessary?
>
> Could this be removed altogether? Or perhaps we could add CONFIG_PM
> dependency to V4L2 and DVB? :-)
>
Or rather this option should be selected by the platform itself rather
than subsystem?

Cheers,
Prabhakar
  

Patch

diff --git a/drivers/media/i2c/Kconfig b/drivers/media/i2c/Kconfig
index 7806d4b81716..c0edd1017fe8 100644
--- a/drivers/media/i2c/Kconfig
+++ b/drivers/media/i2c/Kconfig
@@ -459,7 +459,7 @@  config VIDEO_OV5640
 config VIDEO_OV5645
 	tristate "OmniVision OV5645 sensor support"
 	depends on OF
-	depends on I2C && VIDEO_DEV
+	depends on I2C && PM && VIDEO_DEV
 	select MEDIA_CONTROLLER
 	select VIDEO_V4L2_SUBDEV_API
 	select V4L2_FWNODE
diff --git a/drivers/media/i2c/ov5645.c b/drivers/media/i2c/ov5645.c
index 47451238ca05..4438dc91b82a 100644
--- a/drivers/media/i2c/ov5645.c
+++ b/drivers/media/i2c/ov5645.c
@@ -27,6 +27,7 @@ 
 #include <linux/module.h>
 #include <linux/of.h>
 #include <linux/of_graph.h>
+#include <linux/pm_runtime.h>
 #include <linux/regulator/consumer.h>
 #include <linux/slab.h>
 #include <linux/types.h>
@@ -108,7 +109,6 @@  struct ov5645 {
 	u8 timing_tc_reg21;
 
 	struct mutex power_lock; /* lock to protect power state */
-	int power_count;
 
 	struct gpio_desc *enable_gpio;
 	struct gpio_desc *rst_gpio;
@@ -635,8 +635,24 @@  static int ov5645_set_register_array(struct ov5645 *ov5645,
 	return 0;
 }
 
-static int ov5645_set_power_on(struct ov5645 *ov5645)
+static int ov5645_set_power_off(struct device *dev)
 {
+	struct v4l2_subdev *sd = dev_get_drvdata(dev);
+	struct ov5645 *ov5645 = to_ov5645(sd);
+
+	ov5645_write_reg(ov5645, OV5645_IO_MIPI_CTRL00, 0x58);
+	gpiod_set_value_cansleep(ov5645->rst_gpio, 1);
+	gpiod_set_value_cansleep(ov5645->enable_gpio, 0);
+	clk_disable_unprepare(ov5645->xclk);
+	regulator_bulk_disable(OV5645_NUM_SUPPLIES, ov5645->supplies);
+
+	return 0;
+}
+
+static int ov5645_set_power_on(struct device *dev)
+{
+	struct v4l2_subdev *sd = dev_get_drvdata(dev);
+	struct ov5645 *ov5645 = to_ov5645(sd);
 	int ret;
 
 	ret = regulator_bulk_enable(OV5645_NUM_SUPPLIES, ov5645->supplies);
@@ -658,57 +674,19 @@  static int ov5645_set_power_on(struct ov5645 *ov5645)
 
 	msleep(20);
 
-	return 0;
-}
-
-static void ov5645_set_power_off(struct ov5645 *ov5645)
-{
-	gpiod_set_value_cansleep(ov5645->rst_gpio, 1);
-	gpiod_set_value_cansleep(ov5645->enable_gpio, 0);
-	clk_disable_unprepare(ov5645->xclk);
-	regulator_bulk_disable(OV5645_NUM_SUPPLIES, ov5645->supplies);
-}
-
-static int ov5645_s_power(struct v4l2_subdev *sd, int on)
-{
-	struct ov5645 *ov5645 = to_ov5645(sd);
-	int ret = 0;
-
-	mutex_lock(&ov5645->power_lock);
-
-	/* If the power count is modified from 0 to != 0 or from != 0 to 0,
-	 * update the power state.
-	 */
-	if (ov5645->power_count == !on) {
-		if (on) {
-			ret = ov5645_set_power_on(ov5645);
-			if (ret < 0)
-				goto exit;
-
-			ret = ov5645_set_register_array(ov5645,
-					ov5645_global_init_setting,
+	ret = ov5645_set_register_array(ov5645, ov5645_global_init_setting,
 					ARRAY_SIZE(ov5645_global_init_setting));
-			if (ret < 0) {
-				dev_err(ov5645->dev,
-					"could not set init registers\n");
-				ov5645_set_power_off(ov5645);
-				goto exit;
-			}
-
-			usleep_range(500, 1000);
-		} else {
-			ov5645_write_reg(ov5645, OV5645_IO_MIPI_CTRL00, 0x58);
-			ov5645_set_power_off(ov5645);
-		}
+	if (ret < 0) {
+		dev_err(ov5645->dev, "could not set init registers\n");
+		goto exit;
 	}
 
-	/* Update the power count. */
-	ov5645->power_count += on ? 1 : -1;
-	WARN_ON(ov5645->power_count < 0);
+	usleep_range(500, 1000);
 
-exit:
-	mutex_unlock(&ov5645->power_lock);
+	return 0;
 
+exit:
+	ov5645_set_power_off(dev);
 	return ret;
 }
 
@@ -795,7 +773,7 @@  static int ov5645_s_ctrl(struct v4l2_ctrl *ctrl)
 	int ret;
 
 	mutex_lock(&ov5645->power_lock);
-	if (!ov5645->power_count) {
+	if (!pm_runtime_get_if_in_use(ov5645->dev)) {
 		mutex_unlock(&ov5645->power_lock);
 		return 0;
 	}
@@ -827,6 +805,8 @@  static int ov5645_s_ctrl(struct v4l2_ctrl *ctrl)
 		break;
 	}
 
+	pm_runtime_mark_last_busy(ov5645->dev);
+	pm_runtime_put_autosuspend(ov5645->dev);
 	mutex_unlock(&ov5645->power_lock);
 
 	return ret;
@@ -991,6 +971,10 @@  static int ov5645_s_stream(struct v4l2_subdev *subdev, int enable)
 	int ret;
 
 	if (enable) {
+		ret = pm_runtime_resume_and_get(ov5645->dev);
+		if (ret < 0)
+			return ret;
+
 		ret = ov5645_set_register_array(ov5645,
 					ov5645->current_mode->data,
 					ov5645->current_mode->data_size);
@@ -998,22 +982,22 @@  static int ov5645_s_stream(struct v4l2_subdev *subdev, int enable)
 			dev_err(ov5645->dev, "could not set mode %dx%d\n",
 				ov5645->current_mode->width,
 				ov5645->current_mode->height);
-			return ret;
+			goto err_rpm_put;
 		}
 		ret = v4l2_ctrl_handler_setup(&ov5645->ctrls);
 		if (ret < 0) {
 			dev_err(ov5645->dev, "could not sync v4l2 controls\n");
-			return ret;
+			goto err_rpm_put;
 		}
 
 		ret = ov5645_write_reg(ov5645, OV5645_IO_MIPI_CTRL00, 0x45);
 		if (ret < 0)
-			return ret;
+			goto err_rpm_put;
 
 		ret = ov5645_write_reg(ov5645, OV5645_SYSTEM_CTRL0,
 				       OV5645_SYSTEM_CTRL0_START);
 		if (ret < 0)
-			return ret;
+			goto err_rpm_put;
 	} else {
 		ret = ov5645_write_reg(ov5645, OV5645_IO_MIPI_CTRL00, 0x40);
 		if (ret < 0)
@@ -1023,14 +1007,17 @@  static int ov5645_s_stream(struct v4l2_subdev *subdev, int enable)
 				       OV5645_SYSTEM_CTRL0_STOP);
 		if (ret < 0)
 			return ret;
+
+		pm_runtime_mark_last_busy(ov5645->dev);
+		pm_runtime_put_autosuspend(ov5645->dev);
 	}
 
 	return 0;
-}
 
-static const struct v4l2_subdev_core_ops ov5645_core_ops = {
-	.s_power = ov5645_s_power,
-};
+err_rpm_put:
+	pm_runtime_put_sync(ov5645->dev);
+	return ret;
+}
 
 static const struct v4l2_subdev_video_ops ov5645_video_ops = {
 	.s_stream = ov5645_s_stream,
@@ -1046,7 +1033,6 @@  static const struct v4l2_subdev_pad_ops ov5645_subdev_pad_ops = {
 };
 
 static const struct v4l2_subdev_ops ov5645_subdev_ops = {
-	.core = &ov5645_core_ops,
 	.video = &ov5645_video_ops,
 	.pad = &ov5645_subdev_pad_ops,
 };
@@ -1188,11 +1174,9 @@  static int ov5645_probe(struct i2c_client *client)
 		goto free_ctrl;
 	}
 
-	ret = ov5645_s_power(&ov5645->sd, true);
-	if (ret < 0) {
-		dev_err(dev, "could not power up OV5645\n");
+	ret = ov5645_set_power_on(dev);
+	if (ret)
 		goto free_entity;
-	}
 
 	ret = ov5645_read_reg(ov5645, OV5645_CHIP_ID_HIGH, &chip_id_high);
 	if (ret < 0 || chip_id_high != OV5645_CHIP_ID_HIGH_BYTE) {
@@ -1209,12 +1193,16 @@  static int ov5645_probe(struct i2c_client *client)
 
 	dev_info(dev, "OV5645 detected at address 0x%02x\n", client->addr);
 
+	pm_runtime_set_active(dev);
+	pm_runtime_get_noresume(dev);
+	pm_runtime_enable(dev);
+
 	ret = ov5645_read_reg(ov5645, OV5645_AEC_PK_MANUAL,
 			      &ov5645->aec_pk_manual);
 	if (ret < 0) {
 		dev_err(dev, "could not read AEC/AGC mode\n");
 		ret = -ENODEV;
-		goto power_down;
+		goto err_pm_runtime;
 	}
 
 	ret = ov5645_read_reg(ov5645, OV5645_TIMING_TC_REG20,
@@ -1222,7 +1210,7 @@  static int ov5645_probe(struct i2c_client *client)
 	if (ret < 0) {
 		dev_err(dev, "could not read vflip value\n");
 		ret = -ENODEV;
-		goto power_down;
+		goto err_pm_runtime;
 	}
 
 	ret = ov5645_read_reg(ov5645, OV5645_TIMING_TC_REG21,
@@ -1230,23 +1218,29 @@  static int ov5645_probe(struct i2c_client *client)
 	if (ret < 0) {
 		dev_err(dev, "could not read hflip value\n");
 		ret = -ENODEV;
-		goto power_down;
+		goto err_pm_runtime;
 	}
 
-	ov5645_s_power(&ov5645->sd, false);
-
 	ret = v4l2_async_register_subdev(&ov5645->sd);
 	if (ret < 0) {
 		dev_err(dev, "could not register v4l2 device\n");
-		goto free_entity;
+		goto err_pm_runtime;
 	}
 
+	pm_runtime_set_autosuspend_delay(dev, 1000);
+	pm_runtime_use_autosuspend(dev);
+	pm_runtime_mark_last_busy(dev);
+	pm_runtime_put_autosuspend(dev);
+
 	ov5645_entity_init_cfg(&ov5645->sd, NULL);
 
 	return 0;
 
+err_pm_runtime:
+	pm_runtime_disable(dev);
+	pm_runtime_put_noidle(dev);
 power_down:
-	ov5645_s_power(&ov5645->sd, false);
+	ov5645_set_power_off(dev);
 free_entity:
 	media_entity_cleanup(&ov5645->sd.entity);
 free_ctrl:
@@ -1264,6 +1258,10 @@  static void ov5645_remove(struct i2c_client *client)
 	v4l2_async_unregister_subdev(&ov5645->sd);
 	media_entity_cleanup(&ov5645->sd.entity);
 	v4l2_ctrl_handler_free(&ov5645->ctrls);
+	pm_runtime_disable(ov5645->dev);
+	if (!pm_runtime_status_suspended(ov5645->dev))
+		ov5645_set_power_off(ov5645->dev);
+	pm_runtime_set_suspended(ov5645->dev);
 	mutex_destroy(&ov5645->power_lock);
 }
 
@@ -1279,10 +1277,15 @@  static const struct of_device_id ov5645_of_match[] = {
 };
 MODULE_DEVICE_TABLE(of, ov5645_of_match);
 
+static const struct dev_pm_ops ov5645_pm_ops = {
+	SET_RUNTIME_PM_OPS(ov5645_set_power_off, ov5645_set_power_on, NULL)
+};
+
 static struct i2c_driver ov5645_i2c_driver = {
 	.driver = {
 		.of_match_table = ov5645_of_match,
 		.name  = "ov5645",
+		.pm = &ov5645_pm_ops,
 	},
 	.probe_new = ov5645_probe,
 	.remove = ov5645_remove,