[PATCH v4 6/9] media: i2c: ov5645: Use runtime PM

From: Prabhakar
Date: Mon Oct 31 2022 - 19:22:45 EST


From: Lad Prabhakar <prabhakar.mahadev-lad.rj@xxxxxxxxxxxxxx>

Switch to using runtime PM for power management.

Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@xxxxxxxxxxxxxx>
Reviewed-by: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx>
---
v3->v4
* Fixed comments pointed by Sakari

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/ov5645.c | 133 +++++++++++++++++++------------------
1 file changed, 68 insertions(+), 65 deletions(-)

diff --git a/drivers/media/i2c/ov5645.c b/drivers/media/i2c/ov5645.c
index 47451238ca05..2e6135d0a31a 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) {
@@ -1233,20 +1217,30 @@ static int ov5645_probe(struct i2c_client *client)
goto power_down;
}

- ov5645_s_power(&ov5645->sd, false);
+ pm_runtime_set_active(dev);
+ pm_runtime_get_noresume(dev);
+ pm_runtime_enable(dev);

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,
--
2.25.1