Hi Jacopo,
On Tue, Mar 29, 2022 at 11:01:31AM +0200, Jacopo Mondi wrote:
> Implement the power up and power down routines and install them as
> runtime_pm handler for runtime_suspend and runtime_resume operations.
>
> Rework the runtime_pm enablement and the chip power handling during
> probe, as calling pm_runtime_idle() in a driver that registers no
> idle callback is a nop.
>
> Signed-off-by: Jacopo Mondi <jacopo@xxxxxxxxxx>
> ---
> drivers/media/i2c/ov5670.c | 58 ++++++++++++++++++++++++++++++++++----
> 1 file changed, 52 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/media/i2c/ov5670.c b/drivers/media/i2c/ov5670.c
> index 9e69b4008917..b63b07d8ca2f 100644
> --- a/drivers/media/i2c/ov5670.c
> +++ b/drivers/media/i2c/ov5670.c
> @@ -4,6 +4,7 @@
> #include <linux/acpi.h>
> #include <linux/clk.h>
> #include <linux/gpio/consumer.h>
> +#include <linux/delay.h>
> #include <linux/i2c.h>
> #include <linux/mod_devicetable.h>
> #include <linux/module.h>
> @@ -2424,6 +2425,39 @@ static int ov5670_set_stream(struct v4l2_subdev *sd, int enable)
> return ret;
> }
>
> +static int __maybe_unused ov5670_runtime_resume(struct device *dev)
> +{
> + struct i2c_client *client = to_i2c_client(dev);
> + struct v4l2_subdev *sd = i2c_get_clientdata(client);
> + struct ov5670 *ov5670 = to_ov5670(sd);
> + int ret;
> +
> + ret = regulator_bulk_enable(OV5670_NUM_SUPPLIES, ov5670->supplies);
> + if (ret)
> + return ret;
> +
> + gpiod_set_value_cansleep(ov5670->pwdn_gpio, 0);
> + gpiod_set_value_cansleep(ov5670->reset_gpio, 0);
> +
> + /* 8192 * 2 clock pulses before the first SCCB transaction. */
> + usleep_range(1000, 1500);
> +
> + return 0;
> +}
> +
> +static int __maybe_unused ov5670_runtime_suspend(struct device *dev)
> +{
> + struct i2c_client *client = to_i2c_client(dev);
> + struct v4l2_subdev *sd = i2c_get_clientdata(client);
> + struct ov5670 *ov5670 = to_ov5670(sd);
> +
> + gpiod_set_value_cansleep(ov5670->reset_gpio, 1);
> + gpiod_set_value_cansleep(ov5670->pwdn_gpio, 1);
> + regulator_bulk_disable(OV5670_NUM_SUPPLIES, ov5670->supplies);
> +
> + return 0;
> +}
> +
> static int __maybe_unused ov5670_suspend(struct device *dev)
> {
> struct v4l2_subdev *sd = dev_get_drvdata(dev);
> @@ -2564,14 +2598,25 @@ static int ov5670_probe(struct i2c_client *client)
> goto error_print;
> }
>
> + pm_runtime_enable(&client->dev);
> +
> full_power = acpi_dev_state_d0(&client->dev);
> if (full_power) {
> + ret = pm_runtime_resume_and_get(&client->dev);
This will power the device on, but only on OF systems.
Could you instead power the device on on OF systems explicitly? That's what
other drivers do, too. The changes would be probably more simple to
implement, too.
> + if (ret) {
> + err_msg = "Failed to power on";
> + goto error_print;
> + }
> +
> /* Check module identity */
> ret = ov5670_identify_module(ov5670);
> if (ret) {
> err_msg = "ov5670_identify_module() error";
> - goto error_print;
> + goto error_power_off;
> }
> +
> + /* Set the device's state to active if it's in D0 state. */
> + pm_runtime_set_active(&client->dev);
> }
>
> mutex_init(&ov5670->mutex);
> @@ -2608,11 +2653,7 @@ static int ov5670_probe(struct i2c_client *client)
>
> ov5670->streaming = false;
>
> - /* Set the device's state to active if it's in D0 state. */
> - if (full_power)
> - pm_runtime_set_active(&client->dev);
> - pm_runtime_enable(&client->dev);
> - pm_runtime_idle(&client->dev);
> + pm_runtime_suspend(&client->dev);
>
> return 0;
>
> @@ -2625,6 +2666,9 @@ static int ov5670_probe(struct i2c_client *client)
> error_mutex_destroy:
> mutex_destroy(&ov5670->mutex);
>
> +error_power_off:
> + pm_runtime_put(&client->dev);
> +
> error_print:
> dev_err(&client->dev, "%s: %s %d\n", __func__, err_msg, ret);
>
> @@ -2641,6 +2685,7 @@ static int ov5670_remove(struct i2c_client *client)
> v4l2_ctrl_handler_free(sd->ctrl_handler);
> mutex_destroy(&ov5670->mutex);
>
> + pm_runtime_put(&client->dev);
> pm_runtime_disable(&client->dev);
>
> return 0;
> @@ -2648,6 +2693,7 @@ static int ov5670_remove(struct i2c_client *client)
>
> static const struct dev_pm_ops ov5670_pm_ops = {
> SET_SYSTEM_SLEEP_PM_OPS(ov5670_suspend, ov5670_resume)
> + SET_RUNTIME_PM_OPS(ov5670_runtime_suspend, ov5670_runtime_resume, NULL)
> };
>
> #ifdef CONFIG_ACPI
--
Regards,
Sakari Ailus
