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.
The suspend callback is called by rpm_idle() in the absence of the
idle callback.
>
> 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);
Please see how e.g. the CCS driver does this (no need for autosuspend
though). E.g. don't use runtime PM to power the sensor on in probe, or off
in remove.
> + 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
--
Kind regards,
Sakari Ailus
