Hi Jacopo,
Thank you for the patch.
On Thu, Mar 10, 2022 at 02:08:28PM +0100, 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 | 59 ++++++++++++++++++++++++++++++++++----
> 1 file changed, 53 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/media/i2c/ov5670.c b/drivers/media/i2c/ov5670.c
> index ca5191d043ce..c9f69ffef210 100644
> --- a/drivers/media/i2c/ov5670.c
> +++ b/drivers/media/i2c/ov5670.c
> @@ -2,6 +2,8 @@
> // Copyright (c) 2017 Intel Corporation.
>
> #include <linux/acpi.h>
> +#include <linux/delay.h>
> +#include <linux/gpio/consumer.h>
Isn't this header needed in the previous patch ?
> #include <linux/i2c.h>
> #include <linux/mod_devicetable.h>
> #include <linux/module.h>
> @@ -2422,6 +2424,39 @@ static int ov5670_set_stream(struct v4l2_subdev *sd, int enable)
> return ret;
> }
>
> +static int __maybe_unused ov5670_power_on(struct device *dev)
I'd name this ov5670_runtime_resume(), and the following function
ov5670_runtime_suspend().
> +{
> + struct i2c_client *client = to_i2c_client(dev);
> + struct v4l2_subdev *sd = i2c_get_clientdata(client);
> + struct ov5670 *ov5670 = to_ov5670(sd);
> + int ret = 0;
No need to initialize 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_power_off(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);
> @@ -2549,14 +2584,25 @@ static int ov5670_probe(struct i2c_client *client)
> goto error_print;
> }
>
> + pm_runtime_enable(&client->dev);
> +
> full_power = acpi_dev_state_d0(&client->dev);
That's peculiar. Sakari, is this needed, or is there a way to rely on
runtime PM only ? Or on another API that would abstract the differences
between ACPI and OF ?
> if (full_power) {
> + ret = pm_runtime_resume_and_get(&client->dev);
> + 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);
> @@ -2593,11 +2639,7 @@ 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;
>
> @@ -2610,6 +2652,9 @@ 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);
>
> @@ -2626,6 +2671,7 @@ 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;
> @@ -2633,6 +2679,7 @@ 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_power_off, ov5670_power_on, NULL)
> };
>
> #ifdef CONFIG_ACPI
--
Regards,
Laurent Pinchart
