On Tue, Mar 10, 2020 at 10:47 AM Robert Foss <robert.foss@xxxxxxxxxx> wrote:
> +static int __ov8856_power_on(struct ov8856 *ov8856)
> +{
> + struct i2c_client *client = v4l2_get_subdevdata(&ov8856->sd);
> + int ret;
> +
> + ret = clk_prepare_enable(ov8856->xvclk);
> + if (ret < 0) {
> + dev_err(&client->dev, "failed to enable xvclk\n");
> + return ret;
> + }
> +
> + gpiod_set_value_cansleep(ov8856->n_shutdn_gpio, GPIOD_OUT_LOW);
> +
> + ret = regulator_bulk_enable(OV8856_NUM_SUPPLIES, ov8856->supplies);
> + if (ret < 0) {
> + dev_err(&client->dev, "failed to enable regulators\n");
> + goto disable_clk;
> + }
> +
> + gpiod_set_value_cansleep(ov8856->n_shutdn_gpio, GPIOD_OUT_HIGH);
To power it up you probably only need:
gpiod_set_value_cansleep(ov8856->n_shutdn_gpio, 0);
And use reset-gpios as active low in your device tree. Assuming the
reset-gpios is active low like other OmniVision sensors.
> +
> + usleep_range(1500, 1800);
> +
> + return 0;
> +
> +disable_clk:
> + clk_disable_unprepare(ov8856->xvclk);
> +
> + return ret;
> +}
> +
> +static void __ov8856_power_off(struct ov8856 *ov8856)
> +{
> + gpiod_set_value_cansleep(ov8856->n_shutdn_gpio, GPIOD_OUT_LOW);
> + regulator_bulk_disable(OV8856_NUM_SUPPLIES, ov8856->supplies);
> + clk_disable_unprepare(ov8856->xvclk);
> +}
> +
> +
Unneede extra blank line.
> v4l2_i2c_subdev_init(&ov8856->sd, client, &ov8856_subdev_ops);
> + ov8856->xvclk = devm_clk_get(&client->dev, "xvclk");
> + if (IS_ERR(ov8856->xvclk)) {
> + dev_err(&client->dev, "failed to get xvclk\n");
> + return -EINVAL;
You should better return the real error insteald
PTR_ERR(ov8856->xvclk). This way defer probe could work.
> + }
> +
> + ret = clk_set_rate(ov8856->xvclk, OV8856_XVCLK_24);
> + if (ret < 0) {
> + dev_err(&client->dev, "failed to set xvclk rate (24MHz)\n");
> + return ret;
> + }
> +
> + ov8856->n_shutdn_gpio = devm_gpiod_get(&client->dev, "reset",
> + GPIOD_OUT_LOW);
> + if (IS_ERR(ov8856->n_shutdn_gpio)) {
> + dev_err(&client->dev, "failed to get reset-gpios\n");
> + return -EINVAL;
Please return the real error.
