Re: [PATCH v3 4/4] media: i2c: ov2659: Use clk_{prepare_enable,disable_unprepare}() to set xvclk on/off

From: dillon min
Date: Tue Apr 20 2021 - 02:46:28 EST


Hi All,

Just a gentle ping, hope some expert could take a look, thanks.

Best regards.
Dillon

On Thu, Apr 15, 2021 at 12:06 PM <dillon.minfei@xxxxxxxxx> wrote:
>
> From: dillon min <dillon.minfei@xxxxxxxxx>
>
> On some platform(imx6q), xvclk might not switch on in advance,
> also for power save purpose, xvclk should not be always on.
> so, add clk_prepare_enable(), clk_disable_unprepare() in driver
> side to set xvclk on/off at proper stage.
>
> Add following changes:
> - add 'struct clk *clk;' in 'struct ov2659 {}'
> - enable xvclk in ov2659_power_on()
> - disable xvclk in ov2659_power_off()
>
> Signed-off-by: dillon min <dillon.minfei@xxxxxxxxx>
> ---
> v3: optimize commit message
>
> drivers/media/i2c/ov2659.c | 24 ++++++++++++++++++------
> 1 file changed, 18 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/media/i2c/ov2659.c b/drivers/media/i2c/ov2659.c
> index 42f64175a6df..fb78a1cedc03 100644
> --- a/drivers/media/i2c/ov2659.c
> +++ b/drivers/media/i2c/ov2659.c
> @@ -204,6 +204,7 @@ struct ov2659 {
> struct i2c_client *client;
> struct v4l2_ctrl_handler ctrls;
> struct v4l2_ctrl *link_frequency;
> + struct clk *clk;
> const struct ov2659_framesize *frame_size;
> struct sensor_register *format_ctrl_regs;
> struct ov2659_pll_ctrl pll;
> @@ -1270,6 +1271,8 @@ static int ov2659_power_off(struct device *dev)
>
> gpiod_set_value(ov2659->pwdn_gpio, 1);
>
> + clk_disable_unprepare(ov2659->clk);
> +
> return 0;
> }
>
> @@ -1278,9 +1281,17 @@ static int ov2659_power_on(struct device *dev)
> struct i2c_client *client = to_i2c_client(dev);
> struct v4l2_subdev *sd = i2c_get_clientdata(client);
> struct ov2659 *ov2659 = to_ov2659(sd);
> + int ret;
>
> dev_dbg(&client->dev, "%s:\n", __func__);
>
> + ret = clk_prepare_enable(ov2659->clk);
> + if (ret) {
> + dev_err(&client->dev, "%s: failed to enable clock\n",
> + __func__);
> + return ret;
> + }
> +
> gpiod_set_value(ov2659->pwdn_gpio, 0);
>
> if (ov2659->resetb_gpio) {
> @@ -1425,7 +1436,6 @@ static int ov2659_probe(struct i2c_client *client)
> const struct ov2659_platform_data *pdata = ov2659_get_pdata(client);
> struct v4l2_subdev *sd;
> struct ov2659 *ov2659;
> - struct clk *clk;
> int ret;
>
> if (!pdata) {
> @@ -1440,11 +1450,11 @@ static int ov2659_probe(struct i2c_client *client)
> ov2659->pdata = pdata;
> ov2659->client = client;
>
> - clk = devm_clk_get(&client->dev, "xvclk");
> - if (IS_ERR(clk))
> - return PTR_ERR(clk);
> + ov2659->clk = devm_clk_get(&client->dev, "xvclk");
> + if (IS_ERR(ov2659->clk))
> + return PTR_ERR(ov2659->clk);
>
> - ov2659->xvclk_frequency = clk_get_rate(clk);
> + ov2659->xvclk_frequency = clk_get_rate(ov2659->clk);
> if (ov2659->xvclk_frequency < 6000000 ||
> ov2659->xvclk_frequency > 27000000)
> return -EINVAL;
> @@ -1506,7 +1516,9 @@ static int ov2659_probe(struct i2c_client *client)
> ov2659->frame_size = &ov2659_framesizes[2];
> ov2659->format_ctrl_regs = ov2659_formats[0].format_ctrl_regs;
>
> - ov2659_power_on(&client->dev);
> + ret = ov2659_power_on(&client->dev);
> + if (ret < 0)
> + goto error;
>
> ret = ov2659_detect(sd);
> if (ret < 0)
> --
> 2.7.4
>