Re: [PATCH v3 2/4] media: i2c: ov5645: Switch to assigned-clock-rates

From: Laurent Pinchart
Date: Fri Mar 13 2020 - 17:16:53 EST


Hi Prabakhar,

Thank you for the patch.

On Fri, Mar 13, 2020 at 09:12:32PM +0000, Lad Prabhakar wrote:
> This patch switches to assigned-clock-rates for specifying the clock rate.
> The clk-conf.c internally handles setting the clock rate when
> assigned-clock-rates is passed.
>
> The driver now sets the clock frequency only if the deprecated property
> clock-frequency is defined instead assigned-clock-rates, this is to avoid
> breakage with existing DT binaries.
>
> Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@xxxxxxxxxxxxxx>
> ---
> drivers/media/i2c/ov5645.c | 21 +++++++++++----------
> 1 file changed, 11 insertions(+), 10 deletions(-)
>
> diff --git a/drivers/media/i2c/ov5645.c b/drivers/media/i2c/ov5645.c
> index a6c17d1..4fbabf3 100644
> --- a/drivers/media/i2c/ov5645.c
> +++ b/drivers/media/i2c/ov5645.c
> @@ -1055,6 +1055,7 @@ static int ov5645_probe(struct i2c_client *client)
> struct device_node *endpoint;
> struct ov5645 *ov5645;
> u8 chip_id_high, chip_id_low;
> + bool set_clk = false;

This isn't used.

> unsigned int i;
> u32 xclk_freq;
> int ret;
> @@ -1094,12 +1095,18 @@ static int ov5645_probe(struct i2c_client *client)
> return PTR_ERR(ov5645->xclk);
> }
>
> - ret = of_property_read_u32(dev->of_node, "clock-frequency", &xclk_freq);
> - if (ret) {
> - dev_err(dev, "could not get xclk frequency\n");
> - return ret;
> + /* check if deprecated property clock-frequency is defined */
> + ret = of_property_read_u32(dev->of_node, "clock-frequency",
> + &xclk_freq);
> + if (!ret) {
> + ret = clk_set_rate(ov5645->xclk, xclk_freq);
> + if (ret) {
> + dev_err(dev, "could not set xclk frequency\n");
> + return ret;
> + }
> }
>
> + xclk_freq = clk_get_rate(ov5645->xclk);

I would move this line below the comment.

Reviewed-by: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx>

> /* external clock must be 24MHz, allow 1% tolerance */
> if (xclk_freq < 23760000 || xclk_freq > 24240000) {
> dev_err(dev, "external clock frequency %u is not supported\n",
> @@ -1107,12 +1114,6 @@ static int ov5645_probe(struct i2c_client *client)
> return -EINVAL;
> }
>
> - ret = clk_set_rate(ov5645->xclk, xclk_freq);
> - if (ret) {
> - dev_err(dev, "could not set xclk frequency\n");
> - return ret;
> - }
> -
> for (i = 0; i < OV5645_NUM_SUPPLIES; i++)
> ov5645->supplies[i].supply = ov5645_supply_name[i];
>

--
Regards,

Laurent Pinchart