linux-kernel - Re: [PATCH v1 55/55] media: i2c: ov2680: Use the v4l2 helper for obtaining the clock

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Message-ID: <20250619220002.GT22102@pendragon.ideasonboard.com>
Date: Fri, 20 Jun 2025 01:00:02 +0300
From: Laurent Pinchart <laurent.pinchart@...asonboard.com>
To: Mehdi Djait <mehdi.djait@...ux.intel.com>
Cc: sakari.ailus@...ux.intel.com, akinobu.mita@...il.com,
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Subject: Re: [PATCH v1 55/55] media: i2c: ov2680: Use the v4l2 helper for
 obtaining the clock

Hi Mehdi,

Thank you for the patch.

On Thu, Jun 19, 2025 at 08:11:24PM +0200, Mehdi Djait wrote:
> Use the new v4l2 helper devm_v4l2_sensor_clk_get() that works on both
> DT- and ACPI-based platforms to retrieve a reference to the clock
> producer from firmware.
> 
> Signed-off-by: Mehdi Djait <mehdi.djait@...ux.intel.com>
> 
> diff --git a/drivers/media/i2c/ov2680.c b/drivers/media/i2c/ov2680.c
> index 7237fb27ecd0..c974169c92f8 100644
> --- a/drivers/media/i2c/ov2680.c
> +++ b/drivers/media/i2c/ov2680.c
> @@ -1079,7 +1079,6 @@ static int ov2680_parse_dt(struct ov2680_dev *sensor)
>  	struct device *dev = sensor->dev;
>  	struct fwnode_handle *ep_fwnode;
>  	struct gpio_desc *gpio;
> -	unsigned int rate = 0;
>  	int i, ret;
>  
>  	/*
> @@ -1114,13 +1113,6 @@ static int ov2680_parse_dt(struct ov2680_dev *sensor)
>  
>  	sensor->pwdn_gpio = gpio;
>  
> -	sensor->xvclk = devm_clk_get_optional(dev, "xvclk");
> -	if (IS_ERR(sensor->xvclk)) {
> -		ret = dev_err_probe(dev, PTR_ERR(sensor->xvclk),
> -				    "xvclk clock missing or invalid\n");
> -		goto out_free_bus_cfg;
> -	}
> -
>  	/*
>  	 * We could have either a 24MHz or 19.2MHz clock rate from either DT or
>  	 * ACPI... but we also need to support the weird IPU3 case which will
> @@ -1130,22 +1122,15 @@ static int ov2680_parse_dt(struct ov2680_dev *sensor)
>  	 * uses devicetree then the configured rate should already be set, so
>  	 * we can just read it.
>  	 */

Shouldn't you drop the comment, as in 41/55 ?

Apart from that, the patch looks good to me.

> -	ret = fwnode_property_read_u32(dev_fwnode(dev), "clock-frequency",
> -				       &rate);
> -	if (ret && !sensor->xvclk) {
> -		dev_err_probe(dev, ret, "invalid clock config\n");
> +
> +	sensor->xvclk = devm_v4l2_sensor_clk_get(dev, "xvclk");
> +	if (IS_ERR(sensor->xvclk)) {
> +		ret = dev_err_probe(dev, PTR_ERR(sensor->xvclk),
> +				    "xvclk clock missing or invalid\n");
>  		goto out_free_bus_cfg;
>  	}
>  
> -	if (!ret && sensor->xvclk) {
> -		ret = clk_set_rate(sensor->xvclk, rate);
> -		if (ret) {
> -			dev_err_probe(dev, ret, "failed to set clock rate\n");
> -			goto out_free_bus_cfg;
> -		}
> -	}
> -
> -	sensor->xvclk_freq = rate ?: clk_get_rate(sensor->xvclk);
> +	sensor->xvclk_freq = clk_get_rate(sensor->xvclk);
>  
>  	for (i = 0; i < ARRAY_SIZE(ov2680_xvclk_freqs); i++) {
>  		if (sensor->xvclk_freq == ov2680_xvclk_freqs[i])

-- 
Regards,

Laurent Pinchart