Re: [PATCH v8 3/5] media: stm32-dcmipp: STM32 DCMIPP camera interface driver

[Philipp Zabel <p.zabel@pengutronix.de>]

On Mi, 2023-11-22 at 08:39 +0100, Alain Volmat wrote:
> From: Hugues Fruchet <hugues.fruchet@foss.st.com>
> 
> This V4L2 subdev driver enables Digital Camera Memory Interface
> Pixel Processor(DCMIPP) of STMicroelectronics STM32 SoC series.
> 
> Signed-off-by: Hugues Fruchet <hugues.fruchet@foss.st.com>
> Signed-off-by: Alain Volmat <alain.volmat@foss.st.com>
> ---
[...]
> diff --git a/drivers/media/platform/st/stm32/stm32-dcmipp/dcmipp-core.c b/drivers/media/platform/st/stm32/stm32-dcmipp/dcmipp-core.c
> new file mode 100644
> index 000000000000..28ddb26314c3
> --- /dev/null
> +++ b/drivers/media/platform/st/stm32/stm32-dcmipp/dcmipp-core.c
> @@ -0,0 +1,604 @@
[...]
> +struct dcmipp_device {
> +	/* The platform device */
> +	struct platform_device		pdev;
> +	struct device			*dev;
> +
> +	/* Hardware resources */
> +	struct reset_control		*rstc;

As long as rstc is only used in dcmipp_probe(), there is no need to
carry it around in struct dcmipp_device.

[...]
> +static int dcmipp_probe(struct platform_device *pdev)
> +{
> +	struct dcmipp_device *dcmipp;
> +	struct clk *kclk;

rstc could be a local variable here.

[...]

> +	/* Get hardware resources from devicetree */
> +	dcmipp->rstc = devm_reset_control_get_exclusive(&pdev->dev, NULL);
> +	if (IS_ERR(dcmipp->rstc))
> +		return dev_err_probe(&pdev->dev, PTR_ERR(dcmipp->rstc),
> +				     "Could not get reset control\n");
[...]
> +	/* Reset device */
> +	ret = reset_control_assert(dcmipp->rstc);
> +	if (ret) {
> +		dev_err(&pdev->dev, "Failed to assert the reset line\n");
> +		return ret;
> +	}
> +
> +	usleep_range(3000, 5000);
> +
> +	ret = reset_control_deassert(dcmipp->rstc);
> +	if (ret) {
> +		dev_err(&pdev->dev, "Failed to deassert the reset line\n");
> +		return ret;
> +	}

regards
Philipp