[PATCH -next] drm: xlnx: zynqmp_dpsub: Use devm_clk_get_enabled() helper function

[Laurent Pinchart]

Hi Jinjie,

(CC'ing Tomi)

Thank you for the patch.

On Fri, Aug 25, 2023 at 03:23:24PM +0800, Jinjie Ruan wrote:
> The devm_clk_get_enabled() helper:
>     - calls devm_clk_get()
>     - calls clk_prepare_enable() and registers what is needed in order to
>       call clk_disable_unprepare() when needed, as a managed resource.
> 
> This simplifies the code.

While this indeed simplifies the code, I think we should instead control
the clock dynamically at runtime.

I don't have access to the hardware at the moment. Tomi, would you be
able to give this a go ? I can also write a patch and let you test it if
desired.

> Signed-off-by: Jinjie Ruan <ruanjinjie at huawei.com>
> ---
>  drivers/gpu/drm/xlnx/zynqmp_dpsub.c | 14 +++-----------
>  1 file changed, 3 insertions(+), 11 deletions(-)
> 
> diff --git a/drivers/gpu/drm/xlnx/zynqmp_dpsub.c b/drivers/gpu/drm/xlnx/zynqmp_dpsub.c
> index 88eb33acd5f0..92e61434473f 100644
> --- a/drivers/gpu/drm/xlnx/zynqmp_dpsub.c
> +++ b/drivers/gpu/drm/xlnx/zynqmp_dpsub.c
> @@ -92,16 +92,10 @@ unsigned int zynqmp_dpsub_get_audio_clk_rate(struct zynqmp_dpsub *dpsub)
>  
>  static int zynqmp_dpsub_init_clocks(struct zynqmp_dpsub *dpsub)
>  {
> -	int ret;
> -
> -	dpsub->apb_clk = devm_clk_get(dpsub->dev, "dp_apb_clk");
> -	if (IS_ERR(dpsub->apb_clk))
> -		return PTR_ERR(dpsub->apb_clk);
> -
> -	ret = clk_prepare_enable(dpsub->apb_clk);
> -	if (ret) {
> +	dpsub->apb_clk = devm_clk_get_enabled(dpsub->dev, "dp_apb_clk");
> +	if (IS_ERR(dpsub->apb_clk)) {
>  		dev_err(dpsub->dev, "failed to enable the APB clock\n");
> -		return ret;
> +		return PTR_ERR(dpsub->apb_clk);
>  	}
>  
>  	/*
> @@ -274,7 +268,6 @@ static int zynqmp_dpsub_probe(struct platform_device *pdev)
>  	zynqmp_dp_remove(dpsub);
>  err_pm:
>  	pm_runtime_disable(&pdev->dev);
> -	clk_disable_unprepare(dpsub->apb_clk);
>  err_mem:
>  	of_reserved_mem_device_release(&pdev->dev);
>  	if (!dpsub->drm)
> @@ -295,7 +288,6 @@ static void zynqmp_dpsub_remove(struct platform_device *pdev)
>  	zynqmp_dp_remove(dpsub);
>  
>  	pm_runtime_disable(&pdev->dev);
> -	clk_disable_unprepare(dpsub->apb_clk);
>  	of_reserved_mem_device_release(&pdev->dev);
>  
>  	if (!dpsub->drm)

-- 
Regards,

Laurent Pinchart