[alsa-devel] [PATCH] ASoC: tegra: Convert to managed resources

[Alexandre Courbot]

On Thu, Aug 13, 2015 at 4:29 PM, Vaishali Thakkar
<vthakkar1994 at gmail.com> wrote:
> Use managed resource functions devm_clk_put and
> devm_snd_soc_register_component to simplify error handling.
>
> To be compatible with the change various gotos are replaced
> with direct returns, and unneeded labels are dropped.
>
> Signed-off-by: Vaishali Thakkar <vthakkar1994 at gmail.com>
> ---
>  sound/soc/tegra/tegra20_spdif.c | 37 +++++++++++++------------------------
>  1 file changed, 13 insertions(+), 24 deletions(-)
>
> diff --git a/sound/soc/tegra/tegra20_spdif.c b/sound/soc/tegra/tegra20_spdif.c
> index 9141477..f69b2e4 100644
> --- a/sound/soc/tegra/tegra20_spdif.c
> +++ b/sound/soc/tegra/tegra20_spdif.c
> @@ -273,45 +273,40 @@ static int tegra20_spdif_platform_probe(struct platform_device *pdev)
>                              GFP_KERNEL);
>         if (!spdif) {
>                 dev_err(&pdev->dev, "Can't allocate tegra20_spdif\n");
> -               ret = -ENOMEM;
> -               goto err;
> +               return -ENOMEM;
>         }
>         dev_set_drvdata(&pdev->dev, spdif);
>
> -       spdif->clk_spdif_out = clk_get(&pdev->dev, "spdif_out");
> +       spdif->clk_spdif_out = devm_clk_get(&pdev->dev, "spdif_out");
>         if (IS_ERR(spdif->clk_spdif_out)) {
>                 pr_err("Can't retrieve spdif clock\n");
>                 ret = PTR_ERR(spdif->clk_spdif_out);
> -               goto err;
> +               return ret;

Maybe do "return PTR_ERR(spdif->clk_spdif_out);" for consistency with
the other error cases of this function?

>         }
>
>         mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
>         if (!mem) {
>                 dev_err(&pdev->dev, "No memory resource\n");
> -               ret = -ENODEV;
> -               goto err_clk_put;
> +               return -ENODEV;
>         }
>
>         dmareq = platform_get_resource(pdev, IORESOURCE_DMA, 0);
>         if (!dmareq) {
>                 dev_err(&pdev->dev, "No DMA resource\n");
> -               ret = -ENODEV;
> -               goto err_clk_put;
> +               return -ENODEV;
>         }
>
>         memregion = devm_request_mem_region(&pdev->dev, mem->start,
>                                             resource_size(mem), DRV_NAME);
>         if (!memregion) {
>                 dev_err(&pdev->dev, "Memory region already claimed\n");
> -               ret = -EBUSY;
> -               goto err_clk_put;
> +               return -EBUSY;
>         }
>
>         regs = devm_ioremap(&pdev->dev, mem->start, resource_size(mem));
>         if (!regs) {
>                 dev_err(&pdev->dev, "ioremap failed\n");
> -               ret = -ENOMEM;
> -               goto err_clk_put;
> +               return -ENOMEM;
>         }
>
>         spdif->regmap = devm_regmap_init_mmio(&pdev->dev, regs,
> @@ -319,7 +314,7 @@ static int tegra20_spdif_platform_probe(struct platform_device *pdev)
>         if (IS_ERR(spdif->regmap)) {
>                 dev_err(&pdev->dev, "regmap init failed\n");
>                 ret = PTR_ERR(spdif->regmap);
> -               goto err_clk_put;
> +               return ret;

Same here.

>         }
>
>         spdif->playback_dma_data.addr = mem->start + TEGRA20_SPDIF_DATA_OUT;
> @@ -334,8 +329,9 @@ static int tegra20_spdif_platform_probe(struct platform_device *pdev)
>                         goto err_pm_disable;
>         }
>
> -       ret = snd_soc_register_component(&pdev->dev, &tegra20_spdif_component,
> -                                  &tegra20_spdif_dai, 1);
> +       ret = devm_snd_soc_register_component(&pdev->dev,
> +                                             &tegra20_spdif_component,
> +                                             &tegra20_spdif_dai, 1);
>         if (ret) {
>                 dev_err(&pdev->dev, "Could not register DAI: %d\n", ret);
>                 ret = -ENOMEM;
> @@ -345,21 +341,17 @@ static int tegra20_spdif_platform_probe(struct platform_device *pdev)
>         ret = tegra_pcm_platform_register(&pdev->dev);
>         if (ret) {
>                 dev_err(&pdev->dev, "Could not register PCM: %d\n", ret);
> -               goto err_unregister_component;
> +               return ret;

In the previous code, PM cleanup was also performed after the
component was unregistered. If you return directly, this is not
performed anymore - I think you should "goto err_suspend;" here.

This will change the ordering of cleanup operations though - e.g.
snd_soc_unregister_component() will now be called *after* PM cleanup.
Are things still working ok after this? (I suppose they do considering
how simple the PM ops are, but it might be worth testing).