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

[Vaishali Thakkar]

On Mon, Aug 17, 2015 at 12:47 PM, Alexandre Courbot <gnurou at gmail.com> wrote:
> 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.

Actually people prefer to write this way when they are calling PTR_ERR
more than one time for the same value. But as for this file at both places
we are calling PTR_ERR for different values, may be we can directly call
it in return.

>>         }
>>
>>         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).

I think you are right. I missed that. But now thing is , this patch is already
applied here:
https://git.kernel.org/cgit/linux/kernel/git/broonie/sound.git/commit/?h=topic/tegra

I am not sure if now I can change version 2 with the changes you suggested
or not. Although I will not be able to test it  after changing 'goto
err_suspend'
as I don't have hardware but may be someone else can test it.

-- 
Vaishali