Re: [PATCH] ALSA: intel_hdmi: Check for error num after setting mask

From: Takashi Iwai
Date: Thu Jan 06 2022 - 03:18:04 EST


On Thu, 06 Jan 2022 02:24:28 +0100,
Jiasheng Jiang wrote:
>
> As the dma_supported() may fail, the dma_set_mask_and_coherent() may
> fail too.
> Therefore, it should be better to check it and return error if fails.
>
> Fixes: da8648097497 ("ALSA: x86: Flatten two abstraction layers")
> Signed-off-by: Jiasheng Jiang <jiasheng@xxxxxxxxxxx>

Well, 32bit DMA mask practically never fails on x86 (and other
architectures, IIRC). It's fine to add a sanity check, but it's
better to be mentioned that it never fails.


thanks,

Takashi

> ---
> sound/x86/intel_hdmi_audio.c | 4 +++-
> 1 file changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/sound/x86/intel_hdmi_audio.c b/sound/x86/intel_hdmi_audio.c
> index 33b12aa67cf5..6caea517f07f 100644
> --- a/sound/x86/intel_hdmi_audio.c
> +++ b/sound/x86/intel_hdmi_audio.c
> @@ -1770,7 +1770,9 @@ static int hdmi_lpe_audio_probe(struct platform_device *pdev)
> card_ctx->irq = irq;
>
> /* only 32bit addressable */
> - dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
> + ret = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
> + if (ret)
> + goto err;
>
> init_channel_allocations();
>
> --
> 2.25.1
>