[PATCH] ALSA: hda/core: Log stream DMA errors on interrupt

[PATCH] ALSA: hda/core: Log stream DMA errors on interrupt

[Arun Raghavan]

The stream descriptor status register reports FIFO and descriptor
errors, but these are currently cleared silently along with the rest
of the interrupt status. Log them, rate-limited, so DMA problems are
visible instead of only manifesting as audible glitches.

Observed on some AMD GPU HDMI audio controllers under specific low power
circumstances.

Signed-off-by: Arun Raghavan <arunr@valvesoftware.com>
Cc: Arun Raghavan <arun@arunraghavan.net>
---
 sound/hda/core/controller.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/sound/hda/core/controller.c b/sound/hda/core/controller.c
index 69e11d62bbfa..5f1d2c132cec 100644
--- a/sound/hda/core/controller.c
+++ b/sound/hda/core/controller.c
@@ -682,6 +682,11 @@ int snd_hdac_bus_handle_stream_irq(struct hdac_bus *bus, unsigned int status,
 			sd_status = snd_hdac_stream_readb(azx_dev, SD_STS);
 			snd_hdac_stream_writeb(azx_dev, SD_STS, SD_INT_MASK);
 			handled |= 1 << azx_dev->index;
+			if (sd_status & (SD_INT_FIFO_ERR | SD_INT_DESC_ERR)) {
+				dev_warn_ratelimited(bus->dev,
+						"stream %u dma error: 0x%02x\n",
+						azx_dev->index, sd_status);
+			}
 			if ((!azx_dev->substream && !azx_dev->cstream) ||
 			    !azx_dev->running || !(sd_status & SD_INT_COMPLETE))
 				continue;

---
base-commit: 848acc8ffe1b7cd5f1bf427b93069becfebc2c9d
change-id: 20260803-master-48a36c6e70e0

Best regards,
-- 
Arun Raghavan <arunr@valvesoftware.com>

Re: [PATCH] ALSA: hda/core: Log stream DMA errors on interrupt

[Takashi Iwai]

On Tue, 04 Aug 2026 00:07:52 +0200,
Arun Raghavan wrote:
> 
> The stream descriptor status register reports FIFO and descriptor
> errors, but these are currently cleared silently along with the rest
> of the interrupt status. Log them, rate-limited, so DMA problems are
> visible instead of only manifesting as audible glitches.
> 
> Observed on some AMD GPU HDMI audio controllers under specific low power
> circumstances.
> 
> Signed-off-by: Arun Raghavan <arunr@valvesoftware.com>
> Cc: Arun Raghavan <arun@arunraghavan.net>

Applied now to for-next branch.

It's interesting at which situation you get the error bit and which
one.  If it can be used *reliably* for catching a streaming error, the
driver could notify XRUN or error appropriately, too.


thanks,

Takashi