From 9ef04066b3e7c51ed7edc6010ac039f18f9f3617 Mon Sep 17 00:00:00 2001 From: Clemens Ladisch Date: Tue, 25 May 2010 09:03:40 +0200 Subject: [PATCH 1/1] ALSA: hda_intel: fix handling of non-completion stream interrupts Check that the interrupt raised for a stream is actually a buffer completion interrupt before handling it as one. Otherwise, memory errors or FIFO xruns would be interpreted as a pointer update and could break the stream timing. Signed-off-by: Clemens Ladisch Signed-off-by: Takashi Iwai --- sound/pci/hda/hda_intel.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/sound/pci/hda/hda_intel.c b/sound/pci/hda/hda_intel.c index 14d895b..77e22c2 100644 --- a/sound/pci/hda/hda_intel.c +++ b/sound/pci/hda/hda_intel.c @@ -1097,6 +1097,7 @@ static irqreturn_t azx_interrupt(int irq, void *dev_id) struct azx *chip = dev_id; struct azx_dev *azx_dev; u32 status; + u8 sd_status; int i, ok; spin_lock(&chip->reg_lock); @@ -1110,8 +1111,10 @@ static irqreturn_t azx_interrupt(int irq, void *dev_id) for (i = 0; i < chip->num_streams; i++) { azx_dev = &chip->azx_dev[i]; if (status & azx_dev->sd_int_sta_mask) { + sd_status = azx_sd_readb(azx_dev, SD_STS); azx_sd_writeb(azx_dev, SD_STS, SD_INT_MASK); - if (!azx_dev->substream || !azx_dev->running) + if (!azx_dev->substream || !azx_dev->running || + !(sd_status & SD_INT_COMPLETE)) continue; /* check whether this IRQ is really acceptable */ ok = azx_position_ok(chip, azx_dev); -- 1.8.2.3