ALSA: hda - Add Kconfig for the default buffer size
Add a Kconfig entry to specify the default buffer size.
Distros using PulseAudio can choose a larger value here.
Signed-off-by: Takashi Iwai <tiwai@suse.de>
diff --git a/sound/pci/hda/Kconfig b/sound/pci/hda/Kconfig
index 70762fc..1f1a4ae 100644
--- a/sound/pci/hda/Kconfig
+++ b/sound/pci/hda/Kconfig
@@ -14,6 +14,19 @@
if SND_HDA_INTEL
+config SND_HDA_PREALLOC_SIZE
+ int "Pre-allocated buffer size for HD-audio driver"
+ range 0 32768
+ default 64
+ help
+ Speficies the default pre-allocated buffer-size in kB for
+ HD-audio driver. A larger buffer (e.g. 2048) is preferred
+ for systems with PulseAudio. The default 64 is chosen just
+ from the compatibility reason.
+
+ Note that the pre-allocation size can be changed dynamically
+ via a proc file (/proc/asound/card*/pcm*/sub*/prealloc), too.
+
config SND_HDA_HWDEP
bool "Build hwdep interface for HD-audio driver"
select SND_HWDEP
diff --git a/sound/pci/hda/hda_intel.c b/sound/pci/hda/hda_intel.c
index 25619cd..5ce9531 100644
--- a/sound/pci/hda/hda_intel.c
+++ b/sound/pci/hda/hda_intel.c
@@ -2075,6 +2075,8 @@
}
}
+#define MAX_PREALLOC_SIZE (32 * 1024 * 1024)
+
static int
azx_attach_pcm_stream(struct hda_bus *bus, struct hda_codec *codec,
struct hda_pcm *cpcm)
@@ -2083,6 +2085,7 @@
struct snd_pcm *pcm;
struct azx_pcm *apcm;
int pcm_dev = cpcm->device;
+ unsigned int size;
int s, err;
if (pcm_dev >= HDA_MAX_PCMS) {
@@ -2118,9 +2121,12 @@
snd_pcm_set_ops(pcm, s, &azx_pcm_ops);
}
/* buffer pre-allocation */
+ size = CONFIG_SND_HDA_PREALLOC_SIZE * 1024;
+ if (size > MAX_PREALLOC_SIZE)
+ size = MAX_PREALLOC_SIZE;
snd_pcm_lib_preallocate_pages_for_all(pcm, SNDRV_DMA_TYPE_DEV_SG,
snd_dma_pci_data(chip->pci),
- 1024 * 64, 32 * 1024 * 1024);
+ size, MAX_PREALLOC_SIZE);
return 0;
}