ALSA: usb-audio: Increase max buffer size

[ Upstream commit fee2ec8cceb33b8886bc5894fb07e0b2e34148af ]

The current limit of max buffer size 1MB seems too small for modern
devices with lots of channels and high sample rates.
Let's make bigger, 4MB.

Reviewed-by: Jaroslav Kysela <perex@perex.cz>
Link: https://lore.kernel.org/r/20220407212740.17920-1-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/sound/usb/pcm.c b/sound/usb/pcm.c
index 6fa9115e322b26516f391fae4c5b2e43ffaae444..866a82b69d8d0f21f98492a266b4f0f41fff07f7 100644 (file)
--- a/sound/usb/pcm.c
+++ b/sound/usb/pcm.c
@@ -659,7 +659,7 @@ static int snd_usb_pcm_prepare(struct snd_pcm_substream *substream)
 #define hwc_debug(fmt, args...) do { } while(0)
 #endif
 
-#define MAX_BUFFER_BYTES       (1024 * 1024)
+#define MAX_BUFFER_BYTES       (4 * 1024 * 1024)
 #define MAX_PERIOD_BYTES       (512 * 1024)
 
 static const struct snd_pcm_hardware snd_usb_hardware =