ALSA: snd-atmel-ac97c: set correct size for buffer hardware parameter

This patch will set a proper maximum bytes for the buffer, which is:
channels * bytes per sample * maximum periods * maximum bytes per period.

It also sets the minimum periods to 6, a value chosen from testing, with
a minimum of 6 periods the system has good time to fill in new audio
data without skipping.

Signed-off-by: Hans-Christian Egtvedt <hans-christian.egtvedt@atmel.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
diff --git a/sound/atmel/ac97c.c b/sound/atmel/ac97c.c
index 4e8f66d..c9bc345 100644
--- a/sound/atmel/ac97c.c
+++ b/sound/atmel/ac97c.c
@@ -151,10 +151,10 @@
 	.rate_max		= 48000,
 	.channels_min		= 1,
 	.channels_max		= 2,
-	.buffer_bytes_max	= 64 * 4096,
+	.buffer_bytes_max	= 2 * 2 * 64 * 2048,
 	.period_bytes_min	= 4096,
 	.period_bytes_max	= 4096,
-	.periods_min		= 4,
+	.periods_min		= 6,
 	.periods_max		= 64,
 };