2001-02-21 16:48:16

by Jeff Garzik

Subject: PATCH: Via audio rate lock, for testing

Can you guys test this patch, and let me know if it fixes Via audio
problems on your kernel?

It should apply against 2.4.1 or 2.4.1-acXX kernels. Note that it
should be applied with "patch -p0" while in the linux kernel source
directory, not applied with "patch -p1".

Regards,

Jeff




Index: drivers/sound/via82cxxx_audio.c
===================================================================
RCS file: /cvsroot/gkernel/linux_2_4/drivers/sound/via82cxxx_audio.c,v
retrieving revision 1.1.1.13.22.1
diff -u -r1.1.1.13.22.1 via82cxxx_audio.c
--- drivers/sound/via82cxxx_audio.c 2001/02/18 23:58:28 1.1.1.13.22.1
+++ drivers/sound/via82cxxx_audio.c 2001/02/21 16:36:23
@@ -281,6 +281,8 @@

int dev_dsp; /* /dev/dsp index from register_sound_dsp() */

+ int locked_rate : 1;
+
struct semaphore syscall_sem;
struct semaphore open_sem;

@@ -503,10 +505,16 @@
static int via_set_rate (struct ac97_codec *ac97,
struct via_channel *chan, unsigned rate)
{
+ struct via_info *card = ac97->private_data;
int rate_reg;

DPRINTK ("ENTER, rate = %d\n", rate);

+ if (card->locked_rate) {
+ chan->rate = 48000;
+ goto out;
+ }
+
if (rate > 48000) rate = 48000;
if (rate < 4000) rate = 4000;

@@ -530,6 +538,13 @@
*/
chan->rate = via_ac97_read_reg (ac97, rate_reg);

+ if (chan->rate == 0) {
+ card->locked_rate = 1;
+ chan->rate = 48000;
+ printk (KERN_WARNING PFX "Codec rate locked at 48Khz\n");
+ }
+
+out:
DPRINTK ("EXIT, returning rate %d Hz\n", chan->rate);
return chan->rate;
}
@@ -1438,7 +1453,7 @@
* via_ac97_reset - Reset Via AC97 hardware
* @card: Private info for specified board
*
- * Reset Via AC97 hardware.
+ * Reset Via AC97 codec, controller, and hardware.
*/

static int __init via_ac97_reset (struct via_info *card)
@@ -1512,8 +1527,8 @@
*/

/* enable variable rate, variable rate MIC ADC */
- tmp16 = via_ac97_read_reg (&card->ac97, 0x2A);
- via_ac97_write_reg (&card->ac97, 0x2A, tmp16 | (1<<0));
+ tmp16 = via_ac97_read_reg (&card->ac97, AC97_EXTENDED_STATUS);
+ via_ac97_write_reg (&card->ac97, AC97_EXTENDED_STATUS, tmp16 | 1);

pci_read_config_byte (pdev, VIA_ACLINK_CTRL, &tmp8);
if ((tmp8 & (VIA_CR41_AC97_ENABLE | VIA_CR41_AC97_RESET)) == 0) {
@@ -1588,8 +1603,22 @@
}

/* enable variable rate, variable rate MIC ADC */
- tmp16 = via_ac97_read_reg (&card->ac97, 0x2A);
- via_ac97_write_reg (&card->ac97, 0x2A, tmp16 | (1<<0));
+ tmp16 = via_ac97_read_reg (&card->ac97, AC97_EXTENDED_STATUS);
+ via_ac97_write_reg (&card->ac97, AC97_EXTENDED_STATUS, tmp16 | 1);
+
+ /*
+ * If we cannot enable VRA, we have a locked-rate codec.
+ * We try again to enable VRA before assuming so, however.
+ */
+ tmp16 = via_ac97_read_reg (&card->ac97, AC97_EXTENDED_STATUS);
+ if ((tmp16 & 1) == 0) {
+ via_ac97_write_reg (&card->ac97, AC97_EXTENDED_STATUS, tmp16 | 1);
+ tmp16 = via_ac97_read_reg (&card->ac97, AC97_EXTENDED_STATUS);
+ if ((tmp16 & 1) == 0) {
+ card->locked_rate = 1;
+ printk (KERN_WARNING PFX "Codec rate locked at 48Khz\n");
+ }
+ }

DPRINTK ("EXIT, returning 0\n");
return 0;