ALSA: intel8x0: implement ac97_clock whitelist

The AC97 clock detection is not accurate in some cases. This patch adds
an initial whitelist for audio devices gathered from RedHat's bugzilla:

https://bugzilla.redhat.com/show_bug.cgi?id=441087

As a side effect, white-listing might speedup kernel booting (AC97 clock
measuring code is not activated).

Signed-off-by: Jaroslav Kysela <perex@perex.cz>
This commit is contained in:
Jaroslav Kysela 2008-08-29 11:29:39 +02:00
parent d886e87cb8
commit 2b3b5485aa
1 changed files with 41 additions and 3 deletions

View File

@ -83,7 +83,7 @@ MODULE_PARM_DESC(index, "Index value for Intel i8x0 soundcard.");
module_param(id, charp, 0444);
MODULE_PARM_DESC(id, "ID string for Intel i8x0 soundcard.");
module_param(ac97_clock, int, 0444);
MODULE_PARM_DESC(ac97_clock, "AC'97 codec clock (0 = auto-detect).");
MODULE_PARM_DESC(ac97_clock, "AC'97 codec clock (0 = whitelist + auto-detect, 1 = force autodetect).");
module_param(ac97_quirk, charp, 0444);
MODULE_PARM_DESC(ac97_quirk, "AC'97 workaround for strange hardware.");
module_param(buggy_semaphore, bool, 0444);
@ -2692,6 +2692,38 @@ static void __devinit intel8x0_measure_ac97_clock(struct intel8x0 *chip)
snd_ac97_update_power(chip->ac97[0], AC97_PCM_FRONT_DAC_RATE, 0);
}
struct intel8x0_clock_list {
unsigned short subvendor;
unsigned short subdevice;
unsigned int rate;
};
static struct intel8x0_clock_list intel8x0_clock_list[] __devinitdata = {
{ 0x0e11, 0x008a, 41000 }, /* Analog Devices AD1885 */
{ 0x1028, 0x00be, 44100 }, /* Analog Devices AD1885 */
{ 0x1028, 0x0177, 48000 }, /* Analog Devices AD1980 */
{ 0x1043, 0x80f3, 48000 }, /* Analog Devices AD1985 */
{ 0x0000, 0x0000, 00000 } /* terminator */
};
static int __devinit intel8x0_in_clock_list(struct intel8x0 *chip)
{
struct pci_dev *pci = chip->pci;
struct intel8x0_clock_list *wl;
for (wl = intel8x0_clock_list; wl->subvendor; wl++) {
if (wl->subvendor == pci->subsystem_vendor &&
wl->subdevice == pci->subsystem_device) {
printk(KERN_INFO "intel8x0: white list rate for %04x:%04x is %i\n",
pci->subsystem_vendor,
pci->subsystem_device, wl->rate);
chip->ac97_bus->clock = wl->rate;
return 1;
}
}
return 0;
}
#ifdef CONFIG_PROC_FS
static void snd_intel8x0_proc_read(struct snd_info_entry * entry,
struct snd_info_buffer *buffer)
@ -3087,8 +3119,14 @@ static int __devinit snd_intel8x0_probe(struct pci_dev *pci,
"%s with %s at irq %i", card->shortname,
snd_ac97_get_short_name(chip->ac97[0]), chip->irq);
if (! ac97_clock)
intel8x0_measure_ac97_clock(chip);
if (ac97_clock == 0 || ac97_clock == 1) {
if (ac97_clock == 0) {
if (intel8x0_in_clock_list(chip) == 0)
intel8x0_measure_ac97_clock(chip);
} else {
intel8x0_measure_ac97_clock(chip);
}
}
if ((err = snd_card_register(card)) < 0) {
snd_card_free(card);