+static void snd_m3_update_hw_volume(unsigned long private_data)
+{
+ m3_t *chip = (m3_t *) private_data;
+ int x, val;
+ unsigned long flags;
+
+ /* Figure out which volume control button was pushed,
+ based on differences from the default register
+ values. */
+ x = inb(chip->iobase + SHADOW_MIX_REG_VOICE) & 0xee;
+
+ /* Reset the volume control registers. */
+ outb(0x88, chip->iobase + SHADOW_MIX_REG_VOICE);
+ outb(0x88, chip->iobase + HW_VOL_COUNTER_VOICE);
+ outb(0x88, chip->iobase + SHADOW_MIX_REG_MASTER);
+ outb(0x88, chip->iobase + HW_VOL_COUNTER_MASTER);
+
+ if (!chip->master_switch || !chip->master_volume)
+ return;
+
+ /* FIXME: we can't call snd_ac97_* functions since here is in tasklet. */
+ spin_lock_irqsave(&chip->ac97_lock, flags);
+
+ val = chip->ac97->regs[AC97_MASTER_VOL];
+ switch (x) {
+ case 0x88:
+ /* mute */
+ val ^= 0x8000;
+ chip->ac97->regs[AC97_MASTER_VOL] = val;
+ outw(val, chip->iobase + CODEC_DATA);
+ outb(AC97_MASTER_VOL, chip->iobase + CODEC_COMMAND);
+ snd_ctl_notify(chip->card, SNDRV_CTL_EVENT_MASK_VALUE,
+ &chip->master_switch->id);
+ break;
+ case 0xaa:
+ /* volume up */
+ if ((val & 0x7f) > 0)
+ val--;
+ if ((val & 0x7f00) > 0)
+ val -= 0x0100;
+ chip->ac97->regs[AC97_MASTER_VOL] = val;
+ outw(val, chip->iobase + CODEC_DATA);
+ outb(AC97_MASTER_VOL, chip->iobase + CODEC_COMMAND);
+ snd_ctl_notify(chip->card, SNDRV_CTL_EVENT_MASK_VALUE,
+ &chip->master_volume->id);
+ break;
+ case 0x66:
+ /* volume down */
+ if ((val & 0x7f) < 0x1f)
+ val++;
+ if ((val & 0x7f00) < 0x1f00)
+ val += 0x0100;
+ chip->ac97->regs[AC97_MASTER_VOL] = val;
+ outw(val, chip->iobase + CODEC_DATA);
+ outb(AC97_MASTER_VOL, chip->iobase + CODEC_COMMAND);
+ snd_ctl_notify(chip->card, SNDRV_CTL_EVENT_MASK_VALUE,
+ &chip->master_volume->id);
+ break;
+ }
+ spin_unlock_irqrestore(&chip->ac97_lock, flags);
+}
+