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V4L/DVB (6184): cx88-alsa: Make volume control stereo
Use the balance control to make the mono volume control stereo. Note that full range isn't supported. The balance control attenuates one channel by 0 to -63 dB, and the volume control provides additional attenuation to both channels by another 0 to -63 dB. So the channel with the most attenuation has a range of 0 to -126 dB, while the other channel only has a range of 0 to -63 dB. ALSA volume controls don't appear to support this concept. I just limited the range to 0 to -63 total. Once you get to -63 dB, you're already at silence, so additional attenuation is pretty much pointless anyway. Signed-off-by: Trent Piepho <xyzzy@speakeasy.org> Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
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@ -552,7 +552,7 @@ static int snd_cx88_capture_volume_info(struct snd_kcontrol *kcontrol,
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struct snd_ctl_elem_info *info)
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{
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info->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
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info->count = 1;
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info->count = 2;
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info->value.integer.min = 0;
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info->value.integer.max = 0x3f;
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@ -565,8 +565,12 @@ static int snd_cx88_capture_volume_get(struct snd_kcontrol *kcontrol,
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{
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snd_cx88_card_t *chip = snd_kcontrol_chip(kcontrol);
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struct cx88_core *core=chip->core;
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int vol = 0x3f - (cx_read(AUD_VOL_CTL) & 0x3f),
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bal = cx_read(AUD_BAL_CTL);
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value->value.integer.value[0] = 0x3f - (cx_read(AUD_VOL_CTL) & 0x3f);
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value->value.integer.value[(bal & 0x40) ? 0 : 1] = vol;
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vol -= (bal & 0x3f);
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value->value.integer.value[(bal & 0x40) ? 1 : 0] = vol < 0 ? 0 : vol;
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return 0;
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}
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@ -577,19 +581,31 @@ static int snd_cx88_capture_volume_put(struct snd_kcontrol *kcontrol,
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{
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snd_cx88_card_t *chip = snd_kcontrol_chip(kcontrol);
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struct cx88_core *core=chip->core;
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int v;
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u32 old_control;
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int v, b;
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int changed = 0;
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u32 old;
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b = value->value.integer.value[1] - value->value.integer.value[0];
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if (b < 0) {
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v = 0x3f - value->value.integer.value[0];
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b = (-b) | 0x40;
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} else {
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v = 0x3f - value->value.integer.value[1];
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}
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/* Do we really know this will always be called with IRQs on? */
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spin_lock_irq(&chip->reg_lock);
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old_control = 0x3f - (cx_read(AUD_VOL_CTL) & 0x3f);
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v = 0x3f - (value->value.integer.value[0] & 0x3f);
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cx_andor(AUD_VOL_CTL, 0x3f, v);
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old = cx_read(AUD_VOL_CTL);
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if (v != (old & 0x3f)) {
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cx_write(AUD_VOL_CTL, (old & ~0x3f) | v);
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changed = 1;
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}
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if (cx_read(AUD_BAL_CTL) != b) {
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cx_write(AUD_BAL_CTL, b);
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changed = 1;
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}
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spin_unlock_irq(&chip->reg_lock);
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return v != old_control;
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return changed;
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}
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static struct snd_kcontrol_new snd_cx88_capture_volume = {
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@ -746,17 +762,12 @@ static int __devinit cx88_audio_initdev(struct pci_dev *pci,
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return (err);
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err = snd_cx88_pcm(chip, 0, "CX88 Digital");
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if (err < 0) {
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snd_card_free(card);
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return (err);
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}
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if (err < 0)
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goto error;
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err = snd_ctl_add(card, snd_ctl_new1(&snd_cx88_capture_volume, chip));
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if (err < 0) {
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snd_card_free(card);
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return (err);
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}
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if (err < 0)
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goto error;
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strcpy (card->driver, "CX88x");
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sprintf(card->shortname, "Conexant CX%x", pci->device);
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@ -768,14 +779,16 @@ static int __devinit cx88_audio_initdev(struct pci_dev *pci,
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card->driver,devno);
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err = snd_card_register(card);
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if (err < 0) {
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snd_card_free(card);
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return (err);
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}
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if (err < 0)
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goto error;
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pci_set_drvdata(pci,card);
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devno++;
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return 0;
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error:
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snd_card_free(card);
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return err;
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}
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/*
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* ALSA destructor
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