V4L/DVB (4872): Saa7134-alsa improvements

The change does the following:
- At device open, it sets the recording source to the current
  input instead of LINE2. So it is no longer necessary to set the
  recording source with a mixer application.
- Connects the mixer volume control to the input sensitivity selection
  of the analog sound inputs. This allows only one 6db step.
Signed-off-by: NHartmut Hackmann <hartmut.hackmann@t-online.de>
Signed-off-by: NMauro Carvalho Chehab <mchehab@infradead.org>

drivers/media/video/saa7134/saa7134-alsa.c

 /*
  *   SAA713x ALSA support for V4L
  *
- *
- *   Caveats:
- *        - Volume doesn't work (it's always at max)
- *
  *   This program is free software; you can redistribute it and/or modify
  *   it under the terms of the GNU General Public License as published by
  *   the Free Software Foundation, version 2
@@ -614,13 +610,18 @@ static int snd_card_saa7134_capture_open(struct snd_pcm_substream * substream)
 	snd_card_saa7134_pcm_t *pcm;
 	snd_card_saa7134_t *saa7134 = snd_pcm_substream_chip(substream);
 	struct saa7134_dev *dev = saa7134->dev;
-	int err;
+	int amux, err;
 
 	mutex_lock(&dev->dmasound.lock);
 
 	dev->dmasound.read_count  = 0;
 	dev->dmasound.read_offset = 0;
 
+	amux = dev->input->amux;
+	if ((amux < 1) || (amux > 3))
+		amux = 1;
+	dev->dmasound.input  =  amux - 1;
+
 	mutex_unlock(&dev->dmasound.lock);
 
 	pcm = kzalloc(sizeof(*pcm), GFP_KERNEL);
@@ -713,6 +714,8 @@ static int snd_saa7134_volume_put(struct snd_kcontrol * kcontrol,
 				  struct snd_ctl_elem_value * ucontrol)
 {
 	snd_card_saa7134_t *chip = snd_kcontrol_chip(kcontrol);
+	struct saa7134_dev *dev = chip->dev;
+
 	int change, addr = kcontrol->private_value;
 	int left, right;
 
@@ -727,10 +730,52 @@ static int snd_saa7134_volume_put(struct snd_kcontrol * kcontrol,
 	if (right > 20)
 		right = 20;
 	spin_lock_irq(&chip->mixer_lock);
-	change = chip->mixer_volume[addr][0] != left ||
-		 chip->mixer_volume[addr][1] != right;
-	chip->mixer_volume[addr][0] = left;
-	chip->mixer_volume[addr][1] = right;
+	change = 0;
+	if (chip->mixer_volume[addr][0] != left) {
+		change = 1;
+		right = left;
+	}
+	if (chip->mixer_volume[addr][1] != right) {
+		change = 1;
+		left = right;
+	}
+	if (change) {
+		switch (dev->pci->device) {
+			case PCI_DEVICE_ID_PHILIPS_SAA7134:
+				switch (addr) {
+					case MIXER_ADDR_TVTUNER:
+						left = 20;
+						break;
+					case MIXER_ADDR_LINE1:
+						saa_andorb(SAA7134_ANALOG_IO_SELECT,  0x10,
+							   (left > 10) ? 0x00 : 0x10);
+						break;
+					case MIXER_ADDR_LINE2:
+						saa_andorb(SAA7134_ANALOG_IO_SELECT,  0x20,
+							   (left > 10) ? 0x00 : 0x20);
+						break;
+				}
+				break;
+			case PCI_DEVICE_ID_PHILIPS_SAA7133:
+			case PCI_DEVICE_ID_PHILIPS_SAA7135:
+				switch (addr) {
+					case MIXER_ADDR_TVTUNER:
+						left = 20;
+						break;
+					case MIXER_ADDR_LINE1:
+						saa_andorb(0x0594,  0x10,
+							   (left > 10) ? 0x00 : 0x10);
+						break;
+					case MIXER_ADDR_LINE2:
+						saa_andorb(0x0594,  0x20,
+							   (left > 10) ? 0x00 : 0x20);
+						break;
+				}
+				break;
+		}
+		chip->mixer_volume[addr][0] = left;
+		chip->mixer_volume[addr][1] = right;
+	}
 	spin_unlock_irq(&chip->mixer_lock);
 	return change;
 }