V4L/DVB (7163): em28xx: makes audio settings more stable

Improves audio configurations on em28xx:
        - mutes audio before changing amux;
        - adds a delay after setting audio src;
        - waits up to 50ms for ac97 busy.

Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>

diff --git a/drivers/media/video/em28xx/em28xx-core.c b/drivers/media/video/em28xx/em28xx-core.c
index 6965bafe54a1372a116c34151a9645a4c03cb8c1..275f1e936304fd151087f9bbc590a3a54f951cc6 100644 (file)
--- a/drivers/media/video/em28xx/em28xx-core.c
+++ b/drivers/media/video/em28xx/em28xx-core.c
@@ -255,21 +255,26 @@ static int em28xx_write_reg_bits(struct em28xx *dev, u16 reg, u8 val,
  */
 static int em28xx_write_ac97(struct em28xx *dev, u8 reg, u8 *val)
 {
-       int ret;
+       int ret, i;
        u8 addr = reg & 0x7f;
        if ((ret = em28xx_write_regs(dev, AC97LSB_REG, val, 2)) < 0)
                return ret;
        if ((ret = em28xx_write_regs(dev, AC97ADDR_REG, &addr, 1)) < 0)
                return ret;
-       if ((ret = em28xx_read_reg(dev, AC97BUSY_REG)) < 0)
-               return ret;
-       else if (((u8) ret) & 0x01) {
-               em28xx_warn ("AC97 command still being executed: not handled properly!\n");
+
+       /* Wait up to 50 ms for AC97 command to complete */
+       for (i = 0; i < 10; i++) {
+               if ((ret = em28xx_read_reg(dev, AC97BUSY_REG)) < 0)
+                       return ret;
+               if (!((u8) ret) & 0x01)
+                       return 0;
+               msleep(5);
        }
+       em28xx_warn ("AC97 command still being executed: not handled properly!\n");
        return 0;
 }
 
-int em28xx_set_audio_source(struct em28xx *dev)
+static int em28xx_set_audio_source(struct em28xx *dev)
 {
        static char *enable  = "\x08\x08";
        static char *disable = "\x08\x88";
@@ -312,6 +317,7 @@ int em28xx_set_audio_source(struct em28xx *dev)
        ret = em28xx_write_reg_bits(dev, AUDIOSRC_REG, input, 0xc0);
        if (ret < 0)
                return ret;
+       msleep(5);
 
        /* Sets AC97 mixer registers
           This is seems to be needed, even for non-ac97 configs
@@ -334,9 +340,10 @@ int em28xx_audio_analog_set(struct em28xx *dev)
        s[0] |= 0x1f - dev->volume;
        s[1] |= 0x1f - dev->volume;
 
-       if (dev->mute)
-               s[1] |= 0x80;
+       /* Mute */
+       s[1] |= 0x80;
        ret = em28xx_write_ac97(dev, MASTER_AC97, s);
+
        if (ret < 0)
                return ret;
 
@@ -354,6 +361,11 @@ int em28xx_audio_analog_set(struct em28xx *dev)
        /* Selects the proper audio input */
        ret = em28xx_set_audio_source(dev);
 
+       /* Unmute device */
+       if (!dev->mute)
+               s[1] &= ~0x80;
+       ret = em28xx_write_ac97(dev, MASTER_AC97, s);
+
        return ret;
 }
 EXPORT_SYMBOL_GPL(em28xx_audio_analog_set);

diff --git a/drivers/media/video/em28xx/em28xx-video.c b/drivers/media/video/em28xx/em28xx-video.c
index f69f591eeaf6fc768245d6b5854638f3f1407796..eeda3b2faec8a723f93f09c490b6bd124bb7c964 100644 (file)
--- a/drivers/media/video/em28xx/em28xx-video.c
+++ b/drivers/media/video/em28xx/em28xx-video.c
@@ -189,7 +189,7 @@ static void video_mux(struct em28xx *dev, int index)
                em28xx_i2c_call_clients(dev, VIDIOC_INT_S_AUDIO_ROUTING, &route);
        }
 
-       em28xx_set_audio_source(dev);
+       em28xx_audio_analog_set(dev);
 }
 
 /* Usage lock check functions */
@@ -837,7 +837,6 @@ static int em28xx_reg_len(int reg)
        case AC97LSB_REG:
        case HSCALELOW_REG:
        case VSCALELOW_REG:
-
                return 2;
        default:
                return 1;