V4L/DVB (9217): si470x: correction of mono/stereo handling

This patch corrects the behavior of mono/stereo indication and
selection.

These functions now work conform to what's defined in the V4L2
specification.

Signed-off-by: Tobias Lorenz <tobias.lorenz@gmx.net>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

1 files changed, 18 insertions, 6 deletions

diff --git a/drivers/media/radio/radio-si470x.c b/drivers/media/radio/radio-si470x.c
index 274d8464c02e..67d74cecdb67 100644
--- a/drivers/media/radio/radio-si470x.c
+++ b/drivers/media/radio/radio-si470x.c
@@ -1431,7 +1431,7 @@ static int si470x_vidioc_g_tuner(struct file *file, void *priv,
         /* driver constants */
         strcpy(tuner->name, "FM");
         tuner->type = V4L2_TUNER_RADIO;
-        tuner->capability = V4L2_TUNER_CAP_LOW;
+        tuner->capability = V4L2_TUNER_CAP_LOW | V4L2_TUNER_CAP_STEREO;
 
         /* range limits */
         switch ((radio->registers[SYSCONFIG2] & SYSCONFIG2_BAND) >> 6) {
@@ -1451,13 +1451,18 @@ static int si470x_vidioc_g_tuner(struct file *file, void *priv,
                 tuner->rangehigh =  90   * FREQ_MUL;
                 break;
         };
-        tuner->rxsubchans = V4L2_TUNER_SUB_MONO | V4L2_TUNER_SUB_STEREO;
 
-        /* Stereo indicator == Stereo (instead of Mono) */
+        /* stereo indicator == stereo (instead of mono) */
         if ((radio->registers[STATUSRSSI] & STATUSRSSI_ST) == 1)
-                tuner->audmode = V4L2_TUNER_MODE_STEREO;
+                tuner->rxsubchans = V4L2_TUNER_SUB_MONO | V4L2_TUNER_SUB_STEREO;
         else
+                tuner->rxsubchans = V4L2_TUNER_SUB_MONO;
+
+        /* mono/stereo selector */
+        if ((radio->registers[POWERCFG] & POWERCFG_MONO) == 1)
                 tuner->audmode = V4L2_TUNER_MODE_MONO;
+        else
+                tuner->audmode = V4L2_TUNER_MODE_STEREO;
 
         /* min is worst, max is best; signal:0..0xffff; rssi: 0..0xff */
         tuner->signal = (radio->registers[STATUSRSSI] & STATUSRSSI_RSSI)
@@ -1492,10 +1497,17 @@ static int si470x_vidioc_s_tuner(struct file *file, void *priv,
         if (tuner->index != 0)
                 goto done;
 
-        if (tuner->audmode == V4L2_TUNER_MODE_MONO)
+        /* mono/stereo selector */
+        switch (tuner->audmode) {
+        case V4L2_TUNER_MODE_MONO:
                 radio->registers[POWERCFG] |= POWERCFG_MONO;  /* force mono */
-        else
+                break;
+        case V4L2_TUNER_MODE_STEREO:
                 radio->registers[POWERCFG] &= ~POWERCFG_MONO; /* try stereo */
+                break;
+        default:
+                goto done;
+        }
 
         retval = si470x_set_register(radio, POWERCFG);