[media] tvaudio: fix broken volume/balance calculations

The balance control did not do what it is supposed to do due to wrong
calculations.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

1 files changed, 27 insertions, 38 deletions

diff --git a/drivers/media/i2c/tvaudio.c b/drivers/media/i2c/tvaudio.c
index 3b24d3fc1866..d5cd2eb95558 100644
--- a/drivers/media/i2c/tvaudio.c
+++ b/drivers/media/i2c/tvaudio.c
@@ -93,8 +93,8 @@ struct CHIPDESC {
         /* which register has which value */
         int    leftreg,rightreg,treblereg,bassreg;
 
-        /* initialize with (defaults to 65535/65535/32768/32768 */
-        int    leftinit,rightinit,trebleinit,bassinit;
+        /* initialize with (defaults to 65535/32768/32768 */
+        int    volinit, trebleinit, bassinit;
 
         /* functions to convert the values (v4l -> chip) */
         getvalue volfunc,treblefunc,bassfunc;
@@ -122,7 +122,7 @@ struct CHIPSTATE {
         audiocmd   shadow;
 
         /* current settings */
-        __u16 left, right, treble, bass, muted;
+        u16 volume, balance, treble, bass, muted;
         int prevmode;
         int radio;
         int input;
@@ -1523,8 +1523,7 @@ static struct CHIPDESC chiplist[] = {
                 .rightreg   = TDA9875_MVR,
                 .bassreg    = TDA9875_MBA,
                 .treblereg  = TDA9875_MTR,
-                .leftinit   = 58880,
-                .rightinit  = 58880,
+                .volinit    = 58880,
         },
         {
                 .name       = "tda9850",
@@ -1694,20 +1693,13 @@ static int tvaudio_g_ctrl(struct v4l2_subdev *sd,
         case V4L2_CID_AUDIO_VOLUME:
                 if (!(desc->flags & CHIP_HAS_VOLUME))
                         break;
-                ctrl->value = max(chip->left,chip->right);
+                ctrl->value = chip->volume;
                 return 0;
         case V4L2_CID_AUDIO_BALANCE:
-        {
-                int volume;
                 if (!(desc->flags & CHIP_HAS_VOLUME))
                         break;
-                volume = max(chip->left,chip->right);
-                if (volume)
-                        ctrl->value=(32768*min(chip->left,chip->right))/volume;
-                else
-                        ctrl->value=32768;
+                ctrl->value = chip->balance;
                 return 0;
-        }
         case V4L2_CID_AUDIO_BASS:
                 if (!(desc->flags & CHIP_HAS_BASSTREBLE))
                         break;
@@ -1744,41 +1736,38 @@ static int tvaudio_s_ctrl(struct v4l2_subdev *sd,
                 return 0;
         case V4L2_CID_AUDIO_VOLUME:
         {
-                int volume,balance;
+                u32 volume, balance;
+                u32 left, right;
 
                 if (!(desc->flags & CHIP_HAS_VOLUME))
                         break;
 
-                volume = max(chip->left,chip->right);
-                if (volume)
-                        balance=(32768*min(chip->left,chip->right))/volume;
-                else
-                        balance=32768;
-
-                volume=ctrl->value;
-                chip->left = (min(65536 - balance,32768) * volume) / 32768;
-                chip->right = (min(balance,volume *(__u16)32768)) / 32768;
-
-                chip_write(chip,desc->leftreg,desc->volfunc(chip->left));
-                chip_write(chip,desc->rightreg,desc->volfunc(chip->right));
+                volume = ctrl->value;
+                chip->volume = volume;
+                balance = chip->balance;
+                left = (min(65536U - balance, 32768U) * volume) / 32768U;
+                right = (min(balance, 32768U) * volume) / 32768U;
 
+                chip_write(chip, desc->leftreg, desc->volfunc(left));
+                chip_write(chip, desc->rightreg, desc->volfunc(right));
                 return 0;
         }
         case V4L2_CID_AUDIO_BALANCE:
         {
-                int volume, balance;
+                u32 volume, balance;
+                u32 left, right;
 
                 if (!(desc->flags & CHIP_HAS_VOLUME))
                         break;
 
-                volume = max(chip->left, chip->right);
                 balance = ctrl->value;
-                chip->left = (min(65536 - balance, 32768) * volume) / 32768;
-                chip->right = (min(balance, volume * (__u16)32768)) / 32768;
-
-                chip_write(chip, desc->leftreg, desc->volfunc(chip->left));
-                chip_write(chip, desc->rightreg, desc->volfunc(chip->right));
+                chip->balance = balance;
+                volume = chip->volume;
+                left = (min(65536U - balance, 32768U) * volume) / 32768U;
+                right = (min(balance, 32768U) * volume) / 32768U;
 
+                chip_write(chip, desc->leftreg, desc->volfunc(left));
+                chip_write(chip, desc->rightreg, desc->volfunc(right));
                 return 0;
         }
         case V4L2_CID_AUDIO_BASS:
@@ -2043,12 +2032,12 @@ static int tvaudio_probe(struct i2c_client *client, const struct i2c_device_id *
                         v4l2_info(sd, "volume callback undefined!\n");
                         desc->flags &= ~CHIP_HAS_VOLUME;
                 } else {
-                        chip->left  = desc->leftinit  ? desc->leftinit  : 65535;
-                        chip->right = desc->rightinit ? desc->rightinit : 65535;
+                        chip->volume = desc->volinit ? desc->volinit : 65535;
+                        chip->balance = 32768;
                         chip_write(chip, desc->leftreg,
-                                   desc->volfunc(chip->left));
+                                   desc->volfunc(chip->volume));
                         chip_write(chip, desc->rightreg,
-                                   desc->volfunc(chip->right));
+                                   desc->volfunc(chip->volume));
                 }
         }
         if (desc->flags & CHIP_HAS_BASSTREBLE) {