[ALSA] ymfpci: fix swapped channels in SPDIF output

Modules: YMFPCI driver

The routing of the effect 2/3 channels to the digital output is the
opposite of the rear analog output (left/right swapped).

We make the order correct for the digital output (which will make the
analog rear have the channels swapped) to make AC3 output work.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>

1 files changed, 8 insertions, 4 deletions

diff --git a/sound/pci/ymfpci/ymfpci_main.c b/sound/pci/ymfpci/ymfpci_main.c
index a1aa74b79b3d..30ee53adb494 100644
--- a/sound/pci/ymfpci/ymfpci_main.c
+++ b/sound/pci/ymfpci/ymfpci_main.c
@@ -536,13 +536,17 @@ static void snd_ymfpci_pcm_init_voice(struct snd_ymfpci_pcm *ypcm, unsigned int
                         }
                 }
                 if (ypcm->output_rear) {
+                        /* The SPDIF out channels seem to be swapped, so we have
+                         * to swap them here, too.  The rear analog out channels
+                         * will be wrong, but otherwise AC3 would not work.
+                         */
                         if (use_left) {
-                                bank->eff2_gain =
-                                bank->eff2_gain_end = vol_left;
+                                bank->eff3_gain =
+                                bank->eff3_gain_end = vol_left;
                         }
                         if (use_right) {
-                                bank->eff3_gain =
-                                bank->eff3_gain_end = vol_right;
+                                bank->eff2_gain =
+                                bank->eff2_gain_end = vol_right;
                         }
                 }
         }