[alsa-devel] Scarlett 6i6 gain switches patch

[Jens Verwiebe]

Hi folks

As an owner of an Focusrite Scarlett 6i6 (gen 1)i was bothered that i 
could not

switch rear inputs 3/4 gain. After investigating the code i found the 
specs of

that interface not used right. I wrote a patch and tested this well so far.

Afaik the same could be used also for the 18i18 and 18i20, but i left 
those untouched

for i could not test myself. Pls review and take over in case its accepted.


Cheers ... Jens

The patch:

--- /sound/usb/mixer_scarlett_nv.c    2017-04-08 09:53:53.000000000 +0200
+++ /sound/usb/mixer_scarlett.c    2017-08-26 03:15:15.734930629 +0200
@@ -152,6 +152,7 @@
      SCARLETT_OUTPUTS,
      SCARLETT_SWITCH_IMPEDANCE,
      SCARLETT_SWITCH_PAD,
+    SCARLETT_SWITCH_GAIN,
  };

  enum {
@@ -202,6 +203,15 @@
      }
  };

+static const struct scarlett_mixer_elem_enum_info opt_gain = {
+    .start = 0,
+    .len = 2,
+    .offsets = {},
+    .names = (char const * const []){
+        "Lo", "Hi"
+    }
+};
+
  static const struct scarlett_mixer_elem_enum_info opt_impedance = {
      .start = 0,
      .len = 2,
@@ -664,8 +674,8 @@
          { .num = 1, .type = SCARLETT_SWITCH_PAD, .name = NULL},
          { .num = 2, .type = SCARLETT_SWITCH_IMPEDANCE, .name = NULL},
          { .num = 2, .type = SCARLETT_SWITCH_PAD, .name = NULL},
-        { .num = 3, .type = SCARLETT_SWITCH_PAD, .name = NULL},
-        { .num = 4, .type = SCARLETT_SWITCH_PAD, .name = NULL},
+        { .num = 3, .type = SCARLETT_SWITCH_GAIN, .name = NULL},
+        { .num = 4, .type = SCARLETT_SWITCH_GAIN, .name = NULL},
      },

      .matrix_mux_init = {
@@ -895,6 +905,15 @@
              if (err < 0)
                  return err;
              break;
+        case SCARLETT_SWITCH_GAIN:
+            sprintf(mx, "Input %d Gain Switch", ctl->num);
+            err = add_new_ctl(mixer, &usb_scarlett_ctl_enum,
+                      scarlett_ctl_enum_resume, 0x01,
+                      0x08, ctl->num, USB_MIXER_S16, 1, mx,
+                      &opt_gain, &elem);
+            if (err < 0)
+                return err;
+            break;
          }
      }


-- 

Jens Verwiebe
Allerskehre 44 - 22309 Hamburg

Tel.: +49 40 68 78 50
mobile: +49 172 400 49 07
mailto: info at jensverwiebe.de
web: http://www.jensverwiebe.de