[ALSA] Allow more than 2 channel modes [Linux 2.6.13]

This Linux kernel change "[ALSA] Allow more than 2 channel modes" is included in the Linux 2.6.13 release. This change is authored by Takashi Iwai <tiwai [at] suse.de> on Fri May 13 17:18:42 2005 +0200. The commit for this change in Linux stable tree is fd2c326 (patch).

[ALSA] Allow more than 2 channel modes

HDA Codec driver
Allow 'Channel Mode' control to have more than 2 modes.

Signed-off-by: Takashi Iwai <tiwai@suse.de>

There are 22 lines of Linux source code added/deleted in this change. Code changes to Linux kernel are as follows.

 sound/pci/hda/patch_realtek.c | 22 ++++++++++++++++------
 1 file changed, 16 insertions(+), 6 deletions(-)

diff --git a/sound/pci/hda/patch_realtek.c b/sound/pci/hda/patch_realtek.c
index 8a10482..9f12d1f 100644
--- a/sound/pci/hda/patch_realtek.c
+++ b/sound/pci/hda/patch_realtek.c
@@ -301,13 +301,14 @@ static int alc880_ch_mode_info(snd_kcontrol_t *kcontrol, snd_ctl_elem_info_t *ui
 {
    struct hda_codec *codec = snd_kcontrol_chip(kcontrol);
    struct alc_spec *spec = codec->spec;
+   int items = kcontrol->private_value ? (int)kcontrol->private_value : 2;

    snd_assert(spec->channel_mode, return -ENXIO);
    uinfo->type = SNDRV_CTL_ELEM_TYPE_ENUMERATED;
    uinfo->count = 1;
-   uinfo->value.enumerated.items = 2;
-   if (uinfo->value.enumerated.item >= 2)
-       uinfo->value.enumerated.item = 1;
+   uinfo->value.enumerated.items = items;
+   if (uinfo->value.enumerated.item >= items)
+       uinfo->value.enumerated.item = items - 1;
    sprintf(uinfo->value.enumerated.name, "%dch",
        spec->channel_mode[uinfo->value.enumerated.item].channels);
    return 0;
@@ -317,10 +318,16 @@ static int alc880_ch_mode_get(snd_kcontrol_t *kcontrol, snd_ctl_elem_value_t *uc
 {
    struct hda_codec *codec = snd_kcontrol_chip(kcontrol);
    struct alc_spec *spec = codec->spec;
+   int items = kcontrol->private_value ? (int)kcontrol->private_value : 2;
+   int i;

    snd_assert(spec->channel_mode, return -ENXIO);
-   ucontrol->value.enumerated.item[0] =
-       (spec->multiout.max_channels == spec->channel_mode[0].channels) ? 0 : 1;
+   for (i = 0; i < items; i++) {
+       if (spec->multiout.max_channels == spec->channel_mode[i].channels) {
+           ucontrol->value.enumerated.item[0] = i;
+           break;
+       }
+   }
    return 0;
 }

@@ -1036,9 +1043,11 @@ static void alc_free(struct hda_codec *codec)
    },
 };

-static struct alc_channel_mode alc880_test_modes[2] = {
+static struct alc_channel_mode alc880_test_modes[4] = {
    { 2, NULL },
+   { 4, NULL },
    { 6, NULL },
+   { 8, NULL },
 };

 static int alc_test_pin_ctl_info(snd_kcontrol_t *kcontrol, snd_ctl_elem_info_t *uinfo)
@@ -1211,6 +1220,7 @@ static int alc_test_pin_src_put(snd_kcontrol_t *kcontrol, snd_ctl_elem_value_t *
        .info = alc880_ch_mode_info,
        .get = alc880_ch_mode_get,
        .put = alc880_ch_mode_put,
+       .private_value = ARRAY_SIZE(alc880_test_modes),
    },
    { } /* end */
 };

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