ALSA: usbmixer - introduce /proc/asound/card#/usbmixer file

The usbmixer proc file contains mapping between ALSA control API and
USB mixer control units. The purpose of this file is for debugging
and a problem diagnostics.

Signed-off-by: Jaroslav Kysela <perex@perex.cz>

diff --git a/sound/usb/usbmixer.c b/sound/usb/usbmixer.c
index dd0c1d7..170bfd4 100644 (file)
--- a/sound/usb/usbmixer.c
+++ b/sound/usb/usbmixer.c
@@ -69,13 +69,16 @@ static const struct rc_config {
        { USB_ID(0x041e, 0x3048), 2, 2, 6, 6,  2,  0x6e91 }, /* Toshiba SB0500 */
 };
 
+#define MAX_ID_ELEMS   256
+
 struct usb_mixer_interface {
        struct snd_usb_audio *chip;
        unsigned int ctrlif;
        struct list_head list;
        unsigned int ignore_ctl_error;
        struct urb *urb;
-       struct usb_mixer_elem_info **id_elems; /* array[256], indexed by unit id */
+       /* array[MAX_ID_ELEMS], indexed by unit id */
+       struct usb_mixer_elem_info **id_elems;
 
        /* Sound Blaster remote control stuff */
        const struct rc_config *rc_cfg;
@@ -1825,6 +1828,45 @@ static void snd_usb_mixer_notify_id(struct usb_mixer_interface *mixer,
                               info->elem_id);
 }
 
+static void snd_usb_mixer_dump_cval(struct snd_info_buffer *buffer,
+                                   int unitid,
+                                   struct usb_mixer_elem_info *cval)
+{
+       static char *val_types[] = {"BOOLEAN", "INV_BOOLEAN",
+                                   "S8", "U8", "S16", "U16"};
+       snd_iprintf(buffer, "  Unit: %i\n", unitid);
+       if (cval->elem_id)
+               snd_iprintf(buffer, "    Control: name=\"%s\", index=%i\n",
+                               cval->elem_id->name, cval->elem_id->index);
+       snd_iprintf(buffer, "    Info: id=%i, control=%i, cmask=0x%x, "
+                           "channels=%i, type=\"%s\"\n", cval->id,
+                           cval->control, cval->cmask, cval->channels,
+                           val_types[cval->val_type]);
+       snd_iprintf(buffer, "    Volume: min=%i, max=%i, dBmin=%i, dBmax=%i\n",
+                           cval->min, cval->max, cval->dBmin, cval->dBmax);
+}
+
+static void snd_usb_mixer_proc_read(struct snd_info_entry *entry,
+                                   struct snd_info_buffer *buffer)
+{
+       struct snd_usb_audio *chip = entry->private_data;
+       struct usb_mixer_interface *mixer;
+       struct usb_mixer_elem_info *cval;
+       int unitid;
+
+       list_for_each_entry(mixer, &chip->mixer_list, list) {
+               snd_iprintf(buffer,
+                       "USB Mixer: ctrlif=%i, ctlerr=%i\n",
+                               mixer->ctrlif, mixer->ignore_ctl_error);
+               snd_iprintf(buffer, "Card: %s\n", chip->card->longname);
+               for (unitid = 0; unitid < MAX_ID_ELEMS; unitid++) {
+                       for (cval = mixer->id_elems[unitid]; cval;
+                                               cval = cval->next_id_elem)
+                               snd_usb_mixer_dump_cval(buffer, unitid, cval);
+               }
+       }
+}
+
 static void snd_usb_mixer_memory_change(struct usb_mixer_interface *mixer,
                                        int unitid)
 {
@@ -2187,20 +2229,21 @@ static int snd_xonar_u1_controls_create(struct usb_mixer_interface *mixer)
 }
 
 void snd_emuusb_set_samplerate(struct snd_usb_audio *chip,
-               unsigned char samplerate_id)
+                              unsigned char samplerate_id)
 {
-        struct usb_mixer_interface *mixer;
-        struct usb_mixer_elem_info *cval;
-        int unitid = 12; /* SamleRate ExtensionUnit ID */
+       struct usb_mixer_interface *mixer;
+       struct usb_mixer_elem_info *cval;
+       int unitid = 12; /* SamleRate ExtensionUnit ID */
 
-        list_for_each_entry(mixer, &chip->mixer_list, list) {
-                cval = mixer->id_elems[unitid];
-                if (cval) {
-                       set_cur_ctl_value(cval, cval->control << 8, samplerate_id);
+       list_for_each_entry(mixer, &chip->mixer_list, list) {
+               cval = mixer->id_elems[unitid];
+               if (cval) {
+                       set_cur_ctl_value(cval, cval->control << 8,
+                                         samplerate_id);
                        snd_usb_mixer_notify_id(mixer, unitid);
-                }
-                break;
-        }
+               }
+               break;
+       }
 }
 
 int snd_usb_create_mixer(struct snd_usb_audio *chip, int ctrlif,
@@ -2210,6 +2253,7 @@ int snd_usb_create_mixer(struct snd_usb_audio *chip, int ctrlif,
                .dev_free = snd_usb_mixer_dev_free
        };
        struct usb_mixer_interface *mixer;
+       struct snd_info_entry *entry;
        int err;
 
        strcpy(chip->card->mixername, "USB Mixer");
@@ -2236,8 +2280,6 @@ int snd_usb_create_mixer(struct snd_usb_audio *chip, int ctrlif,
        if (mixer->chip->usb_id == USB_ID(0x041e, 0x3020) ||
            mixer->chip->usb_id == USB_ID(0x041e, 0x3040) ||
            mixer->chip->usb_id == USB_ID(0x041e, 0x3048)) {
-               struct snd_info_entry *entry;
-
                if ((err = snd_audigy2nx_controls_create(mixer)) < 0)
                        goto _error;
                if (!snd_card_proc_new(chip->card, "audigy2nx", &entry))
@@ -2255,6 +2297,11 @@ int snd_usb_create_mixer(struct snd_usb_audio *chip, int ctrlif,
        err = snd_device_new(chip->card, SNDRV_DEV_LOWLEVEL, mixer, &dev_ops);
        if (err < 0)
                goto _error;
+
+       if (list_empty(&chip->mixer_list) &&
+           !snd_card_proc_new(chip->card, "usbmixer", &entry))
+               snd_info_set_text_ops(entry, chip, snd_usb_mixer_proc_read);
+
        list_add(&mixer->list, &chip->mixer_list);
        return 0;