ALSA: usb-audio: Resume mixer values properly

Implement reset_resume callback so that the mixer values are properly
restored.  Still no boot quirks are called, so it might not work well
on some devices.

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

3 files changed, 99 insertions, 25 deletions

diff --git a/sound/usb/card.c b/sound/usb/card.c
index d979050e6a6a..025224136129 100644
--- a/sound/usb/card.c
+++ b/sound/usb/card.c
@@ -691,12 +691,12 @@ static int usb_audio_suspend(struct usb_interface *intf, pm_message_t message)
         }
 
         list_for_each_entry(mixer, &chip->mixer_list, list)
-                snd_usb_mixer_inactivate(mixer);
+                snd_usb_mixer_suspend(mixer);
 
         return 0;
 }
 
-static int usb_audio_resume(struct usb_interface *intf)
+static int __usb_audio_resume(struct usb_interface *intf, bool reset_resume)
 {
         struct snd_usb_audio *chip = usb_get_intfdata(intf);
         struct usb_mixer_interface *mixer;
@@ -711,7 +711,7 @@ static int usb_audio_resume(struct usb_interface *intf)
          * we just notify and restart the mixers
          */
         list_for_each_entry(mixer, &chip->mixer_list, list) {
-                err = snd_usb_mixer_activate(mixer);
+                err = snd_usb_mixer_resume(mixer, reset_resume);
                 if (err < 0)
                         goto err_out;
         }
@@ -723,9 +723,20 @@ static int usb_audio_resume(struct usb_interface *intf)
 err_out:
         return err;
 }
+
+static int usb_audio_resume(struct usb_interface *intf)
+{
+        return __usb_audio_resume(intf, false);
+}
+
+static int usb_audio_reset_resume(struct usb_interface *intf)
+{
+        return __usb_audio_resume(intf, true);
+}
 #else
 #define usb_audio_suspend       NULL
 #define usb_audio_resume        NULL
+#define usb_audio_reset_resume  NULL
 #endif          /* CONFIG_PM */
 
 static struct usb_device_id usb_audio_ids [] = {
@@ -747,6 +758,7 @@ static struct usb_driver usb_audio_driver = {
         .disconnect =   usb_audio_disconnect,
         .suspend =      usb_audio_suspend,
         .resume =       usb_audio_resume,
+        .reset_resume = usb_audio_reset_resume,
         .id_table =     usb_audio_ids,
         .supports_autosuspend = 1,
 };
diff --git a/sound/usb/mixer.c b/sound/usb/mixer.c
index 44b0ba4feab3..aa9bc19aae68 100644
--- a/sound/usb/mixer.c
+++ b/sound/usb/mixer.c
@@ -2299,26 +2299,6 @@ requeue:
         }
 }
 
-/* stop any bus activity of a mixer */
-void snd_usb_mixer_inactivate(struct usb_mixer_interface *mixer)
-{
-        usb_kill_urb(mixer->urb);
-        usb_kill_urb(mixer->rc_urb);
-}
-
-int snd_usb_mixer_activate(struct usb_mixer_interface *mixer)
-{
-        int err;
-
-        if (mixer->urb) {
-                err = usb_submit_urb(mixer->urb, GFP_NOIO);
-                if (err < 0)
-                        return err;
-        }
-
-        return 0;
-}
-
 /* create the handler for the optional status interrupt endpoint */
 static int snd_usb_mixer_status_create(struct usb_mixer_interface *mixer)
 {
@@ -2417,3 +2397,82 @@ void snd_usb_mixer_disconnect(struct list_head *p)
         usb_kill_urb(mixer->urb);
         usb_kill_urb(mixer->rc_urb);
 }
+
+#ifdef CONFIG_PM
+/* stop any bus activity of a mixer */
+static void snd_usb_mixer_inactivate(struct usb_mixer_interface *mixer)
+{
+        usb_kill_urb(mixer->urb);
+        usb_kill_urb(mixer->rc_urb);
+}
+
+static int snd_usb_mixer_activate(struct usb_mixer_interface *mixer)
+{
+        int err;
+
+        if (mixer->urb) {
+                err = usb_submit_urb(mixer->urb, GFP_NOIO);
+                if (err < 0)
+                        return err;
+        }
+
+        return 0;
+}
+
+int snd_usb_mixer_suspend(struct usb_mixer_interface *mixer)
+{
+        snd_usb_mixer_inactivate(mixer);
+        return 0;
+}
+
+static int restore_mixer_value(struct usb_mixer_elem_info *cval)
+{
+        int c, err, idx;
+
+        if (cval->cmask) {
+                idx = 0;
+                for (c = 0; c < MAX_CHANNELS; c++) {
+                        if (!(cval->cmask & (1 << c)))
+                                continue;
+                        if (cval->cached & (1 << c)) {
+                                err = set_cur_mix_value(cval, c + 1, idx,
+                                                        cval->cache_val[idx]);
+                                if (err < 0)
+                                        return err;
+                        }
+                        idx++;
+                }
+        } else {
+                /* master */
+                if (cval->cached) {
+                        err = set_cur_mix_value(cval, 0, 0, *cval->cache_val);
+                        if (err < 0)
+                                return err;
+                }
+        }
+
+        return 0;
+}
+
+int snd_usb_mixer_resume(struct usb_mixer_interface *mixer, bool reset_resume)
+{
+        struct usb_mixer_elem_info *cval;
+        int id, err;
+
+        /* FIXME: any mixer quirks? */
+
+        if (reset_resume) {
+                /* restore cached mixer values */
+                for (id = 0; id < MAX_ID_ELEMS; id++) {
+                        for (cval = mixer->id_elems[id]; cval;
+                             cval = cval->next_id_elem) {
+                                err = restore_mixer_value(cval);
+                                if (err < 0)
+                                        return err;
+                        }
+                }
+        }
+
+        return snd_usb_mixer_activate(mixer);
+}
+#endif
diff --git a/sound/usb/mixer.h b/sound/usb/mixer.h
index aab80df201bd..73b1f649447b 100644
--- a/sound/usb/mixer.h
+++ b/sound/usb/mixer.h
@@ -63,8 +63,6 @@ void snd_usb_mixer_notify_id(struct usb_mixer_interface *mixer, int unitid);
 
 int snd_usb_mixer_set_ctl_value(struct usb_mixer_elem_info *cval,
                                 int request, int validx, int value_set);
-void snd_usb_mixer_inactivate(struct usb_mixer_interface *mixer);
-int snd_usb_mixer_activate(struct usb_mixer_interface *mixer);
 
 int snd_usb_mixer_add_control(struct usb_mixer_interface *mixer,
                               struct snd_kcontrol *kctl);
@@ -72,4 +70,9 @@ int snd_usb_mixer_add_control(struct usb_mixer_interface *mixer,
 int snd_usb_mixer_vol_tlv(struct snd_kcontrol *kcontrol, int op_flag,
                           unsigned int size, unsigned int __user *_tlv);
 
+#ifdef CONFIG_PM
+int snd_usb_mixer_suspend(struct usb_mixer_interface *mixer);
+int snd_usb_mixer_resume(struct usb_mixer_interface *mixer, bool reset_resume);
+#endif
+
 #endif /* __USBMIXER_H */