ALSA: us122l: Drop mmap_count field

us122l.mmap_count field was used for counting the hwdep mmap opens and
syncing at disconnection.  But such a manual sync isn't needed, as the
refcount check is done in the ALSA core side.  So let's drop it.

Signed-off-by: Takashi Iwai <[email protected]>
Link: https://patch.msgid.link/[email protected]

Author: tiwai

sound/usb/usx2y/us122l.c

@@ -89,13 +89,6 @@ static void pt_info_set(struct usb_device *dev, u8 v)
 			     v, 0, NULL, 0, 1000, GFP_NOIO);
 }
 
-static void usb_stream_hwdep_vm_open(struct vm_area_struct *area)
-{
-	struct us122l *us122l = area->vm_private_data;
-
-	atomic_inc(&us122l->mmap_count);
-}
-
 static vm_fault_t usb_stream_hwdep_vm_fault(struct vm_fault *vmf)
 {
 	unsigned long offset;
@@ -132,17 +125,9 @@ static vm_fault_t usb_stream_hwdep_vm_fault(struct vm_fault *vmf)
 	return VM_FAULT_SIGBUS;
 }
 
-static void usb_stream_hwdep_vm_close(struct vm_area_struct *area)
-{
-	struct us122l *us122l = area->vm_private_data;
-
-	atomic_dec(&us122l->mmap_count);
-}
 
 static const struct vm_operations_struct usb_stream_hwdep_vm_ops = {
-	.open = usb_stream_hwdep_vm_open,
 	.fault = usb_stream_hwdep_vm_fault,
-	.close = usb_stream_hwdep_vm_close,
 };
 
 static int usb_stream_hwdep_open(struct snd_hwdep *hw, struct file *file)
@@ -218,7 +203,6 @@ static int usb_stream_hwdep_mmap(struct snd_hwdep *hw,
 	if (!read)
 		vm_flags_set(area, VM_DONTEXPAND);
 	area->vm_private_data = us122l;
-	atomic_inc(&us122l->mmap_count);
 out:
 	mutex_unlock(&us122l->mutex);
 	return err;

sound/usb/usx2y/us122l.h

@@ -16,8 +16,6 @@ struct us122l {
 	struct file		*slave;
 	struct list_head	midi_list;
 
-	atomic_t		mmap_count;
-
 	bool			is_us144;
 };