[ALSA] usb-audio: use usb_buffer_alloc/free

USB generic driver
Use the USB buffer allocation functions to avoid repeated DMA mappings
of our buffers, which are re-used quite a lot.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>

1 files changed, 13 insertions, 4 deletions

diff --git a/sound/usb/usbmidi.c b/sound/usb/usbmidi.c
index 5778a9b725ec..d0d895df5375 100644
--- a/sound/usb/usbmidi.c
+++ b/sound/usb/usbmidi.c
@@ -765,7 +765,10 @@ static snd_rawmidi_ops_t snd_usbmidi_input_ops = {
 static void snd_usbmidi_in_endpoint_delete(snd_usb_midi_in_endpoint_t* ep)
 {
         if (ep->urb) {
-                kfree(ep->urb->transfer_buffer);
+                usb_buffer_free(ep->umidi->chip->dev,
+                                ep->urb->transfer_buffer_length,
+                                ep->urb->transfer_buffer,
+                                ep->urb->transfer_dma);
                 usb_free_urb(ep->urb);
         }
         kfree(ep);
@@ -799,7 +802,8 @@ static int snd_usbmidi_in_endpoint_create(snd_usb_midi_t* umidi,
         else
                 pipe = usb_rcvbulkpipe(umidi->chip->dev, ep_info->in_ep);
         length = usb_maxpacket(umidi->chip->dev, pipe, 0);
-        buffer = kmalloc(length, GFP_KERNEL);
+        buffer = usb_buffer_alloc(umidi->chip->dev, length, GFP_KERNEL,
+                                  &ep->urb->transfer_dma);
         if (!buffer) {
                 snd_usbmidi_in_endpoint_delete(ep);
                 return -ENOMEM;
@@ -812,6 +816,7 @@ static int snd_usbmidi_in_endpoint_create(snd_usb_midi_t* umidi,
                 usb_fill_bulk_urb(ep->urb, umidi->chip->dev, pipe, buffer, length,
                                   snd_usb_complete_callback(snd_usbmidi_in_urb_complete),
                                   ep);
+        ep->urb->transfer_flags = URB_NO_TRANSFER_DMA_MAP;
 
         rep->in = ep;
         return 0;
@@ -835,7 +840,9 @@ static void snd_usbmidi_out_endpoint_delete(snd_usb_midi_out_endpoint_t* ep)
         if (ep->tasklet.func)
                 tasklet_kill(&ep->tasklet);
         if (ep->urb) {
-                kfree(ep->urb->transfer_buffer);
+                usb_buffer_free(ep->umidi->chip->dev, ep->max_transfer,
+                                ep->urb->transfer_buffer,
+                                ep->urb->transfer_dma);
                 usb_free_urb(ep->urb);
         }
         kfree(ep);
@@ -867,7 +874,8 @@ static int snd_usbmidi_out_endpoint_create(snd_usb_midi_t* umidi,
         /* we never use interrupt output pipes */
         pipe = usb_sndbulkpipe(umidi->chip->dev, ep_info->out_ep);
         ep->max_transfer = usb_maxpacket(umidi->chip->dev, pipe, 1);
-        buffer = kmalloc(ep->max_transfer, GFP_KERNEL);
+        buffer = usb_buffer_alloc(umidi->chip->dev, ep->max_transfer,
+                                  GFP_KERNEL, &ep->urb->transfer_dma);
         if (!buffer) {
                 snd_usbmidi_out_endpoint_delete(ep);
                 return -ENOMEM;
@@ -875,6 +883,7 @@ static int snd_usbmidi_out_endpoint_create(snd_usb_midi_t* umidi,
         usb_fill_bulk_urb(ep->urb, umidi->chip->dev, pipe, buffer,
                           ep->max_transfer,
                           snd_usb_complete_callback(snd_usbmidi_out_urb_complete), ep);
+        ep->urb->transfer_flags = URB_NO_TRANSFER_DMA_MAP;
 
         spin_lock_init(&ep->buffer_lock);
         tasklet_init(&ep->tasklet, snd_usbmidi_out_tasklet, (unsigned long)ep);