[media] em28xx: use usb_alloc_coherent() for audio

Instead of allocating transfer buffers with kmalloc() use
usb_alloc_coherent().

This patch should make it work also with ARM CPUs.

Reviewed-by: Frank Schäfer <fschaefer.oss@googlemail.com>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>

1 files changed, 20 insertions, 11 deletions

diff --git a/drivers/media/usb/em28xx/em28xx-audio.c b/drivers/media/usb/em28xx/em28xx-audio.c
index a6eef06ffdcd..e5120430ec80 100644
--- a/drivers/media/usb/em28xx/em28xx-audio.c
+++ b/drivers/media/usb/em28xx/em28xx-audio.c
@@ -64,16 +64,22 @@ static int em28xx_deinit_isoc_audio(struct em28xx *dev)
 
         dprintk("Stopping isoc\n");
         for (i = 0; i < EM28XX_AUDIO_BUFS; i++) {
+                struct urb *urb = dev->adev.urb[i];
+
                 if (!irqs_disabled())
-                        usb_kill_urb(dev->adev.urb[i]);
+                        usb_kill_urb(urb);
                 else
-                        usb_unlink_urb(dev->adev.urb[i]);
+                        usb_unlink_urb(urb);
 
-                usb_free_urb(dev->adev.urb[i]);
-                dev->adev.urb[i] = NULL;
+                usb_free_coherent(dev->udev,
+                                  urb->transfer_buffer_length,
+                                  dev->adev.transfer_buffer[i],
+                                  urb->transfer_dma);
 
-                kfree(dev->adev.transfer_buffer[i]);
                 dev->adev.transfer_buffer[i] = NULL;
+
+                usb_free_urb(urb);
+                dev->adev.urb[i] = NULL;
         }
 
         return 0;
@@ -176,12 +182,8 @@ static int em28xx_init_audio_isoc(struct em28xx *dev)
         for (i = 0; i < EM28XX_AUDIO_BUFS; i++) {
                 struct urb *urb;
                 int j, k;
+                void *buf;
 
-                dev->adev.transfer_buffer[i] = kmalloc(sb_size, GFP_ATOMIC);
-                if (!dev->adev.transfer_buffer[i])
-                        return -ENOMEM;
-
-                memset(dev->adev.transfer_buffer[i], 0x80, sb_size);
                 urb = usb_alloc_urb(EM28XX_NUM_AUDIO_PACKETS, GFP_ATOMIC);
                 if (!urb) {
                         em28xx_errdev("usb_alloc_urb failed!\n");
@@ -192,10 +194,17 @@ static int em28xx_init_audio_isoc(struct em28xx *dev)
                         return -ENOMEM;
                 }
 
+                buf = usb_alloc_coherent(dev->udev, sb_size, GFP_ATOMIC,
+                                         &urb->transfer_dma);
+                if (!buf)
+                        return -ENOMEM;
+                dev->adev.transfer_buffer[i] = buf;
+                memset(buf, 0x80, sb_size);
+
                 urb->dev = dev->udev;
                 urb->context = dev;
                 urb->pipe = usb_rcvisocpipe(dev->udev, EM28XX_EP_AUDIO);
-                urb->transfer_flags = URB_ISO_ASAP;
+                urb->transfer_flags = URB_ISO_ASAP | URB_NO_TRANSFER_DMA_MAP;
                 urb->transfer_buffer = dev->adev.transfer_buffer[i];
                 urb->interval = 1;
                 urb->complete = em28xx_audio_isocirq;