[media] pwc: properly allocate dma-able memory for ISO buffers

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

2 files changed, 28 insertions, 59 deletions

diff --git a/drivers/media/video/pwc/pwc-if.c b/drivers/media/video/pwc/pwc-if.c
index a6b5fde5c3ad..4c1c056ffdf4 100644
--- a/drivers/media/video/pwc/pwc-if.c
+++ b/drivers/media/video/pwc/pwc-if.c
@@ -376,7 +376,6 @@ static int pwc_isoc_init(struct pwc_device *pdev)
         int i, j, ret;
         struct usb_interface *intf;
         struct usb_host_interface *idesc = NULL;
-        void *kbuf;
 
         if (pdev->iso_init)
                 return 0;
@@ -416,20 +415,7 @@ static int pwc_isoc_init(struct pwc_device *pdev)
         if (ret < 0)
                 return ret;
 
-        /* Allocate Isochronuous pipe buffers */
-        for (i = 0; i < MAX_ISO_BUFS; i++) {
-                kbuf = kzalloc(ISO_BUFFER_SIZE, GFP_KERNEL);
-                if (kbuf == NULL) {
-                        PWC_ERROR("Failed to allocate iso buffer %d.\n", i);
-                        pdev->iso_init = 1;
-                        pwc_isoc_cleanup(pdev);
-                        return -ENOMEM;
-                }
-                PWC_DEBUG_MEMORY("Allocated iso buffer at %p.\n", kbuf);
-                pdev->sbuf[i].data = kbuf;
-        }
-
-        /* Allocate Isochronuous urbs */
+        /* Allocate and init Isochronuous urbs */
         for (i = 0; i < MAX_ISO_BUFS; i++) {
                 urb = usb_alloc_urb(ISO_FRAMES_PER_DESC, GFP_KERNEL);
                 if (urb == NULL) {
@@ -438,19 +424,23 @@ static int pwc_isoc_init(struct pwc_device *pdev)
                         pwc_isoc_cleanup(pdev);
                         return -ENOMEM;
                 }
-                pdev->sbuf[i].urb = urb;
+                pdev->urbs[i] = urb;
                 PWC_DEBUG_MEMORY("Allocated URB at 0x%p\n", urb);
-        }
-
-        /* init URB structure */
-        for (i = 0; i < MAX_ISO_BUFS; i++) {
-                urb = pdev->sbuf[i].urb;
 
                 urb->interval = 1; // devik
                 urb->dev = udev;
                 urb->pipe = usb_rcvisocpipe(udev, pdev->vendpoint);
-                urb->transfer_flags = URB_ISO_ASAP;
-                urb->transfer_buffer = pdev->sbuf[i].data;
+                urb->transfer_flags = URB_ISO_ASAP | URB_NO_TRANSFER_DMA_MAP;
+                urb->transfer_buffer = usb_alloc_coherent(udev,
+                                                          ISO_BUFFER_SIZE,
+                                                          GFP_KERNEL,
+                                                          &urb->transfer_dma);
+                if (urb->transfer_buffer == NULL) {
+                        PWC_ERROR("Failed to allocate urb buffer %d\n", i);
+                        pdev->iso_init = 1;
+                        pwc_isoc_cleanup(pdev);
+                        return -ENOMEM;
+                }
                 urb->transfer_buffer_length = ISO_BUFFER_SIZE;
                 urb->complete = pwc_isoc_handler;
                 urb->context = pdev;
@@ -464,14 +454,14 @@ static int pwc_isoc_init(struct pwc_device *pdev)
 
         /* link */
         for (i = 0; i < MAX_ISO_BUFS; i++) {
-                ret = usb_submit_urb(pdev->sbuf[i].urb, GFP_KERNEL);
+                ret = usb_submit_urb(pdev->urbs[i], GFP_KERNEL);
                 if (ret) {
                         PWC_ERROR("isoc_init() submit_urb %d failed with error %d\n", i, ret);
                         pdev->iso_init = 1;
                         pwc_isoc_cleanup(pdev);
                         return ret;
                 }
-                PWC_DEBUG_MEMORY("URB 0x%p submitted.\n", pdev->sbuf[i].urb);
+                PWC_DEBUG_MEMORY("URB 0x%p submitted.\n", pdev->urbs[i]);
         }
 
         /* All is done... */
@@ -486,12 +476,9 @@ static void pwc_iso_stop(struct pwc_device *pdev)
 
         /* Unlinking ISOC buffers one by one */
         for (i = 0; i < MAX_ISO_BUFS; i++) {
-                struct urb *urb;
-
-                urb = pdev->sbuf[i].urb;
-                if (urb) {
-                        PWC_DEBUG_MEMORY("Unlinking URB %p\n", urb);
-                        usb_kill_urb(urb);
+                if (pdev->urbs[i]) {
+                        PWC_DEBUG_MEMORY("Unlinking URB %p\n", pdev->urbs[i]);
+                        usb_kill_urb(pdev->urbs[i]);
                 }
         }
 }
@@ -502,21 +489,22 @@ static void pwc_iso_free(struct pwc_device *pdev)
 
         /* Freeing ISOC buffers one by one */
         for (i = 0; i < MAX_ISO_BUFS; i++) {
-                struct urb *urb;
-
-                urb = pdev->sbuf[i].urb;
-                if (urb) {
+                if (pdev->urbs[i]) {
                         PWC_DEBUG_MEMORY("Freeing URB\n");
-                        usb_free_urb(urb);
-                        pdev->sbuf[i].urb = NULL;
+                        if (pdev->urbs[i]->transfer_buffer) {
+                                usb_free_coherent(pdev->udev,
+                                        pdev->urbs[i]->transfer_buffer_length,
+                                        pdev->urbs[i]->transfer_buffer,
+                                        pdev->urbs[i]->transfer_dma);
+                        }
+                        usb_free_urb(pdev->urbs[i]);
+                        pdev->urbs[i] = NULL;
                 }
         }
 }
 
 static void pwc_isoc_cleanup(struct pwc_device *pdev)
 {
-        int i;
-
         PWC_DEBUG_OPEN(">> pwc_isoc_cleanup()\n");
 
         if (pdev->iso_init == 0)
@@ -526,16 +514,6 @@ static void pwc_isoc_cleanup(struct pwc_device *pdev)
         pwc_iso_free(pdev);
         usb_set_interface(pdev->udev, 0, 0);
 
-        /* Release Iso-pipe buffers */
-        for (i = 0; i < MAX_ISO_BUFS; i++) {
-                if (pdev->sbuf[i].data != NULL) {
-                        PWC_DEBUG_MEMORY("Freeing ISO buffer at %p.\n",
-                                         pdev->sbuf[i].data);
-                        kfree(pdev->sbuf[i].data);
-                        pdev->sbuf[i].data = NULL;
-                }
-        }
-
         pdev->iso_init = 0;
         PWC_DEBUG_OPEN("<< pwc_isoc_cleanup()\n");
 }
diff --git a/drivers/media/video/pwc/pwc.h b/drivers/media/video/pwc/pwc.h
index d65cd14ef9f2..1cfb8b475a3f 100644
--- a/drivers/media/video/pwc/pwc.h
+++ b/drivers/media/video/pwc/pwc.h
@@ -128,15 +128,6 @@
 #define DEVICE_USE_CODEC3(x) ((x)>=700)
 #define DEVICE_USE_CODEC23(x) ((x)>=675)
 
-/* The following structures were based on cpia.h. Why reinvent the wheel? :-) */
-struct pwc_iso_buf
-{
-        void *data;
-        int  length;
-        int  read;
-        struct urb *urb;
-};
-
 /* intermediate buffers with raw data from the USB cam */
 struct pwc_frame_buf
 {
@@ -180,7 +171,7 @@ struct pwc_device
         int cmd_len;
         unsigned char cmd_buf[13];
 
-        struct pwc_iso_buf sbuf[MAX_ISO_BUFS];
+        struct urb *urbs[MAX_ISO_BUFS];
         char iso_init;
 
         /* videobuf2 queue and queued buffers list */