diff options
author | Bjørn Mork <bjorn@mork.no> | 2012-01-16 15:12:00 +0100 |
---|---|---|
committer | Bjørn Mork <bjorn@mork.no> | 2012-06-04 21:58:02 +0200 |
commit | 042336604b659ef52718368d896b76d872ab4407 (patch) | |
tree | 3790db0b241a739ac262d37eba4f9d58b64cd0d1 | |
parent | cca0eb67082c4cfda9a7e8cc4ef9ca5cd249cc37 (diff) |
USB: cdc-wdm: no need to use usb_alloc_coherent
As Documentation/usb/dma.txt states:
Most drivers should *NOT* be using these primitives; they don't need
to use this type of memory (dma-coherent), and memory returned from
kmalloc() will work just fine.
This driver handle only very low bandwith transfers. It is not an
obvious candidate for usb_alloc_coherent().
Using these calls only serves to complicate the code for no gain,
as has been shown by multiple bugs related to this allocation path.
Signed-off-by: Bjørn Mork <bjorn@mork.no>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
(cherry picked from commit 8457d99cab81e91724b43363f7fccd851d766187)
Signed-off-by: Bjørn Mork <bjorn@mork.no>
-rw-r--r-- | drivers/usb/class/cdc-wdm.c | 39 |
1 files changed, 9 insertions, 30 deletions
diff --git a/drivers/usb/class/cdc-wdm.c b/drivers/usb/class/cdc-wdm.c index f1020f33a5a..d0ad0018398 100644 --- a/drivers/usb/class/cdc-wdm.c +++ b/drivers/usb/class/cdc-wdm.c @@ -276,14 +276,8 @@ static void free_urbs(struct wdm_device *desc) static void cleanup(struct wdm_device *desc) { - usb_free_coherent(interface_to_usbdev(desc->intf), - desc->wMaxPacketSize, - desc->sbuf, - desc->validity->transfer_dma); - usb_free_coherent(interface_to_usbdev(desc->intf), - desc->bMaxPacketSize0, - desc->inbuf, - desc->response->transfer_dma); + kfree(desc->sbuf); + kfree(desc->inbuf); kfree(desc->orq); kfree(desc->irq); kfree(desc->ubuf); @@ -727,19 +721,13 @@ next_desc: if (!desc->ubuf) goto err; - desc->sbuf = usb_alloc_coherent(interface_to_usbdev(intf), - desc->wMaxPacketSize, - GFP_KERNEL, - &desc->validity->transfer_dma); + desc->sbuf = kmalloc(desc->wMaxPacketSize, GFP_KERNEL); if (!desc->sbuf) goto err; - desc->inbuf = usb_alloc_coherent(interface_to_usbdev(intf), - desc->wMaxCommand, - GFP_KERNEL, - &desc->response->transfer_dma); + desc->inbuf = kmalloc(desc->wMaxCommand, GFP_KERNEL); if (!desc->inbuf) - goto err2; + goto err; usb_fill_int_urb( desc->validity, @@ -751,7 +739,6 @@ next_desc: desc, ep->bInterval ); - desc->validity->transfer_flags |= URB_NO_TRANSFER_DMA_MAP; desc->irq->bRequestType = (USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE); desc->irq->bRequest = USB_CDC_GET_ENCAPSULATED_RESPONSE; @@ -770,29 +757,21 @@ next_desc: wdm_in_callback, desc ); - desc->response->transfer_flags |= URB_NO_TRANSFER_DMA_MAP; usb_set_intfdata(intf, desc); rv = usb_register_dev(intf, &wdm_class); if (rv < 0) - goto err3; + goto err2; else dev_info(&intf->dev, "%s: USB WDM device\n", dev_name(intf->usb_dev)); out: return rv; -err3: - usb_set_intfdata(intf, NULL); - usb_free_coherent(interface_to_usbdev(desc->intf), - desc->bMaxPacketSize0, - desc->inbuf, - desc->response->transfer_dma); err2: - usb_free_coherent(interface_to_usbdev(desc->intf), - desc->wMaxPacketSize, - desc->sbuf, - desc->validity->transfer_dma); + usb_set_intfdata(intf, NULL); err: free_urbs(desc); + kfree(desc->inbuf); + kfree(desc->sbuf); kfree(desc->ubuf); kfree(desc->orq); kfree(desc->irq); |