From: Bjørn Mork Date: Mon, 16 Jan 2012 14:12:00 +0000 (+0100) Subject: USB: cdc-wdm: no need to use usb_alloc_coherent X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=8457d99cab81e91724b43363f7fccd851d766187;p=GitHub%2Fexynos8895%2Fandroid_kernel_samsung_universal8895.git 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 Signed-off-by: Greg Kroah-Hartman --- diff --git a/drivers/usb/class/cdc-wdm.c b/drivers/usb/class/cdc-wdm.c index 846dfa603447..8909058b1bb1 100644 --- a/drivers/usb/class/cdc-wdm.c +++ b/drivers/usb/class/cdc-wdm.c @@ -256,14 +256,8 @@ 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); @@ -688,19 +682,13 @@ 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, @@ -712,7 +700,6 @@ 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; @@ -731,30 +718,22 @@ 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, "cdc-wdm%d: USB WDM device\n", intf->minor - WDM_MINOR_BASE); 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);