From c67ab134ba9f83f9de86e58adfeaa14a9efa6e00 Mon Sep 17 00:00:00 2001 From: David Brownell Date: Sun, 1 Jul 2007 12:21:00 -0700 Subject: usb gadget stack: remove usb_ep_*_buffer(), part 2 This patch removes controller driver infrastructure which supported the now-removed usb_ep_{alloc,free}_buffer() calls. As can be seen, many of the implementations of this were broken to various degrees. Many didn't properly return dma-coherent mappings; those which did so were necessarily ugly because of bogosity in the underlying dma_free_coherent() calls ... which on many platforms can't be called from the same contexts (notably in_irq) from which their dma_alloc_coherent() sibling can be called. The main potential downside of removing this is that gadget drivers wouldn't have specific knowledge that the controller drivers have: endpoints that aren't dma-capable don't need any dma mappings at all. Signed-off-by: David Brownell Signed-off-by: Greg Kroah-Hartman --- drivers/usb/gadget/net2280.c | 97 -------------------------------------------- 1 file changed, 97 deletions(-) (limited to 'drivers/usb/gadget/net2280.c') diff --git a/drivers/usb/gadget/net2280.c b/drivers/usb/gadget/net2280.c index 00fda334dc72..c3d364ecd4f8 100644 --- a/drivers/usb/gadget/net2280.c +++ b/drivers/usb/gadget/net2280.c @@ -450,100 +450,6 @@ net2280_free_request (struct usb_ep *_ep, struct usb_request *_req) /*-------------------------------------------------------------------------*/ -/* - * dma-coherent memory allocation (for dma-capable endpoints) - * - * NOTE: the dma_*_coherent() API calls suck. Most implementations are - * (a) page-oriented, so small buffers lose big; and (b) asymmetric with - * respect to calls with irqs disabled: alloc is safe, free is not. - * We currently work around (b), but not (a). - */ - -static void * -net2280_alloc_buffer ( - struct usb_ep *_ep, - unsigned bytes, - dma_addr_t *dma, - gfp_t gfp_flags -) -{ - void *retval; - struct net2280_ep *ep; - - ep = container_of (_ep, struct net2280_ep, ep); - if (!_ep) - return NULL; - *dma = DMA_ADDR_INVALID; - - if (ep->dma) - retval = dma_alloc_coherent(&ep->dev->pdev->dev, - bytes, dma, gfp_flags); - else - retval = kmalloc(bytes, gfp_flags); - return retval; -} - -static DEFINE_SPINLOCK(buflock); -static LIST_HEAD(buffers); - -struct free_record { - struct list_head list; - struct device *dev; - unsigned bytes; - dma_addr_t dma; -}; - -static void do_free(unsigned long ignored) -{ - spin_lock_irq(&buflock); - while (!list_empty(&buffers)) { - struct free_record *buf; - - buf = list_entry(buffers.next, struct free_record, list); - list_del(&buf->list); - spin_unlock_irq(&buflock); - - dma_free_coherent(buf->dev, buf->bytes, buf, buf->dma); - - spin_lock_irq(&buflock); - } - spin_unlock_irq(&buflock); -} - -static DECLARE_TASKLET(deferred_free, do_free, 0); - -static void -net2280_free_buffer ( - struct usb_ep *_ep, - void *address, - dma_addr_t dma, - unsigned bytes -) { - /* free memory into the right allocator */ - if (dma != DMA_ADDR_INVALID) { - struct net2280_ep *ep; - struct free_record *buf = address; - unsigned long flags; - - ep = container_of(_ep, struct net2280_ep, ep); - if (!_ep) - return; - - ep = container_of (_ep, struct net2280_ep, ep); - buf->dev = &ep->dev->pdev->dev; - buf->bytes = bytes; - buf->dma = dma; - - spin_lock_irqsave(&buflock, flags); - list_add_tail(&buf->list, &buffers); - tasklet_schedule(&deferred_free); - spin_unlock_irqrestore(&buflock, flags); - } else - kfree (address); -} - -/*-------------------------------------------------------------------------*/ - /* load a packet into the fifo we use for usb IN transfers. * works for all endpoints. * @@ -1392,9 +1298,6 @@ static const struct usb_ep_ops net2280_ep_ops = { .alloc_request = net2280_alloc_request, .free_request = net2280_free_request, - .alloc_buffer = net2280_alloc_buffer, - .free_buffer = net2280_free_buffer, - .queue = net2280_queue, .dequeue = net2280_dequeue, -- cgit v1.2.3-59-g8ed1b