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USB: gadget: Drop NULL test on list_entry result

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list_entry, which is an alias for container_of, cannot return NULL, as
there is no way to add a NULL value to a doubly linked list.

A simplified version of the semantic match that findds this problem is as
follows:
(http://www.emn.fr/x-info/coccinelle/)

// <smpl>
@r@
expression x,E;
statement S1,S2;
position p,p1;
@@

*x = list_entry@p(...)
... when != x = E
*if@p1 (x == NULL) S1 else S2
// </smpl>

Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This commit is contained in:
Julia Lawall 2009-07-12 09:43:52 +02:00 committed by Greg Kroah-Hartman
parent d12b85e7de
commit 058e698b63
1 changed files with 25 additions and 31 deletions
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56
drivers/usb/gadget/amd5536udc.c
View file

@ -2378,40 +2378,34 @@ static irqreturn_t udc_data_in_isr(struct udc *dev, int ep_ix)
if (!ep->cancel_transfer && !list_empty(&ep->queue)) {
req = list_entry(ep->queue.next,
struct udc_request, queue);
if (req) {
/*
* length bytes transfered
* check dma done of last desc. in PPBDU mode
*/
if (use_dma_ppb_du) {
td = udc_get_last_dma_desc(req);
if (td) {
dma_done =
AMD_GETBITS(td->status,
UDC_DMA_IN_STS_BS);
/* don't care DMA done */
req->req.actual =
req->req.length;
}
} else {
/* assume all bytes transferred */
/*
* length bytes transfered
* check dma done of last desc. in PPBDU mode
*/
if (use_dma_ppb_du) {
td = udc_get_last_dma_desc(req);
if (td) {
dma_done =
AMD_GETBITS(td->status,
UDC_DMA_IN_STS_BS);
/* don't care DMA done */
req->req.actual = req->req.length;
}
} else {
/* assume all bytes transferred */
req->req.actual = req->req.length;
}
if (req->req.actual == req->req.length) {
/* complete req */
complete_req(ep, req, 0);
req->dma_going = 0;
/* further request available ? */
if (list_empty(&ep->queue)) {
/* disable interrupt */
tmp = readl(
&dev->regs->ep_irqmsk);
tmp |= AMD_BIT(ep->num);
writel(tmp,
&dev->regs->ep_irqmsk);
}
if (req->req.actual == req->req.length) {
/* complete req */
complete_req(ep, req, 0);
req->dma_going = 0;
/* further request available ? */
if (list_empty(&ep->queue)) {
/* disable interrupt */
tmp = readl(&dev->regs->ep_irqmsk);
tmp |= AMD_BIT(ep->num);
writel(tmp, &dev->regs->ep_irqmsk);
}
}
}