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musb_host: simplify check for active URB

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The existance of the scheduling list shouldn't matter in
determining whether there's currectly an URB executing on a
hardware endpoint. What should actually matter is the 'in_qh'
or 'out_qh' fields of the 'struct musb_hw_ep' -- those are
set in musb_start_urb() and cleared in musb_giveback() when
the endpoint's URB list drains. Hence we should be able to
replace the big *switch* statements in musb_urb_dequeue()
and musb_h_disable() with mere musb_ep_get_qh() calls...

While at it, do some more changes:

 - add 'is_in' variable to musb_urb_dequeue();

 - remove the unnecessary 'epnum' variable from musb_h_disable();

 - fix the comment style in the vicinity.

This is a minor shrink of source and object code.

Signed-off-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This commit is contained in:
Sergei Shtylyov 2009-03-27 12:56:26 -07:00 committed by Greg Kroah-Hartman
parent 3e5c6dc711
commit 22a0d6f138
1 changed files with 14 additions and 58 deletions
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72
drivers/usb/musb/musb_host.c
View file

@ -2089,14 +2089,14 @@ static int musb_urb_dequeue(struct usb_hcd *hcd, struct urb *urb, int status)
{
struct musb *musb = hcd_to_musb(hcd);
struct musb_qh *qh;
struct list_head *sched;
unsigned long flags;
int is_in = usb_pipein(urb->pipe);
int ret;
DBG(4, "urb=%p, dev%d ep%d%s\n", urb,
usb_pipedevice(urb->pipe),
usb_pipeendpoint(urb->pipe),
usb_pipein(urb->pipe) ? "in" : "out");
is_in ? "in" : "out");
spin_lock_irqsave(&musb->lock, flags);
ret = usb_hcd_check_unlink_urb(hcd, urb, status);
@ -2107,45 +2107,23 @@ static int musb_urb_dequeue(struct usb_hcd *hcd, struct urb *urb, int status)
if (!qh)
goto done;
/* Any URB not actively programmed into endpoint hardware can be
/*
* Any URB not actively programmed into endpoint hardware can be
* immediately given back; that's any URB not at the head of an
* endpoint queue, unless someday we get real DMA queues. And even
* if it's at the head, it might not be known to the hardware...
*
* Otherwise abort current transfer, pending dma, etc.; urb->status
* Otherwise abort current transfer, pending DMA, etc.; urb->status
* has already been updated. This is a synchronous abort; it'd be
* OK to hold off until after some IRQ, though.
*
* NOTE: qh is invalid unless !list_empty(&hep->urb_list)
*/
if (!qh->is_ready || urb->urb_list.prev != &qh->hep->urb_list)
ret = -EINPROGRESS;
else {
switch (qh->type) {
case USB_ENDPOINT_XFER_CONTROL:
sched = &musb->control;
break;
case USB_ENDPOINT_XFER_BULK:
if (qh->mux == 1) {
if (usb_pipein(urb->pipe))
sched = &musb->in_bulk;
else
sched = &musb->out_bulk;
break;
}
default:
/* REVISIT when we get a schedule tree, periodic
* transfers won't always be at the head of a
* singleton queue...
*/
sched = NULL;
break;
}
}
/* NOTE: qh is invalid unless !list_empty(&hep->urb_list) */
if (ret < 0 || (sched && qh != first_qh(sched))) {
if (!qh->is_ready
|| urb->urb_list.prev != &qh->hep->urb_list
|| musb_ep_get_qh(qh->hw_ep, is_in) != qh) {
int ready = qh->is_ready;
ret = 0;
qh->is_ready = 0;
__musb_giveback(musb, urb, 0);
qh->is_ready = ready;
@ -2169,13 +2147,11 @@ done:
static void
musb_h_disable(struct usb_hcd *hcd, struct usb_host_endpoint *hep)
{
u8 epnum = hep->desc.bEndpointAddress;
u8 is_in = hep->desc.bEndpointAddress & USB_DIR_IN;
unsigned long flags;
struct musb *musb = hcd_to_musb(hcd);
u8 is_in = epnum & USB_DIR_IN;
struct musb_qh *qh;
struct urb *urb;
struct list_head *sched;
spin_lock_irqsave(&musb->lock, flags);
@ -2183,31 +2159,11 @@ musb_h_disable(struct usb_hcd *hcd, struct usb_host_endpoint *hep)
if (qh == NULL)
goto exit;
switch (qh->type) {
case USB_ENDPOINT_XFER_CONTROL:
sched = &musb->control;
break;
case USB_ENDPOINT_XFER_BULK:
if (qh->mux == 1) {
if (is_in)
sched = &musb->in_bulk;
else
sched = &musb->out_bulk;
break;
}
default:
/* REVISIT when we get a schedule tree, periodic transfers
* won't always be at the head of a singleton queue...
*/
sched = NULL;
break;
}
/* NOTE: qh is invalid unless !list_empty(&hep->urb_list) */
/* NOTE: qh is invalid unless !list_empty(&hep->urb_list) */
/* kick first urb off the hardware, if needed */
/* Kick the first URB off the hardware, if needed */
qh->is_ready = 0;
if (!sched || qh == first_qh(sched)) {
if (musb_ep_get_qh(qh->hw_ep, is_in) == qh) {
urb = next_urb(qh);
/* make software (then hardware) stop ASAP */