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USB: musb: rewrite host periodic endpoint allocation

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The current MUSB host code doesn't make use of all the available
FIFOs in for periodic transfers since it wrongly assumes the RX
and TX sides of any given hw_ep always share one FIFO.

Change:  use 'in_qh' and 'out_qh' fields of the 'struct musb_hw_ep'
to check the endpoint's business; get rid of the now-unused 'periodic'
array in the 'struct musb'.  Also optimize a loop induction variable
in the endpoint lookup code.

(Based on a previous patch from Ajay Kumar Gupta <ajay.gupta@ti.com>)

[ dbrownell@users.sourceforge.net: clarify description and origin
  of this fix; whitespace ]

Signed-off-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Cc: Felipe Balbi <felipe.balbi@nokia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This commit is contained in:
Sergei Shtylyov 2009-02-24 15:23:34 -08:00 committed by Greg Kroah-Hartman
parent b2bdf3a789
commit 5d67a851bc
2 changed files with 11 additions and 18 deletions
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1
drivers/usb/musb/musb_core.h
View File

@ -331,7 +331,6 @@ struct musb {
struct list_head control; /* of musb_qh */
struct list_head in_bulk; /* of musb_qh */
struct list_head out_bulk; /* of musb_qh */
struct musb_qh *periodic[32]; /* tree of interrupt+iso */
#endif
/* called with IRQs blocked; ON/nonzero implies starting a session,

28
drivers/usb/musb/musb_host.c
View File

@ -395,7 +395,6 @@ musb_giveback(struct musb_qh *qh, struct urb *urb, int status)
* de-allocated if it's tracked and allocated;
* and where we'd update the schedule tree...
*/
musb->periodic[ep->epnum] = NULL;
kfree(qh);
qh = NULL;
break;
@ -1711,31 +1710,27 @@ static int musb_schedule(
/* else, periodic transfers get muxed to other endpoints */
/* FIXME this doesn't consider direction, so it can only
* work for one half of the endpoint hardware, and assumes
* the previous cases handled all non-shared endpoints...
*/
/* we know this qh hasn't been scheduled, so all we need to do
/*
* We know this qh hasn't been scheduled, so all we need to do
* is choose which hardware endpoint to put it on ...
*
* REVISIT what we really want here is a regular schedule tree
* like e.g. OHCI uses, but for now musb->periodic is just an
* array of the _single_ logical endpoint associated with a
* given physical one (identity mapping logical->physical).
*
* that simplistic approach makes TT scheduling a lot simpler;
* there is none, and thus none of its complexity...
* like e.g. OHCI uses.
*/
best_diff = 4096;
best_end = -1;
for (epnum = 1; epnum < musb->nr_endpoints; epnum++) {
for (epnum = 1, hw_ep = musb->endpoints + 1;
epnum < musb->nr_endpoints;
epnum++, hw_ep++) {
int diff;
if (musb->periodic[epnum])
if (is_in || hw_ep->is_shared_fifo) {
if (hw_ep->in_qh != NULL)
continue;
} else if (hw_ep->out_qh != NULL)
continue;
hw_ep = &musb->endpoints[epnum];
if (hw_ep == musb->bulk_ep)
continue;
@ -1764,7 +1759,6 @@ static int musb_schedule(
idle = 1;
qh->mux = 0;
hw_ep = musb->endpoints + best_end;
musb->periodic[best_end] = qh;
DBG(4, "qh %p periodic slot %d\n", qh, best_end);
success:
if (head) {