On Friday, August 27, 2010 07:37:20 [email protected] wrote: > From: Ming Lei <[email protected]> > > This patch fixes one infinite hang of bulk IN transfer in double buffer > case, the hang can be observed easily by test #6 of usbtest if musb is > configured as g_zero and fifo mode 3 is taken to enable double fifo. > > In fact, the patch only removes the check for non-empty fifo before > loading data from new request into fifo since the check is not correct: > > -in double buffer case, fifo may accommodate more than one packet, > even though it has contained one packet already and is non-empty > > -since last DMA is completed before calling musb_g_tx, it is sure > that fifo may accommodate at least one packet > > Without applying the patch, new requst enqueued from .complte may not > have a chance to be loaded into fifo, then will never be completed and > cause infinite hangs. > > With the patch, on my beagle B5, test#6(queued bulk in) can be passed and > test result may go beyond 33Mbyte/s if musb is configured as g_zero and > fifo mode 3 is taken, follows the test command: > > #testusb -D DEV_NAME -c 1024 -t 6 -s 32768 -g 8 [1] > > [1], > -source of testusb : tools/usb/testusb.c under linux kernel; > > Signed-off-by: Ming Lei <[email protected]> > Cc: Anand Gadiyar <[email protected]> > Cc: Mike Frysinger <[email protected]> > Cc: Sergei Shtylyov <[email protected]> > > --- > drivers/usb/musb/musb_gadget.c | 12 ------------ > 1 files changed, 0 insertions(+), 12 deletions(-) > > diff --git a/drivers/usb/musb/musb_gadget.c > b/drivers/usb/musb/musb_gadget.c index 550b397..e0bd1c1 100644 > --- a/drivers/usb/musb/musb_gadget.c > +++ b/drivers/usb/musb/musb_gadget.c > @@ -506,18 +506,6 @@ void musb_g_tx(struct musb *musb, u8 epnum) > /* ... or if not, then complete it. */ > musb_g_giveback(musb_ep, request, 0); > > - /* > - * Kickstart next transfer if appropriate; > - * the packet that just completed might not > - * be transmitted for hours or days. > - * REVISIT for double buffering... > - * FIXME revisit for stalls too... > - */ > - musb_ep_select(mbase, epnum); > - csr = musb_readw(epio, MUSB_TXCSR); > - if (csr & MUSB_TXCSR_FIFONOTEMPTY) > - return; > - > request = musb_ep->desc ? next_request(musb_ep) : NULL; > if (!request) { > DBG(4, "%s idle now\n",
maybe this change will make a difference ? From 13fa6c9cec387893e2b22db6c055028f96fea5b8 Mon Sep 17 00:00:00 2001 From: Cliff Cai <[email protected]> Date: Fri, 3 Jul 2009 06:32:02 +0000 Subject: [PATCH] USB: musb: only complete the request when all data has been transfered [local/log] bug[#5269],bug[#5268],bug[#5264]only complete the request when all data has been transfered git-svn-id: svn://localhost/svn/linux-kernel/tr...@6915 526b6c2d-f592-4532- a319-5dd88ccb003d --- drivers/usb/musb/musb_gadget.c | 2 ++ 1 files changed, 2 insertions(+), 0 deletions(-) diff --git a/drivers/usb/musb/musb_gadget.c b/drivers/usb/musb/musb_gadget.c index 6fca870..f019843 100644 --- a/drivers/usb/musb/musb_gadget.c +++ b/drivers/usb/musb/musb_gadget.c @@ -500,6 +500,8 @@ void musb_g_tx(struct musb *musb, u8 epnum) | MUSB_TXCSR_TXPKTRDY); request->zero = 0; } + if (request->actual < request->length) + return; /* ... or if not, then complete it. */ musb_g_giveback(musb_ep, request, 0); -- 1.7.2.2
signature.asc
Description: This is a digitally signed message part.
