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author | Sergei Shtylyov <sshtylyov@ru.mvista.com> | 2009-03-27 12:52:43 -0700 |
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committer | Greg Kroah-Hartman <gregkh@suse.de> | 2009-06-15 21:44:39 -0700 |
commit | a5073b52833e4df8e16c93dc4cbb7e0c558c74a2 (patch) | |
tree | 5cd7e1f2aa6756a041677097138e2bb9a952f8d9 /drivers/usb/musb/musb_gadget_ep0.c | |
parent | 003051bfb62513842a9e9efde17afeba46519c95 (diff) | |
download | linux-a5073b52833e4df8e16c93dc4cbb7e0c558c74a2.tar.gz linux-a5073b52833e4df8e16c93dc4cbb7e0c558c74a2.tar.bz2 linux-a5073b52833e4df8e16c93dc4cbb7e0c558c74a2.zip |
musb_gadget: fix unhandled endpoint 0 IRQs
The gadget EP0 code routinely ignores an interrupt at end of
the data phase because of musb_g_ep0_giveback() resetting the
state machine to "idle, waiting for SETUP" phase prematurely.
The driver also prematurely leaves the status phase on
receiving the SetupEnd interrupt.
As there were still unhandled endpoint 0 interrupts happening
from time to time after fixing these issues, there turned to
be yet another culprit: two distinct gadget states collapsed
into one.
The (missing) state that comes after STATUS IN/OUT states was
typically indiscernible from them since the corresponding
interrupts tend to happen within too little period of time
(due to only a zero-length status packet in between) and so
they got coalesced; yet this state is not the same as the next
one which is associated with the reception of a SETUP packet.
Adding this extra state seems to have fixed the rest of the
unhandled interrupts that generic_interrupt() and
davinci_interrupt() hid by faking their result and only
emitting a debug message -- so, stop doing that.
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>
Diffstat (limited to 'drivers/usb/musb/musb_gadget_ep0.c')
-rw-r--r-- | drivers/usb/musb/musb_gadget_ep0.c | 45 |
1 files changed, 39 insertions, 6 deletions
diff --git a/drivers/usb/musb/musb_gadget_ep0.c b/drivers/usb/musb/musb_gadget_ep0.c index 3f5e30ddfa27..40ed50ecedff 100644 --- a/drivers/usb/musb/musb_gadget_ep0.c +++ b/drivers/usb/musb/musb_gadget_ep0.c @@ -4,6 +4,7 @@ * Copyright 2005 Mentor Graphics Corporation * Copyright (C) 2005-2006 by Texas Instruments * Copyright (C) 2006-2007 Nokia Corporation + * Copyright (C) 2008-2009 MontaVista Software, Inc. <source@mvista.com> * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License @@ -58,7 +59,8 @@ static char *decode_ep0stage(u8 stage) { switch (stage) { - case MUSB_EP0_STAGE_SETUP: return "idle"; + case MUSB_EP0_STAGE_IDLE: return "idle"; + case MUSB_EP0_STAGE_SETUP: return "setup"; case MUSB_EP0_STAGE_TX: return "in"; case MUSB_EP0_STAGE_RX: return "out"; case MUSB_EP0_STAGE_ACKWAIT: return "wait"; @@ -628,7 +630,7 @@ irqreturn_t musb_g_ep0_irq(struct musb *musb) musb_writew(regs, MUSB_CSR0, csr & ~MUSB_CSR0_P_SENTSTALL); retval = IRQ_HANDLED; - musb->ep0_state = MUSB_EP0_STAGE_SETUP; + musb->ep0_state = MUSB_EP0_STAGE_IDLE; csr = musb_readw(regs, MUSB_CSR0); } @@ -636,7 +638,18 @@ irqreturn_t musb_g_ep0_irq(struct musb *musb) if (csr & MUSB_CSR0_P_SETUPEND) { musb_writew(regs, MUSB_CSR0, MUSB_CSR0_P_SVDSETUPEND); retval = IRQ_HANDLED; - musb->ep0_state = MUSB_EP0_STAGE_SETUP; + /* Transition into the early status phase */ + switch (musb->ep0_state) { + case MUSB_EP0_STAGE_TX: + musb->ep0_state = MUSB_EP0_STAGE_STATUSOUT; + break; + case MUSB_EP0_STAGE_RX: + musb->ep0_state = MUSB_EP0_STAGE_STATUSIN; + break; + default: + ERR("SetupEnd came in a wrong ep0stage %s", + decode_ep0stage(musb->ep0_state)); + } csr = musb_readw(regs, MUSB_CSR0); /* NOTE: request may need completion */ } @@ -697,11 +710,31 @@ irqreturn_t musb_g_ep0_irq(struct musb *musb) if (req) musb_g_ep0_giveback(musb, req); } + + /* + * In case when several interrupts can get coalesced, + * check to see if we've already received a SETUP packet... + */ + if (csr & MUSB_CSR0_RXPKTRDY) + goto setup; + + retval = IRQ_HANDLED; + musb->ep0_state = MUSB_EP0_STAGE_IDLE; + break; + + case MUSB_EP0_STAGE_IDLE: + /* + * This state is typically (but not always) indiscernible + * from the status states since the corresponding interrupts + * tend to happen within too little period of time (with only + * a zero-length packet in between) and so get coalesced... + */ retval = IRQ_HANDLED; musb->ep0_state = MUSB_EP0_STAGE_SETUP; /* FALLTHROUGH */ case MUSB_EP0_STAGE_SETUP: +setup: if (csr & MUSB_CSR0_RXPKTRDY) { struct usb_ctrlrequest setup; int handled = 0; @@ -783,7 +816,7 @@ irqreturn_t musb_g_ep0_irq(struct musb *musb) stall: DBG(3, "stall (%d)\n", handled); musb->ackpend |= MUSB_CSR0_P_SENDSTALL; - musb->ep0_state = MUSB_EP0_STAGE_SETUP; + musb->ep0_state = MUSB_EP0_STAGE_IDLE; finish: musb_writew(regs, MUSB_CSR0, musb->ackpend); @@ -803,7 +836,7 @@ finish: /* "can't happen" */ WARN_ON(1); musb_writew(regs, MUSB_CSR0, MUSB_CSR0_P_SENDSTALL); - musb->ep0_state = MUSB_EP0_STAGE_SETUP; + musb->ep0_state = MUSB_EP0_STAGE_IDLE; break; } @@ -959,7 +992,7 @@ static int musb_g_ep0_halt(struct usb_ep *e, int value) csr |= MUSB_CSR0_P_SENDSTALL; musb_writew(regs, MUSB_CSR0, csr); - musb->ep0_state = MUSB_EP0_STAGE_SETUP; + musb->ep0_state = MUSB_EP0_STAGE_IDLE; musb->ackpend = 0; break; default: |