From 0bcfeb3ec9467a8dfae3e906925ec28fe788afcf Mon Sep 17 00:00:00 2001 From: David Brownell Date: Tue, 26 Aug 2008 14:43:46 -0700 Subject: USB: ehci: fix some ehci hangs and crashes I noticed that the "Refactor "if (handshake()) state = HC_STATE_HALT" patch from earlier this year perpetuated a potential problem: it can mark the controller as halted when it's still running (but not acting as, perhaps wrongly, expected). That caused some hangs and crashes, rather than more polite failure modes of a truly halted controller. This patch forces a true halt, and emits a (previously missing) diagnostic. Signed-off-by: David Brownell Signed-off-by: Greg Kroah-Hartman --- drivers/usb/host/ehci-hcd.c | 26 ++++++++++++++++---------- 1 file changed, 16 insertions(+), 10 deletions(-) (limited to 'drivers/usb/host') diff --git a/drivers/usb/host/ehci-hcd.c b/drivers/usb/host/ehci-hcd.c index d9d53f289ca..8409e0705d6 100644 --- a/drivers/usb/host/ehci-hcd.c +++ b/drivers/usb/host/ehci-hcd.c @@ -145,16 +145,6 @@ static int handshake (struct ehci_hcd *ehci, void __iomem *ptr, return -ETIMEDOUT; } -static int handshake_on_error_set_halt(struct ehci_hcd *ehci, void __iomem *ptr, - u32 mask, u32 done, int usec) -{ - int error = handshake(ehci, ptr, mask, done, usec); - if (error) - ehci_to_hcd(ehci)->state = HC_STATE_HALT; - - return error; -} - /* force HC to halt state from unknown (EHCI spec section 2.3) */ static int ehci_halt (struct ehci_hcd *ehci) { @@ -173,6 +163,22 @@ static int ehci_halt (struct ehci_hcd *ehci) STS_HALT, STS_HALT, 16 * 125); } +static int handshake_on_error_set_halt(struct ehci_hcd *ehci, void __iomem *ptr, + u32 mask, u32 done, int usec) +{ + int error; + + error = handshake(ehci, ptr, mask, done, usec); + if (error) { + ehci_halt(ehci); + ehci_to_hcd(ehci)->state = HC_STATE_HALT; + ehci_err(ehci, "force halt; handhake %p %08x %08x -> %d\n", + ptr, mask, done, error); + } + + return error; +} + /* put TDI/ARC silicon into EHCI mode */ static void tdi_reset (struct ehci_hcd *ehci) { -- cgit v1.2.3 From 01c17142659c02d8cd4c67acdd8358180c5c4fb6 Mon Sep 17 00:00:00 2001 From: David Brownell Date: Tue, 26 Aug 2008 23:35:04 -0700 Subject: USB: fix EHCI periodic transfers As noted by Stefan Neis , we had a recent regression with EHCI periodic transfers, in some (seemingly not all that common) cases. The root cause was that the schedule activation was only loosely coupled to the addition or removal of transfers, so two different execution contexts could both think they had to deactivate (or conversely activate) the schedule. So this fix tightens that coupling, managing it more like a refcount. Signed-off-by: David Brownell Signed-off-by: Greg Kroah-Hartman --- drivers/usb/host/ehci-sched.c | 32 ++++++++++++++------------------ 1 file changed, 14 insertions(+), 18 deletions(-) (limited to 'drivers/usb/host') diff --git a/drivers/usb/host/ehci-sched.c b/drivers/usb/host/ehci-sched.c index b7853c8bac0..4a0c5a78b2e 100644 --- a/drivers/usb/host/ehci-sched.c +++ b/drivers/usb/host/ehci-sched.c @@ -437,6 +437,9 @@ static int enable_periodic (struct ehci_hcd *ehci) u32 cmd; int status; + if (ehci->periodic_sched++) + return 0; + /* did clearing PSE did take effect yet? * takes effect only at frame boundaries... */ @@ -461,6 +464,9 @@ static int disable_periodic (struct ehci_hcd *ehci) u32 cmd; int status; + if (--ehci->periodic_sched) + return 0; + /* did setting PSE not take effect yet? * takes effect only at frame boundaries... */ @@ -544,13 +550,10 @@ static int qh_link_periodic (struct ehci_hcd *ehci, struct ehci_qh *qh) : (qh->usecs * 8); /* maybe enable periodic schedule processing */ - if (!ehci->periodic_sched++) - return enable_periodic (ehci); - - return 0; + return enable_periodic(ehci); } -static void qh_unlink_periodic (struct ehci_hcd *ehci, struct ehci_qh *qh) +static int qh_unlink_periodic(struct ehci_hcd *ehci, struct ehci_qh *qh) { unsigned i; unsigned period; @@ -586,9 +589,7 @@ static void qh_unlink_periodic (struct ehci_hcd *ehci, struct ehci_qh *qh) qh_put (qh); /* maybe turn off periodic schedule */ - ehci->periodic_sched--; - if (!ehci->periodic_sched) - (void) disable_periodic (ehci); + return disable_periodic(ehci); } static void intr_deschedule (struct ehci_hcd *ehci, struct ehci_qh *qh) @@ -1562,9 +1563,7 @@ itd_link_urb ( urb->hcpriv = NULL; timer_action (ehci, TIMER_IO_WATCHDOG); - if (unlikely (!ehci->periodic_sched++)) - return enable_periodic (ehci); - return 0; + return enable_periodic(ehci); } #define ISO_ERRS (EHCI_ISOC_BUF_ERR | EHCI_ISOC_BABBLE | EHCI_ISOC_XACTERR) @@ -1642,7 +1641,7 @@ itd_complete ( ehci_urb_done(ehci, urb, 0); retval = true; urb = NULL; - ehci->periodic_sched--; + (void) disable_periodic(ehci); ehci_to_hcd(ehci)->self.bandwidth_isoc_reqs--; if (unlikely (list_empty (&stream->td_list))) { @@ -1951,9 +1950,7 @@ sitd_link_urb ( urb->hcpriv = NULL; timer_action (ehci, TIMER_IO_WATCHDOG); - if (!ehci->periodic_sched++) - return enable_periodic (ehci); - return 0; + return enable_periodic(ehci); } /*-------------------------------------------------------------------------*/ @@ -2019,7 +2016,7 @@ sitd_complete ( ehci_urb_done(ehci, urb, 0); retval = true; urb = NULL; - ehci->periodic_sched--; + (void) disable_periodic(ehci); ehci_to_hcd(ehci)->self.bandwidth_isoc_reqs--; if (list_empty (&stream->td_list)) { @@ -2243,8 +2240,7 @@ restart: if (unlikely (modified)) { if (likely(ehci->periodic_sched > 0)) goto restart; - /* maybe we can short-circuit this scan! */ - disable_periodic(ehci); + /* short-circuit this scan */ now_uframe = clock; break; } -- cgit v1.2.3