From akpm@osdl.org Thu Aug 4 16:53:19 2005 Message-Id: <200508042352.j74NqA2T016547@shell0.pdx.osdl.net> Subject: USB: ehci: microframe handling fix To: greg@kroah.com Cc: akpm@osdl.org, david-b@pacbell.net, dbrownell@users.sourceforge.net From: David Brownell Date: Thu, 4 Aug 2005 16:54:14 -0700 This patch has a one line oops fix, plus related cleanups. - The bugfix uses microframe scheduling data given to the hardware to test "is this a periodic QH", rather than testing for nonzero period. (Prevents an oops by providing the correct answer.) - The cleanup going along with the patch should make it clearer what's going on whenever those bitfields are accessed. The bug came about when, around January, two new kinds of EHCI interrupt scheduling operation were added, involving both the high speed (24 KBytes per millisec) and low/full speed (1-64 bytes per millisec) microframe scheduling. A driver for the Edirol UA-1000 Audio Capture Unit ran into the oops; it used one of the newly supported high speed modes. Signed-off-by: David Brownell Signed-off-by: Andrew Morton Signed-off-by: Greg Kroah-Hartman --- drivers/usb/host/ehci-dbg.c | 2 +- drivers/usb/host/ehci-q.c | 5 +++-- drivers/usb/host/ehci-sched.c | 13 +++++++------ drivers/usb/host/ehci.h | 5 +++++ 4 files changed, 16 insertions(+), 9 deletions(-) --- gregkh-2.6.orig/drivers/usb/host/ehci-dbg.c 2005-08-02 13:41:29.000000000 -0700 +++ gregkh-2.6/drivers/usb/host/ehci-dbg.c 2005-08-04 17:27:43.000000000 -0700 @@ -527,7 +527,7 @@ p.qh->period, le32_to_cpup (&p.qh->hw_info2) /* uframe masks */ - & 0xffff, + & (QH_CMASK | QH_SMASK), p.qh); size -= temp; next += temp; --- gregkh-2.6.orig/drivers/usb/host/ehci.h 2005-06-17 12:48:29.000000000 -0700 +++ gregkh-2.6/drivers/usb/host/ehci.h 2005-08-04 17:27:43.000000000 -0700 @@ -385,6 +385,11 @@ __le32 hw_info1; /* see EHCI 3.6.2 */ #define QH_HEAD 0x00008000 __le32 hw_info2; /* see EHCI 3.6.2 */ +#define QH_SMASK 0x000000ff +#define QH_CMASK 0x0000ff00 +#define QH_HUBADDR 0x007f0000 +#define QH_HUBPORT 0x3f800000 +#define QH_MULT 0xc0000000 __le32 hw_current; /* qtd list - see EHCI 3.6.4 */ /* qtd overlay (hardware parts of a struct ehci_qtd) */ --- gregkh-2.6.orig/drivers/usb/host/ehci-q.c 2005-08-02 13:41:29.000000000 -0700 +++ gregkh-2.6/drivers/usb/host/ehci-q.c 2005-08-04 17:27:43.000000000 -0700 @@ -222,7 +222,7 @@ struct ehci_qh *qh = (struct ehci_qh *) urb->hcpriv; /* S-mask in a QH means it's an interrupt urb */ - if ((qh->hw_info2 & __constant_cpu_to_le32 (0x00ff)) != 0) { + if ((qh->hw_info2 & __constant_cpu_to_le32 (QH_SMASK)) != 0) { /* ... update hc-wide periodic stats (for usbfs) */ ehci_to_hcd(ehci)->self.bandwidth_int_reqs--; @@ -428,7 +428,8 @@ /* should be rare for periodic transfers, * except maybe high bandwidth ... */ - if (qh->period) { + if ((__constant_cpu_to_le32 (QH_SMASK) + & qh->hw_info2) != 0) { intr_deschedule (ehci, qh); (void) qh_schedule (ehci, qh); } else --- gregkh-2.6.orig/drivers/usb/host/ehci-sched.c 2005-08-02 13:41:29.000000000 -0700 +++ gregkh-2.6/drivers/usb/host/ehci-sched.c 2005-08-04 17:27:43.000000000 -0700 @@ -301,7 +301,7 @@ dev_dbg (&qh->dev->dev, "link qh%d-%04x/%p start %d [%d/%d us]\n", - period, le32_to_cpup (&qh->hw_info2) & 0xffff, + period, le32_to_cpup (&qh->hw_info2) & (QH_CMASK | QH_SMASK), qh, qh->start, qh->usecs, qh->c_usecs); /* high bandwidth, or otherwise every microframe */ @@ -385,7 +385,8 @@ dev_dbg (&qh->dev->dev, "unlink qh%d-%04x/%p start %d [%d/%d us]\n", - qh->period, le32_to_cpup (&qh->hw_info2) & 0xffff, + qh->period, + le32_to_cpup (&qh->hw_info2) & (QH_CMASK | QH_SMASK), qh, qh->start, qh->usecs, qh->c_usecs); /* qh->qh_next still "live" to HC */ @@ -411,7 +412,7 @@ * active high speed queues may need bigger delays... */ if (list_empty (&qh->qtd_list) - || (__constant_cpu_to_le32 (0x0ff << 8) + || (__constant_cpu_to_le32 (QH_CMASK) & qh->hw_info2) != 0) wait = 2; else @@ -533,7 +534,7 @@ /* reuse the previous schedule slots, if we can */ if (frame < qh->period) { - uframe = ffs (le32_to_cpup (&qh->hw_info2) & 0x00ff); + uframe = ffs (le32_to_cpup (&qh->hw_info2) & QH_SMASK); status = check_intr_schedule (ehci, frame, --uframe, qh, &c_mask); } else { @@ -569,10 +570,10 @@ qh->start = frame; /* reset S-frame and (maybe) C-frame masks */ - qh->hw_info2 &= __constant_cpu_to_le32 (~0xffff); + qh->hw_info2 &= __constant_cpu_to_le32(~(QH_CMASK | QH_SMASK)); qh->hw_info2 |= qh->period ? cpu_to_le32 (1 << uframe) - : __constant_cpu_to_le32 (0xff); + : __constant_cpu_to_le32 (QH_SMASK); qh->hw_info2 |= c_mask; } else ehci_dbg (ehci, "reused qh %p schedule\n", qh);