The patch titled usb: ehci tolerates some buggy devices has been removed from the -mm tree. Its filename was usb-ehci-tolerates-some-buggy-devices.patch This patch was dropped because it was merged into mainline or a subsystem tree The current -mm tree may be found at http://userweb.kernel.org/~akpm/mmotm/ ------------------------------------------------------ Subject: usb: ehci tolerates some buggy devices From: David Brownell <david-b@xxxxxxxxxxx> This teaches EHCI how to to work around bugs in certain high speed devices, by accomodating "bulk" packets that exceed the 512 byte constant value required by the USB 2.0 specification. (Have a look at section 5.8.3, paragraphs 1 and 3.) It also makes the descriptor parsing code warn when it encounters such bugs. (We've had reports of maybe two or three such devices, all pretty recent.) Such devices are nonconformant. The proper fix is have the vendors of those devices do the simple, obvious, and correct thing ... which will let them be used with USB hosts that don't have workarounds for this particular vendor bug. But unless/until they do, we can at least have one of the high speed HCDs work with such buggy devices. Signed-off-by: David Brownell <dbrownell@xxxxxxxxxxxxxxxxxxxxx> Cc: Andy Shevchenko <andy@xxxxxxxxxxxx> Cc: Gosne Stephane <sgosne@xxxxxxxxxxx> Cc: Alan Stern <stern@xxxxxxxxxxxxxxxxxxx> Cc: Greg KH <greg@xxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- drivers/usb/core/config.c | 17 +++++++++++++++++ drivers/usb/host/ehci-q.c | 16 +++++++++++++++- 2 files changed, 32 insertions(+), 1 deletion(-) diff -puN drivers/usb/core/config.c~usb-ehci-tolerates-some-buggy-devices drivers/usb/core/config.c --- a/drivers/usb/core/config.c~usb-ehci-tolerates-some-buggy-devices +++ a/drivers/usb/core/config.c @@ -145,6 +145,23 @@ static int usb_parse_endpoint(struct dev endpoint->desc.wMaxPacketSize = cpu_to_le16(8); } + /* + * Some buggy high speed devices have bulk endpoints using + * maxpacket sizes other than 512. High speed HCDs may not + * be able to handle that particular bug, so let's warn... + */ + if (to_usb_device(ddev)->speed == USB_SPEED_HIGH + && usb_endpoint_xfer_bulk(d)) { + unsigned maxp; + + maxp = le16_to_cpu(endpoint->desc.wMaxPacketSize) & 0x07ff; + if (maxp != 512) + dev_warn(ddev, "config %d interface %d altsetting %d " + "bulk endpoint 0x%X has invalid maxpacket %d\n", + cfgno, inum, asnum, d->bEndpointAddress, + maxp); + } + /* Skip over any Class Specific or Vendor Specific descriptors; * find the next endpoint or interface descriptor */ endpoint->extra = buffer; diff -puN drivers/usb/host/ehci-q.c~usb-ehci-tolerates-some-buggy-devices drivers/usb/host/ehci-q.c --- a/drivers/usb/host/ehci-q.c~usb-ehci-tolerates-some-buggy-devices +++ a/drivers/usb/host/ehci-q.c @@ -657,6 +657,14 @@ qh_make ( type = usb_pipetype (urb->pipe); maxp = usb_maxpacket (urb->dev, urb->pipe, !is_input); + /* 1024 byte maxpacket is a hardware ceiling. High bandwidth + * acts like up to 3KB, but is built from smaller packets. + */ + if (max_packet(maxp) > 1024) { + ehci_dbg(ehci, "bogus qh maxpacket %d\n", max_packet(maxp)); + goto done; + } + /* Compute interrupt scheduling parameters just once, and save. * - allowing for high bandwidth, how many nsec/uframe are used? * - split transactions need a second CSPLIT uframe; same question @@ -757,7 +765,13 @@ qh_make ( info2 |= (EHCI_TUNE_MULT_HS << 30); } else if (type == PIPE_BULK) { info1 |= (EHCI_TUNE_RL_HS << 28); - info1 |= 512 << 16; /* usb2 fixed maxpacket */ + /* The USB spec says that high speed bulk endpoints + * always use 512 byte maxpacket. But some device + * vendors decided to ignore that, and MSFT is happy + * to help them do so. So now people expect to use + * such nonconformant devices with Linux too; sigh. + */ + info1 |= max_packet(maxp) << 16; info2 |= (EHCI_TUNE_MULT_HS << 30); } else { /* PIPE_INTERRUPT */ info1 |= max_packet (maxp) << 16; _ Patches currently in -mm which might be from david-b@xxxxxxxxxxx are origin.patch atmel_spi-fix-clock-polarity.patch git-acpi.patch at91-correct-at91sam9263ek-lcd-power-gpio-pin.patch git-avr32.patch i2c-isp1301_omap-new-style-i2c-driver-updates-part-1.patch usb-net-asix-does-not-really-need-10-100mbit.patch rtc-cmos-display-hpet-emulation-mode.patch spi-pxa2xx_spi-sparse-fixes.patch rtc-avoid-legacy-drivers-with-generic-framework.patch rtc-add-support-for-the-s-35390a-rtc-chip.patch rtc-add-support-for-the-s-35390a-rtc-chip-checkpatch-fixes.patch rtc-isl1208-new-style-conversion-and-minor-bug-fixes.patch rtc-isl1208-new-style-conversion-and-minor-bug-fixes-checkpatch-fixes.patch rtc-pcf8563-new-style-conversion.patch rtc-pcf8563-new-style-conversion-checkpatch-fixes.patch rtc-pcf8563-new-style-conversion-checkpatch-fixes-fix.patch rtc-x1205-new-style-conversion.patch rtc-x1205-new-style-conversion-checkpatch-fixes.patch rtc-silence-section-mismatch-warning-in-rtc-test.patch make-ds1511_rtc_readset_time-static.patch - To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html