07 May, 2011

2 commits

  • This patch is part of a series that extend the UHCI HCD to support
    non-PCI controllers.

    This patch replaces in{b,w,l} and out{b,wl} with calls to local inline
    functions. This is done so that the register access functions can be
    extended to support register areas not mapped in PCI I/O space.

    Signed-off-by: Jan Andersson
    Acked-by: Alan Stern
    Signed-off-by: Greg Kroah-Hartman

    Jan Andersson
     
  • This patch is part of a series that extend the UHCI HCD to support
    non-PCI host controllers.

    uhci-hub.c contained two PCI vendor checks for silicon quirks. Move
    these checks into uhci-hcd.c and use bits in uhci_hcd structure to
    mark that we need to use the quirks.

    This patch is followed by other patches that will remove PCI
    dependencies from uhci-hcd.c as well.

    Signed-off-by: Jan Andersson
    Acked-by: Alan Stern
    Signed-off-by: Greg Kroah-Hartman

    Jan Andersson
     

11 Aug, 2010

2 commits

  • This patch (as1394) adds code to ehci-hcd, ohci-hcd, and uhci-hcd for
    automatically resuming the root hub when the controller is resumed, if
    the root hub has a wakeup request pending on some port.

    During resume from system sleep this doesn't matter, because the root
    hubs will naturally be resumed along with every other device in the
    system. However it _will_ matter for runtime PM: If the controller is
    suspended and a remote wakeup request is received then the controller
    will autoresume, but we need to ensure that the root hub also
    autoresumes. Otherwise the wakeup request would be ignored, the
    controller would go back to sleep, and the cycle would repeat a large
    number of times (I saw this happen before the patch was written).

    Signed-off-by: Alan Stern
    Signed-off-by: Greg Kroah-Hartman

    Alan Stern
     
  • This patch (as1393) converts several of the single-bit fields in
    struct usb_hcd to atomic flags. This is for safety's sake; not all
    CPUs can update bitfield values atomically, and these flags are used
    in multiple contexts.

    The flag fields that are set only during registration or removal can
    remain as they are, since non-atomic accesses at those times will not
    cause any problems.

    (Strictly speaking, the authorized_default flag should become atomic
    as well. I didn't bother with it because it gets changed only via
    sysfs. It can be done later, if anyone wants.)

    Signed-off-by: Alan Stern
    Signed-off-by: Greg Kroah-Hartman

    Alan Stern
     

21 Jan, 2010

1 commit

  • This patch (as1330) fixes a bug in khbud's handling of remote
    wakeups. When a device sends a remote-wakeup request, the parent hub
    (or the host controller driver, for directly attached devices) begins
    the resume sequence and notifies khubd when the sequence finishes. At
    this point the port's SUSPEND feature is automatically turned off.

    However the device needs an additional 10-ms resume-recovery time
    (TRSMRCY in the USB spec). Khubd does not wait for this delay if the
    SUSPEND feature is off, and as a result some devices fail to behave
    properly following a remote wakeup. This patch adds the missing
    delay to the remote-wakeup path.

    It also extends the resume-signalling delay used by ehci-hcd and
    uhci-hcd from 20 ms (the value in the spec) to 25 ms (the value we use
    for non-remote-wakeup resumes). The extra time appears to help some
    devices.

    Signed-off-by: Alan Stern
    Cc: stable
    Cc: Rickard Bellini
    Signed-off-by: Greg Kroah-Hartman

    Alan Stern
     

22 Jul, 2008

1 commit


10 Mar, 2007

1 commit

  • This patch (as863) fixes a problem encountered sometimes when resuming
    a port on a UHCI controller. The hardware may turn off the
    Resume-Detect bit before turning off the Suspend bit, leading usbcore
    to think that the port is still suspended and the resume has failed.
    The patch makes uhci_finish_suspend() wait until both bits are safely
    off.

    Signed-off-by: Alan Stern
    Signed-off-by: Greg Kroah-Hartman

    Alan Stern
     

21 Dec, 2006

1 commit

  • Certain boards seem to like to issue false overcurrent notifications,
    for example on ports that don't have anything connected to them. This
    looks like a hardware error, at the level of noise to those ports'
    overcurrent input signals (or non-debounced VBUS comparators). This
    surfaces to users as truly massive amounts of syslog spam from khubd
    (which is appropriate for real hardware problems, except for the
    volume from multiple ports).

    Using this new "ignore_oc" flag helps such systems work more sanely,
    by preventing such indications from getting to khubd (and spamming
    syslog). The downside is of course that true overcurrent errors will
    be masked; they'll appear as spontaneous disconnects, without the
    diagnostics that will let users troubleshoot issues like
    short-circuited cables. In addition, controllers with no devices
    attached will be forced to poll for new devices rather than relying on
    interrupts, since each overcurrent event would generate a new
    interrupt.

    This patch (as826) is essentially a copy of David Brownell's ignore_oc
    patch for ehci-hcd, ported to uhci-hcd.

    Signed-off-by: Alan Stern
    Signed-off-by: Greg Kroah-Hartman

    Alan Stern
     

05 Oct, 2006

1 commit

  • Maintain a per-CPU global "struct pt_regs *" variable which can be used instead
    of passing regs around manually through all ~1800 interrupt handlers in the
    Linux kernel.

    The regs pointer is used in few places, but it potentially costs both stack
    space and code to pass it around. On the FRV arch, removing the regs parameter
    from all the genirq function results in a 20% speed up of the IRQ exit path
    (ie: from leaving timer_interrupt() to leaving do_IRQ()).

    Where appropriate, an arch may override the generic storage facility and do
    something different with the variable. On FRV, for instance, the address is
    maintained in GR28 at all times inside the kernel as part of general exception
    handling.

    Having looked over the code, it appears that the parameter may be handed down
    through up to twenty or so layers of functions. Consider a USB character
    device attached to a USB hub, attached to a USB controller that posts its
    interrupts through a cascaded auxiliary interrupt controller. A character
    device driver may want to pass regs to the sysrq handler through the input
    layer which adds another few layers of parameter passing.

    I've build this code with allyesconfig for x86_64 and i386. I've runtested the
    main part of the code on FRV and i386, though I can't test most of the drivers.
    I've also done partial conversion for powerpc and MIPS - these at least compile
    with minimal configurations.

    This will affect all archs. Mostly the changes should be relatively easy.
    Take do_IRQ(), store the regs pointer at the beginning, saving the old one:

    struct pt_regs *old_regs = set_irq_regs(regs);

    And put the old one back at the end:

    set_irq_regs(old_regs);

    Don't pass regs through to generic_handle_irq() or __do_IRQ().

    In timer_interrupt(), this sort of change will be necessary:

    - update_process_times(user_mode(regs));
    - profile_tick(CPU_PROFILING, regs);
    + update_process_times(user_mode(get_irq_regs()));
    + profile_tick(CPU_PROFILING);

    I'd like to move update_process_times()'s use of get_irq_regs() into itself,
    except that i386, alone of the archs, uses something other than user_mode().

    Some notes on the interrupt handling in the drivers:

    (*) input_dev() is now gone entirely. The regs pointer is no longer stored in
    the input_dev struct.

    (*) finish_unlinks() in drivers/usb/host/ohci-q.c needs checking. It does
    something different depending on whether it's been supplied with a regs
    pointer or not.

    (*) Various IRQ handler function pointers have been moved to type
    irq_handler_t.

    Signed-Off-By: David Howells
    (cherry picked from 1b16e7ac850969f38b375e511e3fa2f474a33867 commit)

    David Howells
     

28 Sep, 2006

1 commit

  • The UHCI controller in my laptop takes longer to turn off the
    Resume-Detect bit than the 4 us allowed by uhci-hcd. Presumably other
    computers will have the same problem.

    This patch (as752) increases the maximum delay to 10 us, which should be
    plenty, and uses polling to avoid penalizing systems which can turn the
    bit off more quickly.

    Signed-off-by: Alan Stern
    Signed-off-by: Greg Kroah-Hartman

    Alan Stern
     

22 Jun, 2006

2 commits

  • This patch (as706) removes the private hc_inaccessible flag from
    uhci-hcd. It's not needed because it conveys exactly the same
    information as the generic HCD_FLAG_HW_ACCESSIBLE bit.

    In its place goes a new flag recording whether the controller is dead.
    The new code allows a complete device reset to resurrect a dead
    controller (although usbcore doesn't yet implement such a facility).

    Signed-off-by: Alan Stern
    Signed-off-by: Greg Kroah-Hartman

    Alan Stern
     
  • This patch (as683) re-implements Full-Speed Bandwidth Reclamation (FSBR)
    properly. It keeps track of which endpoint queues have advanced, and
    when none have advanced for a sufficiently long time, FSBR is turned
    off. The next TD on each of the non-moving queues is modified to
    generate an interrupt on completion, so that FSBR can be re-enabled as
    soon as the hardware starts to make some progress.

    Signed-off-by: Alan Stern
    Signed-off-by: Greg Kroah-Hartman

    Alan Stern
     

15 Apr, 2006

1 commit

  • Someone recently posted a bug report where it turned out that uhci-hcd
    was disagreeing with the UHCI controller over whether or not a port was
    suspended: The driver thought it wasn't and the hardware thought it was.
    This patch (as665) fixes the problem and simplifies the driver by
    removing the internal state-tracking completely. Now the driver just
    asks the hardware whether a port is suspended.

    Signed-off-by: Alan Stern
    Signed-off-by: Greg Kroah-Hartman

    Alan Stern
     

21 Mar, 2006

1 commit


13 Sep, 2005

1 commit

  • This patch (as558) removes from the UHCI driver a kernel timer used for
    checking Full Speed Bandwidth Reclamation (FSBR). The checking can be
    done during normal root-hub polling; it doesn't need a separate timer.

    Signed-off-by: Alan Stern
    Signed-off-by: Greg Kroah-Hartman

    Alan Stern
     

28 Jun, 2005

4 commits

  • This patch, which has as478b as a prerequisite, enables the uhci-hcd
    driver to take advantage of root-hub IRQs rather than polling during the
    time it is suspended. (Unfortunately the hardware doesn't support
    port-change interrupts while the controller is running.) It also turns
    off the driver's private timer while the controller is suspended, as it
    isn't needed then. The combined elimination of polling interrupts and
    timer interrupts ought to be enough to allow some systems to save a
    noticeable amount of power while they are otherwise idle.

    Signed-off-by: Alan Stern
    Signed-off-by: Greg Kroah-Hartman

    Alan Stern
     
  • This patch implements (finally!) separate suspend and resume routines
    for the root hub and the controller in the UHCI driver. It also
    changes the sequence used to reset the controller during initial
    probing, so as to preserve the existing state during a Resume-From-Disk.
    (This new sequence is what should be used in the PCI Quirks code for
    early USB handoffs, incidentally.) Lastly it adds a notion of the
    controller being "inaccessible" while in a PCI low-power state, when
    normal I/O operations shouldn't be allowed.

    Signed-off-by: Alan Stern
    Signed-off-by: Greg Kroah-Hartman

    Alan Stern
     
  • This patch starts making some serious changes to the UHCI driver.
    There's a set of private states for the root hub, and the internal
    routines for suspending and resuming work completely differently, with
    transitions based on the new states. Now the driver distinguishes
    between a privately auto-stopped state and a publicly suspended state,
    and it will properly suspend controllers with broken resume-detect
    interrupts instead of resetting them.

    Signed-off-by: Alan Stern
    Signed-off-by: Greg Kroah-Hartman

    Alan Stern
     
  • This patch makes a few small improvements in the UHCI driver. Some
    code is moved between different source files and a more useful pointer
    is passed to a callback routine.

    Signed-off-by: Alan Stern
    Signed-off-by: Greg Kroah-Hartman

    Alan Stern
     

17 Apr, 2005

1 commit

  • Initial git repository build. I'm not bothering with the full history,
    even though we have it. We can create a separate "historical" git
    archive of that later if we want to, and in the meantime it's about
    3.2GB when imported into git - space that would just make the early
    git days unnecessarily complicated, when we don't have a lot of good
    infrastructure for it.

    Let it rip!

    Linus Torvalds