Doug / smarc-fsl-linux-kernel

28 Nov, 2006

1 commit

07 Oct, 2006

2 commits

05 Oct, 2006

1 commit

  • 7d12e780e   IRQ: Maintain regs pointer globally rather than passing to IRQ handlers ... Browse Code »

    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
     

01 Oct, 2006

1 commit

28 Sep, 2006

1 commit

  • 38e2bfc94   USB: Dealias -110 code (more complete) ... Browse Code »

    The purpose of this patch is to split off the case when a device does
    not reply on the lower level (which is reported by HC hardware), and
    a case when the device accepted the request, but does not reply at
    upper level. This redefinition allows to diagnose issues easier,
    without asking the user if the -110 happened "immediately".

    The usbmon splits such cases already thanks to its timestamp, but
    it's not always available.

    I adjusted all drivers which I found affected (by searching for "urb").
    Out of tree drivers may suffer a little bit, but I do not expect much
    breakage. At worst they may print a few messages.

    Signed-off-by: Pete Zaitcev
    Signed-off-by: Greg Kroah-Hartman

    Pete Zaitcev
     

23 Sep, 2006

7 commits

03 Aug, 2006

1 commit

29 Jun, 2006

1 commit

  • e217e30c3   [ALSA] usb-audio support for Turtle Beach Roadie ... Browse Code »

    From: Sam Revitch Recently a Turtle Beach Audio Advantage Roadie device ended up in my
    possession. It seems to work with the snd-usb-audio driver, but only
    using the headphone jack in 2-channel mode. The device has a DIN
    connector carrying six more channels that are otherwise silent.
    C-Media has freely available documentation for the CM106 chip around
    which this device is based, and enabling 8-channel output, or
    6-channel output with the headphone jack following the front pair is a
    matter of setting one of its registers.
    Attached is a patch to try to enable 5.1 output mode at probe time.
    It seems to work correctly with my device. There is quite list of
    other configurables for this device that might deserve controls.

    Signed-off-by: Takashi Iwai
    Signed-off-by: Jaroslav Kysela

    Sam Revitch
     

23 Jun, 2006

7 commits

28 Apr, 2006

1 commit

31 Mar, 2006

1 commit

29 Mar, 2006

1 commit

22 Mar, 2006

15 commits