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 <dhowells@redhat.com>
(cherry picked from 1b16e7ac850969f38b375e511e3fa2f474a33867 commit)
Added TLV-read support to snd-usb-audio driver for passing
the volume dB scale information to user-space.
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Jaroslav Kysela <perex@suse.cz>
This patch rewrites the remote control code to use a table for
the peculiarities of the various SB models, and adds support
for a third model.
Signed-off-by: Raimonds Cicans <ray@vardes.lv>
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Test the volume of usb audio whether actually it works and adjusts
the resolution value according to it.
Some USB audio devices report a lower resolution than it reacts.
The only possible check is to write and read a volume value.
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Modules: USB generic driver
We may leak 'namelist' in sound/usb/usbmixer.c::parse_audio_selector_unit()
Signed-off-by: Jesper Juhl <jesper.juhl@gmail.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Modules: USB generic driver
snd_ctl_add() kfree's the kcontrol already if we fail there,
so this driver is currently doing a double kfree.
Coverity bug #959
Signed-off-by: Dave Jones <davej@redhat.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
`gcc -W' likes to complain if the static keyword is not at the beginning of
the declaration. This patch fixes all remaining occurrences of "inline
static" up with "static inline" in the entire kernel tree (140 occurrences in
47 files).
While making this change I came across a few lines with trailing whitespace
that I also fixed up, I have also added or removed a blank line or two here
and there, but there are no functional changes in the patch.
Signed-off-by: Jesper Juhl <juhl-lkml@dif.dk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Timer Midlevel,ALSA sequencer,ALSA<-OSS sequencer,Digigram VX core
I2C tea6330t,GUS Library,VIA82xx driver,VIA82xx-modem driver
CA0106 driver,CS46xx driver,EMU10K1/EMU10K2 driver,YMFPCI driver
Digigram VX Pocket driver,Common EMU synth,USB generic driver,USB USX2Y
Checking a pointer for NULL before calling kfree() on it is redundant,
kfree() deals with NULL pointers just fine.
This patch removes such checks from sound/
This patch also makes another, but closely related, change.
It avoids casting pointers about to be kfree()'ed.
Signed-off-by: Jesper Juhl <juhl-lkml@dif.dk>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
USB generic driver
This patch adds a proc file for the SB Audigy 2 NX which shows the
connection status of the various jacks. Unfortunately, no SPDIF input
frequency (yet).
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
USB generic driver
The ioctls for LIRC compatibility can be removed because the
infrastructure and detection stuff is better done in user space.
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
USB generic driver
Adds mixer controls for the CMSS/Dolby Digital/Power LEDs
on the SB Audigy 2 NX.
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
USB generic driver
Add ioctls to the Sound Blaster remote control hwdep device so that it
can be used with LIRC.
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
USB generic driver
Extension units can have type 0, so do not ignore them when constructing
mixer controls.
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
USB generic driver
Cache the decoded values of idVendor/idProduct to get rid of most of
those ugly le16_to_cpu() calls.
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
ALSA Core,USB generic driver
Add an hwdep interface that supports reading remote control data from
Sound Blaster Extigy and Audigy 2 NX devices.
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
USB generic driver
Add support for the optional status interrupt endpoint in audio control
interfaces, and translate USB status notifications into ALSA mixer
control notifications.
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
USB generic driver
Move all data related to audio control interfaces into a separate struct
local to usbmixer.c.
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
USB generic driver
Unit/terminal IDs are 8-bit integers, so the unitbitmap
variable does not need to be bigger than 256 bits.
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
USB generic driver
Add a mechanism to specify source names of selector units,
and add such names for the SB Audigy 2 NX.
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
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!
