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)
Revert bttv-driver.c from video_device_create_file() to use
class_device_create_file() again. video_device_create_file() is only
available when V4L1 is on.
Proper error checking is added for failure of class_device_create_file().
Will print error message and unroll partially created sysfs entries.
Signed-off-by: Trent Piepho <xyzzy@speakeasy.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
Check __must_check warnings for class_device_register and class_device_create_file
video_device_create_file was declared as a void, but instead should
return the int value of class_device_create_file.
Move the check from bttv-driver.c into v4l2-dev.h, because all other
callers of video_device_create_file must also be checked.
Replace the call to class_device_create_file in videodev.c with
video_device_create_file, as defined in v4l2-dev.h, so that the
return value of class_device_create_file will be checked.
Check the return value of class_device_register in videodev.c and
pvrusb2-sysfs.c
Signed-off-by: Michael Krufky <mkrufky@linuxtv.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
This is needed if we wish to change the size of the resource structures.
Based on an original patch from Vivek Goyal <vgoyal@in.ibm.com>
Cc: Vivek Goyal <vgoyal@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Renamed various msp3400 routing defines to be more consistent and less
confusing. Esp. the MSP_DSP_OUT defines were confusing since it is really
a DSP input.
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
- msp3400c did not detect the second carrier, thus being always mono.
- properly mute the msp3400c while detecting the carrier.
- fix checks on the presence of scart2/3 inputs and scart 2 output.
- implement proper audio mode fallbacks for msp3400c/d, identical to the
way msp3400g works.
- MODE_STEREO no longer produces dual languages when set for a bilingual
transmission, instead it falls back to LANG1. Use LANG1_LANG2 to hear
both languages of a bilingual transmission. This is much more intuitive
for the user and is in accordance with the preferred usage in the v4l2
specification.
- bttv tried to implement v4l2 calls with v4l1 calls to the i2c devices,
completely mangling the audmode/rxsubchans handling. v4l2 calls now do
v4l2 calls to the i2c devices.
- fixed broken i2c_vidiocschan in bttv.
- add start/end lines to LOG_STATUS.
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
Add a new audio mode V4L2_TUNER_MODE_LANG1_LANG2 (used by VIDIOC_G/S_TUNER).
This mode allows the user to select both languages of a bilingual transmission,
one language on the left, one on the right audio channel. If there is no
bilingual transmission, or it is not supported, then this mode should act like
V4L2_TUNER_MODE_STEREO.
This mode is introduced for PVR-like drivers where it is useful to be able to
record both languages of a bilingual broadcast.
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
- implement VIDIOC_INT_S_AUDIO_ROUTING for msp3400 and tvaudio
- use the new command in bttv, pvrusb2 and em28xx.
- remove the now obsolete MSP_SET_MATRIX from msp3400 (yeah!)
- remove the obsolete VIDIOC_S_AUDIO from msp3400.
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
Cleanup audio input handling in bttv and tvaudio:
- inputs were specified that were never used
- mute was handled as a special input which led to confusing code
- confusing naming made it difficult to see if the setting was for
i2c or gpio.
The old audiochip.h input names moved to tvaudio.h. Currently this
is used both by tvaudio and msp3400 until the msp3400 implements the
new msp3400-specific inputs.
Detect in bttv the tvaudio and msp3400 i2c clients and use these
client pointers to set the inputs directly instead of broadcasting the
command.
Removed AUDC_SET_INPUT. Now replaced by VIDIOC_S_AUDIO. This will be
replaced again later by the new ROUTING commands.
Removed VIDIOC_G_AUDIO implementations in i2c drivers: this command is
a user level command and not to be used internally. It wasn't called at
all anyway.
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
- Missing a Makefile for bt8xx
- rds.h were at wrong directory, since it is a global header for an internal
interface
- tda7432 and tda9875 were dependent from bttv.h
- bttv.h were holding i2c addresses
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
