There were many places in the driver which had long sequences of constant
register initializations. These were done with one function call per
register. The register address and value were immediate values in the
function calls.
This is very inefficient, as each register and value take twice the space
when they are code, as each includes a push instruction to put it on
the stack. There there is the overhead, both size and time, for a
function call for each register. It's also quite a few lines of C code
to do this.
The patch creates a function that writes multiple registers from a list,
and a macro that makes it easy to construct a such a list as a const
static local to send to the function.
This gets rid of quite a bit of C code, and shrinks the driver by around
8k, while at the same time being more efficient.
Acked-by: Luca Risolia <luca.risolia@studio.unibo.it>
Signed-off-by: Trent Piepho <xyzzy@speakeasy.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
@ Don't assume that SOF headers can't cross packets boundaries
@ Fix compression quality selection
+ Add support for MI-0360 image sensor
* Documentation updates
@ Fix sysfs
@ MI0343 rewritten
* HV7131R color fixes and add new ABLC control
* Rename the archive from "sn9c102" to "sn9c1xx"
* fix typos
* better support for TAS5110D
@ fix OV7630 wrong colors
@ Don't return an error if no input buffers are enqueued yet on VIDIOC_STREAMON
* Add informations about colorspaces
* More appropriate error codes in case of failure of some system calls
* More precise hardware detection
* Add more informations about supported hardware in the documentation
+ More supported devices
+ Add support for HV7131R image sensor
Signed-off-by: Luca Risolia <luca.risolia@studio.unibo.it>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
- Add support for SN9C105 and SN9C120
- Add some more USB device identifiers
- Add support for OV7660
- Implement audio ioctl's and VIDIOC_ENUM_FRAMESIZES
- Add preliminary support for 0x0c45/0x6007
- Documentation updates
- Generic improvements
Signed-off-by: Luca Risolia <luca.risolia@studio.unibo.it>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
Many struct file_operations in the kernel can be "const". Marking them const
moves these to the .rodata section, which avoids false sharing with potential
dirty data. In addition it'll catch accidental writes at compile time to
these shared resources.
[akpm@sdl.org: dvb fix]
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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)
V4L1 API is depreciated and should be removed soon from kernel. This patch
adds two new options, one to disable V4L1 drivers, and another to disable
V4L1 compat module. This way, it would be easy to check what still depends
on V4L1 stuff, allowing also to test if app works fine with V4L2 only support.
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
- Move documentation for usb v4l devices from
Documentation/usb to Documentation/video4linux.
- Removed trailing whitespace.
- Update Kconfig help text links to reflect the new file locations.
Signed-off-by: Michael Krufky <mkrufky@linuxtv.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
Because of historic reasons, there are two separate directories with
V4L stuff. Most drivers are located at driver/media/video. However, some
code for USB Webcams were inserted under drivers/usb/media.
This makes difficult for module authors to know were things should be.
Also, makes Kconfig menu confusing for normal users.
This patch moves all V4L content under drivers/usb/media to
drivers/media/video, and fixes Kconfig/Makefile entries.
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>