Commit Graph

13 Commits

Author SHA1 Message Date
David Howells
7d12e780e0 IRQ: Maintain regs pointer globally rather than passing to IRQ handlers
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)
2006-10-05 15:10:12 +01:00
Mark Assad
77dc2db6d1 [PATCH] itmtouch: fix inverted flag to indicate touch location correctly, correct white space
There is a bug in the current version of the itmtouch USB touchscreen
driver.  The if statment that checks if pressure is being applied to the
touch screen is now missing a ! (not), so events are no longer being
reported correctly.

The original source code for this line was as follows:

	#define UCP(x) ((unsigned char*)(x))
	#define UCOM(x,y,z) ((UCP((x)->transfer_buffer)[y]) & (z))

	...
	if (!UCOM(urb, 7, 0x20)) {

And was cleaned to:

	unsigned char *data = urb->transfer_buffer;
	....
	 if (data[7] & 0x20) {

(note the lack of '!')

This has been tested on an LG L1510BF and an LG1510SF touch screen.

Signed-off-by: Mark Assad <massad@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-04 19:44:36 -07:00
Pete Zaitcev
38e2bfc94e USB: Dealias -110 code (more complete)
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 <zaitcev@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-09-27 11:59:00 -07:00
Jörn Engel
6ab3d5624e Remove obsolete #include <linux/config.h>
Signed-off-by: Jörn Engel <joern@wohnheim.fh-wedel.de>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-06-30 19:25:36 +02:00
David Brownell
ae0dadcf0f [PATCH] USB: move <linux/usb_input.h> to <linux/usb/input.h>
Move <linux/usb_input.h> to <linux/usb/input.h> and remove some
redundant includes.

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-06-21 15:04:18 -07:00
Greg Kroah-Hartman
75318d2d7c [PATCH] USB: remove .owner field from struct usb_driver
It is no longer needed, so let's remove it, saving a bit of memory.

Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-01-04 13:48:34 -08:00
Greg Kroah-Hartman
654f31189e [PATCH] USB: move CONFIG_USB_DEBUG checks into the Makefile
This lets us remove a lot of code in the drivers that were all checking
the same thing.  It also found some bugs in a few of the drivers, which
has been fixed up.

Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-17 11:29:55 -08:00
Dmitry Torokhov
c5b7c7c395 [PATCH] drivers/usb/input: convert to dynamic input_dev allocation
Input: convert drivers/iusb/input to dynamic input_dev allocation

This is required for input_dev sysfs integration

Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-10-28 09:52:52 -07:00
Pekka Enberg
7b842b6e37 [PATCH] USB: convert kcalloc to kzalloc
This patch converts kcalloc(1, ...) calls to use the new kzalloc() function.

Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-07 16:57:46 -07:00
Dmitry Torokhov
16a334c0de Input: introduce usb_to_input_id() to uniformly produce
struct input_id for USB input devices.

Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
2005-06-30 00:49:08 -05:00
Dmitry Torokhov
65cde54b8b Input: remove user counters from drivers/usb/input since input
core takes care of calling open and close methods only
       when needed.

Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
2005-05-29 02:29:38 -05:00
Dmitry Torokhov
05f091ab4c Input: whitespace fixes in drivers/usb/input
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
2005-05-29 02:29:01 -05:00
Hans-Christian Egtvedt
8608471262 Input: Add driver for ITM Touch USB touchscreens.
From: Hans-Christian Egtvedt <hc@mivu.no>
Signed-off-by: Vojtech Pavlik <vojtech@suse.cz>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
2005-05-29 02:27:45 -05:00