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linux/drivers/input/mouse/lifebook.c
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

168 lines
4.3 KiB
C

/*
* Fujitsu B-series Lifebook PS/2 TouchScreen driver
*
* Copyright (c) 2005 Vojtech Pavlik <vojtech@suse.cz>
* Copyright (c) 2005 Kenan Esau <kenan.esau@conan.de>
*
* TouchScreen detection, absolute mode setting and packet layout is taken from
* Harald Hoyer's description of the device.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 as published by
* the Free Software Foundation.
*/
#include <linux/input.h>
#include <linux/serio.h>
#include <linux/libps2.h>
#include <linux/dmi.h>
#include "psmouse.h"
#include "lifebook.h"
static struct dmi_system_id lifebook_dmi_table[] = {
{
.ident = "LifeBook B",
.matches = {
DMI_MATCH(DMI_PRODUCT_NAME, "LifeBook B Series"),
},
},
{
.ident = "Lifebook B",
.matches = {
DMI_MATCH(DMI_PRODUCT_NAME, "LIFEBOOK B Series"),
},
},
{
.ident = "Lifebook B213x/B2150",
.matches = {
DMI_MATCH(DMI_PRODUCT_NAME, "LifeBook B2131/B2133/B2150"),
},
},
{
.ident = "Zephyr",
.matches = {
DMI_MATCH(DMI_PRODUCT_NAME, "ZEPHYR"),
},
},
{
.ident = "CF-18",
.matches = {
DMI_MATCH(DMI_PRODUCT_NAME, "CF-18"),
},
},
{
.ident = "Lifebook B142",
.matches = {
DMI_MATCH(DMI_PRODUCT_NAME, "LifeBook B142"),
},
},
{ }
};
static psmouse_ret_t lifebook_process_byte(struct psmouse *psmouse)
{
unsigned char *packet = psmouse->packet;
struct input_dev *dev = psmouse->dev;
if (psmouse->pktcnt != 3)
return PSMOUSE_GOOD_DATA;
/* calculate X and Y */
if ((packet[0] & 0x08) == 0x00) {
input_report_abs(dev, ABS_X,
(packet[1] | ((packet[0] & 0x30) << 4)));
input_report_abs(dev, ABS_Y,
1024 - (packet[2] | ((packet[0] & 0xC0) << 2)));
} else {
input_report_rel(dev, REL_X,
((packet[0] & 0x10) ? packet[1] - 256 : packet[1]));
input_report_rel(dev, REL_Y,
-(int)((packet[0] & 0x20) ? packet[2] - 256 : packet[2]));
}
input_report_key(dev, BTN_LEFT, packet[0] & 0x01);
input_report_key(dev, BTN_RIGHT, packet[0] & 0x02);
input_report_key(dev, BTN_TOUCH, packet[0] & 0x04);
input_sync(dev);
return PSMOUSE_FULL_PACKET;
}
static int lifebook_absolute_mode(struct psmouse *psmouse)
{
struct ps2dev *ps2dev = &psmouse->ps2dev;
unsigned char param;
if (psmouse_reset(psmouse))
return -1;
/*
Enable absolute output -- ps2_command fails always but if
you leave this call out the touchsreen will never send
absolute coordinates
*/
param = 0x07;
ps2_command(ps2dev, &param, PSMOUSE_CMD_SETRES);
return 0;
}
static void lifebook_set_resolution(struct psmouse *psmouse, unsigned int resolution)
{
static const unsigned char params[] = { 0, 1, 2, 2, 3 };
unsigned char p;
if (resolution == 0 || resolution > 400)
resolution = 400;
p = params[resolution / 100];
ps2_command(&psmouse->ps2dev, &p, PSMOUSE_CMD_SETRES);
psmouse->resolution = 50 << p;
}
static void lifebook_disconnect(struct psmouse *psmouse)
{
psmouse_reset(psmouse);
}
int lifebook_detect(struct psmouse *psmouse, int set_properties)
{
if (!dmi_check_system(lifebook_dmi_table))
return -1;
if (set_properties) {
psmouse->vendor = "Fujitsu";
psmouse->name = "Lifebook TouchScreen";
}
return 0;
}
int lifebook_init(struct psmouse *psmouse)
{
struct input_dev *input_dev = psmouse->dev;
if (lifebook_absolute_mode(psmouse))
return -1;
input_dev->evbit[0] = BIT(EV_ABS) | BIT(EV_KEY) | BIT(EV_REL);
input_dev->keybit[LONG(BTN_LEFT)] = BIT(BTN_LEFT) | BIT(BTN_MIDDLE) | BIT(BTN_RIGHT);
input_dev->keybit[LONG(BTN_TOUCH)] = BIT(BTN_TOUCH);
input_dev->relbit[0] = BIT(REL_X) | BIT(REL_Y);
input_set_abs_params(input_dev, ABS_X, 0, 1024, 0, 0);
input_set_abs_params(input_dev, ABS_Y, 0, 1024, 0, 0);
psmouse->protocol_handler = lifebook_process_byte;
psmouse->set_resolution = lifebook_set_resolution;
psmouse->disconnect = lifebook_disconnect;
psmouse->reconnect = lifebook_absolute_mode;
psmouse->pktsize = 3;
return 0;
}