kernel-ark/drivers/usb/input/mtouchusb.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

333 lines
10 KiB
C

/******************************************************************************
* mtouchusb.c -- Driver for Microtouch (Now 3M) USB Touchscreens
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation; either version 2 of the
* License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*
* Based upon original work by Radoslaw Garbacz (usb-support@ite.pl)
* (http://freshmeat.net/projects/3mtouchscreendriver)
*
* History
*
* 0.3 & 0.4 2002 (TEJ) tejohnson@yahoo.com
* Updated to 2.4.18, then 2.4.19
* Old version still relied on stealing a minor
*
* 0.5 02/26/2004 (TEJ) tejohnson@yahoo.com
* Complete rewrite using Linux Input in 2.6.3
* Unfortunately no calibration support at this time
*
* 1.4 04/25/2004 (TEJ) tejohnson@yahoo.com
* Changed reset from standard USB dev reset to vendor reset
* Changed data sent to host from compensated to raw coordinates
* Eliminated vendor/product module params
* Performed multiple successful tests with an EXII-5010UC
*
* 1.5 02/27/2005 ddstreet@ieee.org
* Added module parameter to select raw or hw-calibrated coordinate reporting
*
*****************************************************************************/
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/usb/input.h>
#define MTOUCHUSB_MIN_XC 0x0
#define MTOUCHUSB_MAX_RAW_XC 0x4000
#define MTOUCHUSB_MAX_CALIB_XC 0xffff
#define MTOUCHUSB_XC_FUZZ 0x0
#define MTOUCHUSB_XC_FLAT 0x0
#define MTOUCHUSB_MIN_YC 0x0
#define MTOUCHUSB_MAX_RAW_YC 0x4000
#define MTOUCHUSB_MAX_CALIB_YC 0xffff
#define MTOUCHUSB_YC_FUZZ 0x0
#define MTOUCHUSB_YC_FLAT 0x0
#define MTOUCHUSB_ASYNC_REPORT 1
#define MTOUCHUSB_RESET 7
#define MTOUCHUSB_REPORT_DATA_SIZE 11
#define MTOUCHUSB_REQ_CTRLLR_ID 10
#define MTOUCHUSB_GET_RAW_XC(data) (data[8]<<8 | data[7])
#define MTOUCHUSB_GET_CALIB_XC(data) (data[4]<<8 | data[3])
#define MTOUCHUSB_GET_RAW_YC(data) (data[10]<<8 | data[9])
#define MTOUCHUSB_GET_CALIB_YC(data) (data[6]<<8 | data[5])
#define MTOUCHUSB_GET_XC(data) (raw_coordinates ? \
MTOUCHUSB_GET_RAW_XC(data) : \
MTOUCHUSB_GET_CALIB_XC(data))
#define MTOUCHUSB_GET_YC(data) (raw_coordinates ? \
MTOUCHUSB_GET_RAW_YC(data) : \
MTOUCHUSB_GET_CALIB_YC(data))
#define MTOUCHUSB_GET_TOUCHED(data) ((data[2] & 0x40) ? 1:0)
#define DRIVER_VERSION "v1.5"
#define DRIVER_AUTHOR "Todd E. Johnson, tejohnson@yahoo.com"
#define DRIVER_DESC "3M USB Touchscreen Driver"
#define DRIVER_LICENSE "GPL"
static int raw_coordinates = 1;
module_param(raw_coordinates, bool, S_IRUGO | S_IWUSR);
MODULE_PARM_DESC(raw_coordinates, "report raw coordinate values (y, default) or hardware-calibrated coordinate values (n)");
struct mtouch_usb {
unsigned char *data;
dma_addr_t data_dma;
struct urb *irq;
struct usb_device *udev;
struct input_dev *input;
char name[128];
char phys[64];
};
static struct usb_device_id mtouchusb_devices[] = {
{ USB_DEVICE(0x0596, 0x0001) },
{ }
};
static void mtouchusb_irq(struct urb *urb)
{
struct mtouch_usb *mtouch = urb->context;
int retval;
switch (urb->status) {
case 0:
/* success */
break;
case -ETIME:
/* this urb is timing out */
dbg("%s - urb timed out - was the device unplugged?",
__FUNCTION__);
return;
case -ECONNRESET:
case -ENOENT:
case -ESHUTDOWN:
/* this urb is terminated, clean up */
dbg("%s - urb shutting down with status: %d",
__FUNCTION__, urb->status);
return;
default:
dbg("%s - nonzero urb status received: %d",
__FUNCTION__, urb->status);
goto exit;
}
input_report_key(mtouch->input, BTN_TOUCH,
MTOUCHUSB_GET_TOUCHED(mtouch->data));
input_report_abs(mtouch->input, ABS_X, MTOUCHUSB_GET_XC(mtouch->data));
input_report_abs(mtouch->input, ABS_Y,
(raw_coordinates ? MTOUCHUSB_MAX_RAW_YC : MTOUCHUSB_MAX_CALIB_YC)
- MTOUCHUSB_GET_YC(mtouch->data));
input_sync(mtouch->input);
exit:
retval = usb_submit_urb(urb, GFP_ATOMIC);
if (retval)
err("%s - usb_submit_urb failed with result: %d",
__FUNCTION__, retval);
}
static int mtouchusb_open(struct input_dev *input)
{
struct mtouch_usb *mtouch = input->private;
mtouch->irq->dev = mtouch->udev;
if (usb_submit_urb(mtouch->irq, GFP_ATOMIC))
return -EIO;
return 0;
}
static void mtouchusb_close(struct input_dev *input)
{
struct mtouch_usb *mtouch = input->private;
usb_kill_urb(mtouch->irq);
}
static int mtouchusb_alloc_buffers(struct usb_device *udev, struct mtouch_usb *mtouch)
{
dbg("%s - called", __FUNCTION__);
mtouch->data = usb_buffer_alloc(udev, MTOUCHUSB_REPORT_DATA_SIZE,
SLAB_ATOMIC, &mtouch->data_dma);
if (!mtouch->data)
return -1;
return 0;
}
static void mtouchusb_free_buffers(struct usb_device *udev, struct mtouch_usb *mtouch)
{
dbg("%s - called", __FUNCTION__);
if (mtouch->data)
usb_buffer_free(udev, MTOUCHUSB_REPORT_DATA_SIZE,
mtouch->data, mtouch->data_dma);
}
static int mtouchusb_probe(struct usb_interface *intf, const struct usb_device_id *id)
{
struct mtouch_usb *mtouch;
struct input_dev *input_dev;
struct usb_host_interface *interface;
struct usb_endpoint_descriptor *endpoint;
struct usb_device *udev = interface_to_usbdev(intf);
int nRet;
dbg("%s - called", __FUNCTION__);
dbg("%s - setting interface", __FUNCTION__);
interface = intf->cur_altsetting;
dbg("%s - setting endpoint", __FUNCTION__);
endpoint = &interface->endpoint[0].desc;
mtouch = kzalloc(sizeof(struct mtouch_usb), GFP_KERNEL);
input_dev = input_allocate_device();
if (!mtouch || !input_dev) {
err("%s - Out of memory.", __FUNCTION__);
goto fail1;
}
dbg("%s - allocating buffers", __FUNCTION__);
if (mtouchusb_alloc_buffers(udev, mtouch))
goto fail2;
mtouch->udev = udev;
mtouch->input = input_dev;
if (udev->manufacturer)
strlcpy(mtouch->name, udev->manufacturer, sizeof(mtouch->name));
if (udev->product) {
if (udev->manufacturer)
strlcat(mtouch->name, " ", sizeof(mtouch->name));
strlcat(mtouch->name, udev->product, sizeof(mtouch->name));
}
if (!strlen(mtouch->name))
snprintf(mtouch->name, sizeof(mtouch->name),
"USB Touchscreen %04x:%04x",
le16_to_cpu(udev->descriptor.idVendor),
le16_to_cpu(udev->descriptor.idProduct));
usb_make_path(udev, mtouch->phys, sizeof(mtouch->phys));
strlcpy(mtouch->phys, "/input0", sizeof(mtouch->phys));
input_dev->name = mtouch->name;
input_dev->phys = mtouch->phys;
usb_to_input_id(udev, &input_dev->id);
input_dev->cdev.dev = &intf->dev;
input_dev->private = mtouch;
input_dev->open = mtouchusb_open;
input_dev->close = mtouchusb_close;
input_dev->evbit[0] = BIT(EV_KEY) | BIT(EV_ABS);
input_dev->keybit[LONG(BTN_TOUCH)] = BIT(BTN_TOUCH);
input_set_abs_params(input_dev, ABS_X, MTOUCHUSB_MIN_XC,
raw_coordinates ? MTOUCHUSB_MAX_RAW_XC : MTOUCHUSB_MAX_CALIB_XC,
MTOUCHUSB_XC_FUZZ, MTOUCHUSB_XC_FLAT);
input_set_abs_params(input_dev, ABS_Y, MTOUCHUSB_MIN_YC,
raw_coordinates ? MTOUCHUSB_MAX_RAW_YC : MTOUCHUSB_MAX_CALIB_YC,
MTOUCHUSB_YC_FUZZ, MTOUCHUSB_YC_FLAT);
nRet = usb_control_msg(mtouch->udev, usb_rcvctrlpipe(udev, 0),
MTOUCHUSB_RESET,
USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
1, 0, NULL, 0, USB_CTRL_SET_TIMEOUT);
dbg("%s - usb_control_msg - MTOUCHUSB_RESET - bytes|err: %d",
__FUNCTION__, nRet);
dbg("%s - usb_alloc_urb: mtouch->irq", __FUNCTION__);
mtouch->irq = usb_alloc_urb(0, GFP_KERNEL);
if (!mtouch->irq) {
dbg("%s - usb_alloc_urb failed: mtouch->irq", __FUNCTION__);
goto fail2;
}
dbg("%s - usb_fill_int_urb", __FUNCTION__);
usb_fill_int_urb(mtouch->irq, mtouch->udev,
usb_rcvintpipe(mtouch->udev, 0x81),
mtouch->data, MTOUCHUSB_REPORT_DATA_SIZE,
mtouchusb_irq, mtouch, endpoint->bInterval);
dbg("%s - input_register_device", __FUNCTION__);
input_register_device(mtouch->input);
nRet = usb_control_msg(mtouch->udev, usb_rcvctrlpipe(udev, 0),
MTOUCHUSB_ASYNC_REPORT,
USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
1, 1, NULL, 0, USB_CTRL_SET_TIMEOUT);
dbg("%s - usb_control_msg - MTOUCHUSB_ASYNC_REPORT - bytes|err: %d",
__FUNCTION__, nRet);
usb_set_intfdata(intf, mtouch);
return 0;
fail2: mtouchusb_free_buffers(udev, mtouch);
fail1: input_free_device(input_dev);
kfree(mtouch);
return -ENOMEM;
}
static void mtouchusb_disconnect(struct usb_interface *intf)
{
struct mtouch_usb *mtouch = usb_get_intfdata(intf);
dbg("%s - called", __FUNCTION__);
usb_set_intfdata(intf, NULL);
if (mtouch) {
dbg("%s - mtouch is initialized, cleaning up", __FUNCTION__);
usb_kill_urb(mtouch->irq);
input_unregister_device(mtouch->input);
usb_free_urb(mtouch->irq);
mtouchusb_free_buffers(interface_to_usbdev(intf), mtouch);
kfree(mtouch);
}
}
MODULE_DEVICE_TABLE(usb, mtouchusb_devices);
static struct usb_driver mtouchusb_driver = {
.name = "mtouchusb",
.probe = mtouchusb_probe,
.disconnect = mtouchusb_disconnect,
.id_table = mtouchusb_devices,
};
static int __init mtouchusb_init(void)
{
dbg("%s - called", __FUNCTION__);
return usb_register(&mtouchusb_driver);
}
static void __exit mtouchusb_cleanup(void)
{
dbg("%s - called", __FUNCTION__);
usb_deregister(&mtouchusb_driver);
}
module_init(mtouchusb_init);
module_exit(mtouchusb_cleanup);
MODULE_AUTHOR(DRIVER_AUTHOR);
MODULE_DESCRIPTION(DRIVER_DESC);
MODULE_LICENSE("GPL");