android_kernel_xiaomi_sm7250/drivers/usb/input/itmtouch.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

272 lines
7.6 KiB
C

/******************************************************************************
* itmtouch.c -- Driver for ITM touchscreen panel
*
* 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 Chris Collins <xfire-itmtouch@xware.cx>.
*
* Kudos to ITM for providing me with the datasheet for the panel,
* even though it was a day later than I had finished writing this
* driver.
*
* It has meant that I've been able to correct my interpretation of the
* protocol packets however.
*
* CC -- 2003/9/29
*
* History
* 1.0 & 1.1 2003 (CC) vojtech@suse.cz
* Original version for 2.4.x kernels
*
* 1.2 02/03/2005 (HCE) hc@mivu.no
* Complete rewrite to support Linux 2.6.10, thanks to mtouchusb.c for hints.
* Unfortunately no calibration support at this time.
*
* 1.2.1 09/03/2005 (HCE) hc@mivu.no
* Code cleanup and adjusting syntax to start matching kernel standards
*
* 1.2.2 10/05/2006 (MJA) massad@gmail.com
* Flag for detecting if the screen was being touch was incorrectly
* inverted, so no touch events were being detected.
*
*****************************************************************************/
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/usb/input.h>
/* only an 8 byte buffer necessary for a single packet */
#define ITM_BUFSIZE 8
#define PATH_SIZE 64
#define USB_VENDOR_ID_ITMINC 0x0403
#define USB_PRODUCT_ID_TOUCHPANEL 0xf9e9
#define DRIVER_AUTHOR "Hans-Christian Egtvedt <hc@mivu.no>"
#define DRIVER_VERSION "v1.2.2"
#define DRIVER_DESC "USB ITM Inc Touch Panel Driver"
#define DRIVER_LICENSE "GPL"
MODULE_AUTHOR( DRIVER_AUTHOR );
MODULE_DESCRIPTION( DRIVER_DESC );
MODULE_LICENSE( DRIVER_LICENSE );
struct itmtouch_dev {
struct usb_device *usbdev; /* usb device */
struct input_dev *inputdev; /* input device */
struct urb *readurb; /* urb */
char rbuf[ITM_BUFSIZE]; /* data */
int users;
char name[128];
char phys[64];
};
static struct usb_device_id itmtouch_ids [] = {
{ USB_DEVICE(USB_VENDOR_ID_ITMINC, USB_PRODUCT_ID_TOUCHPANEL) },
{ }
};
static void itmtouch_irq(struct urb *urb)
{
struct itmtouch_dev *itmtouch = urb->context;
unsigned char *data = urb->transfer_buffer;
struct input_dev *dev = itmtouch->inputdev;
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;
}
/* if pressure has been released, then don't report X/Y */
if (!(data[7] & 0x20)) {
input_report_abs(dev, ABS_X, (data[0] & 0x1F) << 7 | (data[3] & 0x7F));
input_report_abs(dev, ABS_Y, (data[1] & 0x1F) << 7 | (data[4] & 0x7F));
}
input_report_abs(dev, ABS_PRESSURE, (data[2] & 1) << 7 | (data[5] & 0x7F));
input_report_key(dev, BTN_TOUCH, ~data[7] & 0x20);
input_sync(dev);
exit:
retval = usb_submit_urb (urb, GFP_ATOMIC);
if (retval)
printk(KERN_ERR "%s - usb_submit_urb failed with result: %d",
__FUNCTION__, retval);
}
static int itmtouch_open(struct input_dev *input)
{
struct itmtouch_dev *itmtouch = input->private;
itmtouch->readurb->dev = itmtouch->usbdev;
if (usb_submit_urb(itmtouch->readurb, GFP_KERNEL))
return -EIO;
return 0;
}
static void itmtouch_close(struct input_dev *input)
{
struct itmtouch_dev *itmtouch = input->private;
usb_kill_urb(itmtouch->readurb);
}
static int itmtouch_probe(struct usb_interface *intf, const struct usb_device_id *id)
{
struct itmtouch_dev *itmtouch;
struct input_dev *input_dev;
struct usb_host_interface *interface;
struct usb_endpoint_descriptor *endpoint;
struct usb_device *udev = interface_to_usbdev(intf);
unsigned int pipe;
unsigned int maxp;
interface = intf->cur_altsetting;
endpoint = &interface->endpoint[0].desc;
itmtouch = kzalloc(sizeof(struct itmtouch_dev), GFP_KERNEL);
input_dev = input_allocate_device();
if (!itmtouch || !input_dev) {
err("%s - Out of memory.", __FUNCTION__);
goto fail;
}
itmtouch->usbdev = udev;
itmtouch->inputdev = input_dev;
if (udev->manufacturer)
strlcpy(itmtouch->name, udev->manufacturer, sizeof(itmtouch->name));
if (udev->product) {
if (udev->manufacturer)
strlcat(itmtouch->name, " ", sizeof(itmtouch->name));
strlcat(itmtouch->name, udev->product, sizeof(itmtouch->name));
}
if (!strlen(itmtouch->name))
sprintf(itmtouch->name, "USB ITM touchscreen");
usb_make_path(udev, itmtouch->phys, sizeof(itmtouch->phys));
strlcpy(itmtouch->phys, "/input0", sizeof(itmtouch->phys));
input_dev->name = itmtouch->name;
input_dev->phys = itmtouch->phys;
usb_to_input_id(udev, &input_dev->id);
input_dev->cdev.dev = &intf->dev;
input_dev->private = itmtouch;
input_dev->open = itmtouch_open;
input_dev->close = itmtouch_close;
input_dev->evbit[0] = BIT(EV_KEY) | BIT(EV_ABS);
input_dev->absbit[0] = BIT(ABS_X) | BIT(ABS_Y) | BIT(ABS_PRESSURE);
input_dev->keybit[LONG(BTN_TOUCH)] = BIT(BTN_TOUCH);
/* device limits */
/* as specified by the ITM datasheet, X and Y are 12bit,
* Z (pressure) is 8 bit. However, the fields are defined up
* to 14 bits for future possible expansion.
*/
input_set_abs_params(input_dev, ABS_X, 0, 0x0FFF, 2, 0);
input_set_abs_params(input_dev, ABS_Y, 0, 0x0FFF, 2, 0);
input_set_abs_params(input_dev, ABS_PRESSURE, 0, 0xFF, 2, 0);
/* initialise the URB so we can read from the transport stream */
pipe = usb_rcvintpipe(itmtouch->usbdev, endpoint->bEndpointAddress);
maxp = usb_maxpacket(udev, pipe, usb_pipeout(pipe));
if (maxp > ITM_BUFSIZE)
maxp = ITM_BUFSIZE;
itmtouch->readurb = usb_alloc_urb(0, GFP_KERNEL);
if (!itmtouch->readurb) {
dbg("%s - usb_alloc_urb failed: itmtouch->readurb", __FUNCTION__);
goto fail;
}
usb_fill_int_urb(itmtouch->readurb, itmtouch->usbdev, pipe, itmtouch->rbuf,
maxp, itmtouch_irq, itmtouch, endpoint->bInterval);
input_register_device(itmtouch->inputdev);
usb_set_intfdata(intf, itmtouch);
return 0;
fail: input_free_device(input_dev);
kfree(itmtouch);
return -ENOMEM;
}
static void itmtouch_disconnect(struct usb_interface *intf)
{
struct itmtouch_dev *itmtouch = usb_get_intfdata(intf);
usb_set_intfdata(intf, NULL);
if (itmtouch) {
input_unregister_device(itmtouch->inputdev);
usb_kill_urb(itmtouch->readurb);
usb_free_urb(itmtouch->readurb);
kfree(itmtouch);
}
}
MODULE_DEVICE_TABLE(usb, itmtouch_ids);
static struct usb_driver itmtouch_driver = {
.name = "itmtouch",
.probe = itmtouch_probe,
.disconnect = itmtouch_disconnect,
.id_table = itmtouch_ids,
};
static int __init itmtouch_init(void)
{
info(DRIVER_DESC " " DRIVER_VERSION);
info(DRIVER_AUTHOR);
return usb_register(&itmtouch_driver);
}
static void __exit itmtouch_exit(void)
{
usb_deregister(&itmtouch_driver);
}
module_init(itmtouch_init);
module_exit(itmtouch_exit);