kevin/linux
1
Fork 0
Code
78001e3d75
linux/drivers/usb/input/keyspan_remote.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

590 lines
15 KiB
C
Raw Blame History

/*
* keyspan_remote: USB driver for the Keyspan DMR
*
* Copyright (C) 2005 Zymeta Corporation - Michael Downey (downey@zymeta.com)
*
* 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, version 2.
*
* This driver has been put together with the support of Innosys, Inc.
* and Keyspan, Inc the manufacturers of the Keyspan USB DMR product.
*/
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/usb/input.h>
#define DRIVER_VERSION "v0.1"
#define DRIVER_AUTHOR "Michael Downey <downey@zymeta.com>"
#define DRIVER_DESC "Driver for the USB Keyspan remote control."
#define DRIVER_LICENSE "GPL"
/* Parameters that can be passed to the driver. */
static int debug;
module_param(debug, int, 0444);
MODULE_PARM_DESC(debug, "Enable extra debug messages and information");
/* Vendor and product ids */
#define USB_KEYSPAN_VENDOR_ID 0x06CD
#define USB_KEYSPAN_PRODUCT_UIA11 0x0202
/* Defines for converting the data from the remote. */
#define ZERO 0x18
#define ZERO_MASK 0x1F /* 5 bits for a 0 */
#define ONE 0x3C
#define ONE_MASK 0x3F /* 6 bits for a 1 */
#define SYNC 0x3F80
#define SYNC_MASK 0x3FFF /* 14 bits for a SYNC sequence */
#define STOP 0x00
#define STOP_MASK 0x1F /* 5 bits for the STOP sequence */
#define GAP 0xFF
#define RECV_SIZE 8 /* The UIA-11 type have a 8 byte limit. */
/* table of devices that work with this driver */
static struct usb_device_id keyspan_table[] = {
{ USB_DEVICE(USB_KEYSPAN_VENDOR_ID, USB_KEYSPAN_PRODUCT_UIA11) },
{ } /* Terminating entry */
};
/* Structure to store all the real stuff that a remote sends to us. */
struct keyspan_message {
u16 system;
u8 button;
u8 toggle;
};
/* Structure used for all the bit testing magic needed to be done. */
struct bit_tester {
u32 tester;
int len;
int pos;
int bits_left;
u8 buffer[32];
};
/* Structure to hold all of our driver specific stuff */
struct usb_keyspan {
char name[128];
char phys[64];
struct usb_device* udev;
struct input_dev *input;
struct usb_interface* interface;
struct usb_endpoint_descriptor* in_endpoint;
struct urb* irq_urb;
int open;
dma_addr_t in_dma;
unsigned char* in_buffer;
/* variables used to parse messages from remote. */
struct bit_tester data;
int stage;
int toggle;
};
/*
* Table that maps the 31 possible keycodes to input keys.
* Currently there are 15 and 17 button models so RESERVED codes
* are blank areas in the mapping.
*/
static const int keyspan_key_table[] = {
KEY_RESERVED, /* 0 is just a place holder. */
KEY_RESERVED,
KEY_STOP,
KEY_PLAYCD,
KEY_RESERVED,
KEY_PREVIOUSSONG,
KEY_REWIND,
KEY_FORWARD,
KEY_NEXTSONG,
KEY_RESERVED,
KEY_RESERVED,
KEY_RESERVED,
KEY_PAUSE,
KEY_VOLUMEUP,
KEY_RESERVED,
KEY_RESERVED,
KEY_RESERVED,
KEY_VOLUMEDOWN,
KEY_RESERVED,
KEY_UP,
KEY_RESERVED,
KEY_MUTE,
KEY_LEFT,
KEY_ENTER,
KEY_RIGHT,
KEY_RESERVED,
KEY_RESERVED,
KEY_DOWN,
KEY_RESERVED,
KEY_KPASTERISK,
KEY_RESERVED,
KEY_MENU
};
static struct usb_driver keyspan_driver;
/*
* Debug routine that prints out what we've received from the remote.
*/
static void keyspan_print(struct usb_keyspan* dev) /*unsigned char* data)*/
{
char codes[4 * RECV_SIZE];
int i;
for (i = 0; i < RECV_SIZE; i++)
snprintf(codes + i * 3, 4, "%02x ", dev->in_buffer[i]);
dev_info(&dev->udev->dev, "%s\n", codes);
}
/*
* Routine that manages the bit_tester structure. It makes sure that there are
* at least bits_needed bits loaded into the tester.
*/
static int keyspan_load_tester(struct usb_keyspan* dev, int bits_needed)
{
if (dev->data.bits_left >= bits_needed)
return 0;
/*
* Somehow we've missed the last message. The message will be repeated
* though so it's not too big a deal
*/
if (dev->data.pos >= dev->data.len) {
dev_dbg(&dev->udev->dev,
"%s - Error ran out of data. pos: %d, len: %d\n",
__FUNCTION__, dev->data.pos, dev->data.len);
return -1;
}
/* Load as much as we can into the tester. */
while ((dev->data.bits_left + 7 < (sizeof(dev->data.tester) * 8)) &&
(dev->data.pos < dev->data.len)) {
dev->data.tester += (dev->data.buffer[dev->data.pos++] << dev->data.bits_left);
dev->data.bits_left += 8;
}
return 0;
}
/*
* Routine that handles all the logic needed to parse out the message from the remote.
*/
static void keyspan_check_data(struct usb_keyspan *remote)
{
int i;
int found = 0;
struct keyspan_message message;
switch(remote->stage) {
case 0:
/*
* In stage 0 we want to find the start of a message. The remote sends a 0xFF as filler.
* So the first byte that isn't a FF should be the start of a new message.
*/
for (i = 0; i < RECV_SIZE && remote->in_buffer[i] == GAP; ++i);
if (i < RECV_SIZE) {
memcpy(remote->data.buffer, remote->in_buffer, RECV_SIZE);
remote->data.len = RECV_SIZE;
remote->data.pos = 0;
remote->data.tester = 0;
remote->data.bits_left = 0;
remote->stage = 1;
}
break;
case 1:
/*
* Stage 1 we should have 16 bytes and should be able to detect a
* SYNC. The SYNC is 14 bits, 7 0's and then 7 1's.
*/
memcpy(remote->data.buffer + remote->data.len, remote->in_buffer, RECV_SIZE);
remote->data.len += RECV_SIZE;
found = 0;
while ((remote->data.bits_left >= 14 || remote->data.pos < remote->data.len) && !found) {
for (i = 0; i < 8; ++i) {
if (keyspan_load_tester(remote, 14) != 0) {
remote->stage = 0;
return;
}
if ((remote->data.tester & SYNC_MASK) == SYNC) {
remote->data.tester = remote->data.tester >> 14;
remote->data.bits_left -= 14;
found = 1;
break;
} else {
remote->data.tester = remote->data.tester >> 1;
--remote->data.bits_left;
}
}
}
if (!found) {
remote->stage = 0;
remote->data.len = 0;
} else {
remote->stage = 2;
}
break;
case 2:
/*
* Stage 2 we should have 24 bytes which will be enough for a full
* message. We need to parse out the system code, button code,
* toggle code, and stop.
*/
memcpy(remote->data.buffer + remote->data.len, remote->in_buffer, RECV_SIZE);
remote->data.len += RECV_SIZE;
message.system = 0;
for (i = 0; i < 9; i++) {
keyspan_load_tester(remote, 6);
if ((remote->data.tester & ZERO_MASK) == ZERO) {
message.system = message.system << 1;
remote->data.tester = remote->data.tester >> 5;
remote->data.bits_left -= 5;
} else if ((remote->data.tester & ONE_MASK) == ONE) {
message.system = (message.system << 1) + 1;
remote->data.tester = remote->data.tester >> 6;
remote->data.bits_left -= 6;
} else {
err("%s - Unknown sequence found in system data.\n", __FUNCTION__);
remote->stage = 0;
return;
}
}
message.button = 0;
for (i = 0; i < 5; i++) {
keyspan_load_tester(remote, 6);
if ((remote->data.tester & ZERO_MASK) == ZERO) {
message.button = message.button << 1;
remote->data.tester = remote->data.tester >> 5;
remote->data.bits_left -= 5;
} else if ((remote->data.tester & ONE_MASK) == ONE) {
message.button = (message.button << 1) + 1;
remote->data.tester = remote->data.tester >> 6;
remote->data.bits_left -= 6;
} else {
err("%s - Unknown sequence found in button data.\n", __FUNCTION__);
remote->stage = 0;
return;
}
}
keyspan_load_tester(remote, 6);
if ((remote->data.tester & ZERO_MASK) == ZERO) {
message.toggle = 0;
remote->data.tester = remote->data.tester >> 5;
remote->data.bits_left -= 5;
} else if ((remote->data.tester & ONE_MASK) == ONE) {
message.toggle = 1;
remote->data.tester = remote->data.tester >> 6;
remote->data.bits_left -= 6;
} else {
err("%s - Error in message, invalid toggle.\n", __FUNCTION__);
remote->stage = 0;
return;
}
keyspan_load_tester(remote, 5);
if ((remote->data.tester & STOP_MASK) == STOP) {
remote->data.tester = remote->data.tester >> 5;
remote->data.bits_left -= 5;
} else {
err("Bad message recieved, no stop bit found.\n");
}
dev_dbg(&remote->udev->dev,
"%s found valid message: system: %d, button: %d, toggle: %d\n",
__FUNCTION__, message.system, message.button, message.toggle);
if (message.toggle != remote->toggle) {
input_report_key(remote->input, keyspan_key_table[message.button], 1);
input_report_key(remote->input, keyspan_key_table[message.button], 0);
input_sync(remote->input);
remote->toggle = message.toggle;
}
remote->stage = 0;
break;
}
}
/*
* Routine for sending all the initialization messages to the remote.
*/
static int keyspan_setup(struct usb_device* dev)
{
int retval = 0;
retval = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
0x11, 0x40, 0x5601, 0x0, NULL, 0, 0);
if (retval) {
dev_dbg(&dev->dev, "%s - failed to set bit rate due to error: %d\n",
__FUNCTION__, retval);
return(retval);
}
retval = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
0x44, 0x40, 0x0, 0x0, NULL, 0, 0);
if (retval) {
dev_dbg(&dev->dev, "%s - failed to set resume sensitivity due to error: %d\n",
__FUNCTION__, retval);
return(retval);
}
retval = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
0x22, 0x40, 0x0, 0x0, NULL, 0, 0);
if (retval) {
dev_dbg(&dev->dev, "%s - failed to turn receive on due to error: %d\n",
__FUNCTION__, retval);
return(retval);
}
dev_dbg(&dev->dev, "%s - Setup complete.\n", __FUNCTION__);
return(retval);
}
/*
* Routine used to handle a new message that has come in.
*/
static void keyspan_irq_recv(struct urb *urb)
{
struct usb_keyspan *dev = urb->context;
int retval;
/* Check our status in case we need to bail out early. */
switch (urb->status) {
case 0:
break;
/* Device went away so don't keep trying to read from it. */
case -ECONNRESET:
case -ENOENT:
case -ESHUTDOWN:
return;
default:
goto resubmit;
break;
}
if (debug)
keyspan_print(dev);
keyspan_check_data(dev);
resubmit:
retval = usb_submit_urb(urb, GFP_ATOMIC);
if (retval)
err ("%s - usb_submit_urb failed with result: %d", __FUNCTION__, retval);
}
static int keyspan_open(struct input_dev *dev)
{
struct usb_keyspan *remote = dev->private;
remote->irq_urb->dev = remote->udev;
if (usb_submit_urb(remote->irq_urb, GFP_KERNEL))
return -EIO;
return 0;
}
static void keyspan_close(struct input_dev *dev)
{
struct usb_keyspan *remote = dev->private;
usb_kill_urb(remote->irq_urb);
}
static struct usb_endpoint_descriptor *keyspan_get_in_endpoint(struct usb_host_interface *iface)
{
struct usb_endpoint_descriptor *endpoint;
int i;
for (i = 0; i < iface->desc.bNumEndpoints; ++i) {
endpoint = &iface->endpoint[i].desc;
if (usb_endpoint_is_int_in(endpoint)) {
/* we found our interrupt in endpoint */
return endpoint;
}
}
return NULL;
}
/*
* Routine that sets up the driver to handle a specific USB device detected on the bus.
*/
static int keyspan_probe(struct usb_interface *interface, const struct usb_device_id *id)
{
struct usb_device *udev = interface_to_usbdev(interface);
struct usb_endpoint_descriptor *endpoint;
struct usb_keyspan *remote;
struct input_dev *input_dev;
int i, retval;
endpoint = keyspan_get_in_endpoint(interface->cur_altsetting);
if (!endpoint)
return -ENODEV;
remote = kzalloc(sizeof(*remote), GFP_KERNEL);
input_dev = input_allocate_device();
if (!remote || !input_dev) {
retval = -ENOMEM;
goto fail1;
}
remote->udev = udev;
remote->input = input_dev;
remote->interface = interface;
remote->in_endpoint = endpoint;
remote->toggle = -1; /* Set to -1 so we will always not match the toggle from the first remote message. */
remote->in_buffer = usb_buffer_alloc(udev, RECV_SIZE, SLAB_ATOMIC, &remote->in_dma);
if (!remote->in_buffer) {
retval = -ENOMEM;
goto fail1;
}
remote->irq_urb = usb_alloc_urb(0, GFP_KERNEL);
if (!remote->irq_urb) {
retval = -ENOMEM;
goto fail2;
}
retval = keyspan_setup(udev);
if (retval) {
retval = -ENODEV;
goto fail3;
}
if (udev->manufacturer)
strlcpy(remote->name, udev->manufacturer, sizeof(remote->name));
if (udev->product) {
if (udev->manufacturer)
strlcat(remote->name, " ", sizeof(remote->name));
strlcat(remote->name, udev->product, sizeof(remote->name));
}
if (!strlen(remote->name))
snprintf(remote->name, sizeof(remote->name),
"USB Keyspan Remote %04x:%04x",
le16_to_cpu(udev->descriptor.idVendor),
le16_to_cpu(udev->descriptor.idProduct));
usb_make_path(udev, remote->phys, sizeof(remote->phys));
strlcat(remote->phys, "/input0", sizeof(remote->phys));
input_dev->name = remote->name;
input_dev->phys = remote->phys;
usb_to_input_id(udev, &input_dev->id);
input_dev->cdev.dev = &interface->dev;
input_dev->evbit[0] = BIT(EV_KEY); /* We will only report KEY events. */
for (i = 0; i < ARRAY_SIZE(keyspan_key_table); i++)
if (keyspan_key_table[i] != KEY_RESERVED)
set_bit(keyspan_key_table[i], input_dev->keybit);
input_dev->private = remote;
input_dev->open = keyspan_open;
input_dev->close = keyspan_close;
/*
* Initialize the URB to access the device. The urb gets sent to the device in keyspan_open()
*/
usb_fill_int_urb(remote->irq_urb,
remote->udev, usb_rcvintpipe(remote->udev, remote->in_endpoint->bEndpointAddress),
remote->in_buffer, RECV_SIZE, keyspan_irq_recv, remote,
remote->in_endpoint->bInterval);
remote->irq_urb->transfer_dma = remote->in_dma;
remote->irq_urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
/* we can register the device now, as it is ready */
input_register_device(remote->input);
/* save our data pointer in this interface device */
usb_set_intfdata(interface, remote);
return 0;
fail3: usb_free_urb(remote->irq_urb);
fail2: usb_buffer_free(udev, RECV_SIZE, remote->in_buffer, remote->in_dma);
fail1: kfree(remote);
input_free_device(input_dev);
return retval;
}
/*
* Routine called when a device is disconnected from the USB.
*/
static void keyspan_disconnect(struct usb_interface *interface)
{
struct usb_keyspan *remote;
remote = usb_get_intfdata(interface);
usb_set_intfdata(interface, NULL);
if (remote) { /* We have a valid driver structure so clean up everything we allocated. */
input_unregister_device(remote->input);
usb_kill_urb(remote->irq_urb);
usb_free_urb(remote->irq_urb);
usb_buffer_free(remote->udev, RECV_SIZE, remote->in_buffer, remote->in_dma);
kfree(remote);
}
}
/*
* Standard driver set up sections
*/
static struct usb_driver keyspan_driver =
{
.name = "keyspan_remote",
.probe = keyspan_probe,
.disconnect = keyspan_disconnect,
.id_table = keyspan_table
};
static int __init usb_keyspan_init(void)
{
int result;
/* register this driver with the USB subsystem */
result = usb_register(&keyspan_driver);
if (result)
err("usb_register failed. Error number %d\n", result);
return result;
}
static void __exit usb_keyspan_exit(void)
{
/* deregister this driver with the USB subsystem */
usb_deregister(&keyspan_driver);
}
module_init(usb_keyspan_init);
module_exit(usb_keyspan_exit);
MODULE_DEVICE_TABLE(usb, keyspan_table);
MODULE_AUTHOR(DRIVER_AUTHOR);
MODULE_DESCRIPTION(DRIVER_DESC);
MODULE_LICENSE(DRIVER_LICENSE);
View Git Blame Copy Permalink