linux/drivers/input/mouse/vsxxxaa.c
Dmitry Torokhov 4db1f47c29 Input: vsxxxaa - fix code dropping bytes from queue
I believe the intent of the code was to drop oldest bytes from the queue,
not the latest if we drop one byte and both latest and some oldest of we
are dropping more than one.

Acked-by: Jan-Benedict Glaw <jbglaw@lug-owl.de>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
2014-10-28 10:33:48 -07:00

551 lines
14 KiB
C

/*
* Driver for DEC VSXXX-AA mouse (hockey-puck mouse, ball or two rollers)
* DEC VSXXX-GA mouse (rectangular mouse, with ball)
* DEC VSXXX-AB tablet (digitizer with hair cross or stylus)
*
* Copyright (C) 2003-2004 by Jan-Benedict Glaw <jbglaw@lug-owl.de>
*
* The packet format was initially taken from a patch to GPM which is (C) 2001
* by Karsten Merker <merker@linuxtag.org>
* and Maciej W. Rozycki <macro@ds2.pg.gda.pl>
* Later on, I had access to the device's documentation (referenced below).
*/
/*
* 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
/*
* Building an adaptor to DE9 / DB25 RS232
* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
*
* DISCLAIMER: Use this description AT YOUR OWN RISK! I'll not pay for
* anything if you break your mouse, your computer or whatever!
*
* In theory, this mouse is a simple RS232 device. In practice, it has got
* a quite uncommon plug and the requirement to additionally get a power
* supply at +5V and -12V.
*
* If you look at the socket/jack (_not_ at the plug), we use this pin
* numbering:
* _______
* / 7 6 5 \
* | 4 --- 3 |
* \ 2 1 /
* -------
*
* DEC socket DE9 DB25 Note
* 1 (GND) 5 7 -
* 2 (RxD) 2 3 -
* 3 (TxD) 3 2 -
* 4 (-12V) - - Somewhere from the PSU. At ATX, it's
* the thin blue wire at pin 12 of the
* ATX power connector. Only required for
* VSXXX-AA/-GA mice.
* 5 (+5V) - - PSU (red wires of ATX power connector
* on pin 4, 6, 19 or 20) or HDD power
* connector (also red wire).
* 6 (+12V) - - HDD power connector, yellow wire. Only
* required for VSXXX-AB digitizer.
* 7 (dev. avail.) - - The mouse shorts this one to pin 1.
* This way, the host computer can detect
* the mouse. To use it with the adaptor,
* simply don't connect this pin.
*
* So to get a working adaptor, you need to connect the mouse with three
* wires to a RS232 port and two or three additional wires for +5V, +12V and
* -12V to the PSU.
*
* Flow specification for the link is 4800, 8o1.
*
* The mice and tablet are described in "VCB02 Video Subsystem - Technical
* Manual", DEC EK-104AA-TM-001. You'll find it at MANX, a search engine
* specific for DEC documentation. Try
* http://www.vt100.net/manx/details?pn=EK-104AA-TM-001;id=21;cp=1
*/
#include <linux/delay.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/interrupt.h>
#include <linux/input.h>
#include <linux/serio.h>
#define DRIVER_DESC "Driver for DEC VSXXX-AA and -GA mice and VSXXX-AB tablet"
MODULE_AUTHOR("Jan-Benedict Glaw <jbglaw@lug-owl.de>");
MODULE_DESCRIPTION(DRIVER_DESC);
MODULE_LICENSE("GPL");
#undef VSXXXAA_DEBUG
#ifdef VSXXXAA_DEBUG
#define DBG(x...) printk(x)
#else
#define DBG(x...) do {} while (0)
#endif
#define VSXXXAA_INTRO_MASK 0x80
#define VSXXXAA_INTRO_HEAD 0x80
#define IS_HDR_BYTE(x) \
(((x) & VSXXXAA_INTRO_MASK) == VSXXXAA_INTRO_HEAD)
#define VSXXXAA_PACKET_MASK 0xe0
#define VSXXXAA_PACKET_REL 0x80
#define VSXXXAA_PACKET_ABS 0xc0
#define VSXXXAA_PACKET_POR 0xa0
#define MATCH_PACKET_TYPE(data, type) \
(((data) & VSXXXAA_PACKET_MASK) == (type))
struct vsxxxaa {
struct input_dev *dev;
struct serio *serio;
#define BUFLEN 15 /* At least 5 is needed for a full tablet packet */
unsigned char buf[BUFLEN];
unsigned char count;
unsigned char version;
unsigned char country;
unsigned char type;
char name[64];
char phys[32];
};
static void vsxxxaa_drop_bytes(struct vsxxxaa *mouse, int num)
{
if (num >= mouse->count) {
mouse->count = 0;
} else {
memmove(mouse->buf, mouse->buf + num, BUFLEN - num);
mouse->count -= num;
}
}
static void vsxxxaa_queue_byte(struct vsxxxaa *mouse, unsigned char byte)
{
if (mouse->count == BUFLEN) {
printk(KERN_ERR "%s on %s: Dropping a byte of full buffer.\n",
mouse->name, mouse->phys);
vsxxxaa_drop_bytes(mouse, 1);
}
DBG(KERN_INFO "Queueing byte 0x%02x\n", byte);
mouse->buf[mouse->count++] = byte;
}
static void vsxxxaa_detection_done(struct vsxxxaa *mouse)
{
switch (mouse->type) {
case 0x02:
strlcpy(mouse->name, "DEC VSXXX-AA/-GA mouse",
sizeof(mouse->name));
break;
case 0x04:
strlcpy(mouse->name, "DEC VSXXX-AB digitizer",
sizeof(mouse->name));
break;
default:
snprintf(mouse->name, sizeof(mouse->name),
"unknown DEC pointer device (type = 0x%02x)",
mouse->type);
break;
}
printk(KERN_INFO
"Found %s version 0x%02x from country 0x%02x on port %s\n",
mouse->name, mouse->version, mouse->country, mouse->phys);
}
/*
* Returns number of bytes to be dropped, 0 if packet is okay.
*/
static int vsxxxaa_check_packet(struct vsxxxaa *mouse, int packet_len)
{
int i;
/* First byte must be a header byte */
if (!IS_HDR_BYTE(mouse->buf[0])) {
DBG("vsck: len=%d, 1st=0x%02x\n", packet_len, mouse->buf[0]);
return 1;
}
/* Check all following bytes */
for (i = 1; i < packet_len; i++) {
if (IS_HDR_BYTE(mouse->buf[i])) {
printk(KERN_ERR
"Need to drop %d bytes of a broken packet.\n",
i - 1);
DBG(KERN_INFO "check: len=%d, b[%d]=0x%02x\n",
packet_len, i, mouse->buf[i]);
return i - 1;
}
}
return 0;
}
static inline int vsxxxaa_smells_like_packet(struct vsxxxaa *mouse,
unsigned char type, size_t len)
{
return mouse->count >= len && MATCH_PACKET_TYPE(mouse->buf[0], type);
}
static void vsxxxaa_handle_REL_packet(struct vsxxxaa *mouse)
{
struct input_dev *dev = mouse->dev;
unsigned char *buf = mouse->buf;
int left, middle, right;
int dx, dy;
/*
* Check for normal stream packets. This is three bytes,
* with the first byte's 3 MSB set to 100.
*
* [0]: 1 0 0 SignX SignY Left Middle Right
* [1]: 0 dx dx dx dx dx dx dx
* [2]: 0 dy dy dy dy dy dy dy
*/
/*
* Low 7 bit of byte 1 are abs(dx), bit 7 is
* 0, bit 4 of byte 0 is direction.
*/
dx = buf[1] & 0x7f;
dx *= ((buf[0] >> 4) & 0x01) ? 1 : -1;
/*
* Low 7 bit of byte 2 are abs(dy), bit 7 is
* 0, bit 3 of byte 0 is direction.
*/
dy = buf[2] & 0x7f;
dy *= ((buf[0] >> 3) & 0x01) ? -1 : 1;
/*
* Get button state. It's the low three bits
* (for three buttons) of byte 0.
*/
left = buf[0] & 0x04;
middle = buf[0] & 0x02;
right = buf[0] & 0x01;
vsxxxaa_drop_bytes(mouse, 3);
DBG(KERN_INFO "%s on %s: dx=%d, dy=%d, buttons=%s%s%s\n",
mouse->name, mouse->phys, dx, dy,
left ? "L" : "l", middle ? "M" : "m", right ? "R" : "r");
/*
* Report what we've found so far...
*/
input_report_key(dev, BTN_LEFT, left);
input_report_key(dev, BTN_MIDDLE, middle);
input_report_key(dev, BTN_RIGHT, right);
input_report_key(dev, BTN_TOUCH, 0);
input_report_rel(dev, REL_X, dx);
input_report_rel(dev, REL_Y, dy);
input_sync(dev);
}
static void vsxxxaa_handle_ABS_packet(struct vsxxxaa *mouse)
{
struct input_dev *dev = mouse->dev;
unsigned char *buf = mouse->buf;
int left, middle, right, touch;
int x, y;
/*
* Tablet position / button packet
*
* [0]: 1 1 0 B4 B3 B2 B1 Pr
* [1]: 0 0 X5 X4 X3 X2 X1 X0
* [2]: 0 0 X11 X10 X9 X8 X7 X6
* [3]: 0 0 Y5 Y4 Y3 Y2 Y1 Y0
* [4]: 0 0 Y11 Y10 Y9 Y8 Y7 Y6
*/
/*
* Get X/Y position. Y axis needs to be inverted since VSXXX-AB
* counts down->top while monitor counts top->bottom.
*/
x = ((buf[2] & 0x3f) << 6) | (buf[1] & 0x3f);
y = ((buf[4] & 0x3f) << 6) | (buf[3] & 0x3f);
y = 1023 - y;
/*
* Get button state. It's bits <4..1> of byte 0.
*/
left = buf[0] & 0x02;
middle = buf[0] & 0x04;
right = buf[0] & 0x08;
touch = buf[0] & 0x10;
vsxxxaa_drop_bytes(mouse, 5);
DBG(KERN_INFO "%s on %s: x=%d, y=%d, buttons=%s%s%s%s\n",
mouse->name, mouse->phys, x, y,
left ? "L" : "l", middle ? "M" : "m",
right ? "R" : "r", touch ? "T" : "t");
/*
* Report what we've found so far...
*/
input_report_key(dev, BTN_LEFT, left);
input_report_key(dev, BTN_MIDDLE, middle);
input_report_key(dev, BTN_RIGHT, right);
input_report_key(dev, BTN_TOUCH, touch);
input_report_abs(dev, ABS_X, x);
input_report_abs(dev, ABS_Y, y);
input_sync(dev);
}
static void vsxxxaa_handle_POR_packet(struct vsxxxaa *mouse)
{
struct input_dev *dev = mouse->dev;
unsigned char *buf = mouse->buf;
int left, middle, right;
unsigned char error;
/*
* Check for Power-On-Reset packets. These are sent out
* after plugging the mouse in, or when explicitly
* requested by sending 'T'.
*
* [0]: 1 0 1 0 R3 R2 R1 R0
* [1]: 0 M2 M1 M0 D3 D2 D1 D0
* [2]: 0 E6 E5 E4 E3 E2 E1 E0
* [3]: 0 0 0 0 0 Left Middle Right
*
* M: manufacturer location code
* R: revision code
* E: Error code. If it's in the range of 0x00..0x1f, only some
* minor problem occurred. Errors >= 0x20 are considered bad
* and the device may not work properly...
* D: <0010> == mouse, <0100> == tablet
*/
mouse->version = buf[0] & 0x0f;
mouse->country = (buf[1] >> 4) & 0x07;
mouse->type = buf[1] & 0x0f;
error = buf[2] & 0x7f;
/*
* Get button state. It's the low three bits
* (for three buttons) of byte 0. Maybe even the bit <3>
* has some meaning if a tablet is attached.
*/
left = buf[0] & 0x04;
middle = buf[0] & 0x02;
right = buf[0] & 0x01;
vsxxxaa_drop_bytes(mouse, 4);
vsxxxaa_detection_done(mouse);
if (error <= 0x1f) {
/* No (serious) error. Report buttons */
input_report_key(dev, BTN_LEFT, left);
input_report_key(dev, BTN_MIDDLE, middle);
input_report_key(dev, BTN_RIGHT, right);
input_report_key(dev, BTN_TOUCH, 0);
input_sync(dev);
if (error != 0)
printk(KERN_INFO "Your %s on %s reports error=0x%02x\n",
mouse->name, mouse->phys, error);
}
/*
* If the mouse was hot-plugged, we need to force differential mode
* now... However, give it a second to recover from it's reset.
*/
printk(KERN_NOTICE
"%s on %s: Forcing standard packet format, "
"incremental streaming mode and 72 samples/sec\n",
mouse->name, mouse->phys);
serio_write(mouse->serio, 'S'); /* Standard format */
mdelay(50);
serio_write(mouse->serio, 'R'); /* Incremental */
mdelay(50);
serio_write(mouse->serio, 'L'); /* 72 samples/sec */
}
static void vsxxxaa_parse_buffer(struct vsxxxaa *mouse)
{
unsigned char *buf = mouse->buf;
int stray_bytes;
/*
* Parse buffer to death...
*/
do {
/*
* Out of sync? Throw away what we don't understand. Each
* packet starts with a byte whose bit 7 is set. Unhandled
* packets (ie. which we don't know about or simply b0rk3d
* data...) will get shifted out of the buffer after some
* activity on the mouse.
*/
while (mouse->count > 0 && !IS_HDR_BYTE(buf[0])) {
printk(KERN_ERR "%s on %s: Dropping a byte to regain "
"sync with mouse data stream...\n",
mouse->name, mouse->phys);
vsxxxaa_drop_bytes(mouse, 1);
}
/*
* Check for packets we know about.
*/
if (vsxxxaa_smells_like_packet(mouse, VSXXXAA_PACKET_REL, 3)) {
/* Check for broken packet */
stray_bytes = vsxxxaa_check_packet(mouse, 3);
if (!stray_bytes)
vsxxxaa_handle_REL_packet(mouse);
} else if (vsxxxaa_smells_like_packet(mouse,
VSXXXAA_PACKET_ABS, 5)) {
/* Check for broken packet */
stray_bytes = vsxxxaa_check_packet(mouse, 5);
if (!stray_bytes)
vsxxxaa_handle_ABS_packet(mouse);
} else if (vsxxxaa_smells_like_packet(mouse,
VSXXXAA_PACKET_POR, 4)) {
/* Check for broken packet */
stray_bytes = vsxxxaa_check_packet(mouse, 4);
if (!stray_bytes)
vsxxxaa_handle_POR_packet(mouse);
} else {
break; /* No REL, ABS or POR packet found */
}
if (stray_bytes > 0) {
printk(KERN_ERR "Dropping %d bytes now...\n",
stray_bytes);
vsxxxaa_drop_bytes(mouse, stray_bytes);
}
} while (1);
}
static irqreturn_t vsxxxaa_interrupt(struct serio *serio,
unsigned char data, unsigned int flags)
{
struct vsxxxaa *mouse = serio_get_drvdata(serio);
vsxxxaa_queue_byte(mouse, data);
vsxxxaa_parse_buffer(mouse);
return IRQ_HANDLED;
}
static void vsxxxaa_disconnect(struct serio *serio)
{
struct vsxxxaa *mouse = serio_get_drvdata(serio);
serio_close(serio);
serio_set_drvdata(serio, NULL);
input_unregister_device(mouse->dev);
kfree(mouse);
}
static int vsxxxaa_connect(struct serio *serio, struct serio_driver *drv)
{
struct vsxxxaa *mouse;
struct input_dev *input_dev;
int err = -ENOMEM;
mouse = kzalloc(sizeof(struct vsxxxaa), GFP_KERNEL);
input_dev = input_allocate_device();
if (!mouse || !input_dev)
goto fail1;
mouse->dev = input_dev;
mouse->serio = serio;
strlcat(mouse->name, "DEC VSXXX-AA/-GA mouse or VSXXX-AB digitizer",
sizeof(mouse->name));
snprintf(mouse->phys, sizeof(mouse->phys), "%s/input0", serio->phys);
input_dev->name = mouse->name;
input_dev->phys = mouse->phys;
input_dev->id.bustype = BUS_RS232;
input_dev->dev.parent = &serio->dev;
__set_bit(EV_KEY, input_dev->evbit); /* We have buttons */
__set_bit(EV_REL, input_dev->evbit);
__set_bit(EV_ABS, input_dev->evbit);
__set_bit(BTN_LEFT, input_dev->keybit); /* We have 3 buttons */
__set_bit(BTN_MIDDLE, input_dev->keybit);
__set_bit(BTN_RIGHT, input_dev->keybit);
__set_bit(BTN_TOUCH, input_dev->keybit); /* ...and Tablet */
__set_bit(REL_X, input_dev->relbit);
__set_bit(REL_Y, input_dev->relbit);
input_set_abs_params(input_dev, ABS_X, 0, 1023, 0, 0);
input_set_abs_params(input_dev, ABS_Y, 0, 1023, 0, 0);
serio_set_drvdata(serio, mouse);
err = serio_open(serio, drv);
if (err)
goto fail2;
/*
* Request selftest. Standard packet format and differential
* mode will be requested after the device ID'ed successfully.
*/
serio_write(serio, 'T'); /* Test */
err = input_register_device(input_dev);
if (err)
goto fail3;
return 0;
fail3: serio_close(serio);
fail2: serio_set_drvdata(serio, NULL);
fail1: input_free_device(input_dev);
kfree(mouse);
return err;
}
static struct serio_device_id vsxxaa_serio_ids[] = {
{
.type = SERIO_RS232,
.proto = SERIO_VSXXXAA,
.id = SERIO_ANY,
.extra = SERIO_ANY,
},
{ 0 }
};
MODULE_DEVICE_TABLE(serio, vsxxaa_serio_ids);
static struct serio_driver vsxxxaa_drv = {
.driver = {
.name = "vsxxxaa",
},
.description = DRIVER_DESC,
.id_table = vsxxaa_serio_ids,
.connect = vsxxxaa_connect,
.interrupt = vsxxxaa_interrupt,
.disconnect = vsxxxaa_disconnect,
};
module_serio_driver(vsxxxaa_drv);