[PATCH] USB: input/touchkitusb: handle multiple packets

Some versions of the controller seem to put multiple report packet into a
single urb. also it can happen that a packet is split across multiple urbs.
unpatched you get a jumpy cursor on some screens.
the patch does:
- handle multiple packets per urb
- handle packets split across multiple urb
- check packet type
- cleanups

Signed-off-by: Daniel Ritz <daniel.ritz@gmx.ch>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This commit is contained in:
Daniel Ritz 2005-11-27 22:23:38 +01:00 committed by Greg Kroah-Hartman
parent 8a4613f01f
commit 5d3202949c

View file

@ -1,7 +1,7 @@
/******************************************************************************
* touchkitusb.c -- Driver for eGalax TouchKit USB Touchscreens
*
* Copyright (C) 2004 by Daniel Ritz
* Copyright (C) 2004-2005 by Daniel Ritz <daniel.ritz@gmx.ch>
* Copyright (C) by Todd E. Johnson (mtouchusb.c)
*
* This program is free software; you can redistribute it and/or
@ -41,15 +41,13 @@
#define TOUCHKIT_MAX_YC 0x07ff
#define TOUCHKIT_YC_FUZZ 0x0
#define TOUCHKIT_YC_FLAT 0x0
#define TOUCHKIT_REPORT_DATA_SIZE 8
#define TOUCHKIT_REPORT_DATA_SIZE 16
#define TOUCHKIT_DOWN 0x01
#define TOUCHKIT_POINT_TOUCH 0x81
#define TOUCHKIT_POINT_NOTOUCH 0x80
#define TOUCHKIT_GET_TOUCHED(dat) ((((dat)[0]) & TOUCHKIT_DOWN) ? 1 : 0)
#define TOUCHKIT_GET_X(dat) (((dat)[3] << 7) | (dat)[4])
#define TOUCHKIT_GET_Y(dat) (((dat)[1] << 7) | (dat)[2])
#define TOUCHKIT_PKT_TYPE_MASK 0xFE
#define TOUCHKIT_PKT_TYPE_REPT 0x80
#define TOUCHKIT_PKT_TYPE_DIAG 0x0A
#define DRIVER_VERSION "v0.1"
#define DRIVER_AUTHOR "Daniel Ritz <daniel.ritz@gmx.ch>"
@ -62,6 +60,8 @@ MODULE_PARM_DESC(swap_xy, "If set X and Y axes are swapped.");
struct touchkit_usb {
unsigned char *data;
dma_addr_t data_dma;
char buffer[TOUCHKIT_REPORT_DATA_SIZE];
int buf_len;
struct urb *irq;
struct usb_device *udev;
struct input_dev *input;
@ -77,11 +77,128 @@ static struct usb_device_id touchkit_devices[] = {
{}
};
/* helpers to read the data */
static inline int touchkit_get_touched(char *data)
{
return (data[0] & TOUCHKIT_DOWN) ? 1 : 0;
}
static inline int touchkit_get_x(char *data)
{
return ((data[3] & 0x0F) << 7) | (data[4] & 0x7F);
}
static inline int touchkit_get_y(char *data)
{
return ((data[1] & 0x0F) << 7) | (data[2] & 0x7F);
}
/* processes one input packet. */
static void touchkit_process_pkt(struct touchkit_usb *touchkit,
struct pt_regs *regs, char *pkt)
{
int x, y;
/* only process report packets */
if ((pkt[0] & TOUCHKIT_PKT_TYPE_MASK) != TOUCHKIT_PKT_TYPE_REPT)
return;
if (swap_xy) {
y = touchkit_get_x(pkt);
x = touchkit_get_y(pkt);
} else {
x = touchkit_get_x(pkt);
y = touchkit_get_y(pkt);
}
input_regs(touchkit->input, regs);
input_report_key(touchkit->input, BTN_TOUCH, touchkit_get_touched(pkt));
input_report_abs(touchkit->input, ABS_X, x);
input_report_abs(touchkit->input, ABS_Y, y);
input_sync(touchkit->input);
}
static int touchkit_get_pkt_len(char *buf)
{
switch (buf[0] & TOUCHKIT_PKT_TYPE_MASK) {
case TOUCHKIT_PKT_TYPE_REPT:
return 5;
case TOUCHKIT_PKT_TYPE_DIAG:
return buf[1] + 2;
}
return 0;
}
static void touchkit_process(struct touchkit_usb *touchkit, int len,
struct pt_regs *regs)
{
char *buffer;
int pkt_len, buf_len, pos;
/* if the buffer contains data, append */
if (unlikely(touchkit->buf_len)) {
int tmp;
/* if only 1 byte in buffer, add another one to get length */
if (touchkit->buf_len == 1)
touchkit->buffer[1] = touchkit->data[0];
pkt_len = touchkit_get_pkt_len(touchkit->buffer);
/* unknown packet: drop everything */
if (!pkt_len)
return;
/* append, process */
tmp = pkt_len - touchkit->buf_len;
memcpy(touchkit->buffer + touchkit->buf_len, touchkit->data, tmp);
touchkit_process_pkt(touchkit, regs, touchkit->buffer);
buffer = touchkit->data + tmp;
buf_len = len - tmp;
} else {
buffer = touchkit->data;
buf_len = len;
}
/* only one byte left in buffer */
if (unlikely(buf_len == 1)) {
touchkit->buffer[0] = buffer[0];
touchkit->buf_len = 1;
return;
}
/* loop over the buffer */
pos = 0;
while (pos < buf_len) {
/* get packet len */
pkt_len = touchkit_get_pkt_len(buffer + pos);
/* unknown packet: drop everything */
if (unlikely(!pkt_len))
return;
/* full packet: process */
if (likely(pkt_len <= buf_len)) {
touchkit_process_pkt(touchkit, regs, buffer + pos);
} else {
/* incomplete packet: save in buffer */
memcpy(touchkit->buffer, buffer + pos, buf_len - pos);
touchkit->buf_len = buf_len - pos;
}
pos += pkt_len;
}
}
static void touchkit_irq(struct urb *urb, struct pt_regs *regs)
{
struct touchkit_usb *touchkit = urb->context;
int retval;
int x, y;
switch (urb->status) {
case 0:
@ -105,20 +222,7 @@ static void touchkit_irq(struct urb *urb, struct pt_regs *regs)
goto exit;
}
if (swap_xy) {
y = TOUCHKIT_GET_X(touchkit->data);
x = TOUCHKIT_GET_Y(touchkit->data);
} else {
x = TOUCHKIT_GET_X(touchkit->data);
y = TOUCHKIT_GET_Y(touchkit->data);
}
input_regs(touchkit->input, regs);
input_report_key(touchkit->input, BTN_TOUCH,
TOUCHKIT_GET_TOUCHED(touchkit->data));
input_report_abs(touchkit->input, ABS_X, x);
input_report_abs(touchkit->input, ABS_Y, y);
input_sync(touchkit->input);
touchkit_process(touchkit, urb->actual_length, regs);
exit:
retval = usb_submit_urb(urb, GFP_ATOMIC);