/* $OpenBSD: tpms.c,v 1.12 2007/06/14 10:11:16 mbalmer Exp $ */
/*
* Copyright (c) 2005, Johan Wallén
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above
* copyright notice, this list of conditions and the following
* disclaimer in the documentation and/or other materials provided
* with the distribution.
*
* 3. The name of the copyright holder may not be used to endorse or
* promote products derived from this software without specific
* prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDER "AS IS" AND ANY
* EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
* BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
/*
* The tpms driver provides support for the trackpad on new (post
* February 2005) Apple PowerBooks (and iBooks?) that are not standard
* USB HID mice.
*/
/*
* The protocol (that is, the interpretation of the data generated by
* the trackpad) is taken from the Linux appletouch driver version
* 0.08 by Johannes Berg, Stelian Pop and Frank Arnold. The method
* used to detect fingers on the trackpad is also taken from that
* driver.
*/
/*
* PROTOCOL:
*
* The driver transfers continuously 81 byte events. The last byte is
* 1 if the button is pressed, and is 0 otherwise. Of the remaining
* bytes, 26 + 16 = 42 are sensors detecting pressure in the X or
* horizontal, and Y or vertical directions, respectively. On 12 and
* 15 inch PowerBooks, only the 16 first sensors in the X-direction
* are used. In the X-direction, the sensors correspond to byte
* positions
*
* 2, 7, 12, 17, 22, 27, 32, 37, 4, 9, 14, 19, 24, 29, 34, 39, 42,
* 47, 52, 57, 62, 67, 72, 77, 44 and 49;
*
* in the Y direction, the sensors correspond to byte positions
*
* 1, 6, 11, 16, 21, 26, 31, 36, 3, 8, 13, 18, 23, 28, 33 and 38.
*
* The change in the sensor values over time is more interesting than
* their absolute values: if the pressure increases, we know that the
* finger has just moved there.
*
* We keep track of the previous sample (of sensor values in the X and
* Y directions) and the accumulated change for each sensor. When we
* receive a new sample, we add the difference of the new sensor value
* and the old value to the accumulated change. If the accumulator
* becomes negative, we set it to zero. The effect is that the
* accumulator is large for sensors whose pressure has recently
* increased. If there is little change in pressure (or if the
* pressure decreases), the accumulator drifts back to zero.
*
* Since there is some fluctuations, we ignore accumulator values
* below a threshold. The raw finger position is computed as a
* weighted average of the other sensors (the weights are the
* accumulated changes).
*
* For smoothing, we keep track of the previous raw finger position,
* and the virtual position reported to wsmouse. The new raw position
* is computed as a weighted average of the old raw position and the
* computed raw position. Since this still generates some noise, we
* compute a new virtual position as a weighted average of the previous
* virtual position and the new raw position. The weights are
* controlled by the raw change and a noise parameter. The position
* is reported as a relative position.
*/
/*
* TODO:
*
* Add support for other drivers of the same type.
*
* Add support for tapping and two-finger scrolling? The
* implementation already detects two fingers, so this should be
* relatively easy.
*
* Implement some of the mouse ioctls?
*
* Take care of the XXXs.
*
*/
#include <sys/param.h>
#include <sys/device.h>
#include <sys/errno.h>
#include <sys/ioctl.h>
#include <sys/systm.h>
#include <sys/tty.h>
#include <dev/usb/usb.h>
#include <dev/usb/usbdi.h>
#include <dev/usb/usbdevs.h>
#include <dev/usb/uhidev.h>
#include <dev/wscons/wsconsio.h>
#include <dev/wscons/wsmousevar.h>
/*
* Debugging output.
*/
/* XXX Should be redone, and its use should be added back. */
#ifdef TPMS_DEBUG
/*
* Print the error message (preceded by the driver and function)
* specified by the string literal fmt (followed by newline) if
* tpmsdebug is greater than n. The macro may only be used in the
* scope of sc, which must be castable to struct device *. There must
* be at least one vararg. Do not define TPMS_DEBUG on non-C99
* compilers.
*/
#define DPRINTFN(n, fmt, ...) \
do { \
if (tpmsdebug > (n)) \
logprintf("%s: %s: " fmt "\n", \
((struct device *) sc)->dv_xname, \
__func__, __VA_ARGS__); \
} while ( /* CONSTCOND */ 0)
int tpmsdebug = 0;
#endif /* TPMS_DEBUG */
/*
* Magic numbers.
*/
/* The amount of data transfered by the USB device. */
#define TPMS_DATA_LEN 81
/* The maximum number of sensors. */
#define TPMS_X_SENSORS 26
#define TPMS_Y_SENSORS 16
#define TPMS_SENSORS (TPMS_X_SENSORS + TPMS_Y_SENSORS)
/*
* Parameters for supported devices. For generality, these parameters
* can be different for each device. The meanings of the parameters
* are as follows.
*
* desc: A printable description used for dmesg output.
*
* noise: Amount of noise in the computed position. This controls
* how large a change must be to get reported, and how
* large enough changes are smoothed. A good value can
* probably only be found experimentally, but something around
* 16 seems suitable.
*
* product: The product ID of the trackpad.
*
*
* threshold: Accumulated changes less than this are ignored. A good
* value could be determined experimentally, but 5 is a
* reasonable guess.
*
* vendor: The vendor ID. Currently USB_VENDOR_APPLE for all devices.
*
* x_factor: Factor used in computations with X-coordinates. If the
* x-resolution of the display is x, this should be
* (x + 1) / (x_sensors - 1). Other values work fine, but
* then the aspect ratio is not necessarily kept.
*
* x_sensors: The number of sensors in the X-direction.
*
* y_factor: As x_factors, but for Y-coordinates.
*
* y_sensors: The number of sensors in the Y-direction.
*/
struct tpms_dev {
const char *descr; /* Description of the driver (for dmesg). */
int noise; /* Amount of noise in the computed position. */
int threshold; /* Changes less than this are ignored. */
int x_factor; /* Factor used in computation with X-coordinates. */
int x_sensors; /* The number of X-sensors. */
int y_factor; /* Factor used in computation with Y-coordinates. */
int y_sensors; /* The number of Y-sensors. */
uint16_t product; /* Product ID. */
uint16_t vendor; /* The vendor ID. */
};
/* Devices supported by this driver. */
static struct tpms_dev tpms_devices[] =
{
#define POWERBOOK_TOUCHPAD(inches, prod, x_fact, x_sens, y_fact) \
{ \
.descr = #inches " inch PowerBook Trackpad", \
.vendor = USB_VENDOR_APPLE, \
.product = (prod), \
.noise = 16, \
.threshold = 5, \
.x_factor = (x_fact), \
.x_sensors = (x_sens), \
.y_factor = (y_fact), \
.y_sensors = 16 \
}
/* 12 inch PowerBooks */
POWERBOOK_TOUCHPAD(12, 0x030a, 69, 16, 52), /* XXX Not tested. */
/* 14 inch iBook G4 */
POWERBOOK_TOUCHPAD(14, 0x030b, 69, 16, 52),
/* 15 inch PowerBooks */
POWERBOOK_TOUCHPAD(15, 0x020e, 85, 16, 57), /* XXX Not tested. */
POWERBOOK_TOUCHPAD(15, 0x020f, 85, 16, 57),
/* 17 inch PowerBooks */
POWERBOOK_TOUCHPAD(17, 0x020d, 71, 26, 68) /* XXX Not tested. */
#undef POWERBOOK_TOUCHPAD
};
/* The number of supported devices. */
#define TPMS_NUM_DEVICES (sizeof(tpms_devices) / sizeof(tpms_devices[0]))
/*
* Types and prototypes.
*/
/* Device data. */
struct tpms_softc {
struct uhidev sc_hdev; /* USB parent (got the struct device). */
int sc_acc[TPMS_SENSORS]; /* Accumulated sensor values. */
signed char sc_prev[TPMS_SENSORS]; /* Previous sample. */
signed char sc_sample[TPMS_SENSORS]; /* Current sample. */
struct device *sc_wsmousedev; /* WSMouse device. */
int sc_noise; /* Amount of noise. */
int sc_threshold; /* Threshold value. */
int sc_x; /* Virtual position in horizontal
* direction (wsmouse position). */
int sc_x_factor; /* X-coordinate factor. */
int sc_x_raw; /* X-position of finger on trackpad. */
int sc_x_sensors; /* Number of X-sensors. */
int sc_y; /* Virtual position in vertical direction
* (wsmouse position). */
int sc_y_factor; /* Y-coordinate factor. */
int sc_y_raw; /* Y-position of finger on trackpad. */
int sc_y_sensors; /* Number of Y-sensors. */
uint32_t sc_buttons; /* Button state. */
uint32_t sc_status; /* Status flags. */
#define TPMS_ENABLED 1 /* Is the device enabled? */
#define TPMS_DYING 2 /* Is the device dying? */
#define TPMS_VALID 4 /* Is the previous sample valid? */
};
void tpms_intr(struct uhidev *, void *, unsigned int);
int tpms_enable(void *);
void tpms_disable(void *);
int tpms_ioctl(void *, unsigned long, caddr_t, int, struct proc *);
void reorder_sample(signed char *, signed char *);
int compute_delta(struct tpms_softc *, int *, int *, int *, uint32_t *);
int detect_pos(int *, int, int, int, int *, int *);
int smooth_pos(int, int, int);
/* Access methods for wsmouse. */
const struct wsmouse_accessops tpms_accessops = {
tpms_enable,
tpms_ioctl,
tpms_disable,
};
/* This take cares also of the basic device registration. */
int tpms_match(struct device *, void *, void *);
void tpms_attach(struct device *, struct device *, void *);
int tpms_detach(struct device *, int);
int tpms_activate(struct device *, enum devact);
struct cfdriver tpms_cd = {
NULL, "tpms", DV_DULL
};
const struct cfattach tpms_ca = {
sizeof(struct tpms_softc),
tpms_match,
tpms_attach,
tpms_detach,
tpms_activate,
};
/*
* Basic driver.
*/
/* Try to match the device at some uhidev. */
int
tpms_match(struct device *parent, void *match, void *aux)
{
struct usb_attach_arg *uaa = aux;
struct uhidev_attach_arg *uha = (struct uhidev_attach_arg *)uaa;
usb_device_descriptor_t *udd;
int i;
uint16_t vendor, product;
/*
* We just check if the vendor and product IDs have the magic numbers
* we expect.
*/
if ((udd = usbd_get_device_descriptor(uha->parent->sc_udev)) != NULL) {
vendor = UGETW(udd->idVendor);
product = UGETW(udd->idProduct);
for (i = 0; i < TPMS_NUM_DEVICES; i++) {
if (vendor == tpms_devices[i].vendor &&
product == tpms_devices[i].product)
return (UMATCH_IFACECLASS);
}
}
return (UMATCH_NONE);
}
/* Attach the device. */
void
tpms_attach(struct device *parent, struct device *self, void *aux)
{
struct tpms_softc *sc = (struct tpms_softc *)self;
struct usb_attach_arg *uaa = aux;
struct uhidev_attach_arg *uha = (struct uhidev_attach_arg *)uaa;
struct wsmousedev_attach_args a;
struct tpms_dev *pd;
usb_device_descriptor_t *udd;
int i;
uint16_t vendor, product;
/* Fill in device-specific parameters. */
if ((udd = usbd_get_device_descriptor(uha->parent->sc_udev)) != NULL) {
product = UGETW(udd->idProduct);
vendor = UGETW(udd->idVendor);
for (i = 0; i < TPMS_NUM_DEVICES; i++) {
pd = &tpms_devices[i];
if (product == pd->product && vendor == pd->vendor) {
printf(": %s\n", pd->descr);
sc->sc_noise = pd->noise;
sc->sc_threshold = pd->threshold;
sc->sc_x_factor = pd->x_factor;
sc->sc_x_sensors = pd->x_sensors;
sc->sc_y_factor = pd->y_factor;
sc->sc_y_sensors = pd->y_sensors;
break;
}
}
}
if (sc->sc_x_sensors <= 0 || sc->sc_x_sensors > TPMS_X_SENSORS ||
sc->sc_y_sensors <= 0 || sc->sc_y_sensors > TPMS_Y_SENSORS) {
printf(": unexpected sensors configuration (%d:%d)\n",
sc->sc_x_sensors, sc->sc_y_sensors);
return;
}
sc->sc_hdev.sc_intr = tpms_intr;
sc->sc_hdev.sc_parent = uha->parent;
sc->sc_hdev.sc_report_id = uha->reportid;
sc->sc_status = 0;
a.accessops = &tpms_accessops;
a.accesscookie = sc;
sc->sc_wsmousedev = config_found(self, &a, wsmousedevprint);
}
/* Detach the device. */
int
tpms_detach(struct device *self, int flags)
{
struct tpms_softc *sc = (struct tpms_softc *)self;
int ret;
/* The wsmouse driver does all the work. */
ret = 0;
if (sc->sc_wsmousedev != NULL)
ret = config_detach(sc->sc_wsmousedev, flags);
return (ret);
}
/* Activate the device. */
int
tpms_activate(struct device *self, enum devact act)
{
struct tpms_softc *sc = (struct tpms_softc *)self;
int ret;
if (act == DVACT_DEACTIVATE) {
ret = 0;
if (sc->sc_wsmousedev != NULL)
ret = config_deactivate(sc->sc_wsmousedev);
sc->sc_status |= TPMS_DYING;
return (ret);
}
return (EOPNOTSUPP);
}
/* Enable the device. */
int
tpms_enable(void *v)
{
struct tpms_softc *sc = v;
/* Check that we are not detaching or already enabled. */
if (sc->sc_status & TPMS_DYING)
return (EIO);
if (sc->sc_status & TPMS_ENABLED)
return (EBUSY);
sc->sc_status |= TPMS_ENABLED;
sc->sc_status &= ~TPMS_VALID;
sc->sc_buttons = 0;
memset(sc->sc_sample, 0, sizeof(sc->sc_sample));
return (uhidev_open(&sc->sc_hdev));
}
/* Disable the device. */
void
tpms_disable(void *v)
{
struct tpms_softc *sc = v;
if (!(sc->sc_status & TPMS_ENABLED))
return;
sc->sc_status &= ~TPMS_ENABLED;
uhidev_close(&sc->sc_hdev);
}
int
tpms_ioctl(void *v, unsigned long cmd, caddr_t data, int flag, struct proc *p)
{
switch (cmd) {
case WSMOUSEIO_GTYPE:
*(u_int *)data = WSMOUSE_TYPE_TPANEL;
return (0);
}
return (-1);
}
/*
* Interrupts & pointer movement.
*/
/* Handle interrupts. */
void
tpms_intr(struct uhidev *addr, void *ibuf, unsigned int len)
{
struct tpms_softc *sc = (struct tpms_softc *)addr;
signed char *data;
int dx, dy, dz, i, s;
uint32_t buttons;
/* Ignore incomplete data packets. */
if (len != TPMS_DATA_LEN)
return;
data = ibuf;
/* The last byte is 1 if the button is pressed and 0 otherwise. */
buttons = !!data[TPMS_DATA_LEN - 1];
/* Everything below assumes that the sample is reordered. */
reorder_sample(sc->sc_sample, data);
/* Is this the first sample? */
if (!(sc->sc_status & TPMS_VALID)) {
sc->sc_status |= TPMS_VALID;
sc->sc_x = sc->sc_y = -1;
sc->sc_x_raw = sc->sc_y_raw = -1;
memcpy(sc->sc_prev, sc->sc_sample, sizeof(sc->sc_prev));
memset(sc->sc_acc, 0, sizeof(sc->sc_acc));
return;
}
/* Accumulate the sensor change while keeping it nonnegative. */
for (i = 0; i < TPMS_SENSORS; i++) {
sc->sc_acc[i] += sc->sc_sample[i] - sc->sc_prev[i];
if (sc->sc_acc[i] < 0)
sc->sc_acc[i] = 0;
}
memcpy(sc->sc_prev, sc->sc_sample, sizeof(sc->sc_prev));
/* Compute change. */
dx = dy = dz = 0;
if (!compute_delta(sc, &dx, &dy, &dz, &buttons))
return;
/* Report to wsmouse. */
if ((dx != 0 || dy != 0 || dz != 0 || buttons != sc->sc_buttons) &&
sc->sc_wsmousedev != NULL) {
s = spltty();
wsmouse_input(sc->sc_wsmousedev, buttons, dx, -dy, dz, 0,
WSMOUSE_INPUT_DELTA);
splx(s);
}
sc->sc_buttons = buttons;
}
/*
* Reorder the sensor values so that all the X-sensors are before the
* Y-sensors in the natural order. Note that this might have to be
* rewritten if TPMS_X_SENSORS or TPMS_Y_SENSORS change.
*/
void
reorder_sample(signed char *to, signed char *from)
{
int i;
for (i = 0; i < 8; i++) {
/* X-sensors. */
to[i] = from[5 * i + 2];
to[i + 8] = from[5 * i + 4];
to[i + 16] = from[5 * i + 42];
#if 0
/*
* XXX This seems to introduce random vertical jumps, so
* we ignore these sensors until we figure out their meaning.
*/
if (i < 2)
to[i + 24] = from[5 * i + 44];
#endif /* 0 */
/* Y-sensors. */
to[i + 26] = from[5 * i + 1];
to[i + 34] = from[5 * i + 3];
}
}
/*
* Compute the change in x, y and z direction, update the button state
* (to simulate more than one button, scrolling etc.), and update the
* history. Note that dx, dy, dz and buttons are modified only if
* corresponding pressure is detected and should thus be initialised
* before the call. Return 0 on error.
*/
/* XXX Could we report something useful in dz? */
int
compute_delta(struct tpms_softc *sc, int *dx, int *dy, int *dz,
uint32_t * buttons)
{
int x_det, y_det, x_raw, y_raw, x_fingers, y_fingers, fingers, x, y;
x_det = detect_pos(sc->sc_acc, sc->sc_x_sensors, sc->sc_threshold,
sc->sc_x_factor, &x_raw, &x_fingers);
y_det = detect_pos(sc->sc_acc + TPMS_X_SENSORS, sc->sc_y_sensors,
sc->sc_threshold, sc->sc_y_factor,
&y_raw, &y_fingers);
fingers = max(x_fingers, y_fingers);
/* Check the number of fingers and if we have detected a position. */
if (fingers > 1) {
/* More than one finger detected, resetting. */
memset(sc->sc_acc, 0, sizeof(sc->sc_acc));
sc->sc_x_raw = sc->sc_y_raw = sc->sc_x = sc->sc_y = -1;
return 0;
} else if (x_det == 0 && y_det == 0) {
/* No position detected, resetting. */
memset(sc->sc_acc, 0, sizeof(sc->sc_acc));
sc->sc_x_raw = sc->sc_y_raw = sc->sc_x = sc->sc_y = -1;
} else if (x_det > 0 && y_det > 0) {
/* Smooth position. */
if (sc->sc_x_raw >= 0) {
sc->sc_x_raw = (3 * sc->sc_x_raw + x_raw) / 4;
sc->sc_y_raw = (3 * sc->sc_y_raw + y_raw) / 4;
/*
* Compute virtual position and change if we already
* have a decent position.
*/
if (sc->sc_x >= 0) {
x = smooth_pos(sc->sc_x, sc->sc_x_raw,
sc->sc_noise);
y = smooth_pos(sc->sc_y, sc->sc_y_raw,
sc->sc_noise);
*dx = x - sc->sc_x;
*dy = y - sc->sc_y;
sc->sc_x = x;
sc->sc_y = y;
} else {
/* Initialise virtual position. */
sc->sc_x = sc->sc_x_raw;
sc->sc_y = sc->sc_y_raw;
}
} else {
/* Initialise raw position. */
sc->sc_x_raw = x_raw;
sc->sc_y_raw = y_raw;
}
}
return (1);
}
/*
* Compute the new smoothed position from the previous smoothed position
* and the raw position.
*/
int
smooth_pos(int pos_old, int pos_raw, int noise)
{
int ad, delta;
delta = pos_raw - pos_old;
ad = abs(delta);
/* Too small changes are ignored. */
if (ad < noise / 2)
delta = 0;
/* A bit larger changes are smoothed. */
else if (ad < noise)
delta /= 4;
else if (ad < 2 * noise)
delta /= 2;
return (pos_old + delta);
}
/*
* Detect the position of the finger. Returns the total pressure.
* The position is returned in pos_ret and the number of fingers
* is returned in fingers_ret. The position returned in pos_ret
* is in [0, (n_sensors - 1) * factor - 1].
*/
int
detect_pos(int *sensors, int n_sensors, int threshold, int fact,
int *pos_ret, int *fingers_ret)
{
int i, w, s;
/*
* Compute the number of fingers, total pressure, and weighted
* position of the fingers.
*/
*fingers_ret = 0;
w = s = 0;
for (i = 0; i < n_sensors; i++) {
if (sensors[i] >= threshold) {
if (i == 0 || sensors[i - 1] < threshold)
*fingers_ret += 1;
s += sensors[i];
w += sensors[i] * i;
}
}
if (s > 0)
*pos_ret = w * fact / s;
return (s);
}