/* $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 #include #include #include #include #include #include #include #include #include #include #include /* * 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); }