Input: byd - enable absolute mode

The Windows driver's settings dialog contains a visualization of the
regions for the hardware edge scrolling capability, which uses a
temporarily-enabled limited-resolution absolute mode.

This patch enables this during normal operation, and combines the
absolute packets with the existing relative packets to provide
accurate absolute position and touch reporting.

It also adds documentation for all known gesture packets and
initialization commands.
Reviewed-by: NChris Diamand <chris@diamand.org>
Signed-off-by: NRichard Pospesel <pospeselr@gmail.com>
Signed-off-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>

drivers/input/mouse/byd.c

@@ -12,10 +12,12 @@
 #include <linux/input.h>
 #include <linux/libps2.h>
 #include <linux/serio.h>
+#include <linux/slab.h>
 
 #include "psmouse.h"
 #include "byd.h"
 
+/* PS2 Bits */
 #define PS2_Y_OVERFLOW	BIT_MASK(7)
 #define PS2_X_OVERFLOW	BIT_MASK(6)
 #define PS2_Y_SIGN	BIT_MASK(5)
@@ -26,69 +28,249 @@
 #define PS2_LEFT	BIT_MASK(0)
 
 /*
- * The touchpad reports gestures in the last byte of each packet. It can take
- * any of the following values:
+ * BYD pad constants
  */
 
-/* One-finger scrolling in one of the edge scroll zones. */
-#define BYD_SCROLLUP		0xCA
-#define BYD_SCROLLDOWN		0x36
-#define BYD_SCROLLLEFT		0xCB
-#define BYD_SCROLLRIGHT		0x35
-/* Two-finger scrolling. */
-#define BYD_2DOWN		0x2B
-#define BYD_2UP			0xD5
-#define BYD_2LEFT		0xD6
-#define BYD_2RIGHT		0x2A
-/* Pinching in or out. */
-#define BYD_ZOOMOUT		0xD8
-#define BYD_ZOOMIN		0x28
-/* Three-finger swipe. */
-#define BYD_3UP			0xD3
-#define BYD_3DOWN		0x2D
-#define BYD_3LEFT		0xD4
-#define BYD_3RIGHT		0x2C
-/* Four-finger swipe. */
-#define BYD_4UP			0xCD
-#define BYD_4DOWN		0x33
+/*
+ * True device resolution is unknown, however experiments show the
+ * resolution is about 111 units/mm.
+ * Absolute coordinate packets are in the range 0-255 for both X and Y
+ * we pick ABS_X/ABS_Y dimensions which are multiples of 256 and in
+ * the right ballpark given the touchpad's physical dimensions and estimate
+ * resolution per spec sheet, device active area dimensions are
+ * 101.6 x 60.1 mm.
+ */
+#define BYD_PAD_WIDTH		11264
+#define BYD_PAD_HEIGHT		6656
+#define BYD_PAD_RESOLUTION	111
 
-int byd_detect(struct psmouse *psmouse, bool set_properties)
+/*
+ * Given the above dimensions, relative packets velocity is in multiples of
+ * 1 unit / 11 milliseconds.  We use this dt to estimate distance traveled
+ */
+#define BYD_DT			11
+/* Time in jiffies used to timeout various touch events (64 ms) */
+#define BYD_TOUCH_TIMEOUT	msecs_to_jiffies(64)
+
+/* BYD commands reverse engineered from windows driver */
+
+/*
+ * Swipe gesture from off-pad to on-pad
+ *  0 : disable
+ *  1 : enable
+ */
+#define BYD_CMD_SET_OFFSCREEN_SWIPE		0x10cc
+/*
+ * Tap and drag delay time
+ *  0 : disable
+ *  1 - 8 : least to most delay
+ */
+#define BYD_CMD_SET_TAP_DRAG_DELAY_TIME		0x10cf
+/*
+ * Physical buttons function mapping
+ *  0 : enable
+ *  4 : normal
+ *  5 : left button custom command
+ *  6 : right button custom command
+ *  8 : disable
+ */
+#define BYD_CMD_SET_PHYSICAL_BUTTONS		0x10d0
+/*
+ * Absolute mode (1 byte X/Y resolution)
+ *  0 : disable
+ *  2 : enable
+ */
+#define BYD_CMD_SET_ABSOLUTE_MODE		0x10d1
+/*
+ * Two finger scrolling
+ *  1 : vertical
+ *  2 : horizontal
+ *  3 : vertical + horizontal
+ *  4 : disable
+ */
+#define BYD_CMD_SET_TWO_FINGER_SCROLL		0x10d2
+/*
+ * Handedness
+ *  1 : right handed
+ *  2 : left handed
+ */
+#define BYD_CMD_SET_HANDEDNESS			0x10d3
+/*
+ * Tap to click
+ *  1 : enable
+ *  2 : disable
+ */
+#define BYD_CMD_SET_TAP				0x10d4
+/*
+ * Tap and drag
+ *  1 : tap and hold to drag
+ *  2 : tap and hold to drag + lock
+ *  3 : disable
+ */
+#define BYD_CMD_SET_TAP_DRAG			0x10d5
+/*
+ * Touch sensitivity
+ *  1 - 7 : least to most sensitive
+ */
+#define BYD_CMD_SET_TOUCH_SENSITIVITY		0x10d6
+/*
+ * One finger scrolling
+ *  1 : vertical
+ *  2 : horizontal
+ *  3 : vertical + horizontal
+ *  4 : disable
+ */
+#define BYD_CMD_SET_ONE_FINGER_SCROLL		0x10d7
+/*
+ * One finger scrolling function
+ *  1 : free scrolling
+ *  2 : edge motion
+ *  3 : free scrolling + edge motion
+ *  4 : disable
+ */
+#define BYD_CMD_SET_ONE_FINGER_SCROLL_FUNC	0x10d8
+/*
+ * Sliding speed
+ *  1 - 5 : slowest to fastest
+ */
+#define BYD_CMD_SET_SLIDING_SPEED		0x10da
+/*
+ * Edge motion
+ *  1 : disable
+ *  2 : enable when dragging
+ *  3 : enable when dragging and pointing
+ */
+#define BYD_CMD_SET_EDGE_MOTION			0x10db
+/*
+ * Left edge region size
+ *  0 - 7 : smallest to largest width
+ */
+#define BYD_CMD_SET_LEFT_EDGE_REGION		0x10dc
+/*
+ * Top edge region size
+ *  0 - 9 : smallest to largest height
+ */
+#define BYD_CMD_SET_TOP_EDGE_REGION		0x10dd
+/*
+ * Disregard palm press as clicks
+ *  1 - 6 : smallest to largest
+ */
+#define BYD_CMD_SET_PALM_CHECK			0x10de
+/*
+ * Right edge region size
+ *  0 - 7 : smallest to largest width
+ */
+#define BYD_CMD_SET_RIGHT_EDGE_REGION		0x10df
+/*
+ * Bottom edge region size
+ *  0 - 9 : smallest to largest height
+ */
+#define BYD_CMD_SET_BOTTOM_EDGE_REGION		0x10e1
+/*
+ * Multitouch gestures
+ *  1 : enable
+ *  2 : disable
+ */
+#define BYD_CMD_SET_MULTITOUCH			0x10e3
+/*
+ * Edge motion speed
+ *  0 : control with finger pressure
+ *  1 - 9 : slowest to fastest
+ */
+#define BYD_CMD_SET_EDGE_MOTION_SPEED		0x10e4
+/*
+ * Two finger scolling function
+ *  0 : free scrolling
+ *  1 : free scrolling (with momentum)
+ *  2 : edge motion
+ *  3 : free scrolling (with momentum) + edge motion
+ *  4 : disable
+ */
+#define BYD_CMD_SET_TWO_FINGER_SCROLL_FUNC	0x10e5
+
+/*
+ * The touchpad generates a mixture of absolute and relative packets, indicated
+ * by the the last byte of each packet being set to one of the following:
+ */
+#define BYD_PACKET_ABSOLUTE			0xf8
+#define BYD_PACKET_RELATIVE			0x00
+/* Multitouch gesture packets */
+#define BYD_PACKET_PINCH_IN			0xd8
+#define BYD_PACKET_PINCH_OUT			0x28
+#define BYD_PACKET_ROTATE_CLOCKWISE		0x29
+#define BYD_PACKET_ROTATE_ANTICLOCKWISE		0xd7
+#define BYD_PACKET_TWO_FINGER_SCROLL_RIGHT	0x2a
+#define BYD_PACKET_TWO_FINGER_SCROLL_DOWN	0x2b
+#define BYD_PACKET_TWO_FINGER_SCROLL_UP		0xd5
+#define BYD_PACKET_TWO_FINGER_SCROLL_LEFT	0xd6
+#define BYD_PACKET_THREE_FINGER_SWIPE_RIGHT	0x2c
+#define BYD_PACKET_THREE_FINGER_SWIPE_DOWN	0x2d
+#define BYD_PACKET_THREE_FINGER_SWIPE_UP	0xd3
+#define BYD_PACKET_THREE_FINGER_SWIPE_LEFT	0xd4
+#define BYD_PACKET_FOUR_FINGER_DOWN		0x33
+#define BYD_PACKET_FOUR_FINGER_UP		0xcd
+#define BYD_PACKET_REGION_SCROLL_RIGHT		0x35
+#define BYD_PACKET_REGION_SCROLL_DOWN		0x36
+#define BYD_PACKET_REGION_SCROLL_UP		0xca
+#define BYD_PACKET_REGION_SCROLL_LEFT		0xcb
+#define BYD_PACKET_RIGHT_CORNER_CLICK		0xd2
+#define BYD_PACKET_LEFT_CORNER_CLICK		0x2e
+#define BYD_PACKET_LEFT_AND_RIGHT_CORNER_CLICK	0x2f
+#define BYD_PACKET_ONTO_PAD_SWIPE_RIGHT		0x37
+#define BYD_PACKET_ONTO_PAD_SWIPE_DOWN		0x30
+#define BYD_PACKET_ONTO_PAD_SWIPE_UP		0xd0
+#define BYD_PACKET_ONTO_PAD_SWIPE_LEFT		0xc9
+
+struct byd_data {
+	struct timer_list timer;
+	s32 abs_x;
+	s32 abs_y;
+	typeof(jiffies) last_touch_time;
+	bool btn_left;
+	bool btn_right;
+	bool touch;
+};
+
+static void byd_report_input(struct psmouse *psmouse)
 {
-	struct ps2dev *ps2dev = &psmouse->ps2dev;
-	unsigned char param[4];
+	struct byd_data *priv = psmouse->private;
+	struct input_dev *dev = psmouse->dev;
 
-	param[0] = 0x03;
-	param[1] = 0x00;
-	param[2] = 0x00;
-	param[3] = 0x00;
+	input_report_key(dev, BTN_TOUCH, priv->touch);
+	input_report_key(dev, BTN_TOOL_FINGER, priv->touch);
 
-	if (ps2_command(ps2dev, param, PSMOUSE_CMD_SETRES))
-		return -1;
-	if (ps2_command(ps2dev, param, PSMOUSE_CMD_SETRES))
-		return -1;
-	if (ps2_command(ps2dev, param, PSMOUSE_CMD_SETRES))
-		return -1;
-	if (ps2_command(ps2dev, param, PSMOUSE_CMD_SETRES))
-		return -1;
-	if (ps2_command(ps2dev, param, PSMOUSE_CMD_GETINFO))
-		return -1;
+	input_report_abs(dev, ABS_X, priv->abs_x);
+	input_report_abs(dev, ABS_Y, priv->abs_y);
+	input_report_key(dev, BTN_LEFT, priv->btn_left);
+	input_report_key(dev, BTN_RIGHT, priv->btn_right);
 
-	if (param[1] != 0x03 || param[2] != 0x64)
-		return -ENODEV;
+	input_sync(dev);
+}
 
-	psmouse_dbg(psmouse, "BYD touchpad detected\n");
+static void byd_clear_touch(unsigned long data)
+{
+	struct psmouse *psmouse = (struct psmouse *)data;
+	struct byd_data *priv = psmouse->private;
 
-	if (set_properties) {
-		psmouse->vendor = "BYD";
-		psmouse->name = "TouchPad";
-	}
+	serio_pause_rx(psmouse->ps2dev.serio);
+	priv->touch = false;
 
-	return 0;
+	byd_report_input(psmouse);
+
+	serio_continue_rx(psmouse->ps2dev.serio);
+
+	/*
+	 * Move cursor back to center of pad when we lose touch - this
+	 * specifically improves user experience when moving cursor with one
+	 * finger, and pressing a button with another.
+	 */
+	priv->abs_x = BYD_PAD_WIDTH / 2;
+	priv->abs_y = BYD_PAD_HEIGHT / 2;
 }
 
 static psmouse_ret_t byd_process_byte(struct psmouse *psmouse)
 {
-	struct input_dev *dev = psmouse->dev;
+	struct byd_data *priv = psmouse->private;
 	u8 *pkt = psmouse->packet;
 
 	if (psmouse->pktcnt > 0 && !(pkt[0] & PS2_ALWAYS_1)) {
@@ -102,53 +284,34 @@ static psmouse_ret_t byd_process_byte(struct psmouse *psmouse)
 
 	/* Otherwise, a full packet has been received */
 	switch (pkt[3]) {
-	case 0: {
+	case BYD_PACKET_ABSOLUTE:
+		/* Only use absolute packets for the start of movement. */
+		if (!priv->touch) {
+			/* needed to detect tap */
+			typeof(jiffies) tap_time =
+				priv->last_touch_time + BYD_TOUCH_TIMEOUT;
+			priv->touch = time_after(jiffies, tap_time);
+
+			/* init abs position */
+			priv->abs_x = pkt[1] * (BYD_PAD_WIDTH / 256);
+			priv->abs_y = (255 - pkt[2]) * (BYD_PAD_HEIGHT / 256);
+		}
+		break;
+	case BYD_PACKET_RELATIVE: {
 		/* Standard packet */
 		/* Sign-extend if a sign bit is set. */
-		unsigned int signx = pkt[0] & PS2_X_SIGN ? ~0xFF : 0;
-		unsigned int signy = pkt[0] & PS2_Y_SIGN ? ~0xFF : 0;
-		int dx = signx | (int) pkt[1];
-		int dy = signy | (int) pkt[2];
+		u32 signx = pkt[0] & PS2_X_SIGN ? ~0xFF : 0;
+		u32 signy = pkt[0] & PS2_Y_SIGN ? ~0xFF : 0;
+		s32 dx = signx | (int) pkt[1];
+		s32 dy = signy | (int) pkt[2];
 
-		input_report_rel(psmouse->dev, REL_X, dx);
-		input_report_rel(psmouse->dev, REL_Y, -dy);
+		/* Update position based on velocity */
+		priv->abs_x += dx * BYD_DT;
+		priv->abs_y -= dy * BYD_DT;
 
-		input_report_key(psmouse->dev, BTN_LEFT, pkt[0] & PS2_LEFT);
-		input_report_key(psmouse->dev, BTN_RIGHT, pkt[0] & PS2_RIGHT);
-		input_report_key(psmouse->dev, BTN_MIDDLE, pkt[0] & PS2_MIDDLE);
+		priv->touch = true;
 		break;
 	}
-
-	case BYD_SCROLLDOWN:
-	case BYD_2DOWN:
-		input_report_rel(dev, REL_WHEEL, -1);
-		break;
-
-	case BYD_SCROLLUP:
-	case BYD_2UP:
-		input_report_rel(dev, REL_WHEEL, 1);
-		break;
-
-	case BYD_SCROLLLEFT:
-	case BYD_2LEFT:
-		input_report_rel(dev, REL_HWHEEL, -1);
-		break;
-
-	case BYD_SCROLLRIGHT:
-	case BYD_2RIGHT:
-		input_report_rel(dev, REL_HWHEEL, 1);
-		break;
-
-	case BYD_ZOOMOUT:
-	case BYD_ZOOMIN:
-	case BYD_3UP:
-	case BYD_3DOWN:
-	case BYD_3LEFT:
-	case BYD_3RIGHT:
-	case BYD_4UP:
-	case BYD_4DOWN:
-		break;
-
 	default:
 		psmouse_warn(psmouse,
 			     "Unrecognized Z: pkt = %02x %02x %02x %02x\n",
@@ -157,134 +320,76 @@ static psmouse_ret_t byd_process_byte(struct psmouse *psmouse)
 		return PSMOUSE_BAD_DATA;
 	}
 
-	input_sync(dev);
+	priv->btn_left = pkt[0] & PS2_LEFT;
+	priv->btn_right = pkt[0] & PS2_RIGHT;
 
-	return PSMOUSE_FULL_PACKET;
-}
+	byd_report_input(psmouse);
 
-/* Send a sequence of bytes, where each is ACKed before the next is sent. */
-static int byd_send_sequence(struct psmouse *psmouse, const u8 *seq, size_t len)
-{
-	unsigned int i;
-
-	for (i = 0; i < len; ++i) {
-		if (ps2_command(&psmouse->ps2dev, NULL, seq[i]))
-			return -1;
+	/* Reset time since last touch. */
+	if (priv->touch) {
+		priv->last_touch_time = jiffies;
+		mod_timer(&priv->timer, jiffies + BYD_TOUCH_TIMEOUT);
 	}
-	return 0;
-}
-
-/* Keep scrolling after fingers are removed. */
-#define SCROLL_INERTIAL		0x01
-#define SCROLL_NO_INERTIAL	0x02
-
-/* Clicking can be done by tapping or pressing. */
-#define CLICK_BOTH		0x01
-/* Clicking can only be done by pressing. */
-#define CLICK_PRESS_ONLY	0x02
 
-static int byd_enable(struct psmouse *psmouse)
-{
-	const u8 seq1[] = { 0xE2, 0x00, 0xE0, 0x02, 0xE0 };
-	const u8 seq2[] = {
-		0xD3, 0x01,
-		0xD0, 0x00,
-		0xD0, 0x04,
-		/* Whether clicking is done by tapping or pressing. */
-		0xD4, CLICK_PRESS_ONLY,
-		0xD5, 0x01,
-		0xD7, 0x03,
-		/* Vertical and horizontal one-finger scroll zone inertia. */
-		0xD8, SCROLL_INERTIAL,
-		0xDA, 0x05,
-		0xDB, 0x02,
-		0xE4, 0x05,
-		0xD6, 0x01,
-		0xDE, 0x04,
-		0xE3, 0x01,
-		0xCF, 0x00,
-		0xD2, 0x03,
-		/* Vertical and horizontal two-finger scrolling inertia. */
-		0xE5, SCROLL_INERTIAL,
-		0xD9, 0x02,
-		0xD9, 0x07,
-		0xDC, 0x03,
-		0xDD, 0x03,
-		0xDF, 0x03,
-		0xE1, 0x03,
-		0xD1, 0x00,
-		0xCE, 0x00,
-		0xCC, 0x00,
-		0xE0, 0x00,
-		0xE2, 0x01
-	};
-	u8 param[4];
-
-	if (byd_send_sequence(psmouse, seq1, ARRAY_SIZE(seq1)))
-		return -1;
-
-	/* Send a 0x01 command, which should return 4 bytes. */
-	if (ps2_command(&psmouse->ps2dev, param, 0x0401))
-		return -1;
-
-	if (byd_send_sequence(psmouse, seq2, ARRAY_SIZE(seq2)))
-		return -1;
-
-	return 0;
+	return PSMOUSE_FULL_PACKET;
 }
 
-/*
- * Send the set of PS/2 commands required to make it identify as an
- * intellimouse with 4-byte instead of 3-byte packets.
- */
-static int byd_send_intellimouse_sequence(struct psmouse *psmouse)
+static int byd_reset_touchpad(struct psmouse *psmouse)
 {
 	struct ps2dev *ps2dev = &psmouse->ps2dev;
 	u8 param[4];
-	int i;
+	size_t i;
+
 	const struct {
 		u16 command;
 		u8 arg;
 	} seq[] = {
-		{ PSMOUSE_CMD_RESET_BAT, 0 },
-		{ PSMOUSE_CMD_RESET_BAT, 0 },
-		{ PSMOUSE_CMD_GETID, 0 },
-		{ PSMOUSE_CMD_SETSCALE11, 0 },
-		{ PSMOUSE_CMD_SETSCALE11, 0 },
-		{ PSMOUSE_CMD_SETSCALE11, 0 },
-		{ PSMOUSE_CMD_GETINFO, 0 },
-		{ PSMOUSE_CMD_SETRES, 0x03 },
+		/*
+		 * Intellimouse initialization sequence, to get 4-byte instead
+		 * of 3-byte packets.
+		 */
 		{ PSMOUSE_CMD_SETRATE, 0xC8 },
 		{ PSMOUSE_CMD_SETRATE, 0x64 },
 		{ PSMOUSE_CMD_SETRATE, 0x50 },
 		{ PSMOUSE_CMD_GETID, 0 },
-		{ PSMOUSE_CMD_SETRATE, 0xC8 },
-		{ PSMOUSE_CMD_SETRATE, 0xC8 },
-		{ PSMOUSE_CMD_SETRATE, 0x50 },
-		{ PSMOUSE_CMD_GETID, 0 },
-		{ PSMOUSE_CMD_SETRATE, 0x64 },
-		{ PSMOUSE_CMD_SETRES, 0x03 },
-		{ PSMOUSE_CMD_ENABLE, 0 }
+		{ PSMOUSE_CMD_ENABLE, 0 },
+		/*
+		 * BYD-specific initialization, which enables absolute mode and
+		 * (if desired), the touchpad's built-in gesture detection.
+		 */
+		{ 0x10E2, 0x00 },
+		{ 0x10E0, 0x02 },
+		/* The touchpad should reply with 4 seemingly-random bytes */
+		{ 0x14E0, 0x01 },
+		/* Pairs of parameters and values. */
+		{ BYD_CMD_SET_HANDEDNESS, 0x01 },
+		{ BYD_CMD_SET_PHYSICAL_BUTTONS, 0x04 },
+		{ BYD_CMD_SET_TAP, 0x02 },
+		{ BYD_CMD_SET_ONE_FINGER_SCROLL, 0x04 },
+		{ BYD_CMD_SET_ONE_FINGER_SCROLL_FUNC, 0x04 },
+		{ BYD_CMD_SET_EDGE_MOTION, 0x01 },
+		{ BYD_CMD_SET_PALM_CHECK, 0x00 },
+		{ BYD_CMD_SET_MULTITOUCH, 0x02 },
+		{ BYD_CMD_SET_TWO_FINGER_SCROLL, 0x04 },
+		{ BYD_CMD_SET_TWO_FINGER_SCROLL_FUNC, 0x04 },
+		{ BYD_CMD_SET_LEFT_EDGE_REGION, 0x00 },
+		{ BYD_CMD_SET_TOP_EDGE_REGION, 0x00 },
+		{ BYD_CMD_SET_RIGHT_EDGE_REGION, 0x00 },
+		{ BYD_CMD_SET_BOTTOM_EDGE_REGION, 0x00 },
+		{ BYD_CMD_SET_ABSOLUTE_MODE, 0x02 },
+		/* Finalize initialization. */
+		{ 0x10E0, 0x00 },
+		{ 0x10E2, 0x01 },
 	};
 
-	memset(param, 0, sizeof(param));
 	for (i = 0; i < ARRAY_SIZE(seq); ++i) {
+		memset(param, 0, sizeof(param));
 		param[0] = seq[i].arg;
 		if (ps2_command(ps2dev, param, seq[i].command))
-			return -1;
+			return -EIO;
 	}
 
-	return 0;
-}
-
-static int byd_reset_touchpad(struct psmouse *psmouse)
-{
-	if (byd_send_intellimouse_sequence(psmouse))
-		return -EIO;
-
-	if (byd_enable(psmouse))
-		return -EIO;
-
+	psmouse_set_state(psmouse, PSMOUSE_ACTIVATED);
 	return 0;
 }
 
@@ -314,9 +419,50 @@ static int byd_reconnect(struct psmouse *psmouse)
 	return 0;
 }
 
+static void byd_disconnect(struct psmouse *psmouse)
+{
+	struct byd_data *priv = psmouse->private;
+
+	if (priv) {
+		del_timer(&priv->timer);
+		kfree(psmouse->private);
+		psmouse->private = NULL;
+	}
+}
+
+int byd_detect(struct psmouse *psmouse, bool set_properties)
+{
+	struct ps2dev *ps2dev = &psmouse->ps2dev;
+	u8 param[4] = {0x03, 0x00, 0x00, 0x00};
+
+	if (ps2_command(ps2dev, param, PSMOUSE_CMD_SETRES))
+		return -1;
+	if (ps2_command(ps2dev, param, PSMOUSE_CMD_SETRES))
+		return -1;
+	if (ps2_command(ps2dev, param, PSMOUSE_CMD_SETRES))
+		return -1;
+	if (ps2_command(ps2dev, param, PSMOUSE_CMD_SETRES))
+		return -1;
+	if (ps2_command(ps2dev, param, PSMOUSE_CMD_GETINFO))
+		return -1;
+
+	if (param[1] != 0x03 || param[2] != 0x64)
+		return -ENODEV;
+
+	psmouse_dbg(psmouse, "BYD touchpad detected\n");
+
+	if (set_properties) {
+		psmouse->vendor = "BYD";
+		psmouse->name = "TouchPad";
+	}
+
+	return 0;
+}
+
 int byd_init(struct psmouse *psmouse)
 {
 	struct input_dev *dev = psmouse->dev;
+	struct byd_data *priv;
 
 	if (psmouse_reset(psmouse))
 		return -EIO;
@@ -324,14 +470,39 @@ int byd_init(struct psmouse *psmouse)
 	if (byd_reset_touchpad(psmouse))
 		return -EIO;
 
+	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	memset(priv, 0, sizeof(*priv));
+	setup_timer(&priv->timer, byd_clear_touch, (unsigned long) psmouse);
+
+	psmouse->private = priv;
+	psmouse->disconnect = byd_disconnect;
 	psmouse->reconnect = byd_reconnect;
 	psmouse->protocol_handler = byd_process_byte;
 	psmouse->pktsize = 4;
 	psmouse->resync_time = 0;
 
-	__set_bit(BTN_MIDDLE, dev->keybit);
-	__set_bit(REL_WHEEL, dev->relbit);
-	__set_bit(REL_HWHEEL, dev->relbit);
+	__set_bit(INPUT_PROP_POINTER, dev->propbit);
+	/* Touchpad */
+	__set_bit(BTN_TOUCH, dev->keybit);
+	__set_bit(BTN_TOOL_FINGER, dev->keybit);
+	/* Buttons */
+	__set_bit(BTN_LEFT, dev->keybit);
+	__set_bit(BTN_RIGHT, dev->keybit);
+	__clear_bit(BTN_MIDDLE, dev->keybit);
+
+	/* Absolute position */
+	__set_bit(EV_ABS, dev->evbit);
+	input_set_abs_params(dev, ABS_X, 0, BYD_PAD_WIDTH, 0, 0);
+	input_set_abs_params(dev, ABS_Y, 0, BYD_PAD_HEIGHT, 0, 0);
+	input_abs_set_res(dev, ABS_X, BYD_PAD_RESOLUTION);
+	input_abs_set_res(dev, ABS_Y, BYD_PAD_RESOLUTION);
+	/* No relative support */
+	__clear_bit(EV_REL, dev->evbit);
+	__clear_bit(REL_X, dev->relbit);
+	__clear_bit(REL_Y, dev->relbit);
 
 	return 0;
 }

drivers/input/mouse/psmouse-base.c

@@ -846,7 +846,7 @@ static const struct psmouse_protocol psmouse_protocols[] = {
 #ifdef CONFIG_MOUSE_PS2_BYD
 	{
 		.type		= PSMOUSE_BYD,
-		.name		= "BydPS/2",
+		.name		= "BYDPS/2",
 		.alias		= "byd",
 		.detect		= byd_detect,
 		.init		= byd_init,