Input: ALPS - add support for DualPoint device on Dell XT2 model

The device uses special MPU controller that necessitates the new
initialization sequence for the device. We also define a new protocol for
the trackpad that allows reporting better resolution than older V2
protocol.

Signed-off-by: Yunkang Tang <yunkang.tang@cn.alps.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

2 files changed, 204 insertions, 3 deletions

diff --git a/drivers/input/mouse/alps.c b/drivers/input/mouse/alps.c
index ca7a26f1dce8..5cf62e315218 100644
--- a/drivers/input/mouse/alps.c
+++ b/drivers/input/mouse/alps.c
@@ -70,6 +70,25 @@ static const struct alps_nibble_commands alps_v4_nibble_commands[] = {
 	{ PSMOUSE_CMD_SETSCALE11,	0x00 }, /* f */
 };
 
+static const struct alps_nibble_commands alps_v6_nibble_commands[] = {
+	{ PSMOUSE_CMD_ENABLE,		0x00 }, /* 0 */
+	{ PSMOUSE_CMD_SETRATE,		0x0a }, /* 1 */
+	{ PSMOUSE_CMD_SETRATE,		0x14 }, /* 2 */
+	{ PSMOUSE_CMD_SETRATE,		0x28 }, /* 3 */
+	{ PSMOUSE_CMD_SETRATE,		0x3c }, /* 4 */
+	{ PSMOUSE_CMD_SETRATE,		0x50 }, /* 5 */
+	{ PSMOUSE_CMD_SETRATE,		0x64 }, /* 6 */
+	{ PSMOUSE_CMD_SETRATE,		0xc8 }, /* 7 */
+	{ PSMOUSE_CMD_GETID,		0x00 }, /* 8 */
+	{ PSMOUSE_CMD_GETINFO,		0x00 }, /* 9 */
+	{ PSMOUSE_CMD_SETRES,		0x00 }, /* a */
+	{ PSMOUSE_CMD_SETRES,		0x01 }, /* b */
+	{ PSMOUSE_CMD_SETRES,		0x02 }, /* c */
+	{ PSMOUSE_CMD_SETRES,		0x03 }, /* d */
+	{ PSMOUSE_CMD_SETSCALE21,	0x00 }, /* e */
+	{ PSMOUSE_CMD_SETSCALE11,	0x00 }, /* f */
+};
+
 
 #define ALPS_DUALPOINT		0x02	/* touchpad has trackstick */
 #define ALPS_PASS		0x04	/* device has a pass-through port */
@@ -103,6 +122,7 @@ static const struct alps_model_info alps_model_data[] = {
 	/* Dell Latitude E5500, E6400, E6500, Precision M4400 */
 	{ { 0x62, 0x02, 0x14 }, 0x00, ALPS_PROTO_V2, 0xcf, 0xcf,
 		ALPS_PASS | ALPS_DUALPOINT | ALPS_PS2_INTERLEAVED },
+	{ { 0x73, 0x00, 0x14 }, 0x00, ALPS_PROTO_V6, 0xff, 0xff, ALPS_DUALPOINT },		/* Dell XT2 */
 	{ { 0x73, 0x02, 0x50 }, 0x00, ALPS_PROTO_V2, 0xcf, 0xcf, ALPS_FOUR_BUTTONS },		/* Dell Vostro 1400 */
 	{ { 0x52, 0x01, 0x14 }, 0x00, ALPS_PROTO_V2, 0xff, 0xff,
 		ALPS_PASS | ALPS_DUALPOINT | ALPS_PS2_INTERLEAVED },				/* Toshiba Tecra A11-11L */
@@ -645,6 +665,76 @@ static void alps_process_packet_v3(struct psmouse *psmouse)
 	alps_process_touchpad_packet_v3(psmouse);
 }
 
+static void alps_process_packet_v6(struct psmouse *psmouse)
+{
+	struct alps_data *priv = psmouse->private;
+	unsigned char *packet = psmouse->packet;
+	struct input_dev *dev = psmouse->dev;
+	struct input_dev *dev2 = priv->dev2;
+	int x, y, z, left, right, middle;
+
+	/*
+	 * We can use Byte5 to distinguish if the packet is from Touchpad
+	 * or Trackpoint.
+	 * Touchpad:	0 - 0x7E
+	 * Trackpoint:	0x7F
+	 */
+	if (packet[5] == 0x7F) {
+		/* It should be a DualPoint when received Trackpoint packet */
+		if (!(priv->flags & ALPS_DUALPOINT))
+			return;
+
+		/* Trackpoint packet */
+		x = packet[1] | ((packet[3] & 0x20) << 2);
+		y = packet[2] | ((packet[3] & 0x40) << 1);
+		z = packet[4];
+		left = packet[3] & 0x01;
+		right = packet[3] & 0x02;
+		middle = packet[3] & 0x04;
+
+		/* To prevent the cursor jump when finger lifted */
+		if (x == 0x7F && y == 0x7F && z == 0x7F)
+			x = y = z = 0;
+
+		/* Divide 4 since trackpoint's speed is too fast */
+		input_report_rel(dev2, REL_X, (char)x / 4);
+		input_report_rel(dev2, REL_Y, -((char)y / 4));
+
+		input_report_key(dev2, BTN_LEFT, left);
+		input_report_key(dev2, BTN_RIGHT, right);
+		input_report_key(dev2, BTN_MIDDLE, middle);
+
+		input_sync(dev2);
+		return;
+	}
+
+	/* Touchpad packet */
+	x = packet[1] | ((packet[3] & 0x78) << 4);
+	y = packet[2] | ((packet[4] & 0x78) << 4);
+	z = packet[5];
+	left = packet[3] & 0x01;
+	right = packet[3] & 0x02;
+
+	if (z > 30)
+		input_report_key(dev, BTN_TOUCH, 1);
+	if (z < 25)
+		input_report_key(dev, BTN_TOUCH, 0);
+
+	if (z > 0) {
+		input_report_abs(dev, ABS_X, x);
+		input_report_abs(dev, ABS_Y, y);
+	}
+
+	input_report_abs(dev, ABS_PRESSURE, z);
+	input_report_key(dev, BTN_TOOL_FINGER, z > 0);
+
+	/* v6 touchpad does not have middle button */
+	input_report_key(dev, BTN_LEFT, left);
+	input_report_key(dev, BTN_RIGHT, right);
+
+	input_sync(dev);
+}
+
 static void alps_process_packet_v4(struct psmouse *psmouse)
 {
 	struct alps_data *priv = psmouse->private;
@@ -897,7 +987,7 @@ static psmouse_ret_t alps_process_byte(struct psmouse *psmouse)
 	}
 
 	/* Bytes 2 - pktsize should have 0 in the highest bit */
-	if (priv->proto_version != ALPS_PROTO_V5 &&
+	if ((priv->proto_version < ALPS_PROTO_V5) &&
 	    psmouse->pktcnt >= 2 && psmouse->pktcnt <= psmouse->pktsize &&
 	    (psmouse->packet[psmouse->pktcnt - 1] & 0x80)) {
 		psmouse_dbg(psmouse, "refusing packet[%i] = %x\n",
@@ -1085,6 +1175,80 @@ static int alps_absolute_mode_v1_v2(struct psmouse *psmouse)
 	return ps2_command(&psmouse->ps2dev, NULL, PSMOUSE_CMD_SETPOLL);
 }
 
+static int alps_monitor_mode_send_word(struct psmouse *psmouse, u16 word)
+{
+	int i, nibble;
+
+	/*
+	 * b0-b11 are valid bits, send sequence is inverse.
+	 * e.g. when word = 0x0123, nibble send sequence is 3, 2, 1
+	 */
+	for (i = 0; i <= 8; i += 4) {
+		nibble = (word >> i) & 0xf;
+		if (alps_command_mode_send_nibble(psmouse, nibble))
+			return -1;
+	}
+
+	return 0;
+}
+
+static int alps_monitor_mode_write_reg(struct psmouse *psmouse,
+				       u16 addr, u16 value)
+{
+	struct ps2dev *ps2dev = &psmouse->ps2dev;
+
+	/* 0x0A0 is the command to write the word */
+	if (ps2_command(ps2dev, NULL, PSMOUSE_CMD_ENABLE) ||
+	    alps_monitor_mode_send_word(psmouse, 0x0A0) ||
+	    alps_monitor_mode_send_word(psmouse, addr) ||
+	    alps_monitor_mode_send_word(psmouse, value) ||
+	    ps2_command(ps2dev, NULL, PSMOUSE_CMD_DISABLE))
+		return -1;
+
+	return 0;
+}
+
+static int alps_monitor_mode(struct psmouse *psmouse, bool enable)
+{
+	struct ps2dev *ps2dev = &psmouse->ps2dev;
+
+	if (enable) {
+		/* EC E9 F5 F5 E7 E6 E7 E9 to enter monitor mode */
+		if (ps2_command(ps2dev, NULL, PSMOUSE_CMD_RESET_WRAP) ||
+		    ps2_command(ps2dev, NULL, PSMOUSE_CMD_GETINFO) ||
+		    ps2_command(ps2dev, NULL, PSMOUSE_CMD_DISABLE) ||
+		    ps2_command(ps2dev, NULL, PSMOUSE_CMD_DISABLE) ||
+		    ps2_command(ps2dev, NULL, PSMOUSE_CMD_SETSCALE21) ||
+		    ps2_command(ps2dev, NULL, PSMOUSE_CMD_SETSCALE11) ||
+		    ps2_command(ps2dev, NULL, PSMOUSE_CMD_SETSCALE21) ||
+		    ps2_command(ps2dev, NULL, PSMOUSE_CMD_GETINFO))
+			return -1;
+	} else {
+		/* EC to exit monitor mode */
+		if (ps2_command(ps2dev, NULL, PSMOUSE_CMD_RESET_WRAP))
+			return -1;
+	}
+
+	return 0;
+}
+
+static int alps_absolute_mode_v6(struct psmouse *psmouse)
+{
+	u16 reg_val = 0x181;
+	int ret = -1;
+
+	/* enter monitor mode, to write the register */
+	if (alps_monitor_mode(psmouse, true))
+		return -1;
+
+	ret = alps_monitor_mode_write_reg(psmouse, 0x000, reg_val);
+
+	if (alps_monitor_mode(psmouse, false))
+		ret = -1;
+
+	return ret;
+}
+
 static int alps_get_status(struct psmouse *psmouse, char *param)
 {
 	/* Get status: 0xF5 0xF5 0xF5 0xE9 */
@@ -1189,6 +1353,32 @@ static int alps_hw_init_v1_v2(struct psmouse *psmouse)
 	return 0;
 }
 
+static int alps_hw_init_v6(struct psmouse *psmouse)
+{
+	unsigned char param[2] = {0xC8, 0x14};
+
+	/* Enter passthrough mode to let trackpoint enter 6byte raw mode */
+	if (alps_passthrough_mode_v2(psmouse, true))
+		return -1;
+
+	if (ps2_command(&psmouse->ps2dev, NULL, PSMOUSE_CMD_SETSCALE11) ||
+	    ps2_command(&psmouse->ps2dev, NULL, PSMOUSE_CMD_SETSCALE11) ||
+	    ps2_command(&psmouse->ps2dev, NULL, PSMOUSE_CMD_SETSCALE11) ||
+	    ps2_command(&psmouse->ps2dev, &param[0], PSMOUSE_CMD_SETRATE) ||
+	    ps2_command(&psmouse->ps2dev, &param[1], PSMOUSE_CMD_SETRATE))
+		return -1;
+
+	if (alps_passthrough_mode_v2(psmouse, false))
+		return -1;
+
+	if (alps_absolute_mode_v6(psmouse)) {
+		psmouse_err(psmouse, "Failed to enable absolute mode\n");
+		return -1;
+	}
+
+	return 0;
+}
+
 /*
  * Enable or disable passthrough mode to the trackstick.
  */
@@ -1553,6 +1743,8 @@ static void alps_set_defaults(struct alps_data *priv)
 		priv->hw_init = alps_hw_init_v1_v2;
 		priv->process_packet = alps_process_packet_v1_v2;
 		priv->set_abs_params = alps_set_abs_params_st;
+		priv->x_max = 1023;
+		priv->y_max = 767;
 		break;
 	case ALPS_PROTO_V3:
 		priv->hw_init = alps_hw_init_v3;
@@ -1584,6 +1776,14 @@ static void alps_set_defaults(struct alps_data *priv)
 		priv->x_bits = 23;
 		priv->y_bits = 12;
 		break;
+	case ALPS_PROTO_V6:
+		priv->hw_init = alps_hw_init_v6;
+		priv->process_packet = alps_process_packet_v6;
+		priv->set_abs_params = alps_set_abs_params_st;
+		priv->nibble_commands = alps_v6_nibble_commands;
+		priv->x_max = 2047;
+		priv->y_max = 1535;
+		break;
 	}
 }
 
@@ -1705,8 +1905,8 @@ static void alps_disconnect(struct psmouse *psmouse)
 static void alps_set_abs_params_st(struct alps_data *priv,
 				   struct input_dev *dev1)
 {
-	input_set_abs_params(dev1, ABS_X, 0, 1023, 0, 0);
-	input_set_abs_params(dev1, ABS_Y, 0, 767, 0, 0);
+	input_set_abs_params(dev1, ABS_X, 0, priv->x_max, 0, 0);
+	input_set_abs_params(dev1, ABS_Y, 0, priv->y_max, 0, 0);
 }
 
 static void alps_set_abs_params_mt(struct alps_data *priv,
diff --git a/drivers/input/mouse/alps.h b/drivers/input/mouse/alps.h
index eee59853b9ce..704f0f924307 100644
--- a/drivers/input/mouse/alps.h
+++ b/drivers/input/mouse/alps.h
@@ -17,6 +17,7 @@
 #define ALPS_PROTO_V3	3
 #define ALPS_PROTO_V4	4
 #define ALPS_PROTO_V5	5
+#define ALPS_PROTO_V6	6
 
 /**
  * struct alps_model_info - touchpad ID table