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