1 files changed, 456 insertions, 0 deletions
diff --git a/drivers/input/mouse/focaltech.c b/drivers/input/mouse/focaltech.c
new file mode 100644
index 000000000..c74b99077
--- /dev/null
+++ b/drivers/input/mouse/focaltech.c
@@ -0,0 +1,456 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Focaltech TouchPad PS/2 mouse driver
+ *
+ * Copyright (c) 2014 Red Hat Inc.
+ * Copyright (c) 2014 Mathias Gottschlag <mgottschlag@gmail.com>
+ *
+ * Red Hat authors:
+ *
+ * Hans de Goede <hdegoede@redhat.com>
+ */
+
+
+#include <linux/device.h>
+#include <linux/libps2.h>
+#include <linux/input/mt.h>
+#include <linux/serio.h>
+#include <linux/slab.h>
+#include "psmouse.h"
+#include "focaltech.h"
+
+static const char * const focaltech_pnp_ids[] = {
+	"FLT0101",
+	"FLT0102",
+	"FLT0103",
+	NULL
+};
+
+/*
+ * Even if the kernel is built without support for Focaltech PS/2 touchpads (or
+ * when the real driver fails to recognize the device), we still have to detect
+ * them in order to avoid further detection attempts confusing the touchpad.
+ * This way it at least works in PS/2 mouse compatibility mode.
+ */
+int focaltech_detect(struct psmouse *psmouse, bool set_properties)
+{
+	if (!psmouse_matches_pnp_id(psmouse, focaltech_pnp_ids))
+		return -ENODEV;
+
+	if (set_properties) {
+		psmouse->vendor = "FocalTech";
+		psmouse->name = "Touchpad";
+	}
+
+	return 0;
+}
+
+#ifdef CONFIG_MOUSE_PS2_FOCALTECH
+
+/*
+ * Packet types - the numbers are not consecutive, so we might be missing
+ * something here.
+ */
+#define FOC_TOUCH 0x3 /* bitmap of active fingers */
+#define FOC_ABS 0x6 /* absolute position of one finger */
+#define FOC_REL 0x9 /* relative position of 1-2 fingers */
+
+#define FOC_MAX_FINGERS 5
+
+/*
+ * Current state of a single finger on the touchpad.
+ */
+struct focaltech_finger_state {
+	/* The touchpad has generated a touch event for the finger */
+	bool active;
+
+	/*
+	 * The touchpad has sent position data for the finger. The
+	 * flag is 0 when the finger is not active, and there is a
+	 * time between the first touch event for the finger and the
+	 * following absolute position packet for the finger where the
+	 * touchpad has declared the finger to be valid, but we do not
+	 * have any valid position yet.
+	 */
+	bool valid;
+
+	/*
+	 * Absolute position (from the bottom left corner) of the
+	 * finger.
+	 */
+	unsigned int x;
+	unsigned int y;
+};
+
+/*
+ * Description of the current state of the touchpad hardware.
+ */
+struct focaltech_hw_state {
+	/*
+	 * The touchpad tracks the positions of the fingers for us,
+	 * the array indices correspond to the finger indices returned
+	 * in the report packages.
+	 */
+	struct focaltech_finger_state fingers[FOC_MAX_FINGERS];
+
+	/*
+	 * Finger width 0-7 and 15 for a very big contact area.
+	 * 15 value stays until the finger is released.
+	 * Width is reported only in absolute packets.
+	 * Since hardware reports width only for last touching finger,
+	 * there is no need to store width for every specific finger,
+	 * so we keep only last value reported.
+	 */
+	unsigned int width;
+
+	/* True if the clickpad has been pressed. */
+	bool pressed;
+};
+
+struct focaltech_data {
+	unsigned int x_max, y_max;
+	struct focaltech_hw_state state;
+};
+
+static void focaltech_report_state(struct psmouse *psmouse)
+{
+	struct focaltech_data *priv = psmouse->private;
+	struct focaltech_hw_state *state = &priv->state;
+	struct input_dev *dev = psmouse->dev;
+	int i;
+
+	for (i = 0; i < FOC_MAX_FINGERS; i++) {
+		struct focaltech_finger_state *finger = &state->fingers[i];
+		bool active = finger->active && finger->valid;
+
+		input_mt_slot(dev, i);
+		input_mt_report_slot_state(dev, MT_TOOL_FINGER, active);
+		if (active) {
+			unsigned int clamped_x, clamped_y;
+			/*
+			 * The touchpad might report invalid data, so we clamp
+			 * the resulting values so that we do not confuse
+			 * userspace.
+			 */
+			clamped_x = clamp(finger->x, 0U, priv->x_max);
+			clamped_y = clamp(finger->y, 0U, priv->y_max);
+			input_report_abs(dev, ABS_MT_POSITION_X, clamped_x);
+			input_report_abs(dev, ABS_MT_POSITION_Y,
+					 priv->y_max - clamped_y);
+			input_report_abs(dev, ABS_TOOL_WIDTH, state->width);
+		}
+	}
+	input_mt_report_pointer_emulation(dev, true);
+
+	input_report_key(dev, BTN_LEFT, state->pressed);
+	input_sync(dev);
+}
+
+static void focaltech_process_touch_packet(struct psmouse *psmouse,
+					   unsigned char *packet)
+{
+	struct focaltech_data *priv = psmouse->private;
+	struct focaltech_hw_state *state = &priv->state;
+	unsigned char fingers = packet[1];
+	int i;
+
+	state->pressed = (packet[0] >> 4) & 1;
+
+	/* the second byte contains a bitmap of all fingers touching the pad */
+	for (i = 0; i < FOC_MAX_FINGERS; i++) {
+		state->fingers[i].active = fingers & 0x1;
+		if (!state->fingers[i].active) {
+			/*
+			 * Even when the finger becomes active again, we still
+			 * will have to wait for the first valid position.
+			 */
+			state->fingers[i].valid = false;
+		}
+		fingers >>= 1;
+	}
+}
+
+static void focaltech_process_abs_packet(struct psmouse *psmouse,
+					 unsigned char *packet)
+{
+	struct focaltech_data *priv = psmouse->private;
+	struct focaltech_hw_state *state = &priv->state;
+	unsigned int finger;
+
+	finger = (packet[1] >> 4) - 1;
+	if (finger >= FOC_MAX_FINGERS) {
+		psmouse_err(psmouse, "Invalid finger in abs packet: %d\n",
+			    finger);
+		return;
+	}
+
+	state->pressed = (packet[0] >> 4) & 1;
+
+	state->fingers[finger].x = ((packet[1] & 0xf) << 8) | packet[2];
+	state->fingers[finger].y = (packet[3] << 8) | packet[4];
+	state->width = packet[5] >> 4;
+	state->fingers[finger].valid = true;
+}
+
+static void focaltech_process_rel_packet(struct psmouse *psmouse,
+					 unsigned char *packet)
+{
+	struct focaltech_data *priv = psmouse->private;
+	struct focaltech_hw_state *state = &priv->state;
+	int finger1, finger2;
+
+	state->pressed = packet[0] >> 7;
+	finger1 = ((packet[0] >> 4) & 0x7) - 1;
+	if (finger1 < FOC_MAX_FINGERS) {
+		state->fingers[finger1].x += (s8)packet[1];
+		state->fingers[finger1].y += (s8)packet[2];
+	} else {
+		psmouse_err(psmouse, "First finger in rel packet invalid: %d\n",
+			    finger1);
+	}
+
+	/*
+	 * If there is an odd number of fingers, the last relative
+	 * packet only contains one finger. In this case, the second
+	 * finger index in the packet is 0 (we subtract 1 in the lines
+	 * above to create array indices, so the finger will overflow
+	 * and be above FOC_MAX_FINGERS).
+	 */
+	finger2 = ((packet[3] >> 4) & 0x7) - 1;
+	if (finger2 < FOC_MAX_FINGERS) {
+		state->fingers[finger2].x += (s8)packet[4];
+		state->fingers[finger2].y += (s8)packet[5];
+	}
+}
+
+static void focaltech_process_packet(struct psmouse *psmouse)
+{
+	unsigned char *packet = psmouse->packet;
+
+	switch (packet[0] & 0xf) {
+	case FOC_TOUCH:
+		focaltech_process_touch_packet(psmouse, packet);
+		break;
+
+	case FOC_ABS:
+		focaltech_process_abs_packet(psmouse, packet);
+		break;
+
+	case FOC_REL:
+		focaltech_process_rel_packet(psmouse, packet);
+		break;
+
+	default:
+		psmouse_err(psmouse, "Unknown packet type: %02x\n", packet[0]);
+		break;
+	}
+
+	focaltech_report_state(psmouse);
+}
+
+static psmouse_ret_t focaltech_process_byte(struct psmouse *psmouse)
+{
+	if (psmouse->pktcnt >= 6) { /* Full packet received */
+		focaltech_process_packet(psmouse);
+		return PSMOUSE_FULL_PACKET;
+	}
+
+	/*
+	 * We might want to do some validation of the data here, but
+	 * we do not know the protocol well enough
+	 */
+	return PSMOUSE_GOOD_DATA;
+}
+
+static int focaltech_switch_protocol(struct psmouse *psmouse)
+{
+	struct ps2dev *ps2dev = &psmouse->ps2dev;
+	unsigned char param[3];
+
+	param[0] = 0;
+	if (ps2_command(ps2dev, param, 0x10f8))
+		return -EIO;
+
+	if (ps2_command(ps2dev, param, 0x10f8))
+		return -EIO;
+
+	if (ps2_command(ps2dev, param, 0x10f8))
+		return -EIO;
+
+	param[0] = 1;
+	if (ps2_command(ps2dev, param, 0x10f8))
+		return -EIO;
+
+	if (ps2_command(ps2dev, param, PSMOUSE_CMD_SETSCALE11))
+		return -EIO;
+
+	if (ps2_command(ps2dev, param, PSMOUSE_CMD_ENABLE))
+		return -EIO;
+
+	return 0;
+}
+
+static void focaltech_reset(struct psmouse *psmouse)
+{
+	ps2_command(&psmouse->ps2dev, NULL, PSMOUSE_CMD_RESET_DIS);
+	psmouse_reset(psmouse);
+}
+
+static void focaltech_disconnect(struct psmouse *psmouse)
+{
+	focaltech_reset(psmouse);
+	kfree(psmouse->private);
+	psmouse->private = NULL;
+}
+
+static int focaltech_reconnect(struct psmouse *psmouse)
+{
+	int error;
+
+	focaltech_reset(psmouse);
+
+	error = focaltech_switch_protocol(psmouse);
+	if (error) {
+		psmouse_err(psmouse, "Unable to initialize the device\n");
+		return error;
+	}
+
+	return 0;
+}
+
+static void focaltech_set_input_params(struct psmouse *psmouse)
+{
+	struct input_dev *dev = psmouse->dev;
+	struct focaltech_data *priv = psmouse->private;
+
+	/*
+	 * Undo part of setup done for us by psmouse core since touchpad
+	 * is not a relative device.
+	 */
+	__clear_bit(EV_REL, dev->evbit);
+	__clear_bit(REL_X, dev->relbit);
+	__clear_bit(REL_Y, dev->relbit);
+	__clear_bit(BTN_RIGHT, dev->keybit);
+	__clear_bit(BTN_MIDDLE, dev->keybit);
+
+	/*
+	 * Now set up our capabilities.
+	 */
+	__set_bit(EV_ABS, dev->evbit);
+	input_set_abs_params(dev, ABS_MT_POSITION_X, 0, priv->x_max, 0, 0);
+	input_set_abs_params(dev, ABS_MT_POSITION_Y, 0, priv->y_max, 0, 0);
+	input_set_abs_params(dev, ABS_TOOL_WIDTH, 0, 15, 0, 0);
+	input_mt_init_slots(dev, 5, INPUT_MT_POINTER);
+	__set_bit(INPUT_PROP_BUTTONPAD, dev->propbit);
+}
+
+static int focaltech_read_register(struct ps2dev *ps2dev, int reg,
+				   unsigned char *param)
+{
+	if (ps2_command(ps2dev, param, PSMOUSE_CMD_SETSCALE11))
+		return -EIO;
+
+	param[0] = 0;
+	if (ps2_command(ps2dev, param, PSMOUSE_CMD_SETRES))
+		return -EIO;
+
+	if (ps2_command(ps2dev, param, PSMOUSE_CMD_SETRES))
+		return -EIO;
+
+	if (ps2_command(ps2dev, param, PSMOUSE_CMD_SETRES))
+		return -EIO;
+
+	param[0] = reg;
+	if (ps2_command(ps2dev, param, PSMOUSE_CMD_SETRES))
+		return -EIO;
+
+	if (ps2_command(ps2dev, param, PSMOUSE_CMD_GETINFO))
+		return -EIO;
+
+	return 0;
+}
+
+static int focaltech_read_size(struct psmouse *psmouse)
+{
+	struct ps2dev *ps2dev = &psmouse->ps2dev;
+	struct focaltech_data *priv = psmouse->private;
+	char param[3];
+
+	if (focaltech_read_register(ps2dev, 2, param))
+		return -EIO;
+
+	/* not sure whether this is 100% correct */
+	priv->x_max = (unsigned char)param[1] * 128;
+	priv->y_max = (unsigned char)param[2] * 128;
+
+	return 0;
+}
+
+static void focaltech_set_resolution(struct psmouse *psmouse,
+				     unsigned int resolution)
+{
+	/* not supported yet */
+}
+
+static void focaltech_set_rate(struct psmouse *psmouse, unsigned int rate)
+{
+	/* not supported yet */
+}
+
+static void focaltech_set_scale(struct psmouse *psmouse,
+				enum psmouse_scale scale)
+{
+	/* not supported yet */
+}
+
+int focaltech_init(struct psmouse *psmouse)
+{
+	struct focaltech_data *priv;
+	int error;
+
+	psmouse->private = priv = kzalloc(sizeof(struct focaltech_data),
+					  GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	focaltech_reset(psmouse);
+
+	error = focaltech_read_size(psmouse);
+	if (error) {
+		psmouse_err(psmouse,
+			    "Unable to read the size of the touchpad\n");
+		goto fail;
+	}
+
+	error = focaltech_switch_protocol(psmouse);
+	if (error) {
+		psmouse_err(psmouse, "Unable to initialize the device\n");
+		goto fail;
+	}
+
+	focaltech_set_input_params(psmouse);
+
+	psmouse->protocol_handler = focaltech_process_byte;
+	psmouse->pktsize = 6;
+	psmouse->disconnect = focaltech_disconnect;
+	psmouse->reconnect = focaltech_reconnect;
+	psmouse->cleanup = focaltech_reset;
+	/* resync is not supported yet */
+	psmouse->resync_time = 0;
+	/*
+	 * rate/resolution/scale changes are not supported yet, and
+	 * the generic implementations of these functions seem to
+	 * confuse some touchpads
+	 */
+	psmouse->set_resolution = focaltech_set_resolution;
+	psmouse->set_rate = focaltech_set_rate;
+	psmouse->set_scale = focaltech_set_scale;
+
+	return 0;
+
+fail:
+	focaltech_reset(psmouse);
+	kfree(priv);
+	return error;
+}
+#endif /* CONFIG_MOUSE_PS2_FOCALTECH */