1 files changed, 475 insertions, 0 deletions

diff --git a/drivers/input/mouse/trackpoint.c b/drivers/input/mouse/trackpoint.c
new file mode 100644
index 000000000..4a86b3e31
--- /dev/null
+++ b/drivers/input/mouse/trackpoint.c
@@ -0,0 +1,475 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Stephen Evanchik <evanchsa@gmail.com>
+ *
+ * Trademarks are the property of their respective owners.
+ */
+
+#include <linux/slab.h>
+#include <linux/delay.h>
+#include <linux/serio.h>
+#include <linux/module.h>
+#include <linux/input.h>
+#include <linux/libps2.h>
+#include <linux/proc_fs.h>
+#include <linux/uaccess.h>
+#include "psmouse.h"
+#include "trackpoint.h"
+
+static const char * const trackpoint_variants[] = {
+	[TP_VARIANT_IBM]		= "IBM",
+	[TP_VARIANT_ALPS]		= "ALPS",
+	[TP_VARIANT_ELAN]		= "Elan",
+	[TP_VARIANT_NXP]		= "NXP",
+	[TP_VARIANT_JYT_SYNAPTICS]	= "JYT_Synaptics",
+	[TP_VARIANT_SYNAPTICS]		= "Synaptics",
+};
+
+/*
+ * Power-on Reset: Resets all trackpoint parameters, including RAM values,
+ * to defaults.
+ * Returns zero on success, non-zero on failure.
+ */
+static int trackpoint_power_on_reset(struct ps2dev *ps2dev)
+{
+	u8 param[2] = { TP_POR };
+	int err;
+
+	err = ps2_command(ps2dev, param, MAKE_PS2_CMD(1, 2, TP_COMMAND));
+	if (err)
+		return err;
+
+	/* Check for success response -- 0xAA00 */
+	if (param[0] != 0xAA || param[1] != 0x00)
+		return -ENODEV;
+
+	return 0;
+}
+
+/*
+ * Device IO: read, write and toggle bit
+ */
+static int trackpoint_read(struct ps2dev *ps2dev, u8 loc, u8 *results)
+{
+	results[0] = loc;
+
+	return ps2_command(ps2dev, results, MAKE_PS2_CMD(1, 1, TP_COMMAND));
+}
+
+static int trackpoint_write(struct ps2dev *ps2dev, u8 loc, u8 val)
+{
+	u8 param[3] = { TP_WRITE_MEM, loc, val };
+
+	return ps2_command(ps2dev, param, MAKE_PS2_CMD(3, 0, TP_COMMAND));
+}
+
+static int trackpoint_toggle_bit(struct ps2dev *ps2dev, u8 loc, u8 mask)
+{
+	u8 param[3] = { TP_TOGGLE, loc, mask };
+
+	/* Bad things will happen if the loc param isn't in this range */
+	if (loc < 0x20 || loc >= 0x2F)
+		return -EINVAL;
+
+	return ps2_command(ps2dev, param, MAKE_PS2_CMD(3, 0, TP_COMMAND));
+}
+
+static int trackpoint_update_bit(struct ps2dev *ps2dev,
+				 u8 loc, u8 mask, u8 value)
+{
+	int retval;
+	u8 data;
+
+	retval = trackpoint_read(ps2dev, loc, &data);
+	if (retval)
+		return retval;
+
+	if (((data & mask) == mask) != !!value)
+		retval = trackpoint_toggle_bit(ps2dev, loc, mask);
+
+	return retval;
+}
+
+/*
+ * Trackpoint-specific attributes
+ */
+struct trackpoint_attr_data {
+	size_t field_offset;
+	u8 command;
+	u8 mask;
+	bool inverted;
+	u8 power_on_default;
+};
+
+static ssize_t trackpoint_show_int_attr(struct psmouse *psmouse,
+					void *data, char *buf)
+{
+	struct trackpoint_data *tp = psmouse->private;
+	struct trackpoint_attr_data *attr = data;
+	u8 value = *(u8 *)((void *)tp + attr->field_offset);
+
+	if (attr->inverted)
+		value = !value;
+
+	return sprintf(buf, "%u\n", value);
+}
+
+static ssize_t trackpoint_set_int_attr(struct psmouse *psmouse, void *data,
+					const char *buf, size_t count)
+{
+	struct trackpoint_data *tp = psmouse->private;
+	struct trackpoint_attr_data *attr = data;
+	u8 *field = (void *)tp + attr->field_offset;
+	u8 value;
+	int err;
+
+	err = kstrtou8(buf, 10, &value);
+	if (err)
+		return err;
+
+	*field = value;
+	err = trackpoint_write(&psmouse->ps2dev, attr->command, value);
+
+	return err ?: count;
+}
+
+#define TRACKPOINT_INT_ATTR(_name, _command, _default)				\
+	static struct trackpoint_attr_data trackpoint_attr_##_name = {		\
+		.field_offset = offsetof(struct trackpoint_data, _name),	\
+		.command = _command,						\
+		.power_on_default = _default,					\
+	};									\
+	PSMOUSE_DEFINE_ATTR(_name, S_IWUSR | S_IRUGO,				\
+			    &trackpoint_attr_##_name,				\
+			    trackpoint_show_int_attr, trackpoint_set_int_attr)
+
+static ssize_t trackpoint_set_bit_attr(struct psmouse *psmouse, void *data,
+					const char *buf, size_t count)
+{
+	struct trackpoint_data *tp = psmouse->private;
+	struct trackpoint_attr_data *attr = data;
+	bool *field = (void *)tp + attr->field_offset;
+	bool value;
+	int err;
+
+	err = kstrtobool(buf, &value);
+	if (err)
+		return err;
+
+	if (attr->inverted)
+		value = !value;
+
+	if (*field != value) {
+		*field = value;
+		err = trackpoint_toggle_bit(&psmouse->ps2dev,
+					    attr->command, attr->mask);
+	}
+
+	return err ?: count;
+}
+
+
+#define TRACKPOINT_BIT_ATTR(_name, _command, _mask, _inv, _default)	\
+static struct trackpoint_attr_data trackpoint_attr_##_name = {		\
+	.field_offset		= offsetof(struct trackpoint_data,	\
+					   _name),			\
+	.command		= _command,				\
+	.mask			= _mask,				\
+	.inverted		= _inv,					\
+	.power_on_default	= _default,				\
+	};								\
+PSMOUSE_DEFINE_ATTR(_name, S_IWUSR | S_IRUGO,				\
+		    &trackpoint_attr_##_name,				\
+		    trackpoint_show_int_attr, trackpoint_set_bit_attr)
+
+TRACKPOINT_INT_ATTR(sensitivity, TP_SENS, TP_DEF_SENS);
+TRACKPOINT_INT_ATTR(speed, TP_SPEED, TP_DEF_SPEED);
+TRACKPOINT_INT_ATTR(inertia, TP_INERTIA, TP_DEF_INERTIA);
+TRACKPOINT_INT_ATTR(reach, TP_REACH, TP_DEF_REACH);
+TRACKPOINT_INT_ATTR(draghys, TP_DRAGHYS, TP_DEF_DRAGHYS);
+TRACKPOINT_INT_ATTR(mindrag, TP_MINDRAG, TP_DEF_MINDRAG);
+TRACKPOINT_INT_ATTR(thresh, TP_THRESH, TP_DEF_THRESH);
+TRACKPOINT_INT_ATTR(upthresh, TP_UP_THRESH, TP_DEF_UP_THRESH);
+TRACKPOINT_INT_ATTR(ztime, TP_Z_TIME, TP_DEF_Z_TIME);
+TRACKPOINT_INT_ATTR(jenks, TP_JENKS_CURV, TP_DEF_JENKS_CURV);
+TRACKPOINT_INT_ATTR(drift_time, TP_DRIFT_TIME, TP_DEF_DRIFT_TIME);
+
+TRACKPOINT_BIT_ATTR(press_to_select, TP_TOGGLE_PTSON, TP_MASK_PTSON, false,
+		    TP_DEF_PTSON);
+TRACKPOINT_BIT_ATTR(skipback, TP_TOGGLE_SKIPBACK, TP_MASK_SKIPBACK, false,
+		    TP_DEF_SKIPBACK);
+TRACKPOINT_BIT_ATTR(ext_dev, TP_TOGGLE_EXT_DEV, TP_MASK_EXT_DEV, true,
+		    TP_DEF_EXT_DEV);
+
+static bool trackpoint_is_attr_available(struct psmouse *psmouse,
+					 struct attribute *attr)
+{
+	struct trackpoint_data *tp = psmouse->private;
+
+	return tp->variant_id == TP_VARIANT_IBM ||
+		attr == &psmouse_attr_sensitivity.dattr.attr ||
+		attr == &psmouse_attr_press_to_select.dattr.attr;
+}
+
+static umode_t trackpoint_is_attr_visible(struct kobject *kobj,
+					  struct attribute *attr, int n)
+{
+	struct device *dev = kobj_to_dev(kobj);
+	struct serio *serio = to_serio_port(dev);
+	struct psmouse *psmouse = serio_get_drvdata(serio);
+
+	return trackpoint_is_attr_available(psmouse, attr) ? attr->mode : 0;
+}
+
+static struct attribute *trackpoint_attrs[] = {
+	&psmouse_attr_sensitivity.dattr.attr,
+	&psmouse_attr_speed.dattr.attr,
+	&psmouse_attr_inertia.dattr.attr,
+	&psmouse_attr_reach.dattr.attr,
+	&psmouse_attr_draghys.dattr.attr,
+	&psmouse_attr_mindrag.dattr.attr,
+	&psmouse_attr_thresh.dattr.attr,
+	&psmouse_attr_upthresh.dattr.attr,
+	&psmouse_attr_ztime.dattr.attr,
+	&psmouse_attr_jenks.dattr.attr,
+	&psmouse_attr_drift_time.dattr.attr,
+	&psmouse_attr_press_to_select.dattr.attr,
+	&psmouse_attr_skipback.dattr.attr,
+	&psmouse_attr_ext_dev.dattr.attr,
+	NULL
+};
+
+static struct attribute_group trackpoint_attr_group = {
+	.is_visible	= trackpoint_is_attr_visible,
+	.attrs		= trackpoint_attrs,
+};
+
+#define TRACKPOINT_UPDATE(_power_on, _psmouse, _tp, _name)		\
+do {									\
+	struct trackpoint_attr_data *_attr = &trackpoint_attr_##_name;	\
+									\
+	if ((!_power_on || _tp->_name != _attr->power_on_default) &&	\
+	    trackpoint_is_attr_available(_psmouse,			\
+				&psmouse_attr_##_name.dattr.attr)) {	\
+		if (!_attr->mask)					\
+			trackpoint_write(&_psmouse->ps2dev,		\
+					 _attr->command, _tp->_name);	\
+		else							\
+			trackpoint_update_bit(&_psmouse->ps2dev,	\
+					_attr->command, _attr->mask,	\
+					_tp->_name);			\
+	}								\
+} while (0)
+
+#define TRACKPOINT_SET_POWER_ON_DEFAULT(_tp, _name)			\
+do {									\
+	_tp->_name = trackpoint_attr_##_name.power_on_default;		\
+} while (0)
+
+static int trackpoint_start_protocol(struct psmouse *psmouse,
+				     u8 *variant_id, u8 *firmware_id)
+{
+	u8 param[2] = { 0 };
+	int error;
+
+	error = ps2_command(&psmouse->ps2dev,
+			    param, MAKE_PS2_CMD(0, 2, TP_READ_ID));
+	if (error)
+		return error;
+
+	switch (param[0]) {
+	case TP_VARIANT_IBM:
+	case TP_VARIANT_ALPS:
+	case TP_VARIANT_ELAN:
+	case TP_VARIANT_NXP:
+	case TP_VARIANT_JYT_SYNAPTICS:
+	case TP_VARIANT_SYNAPTICS:
+		if (variant_id)
+			*variant_id = param[0];
+		if (firmware_id)
+			*firmware_id = param[1];
+		return 0;
+	}
+
+	return -ENODEV;
+}
+
+/*
+ * Write parameters to trackpad.
+ * in_power_on_state: Set to true if TP is in default / power-on state (ex. if
+ *		      power-on reset was run). If so, values will only be
+ *		      written to TP if they differ from power-on default.
+ */
+static int trackpoint_sync(struct psmouse *psmouse, bool in_power_on_state)
+{
+	struct trackpoint_data *tp = psmouse->private;
+
+	if (!in_power_on_state && tp->variant_id == TP_VARIANT_IBM) {
+		/*
+		 * Disable features that may make device unusable
+		 * with this driver.
+		 */
+		trackpoint_update_bit(&psmouse->ps2dev, TP_TOGGLE_TWOHAND,
+				      TP_MASK_TWOHAND, TP_DEF_TWOHAND);
+
+		trackpoint_update_bit(&psmouse->ps2dev, TP_TOGGLE_SOURCE_TAG,
+				      TP_MASK_SOURCE_TAG, TP_DEF_SOURCE_TAG);
+
+		trackpoint_update_bit(&psmouse->ps2dev, TP_TOGGLE_MB,
+				      TP_MASK_MB, TP_DEF_MB);
+	}
+
+	/*
+	 * These properties can be changed in this driver. Only
+	 * configure them if the values are non-default or if the TP is in
+	 * an unknown state.
+	 */
+	TRACKPOINT_UPDATE(in_power_on_state, psmouse, tp, sensitivity);
+	TRACKPOINT_UPDATE(in_power_on_state, psmouse, tp, inertia);
+	TRACKPOINT_UPDATE(in_power_on_state, psmouse, tp, speed);
+	TRACKPOINT_UPDATE(in_power_on_state, psmouse, tp, reach);
+	TRACKPOINT_UPDATE(in_power_on_state, psmouse, tp, draghys);
+	TRACKPOINT_UPDATE(in_power_on_state, psmouse, tp, mindrag);
+	TRACKPOINT_UPDATE(in_power_on_state, psmouse, tp, thresh);
+	TRACKPOINT_UPDATE(in_power_on_state, psmouse, tp, upthresh);
+	TRACKPOINT_UPDATE(in_power_on_state, psmouse, tp, ztime);
+	TRACKPOINT_UPDATE(in_power_on_state, psmouse, tp, jenks);
+	TRACKPOINT_UPDATE(in_power_on_state, psmouse, tp, drift_time);
+
+	/* toggles */
+	TRACKPOINT_UPDATE(in_power_on_state, psmouse, tp, press_to_select);
+	TRACKPOINT_UPDATE(in_power_on_state, psmouse, tp, skipback);
+	TRACKPOINT_UPDATE(in_power_on_state, psmouse, tp, ext_dev);
+
+	return 0;
+}
+
+static void trackpoint_defaults(struct trackpoint_data *tp)
+{
+	TRACKPOINT_SET_POWER_ON_DEFAULT(tp, sensitivity);
+	TRACKPOINT_SET_POWER_ON_DEFAULT(tp, speed);
+	TRACKPOINT_SET_POWER_ON_DEFAULT(tp, reach);
+	TRACKPOINT_SET_POWER_ON_DEFAULT(tp, draghys);
+	TRACKPOINT_SET_POWER_ON_DEFAULT(tp, mindrag);
+	TRACKPOINT_SET_POWER_ON_DEFAULT(tp, thresh);
+	TRACKPOINT_SET_POWER_ON_DEFAULT(tp, upthresh);
+	TRACKPOINT_SET_POWER_ON_DEFAULT(tp, ztime);
+	TRACKPOINT_SET_POWER_ON_DEFAULT(tp, jenks);
+	TRACKPOINT_SET_POWER_ON_DEFAULT(tp, drift_time);
+	TRACKPOINT_SET_POWER_ON_DEFAULT(tp, inertia);
+
+	/* toggles */
+	TRACKPOINT_SET_POWER_ON_DEFAULT(tp, press_to_select);
+	TRACKPOINT_SET_POWER_ON_DEFAULT(tp, skipback);
+	TRACKPOINT_SET_POWER_ON_DEFAULT(tp, ext_dev);
+}
+
+static void trackpoint_disconnect(struct psmouse *psmouse)
+{
+	device_remove_group(&psmouse->ps2dev.serio->dev,
+			    &trackpoint_attr_group);
+
+	kfree(psmouse->private);
+	psmouse->private = NULL;
+}
+
+static int trackpoint_reconnect(struct psmouse *psmouse)
+{
+	struct trackpoint_data *tp = psmouse->private;
+	int error;
+	bool was_reset;
+
+	error = trackpoint_start_protocol(psmouse, NULL, NULL);
+	if (error)
+		return error;
+
+	was_reset = tp->variant_id == TP_VARIANT_IBM &&
+		    trackpoint_power_on_reset(&psmouse->ps2dev) == 0;
+
+	error = trackpoint_sync(psmouse, was_reset);
+	if (error)
+		return error;
+
+	return 0;
+}
+
+int trackpoint_detect(struct psmouse *psmouse, bool set_properties)
+{
+	struct ps2dev *ps2dev = &psmouse->ps2dev;
+	struct trackpoint_data *tp;
+	u8 variant_id;
+	u8 firmware_id;
+	u8 button_info;
+	int error;
+
+	error = trackpoint_start_protocol(psmouse, &variant_id, &firmware_id);
+	if (error)
+		return error;
+
+	if (!set_properties)
+		return 0;
+
+	tp = kzalloc(sizeof(*tp), GFP_KERNEL);
+	if (!tp)
+		return -ENOMEM;
+
+	trackpoint_defaults(tp);
+	tp->variant_id = variant_id;
+	tp->firmware_id = firmware_id;
+
+	psmouse->private = tp;
+
+	psmouse->vendor = trackpoint_variants[variant_id];
+	psmouse->name = "TrackPoint";
+
+	psmouse->reconnect = trackpoint_reconnect;
+	psmouse->disconnect = trackpoint_disconnect;
+
+	if (variant_id != TP_VARIANT_IBM) {
+		/* Newer variants do not support extended button query. */
+		button_info = 0x33;
+	} else {
+		error = trackpoint_read(ps2dev, TP_EXT_BTN, &button_info);
+		if (error) {
+			psmouse_warn(psmouse,
+				     "failed to get extended button data, assuming 3 buttons\n");
+			button_info = 0x33;
+		} else if (!button_info) {
+			psmouse_warn(psmouse,
+				     "got 0 in extended button data, assuming 3 buttons\n");
+			button_info = 0x33;
+		}
+	}
+
+	if ((button_info & 0x0f) >= 3)
+		input_set_capability(psmouse->dev, EV_KEY, BTN_MIDDLE);
+
+	__set_bit(INPUT_PROP_POINTER, psmouse->dev->propbit);
+	__set_bit(INPUT_PROP_POINTING_STICK, psmouse->dev->propbit);
+
+	if (variant_id != TP_VARIANT_IBM ||
+	    trackpoint_power_on_reset(ps2dev) != 0) {
+		/*
+		 * Write defaults to TP if we did not reset the trackpoint.
+		 */
+		trackpoint_sync(psmouse, false);
+	}
+
+	error = device_add_group(&ps2dev->serio->dev, &trackpoint_attr_group);
+	if (error) {
+		psmouse_err(psmouse,
+			    "failed to create sysfs attributes, error: %d\n",
+			    error);
+		kfree(psmouse->private);
+		psmouse->private = NULL;
+		return -1;
+	}
+
+	psmouse_info(psmouse,
+		     "%s TrackPoint firmware: 0x%02x, buttons: %d/%d\n",
+		     psmouse->vendor, firmware_id,
+		     (button_info & 0xf0) >> 4, button_info & 0x0f);
+
+	return 0;
+}
+