Staging
v0.6.0
v0.6.0
https://github.com/torvalds/linux
Tip revision: 2ccdd1b13c591d306f0401d98dedc4bdcd02b421 authored by Linus Torvalds on 13 August 2023, 18:29:55 UTC
Linux 6.5-rc6
Linux 6.5-rc6
Tip revision: 2ccdd1b
trackpoint.c
// 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 = psmouse_from_serio(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;
}