/* SPDX-License-Identifier: GPL-2.0-only */
/*
 * IBM TrackPoint PS/2 mouse driver
 *
 * Stephen Evanchik <evanchsa@gmail.com>
 */

#ifndef _TRACKPOINT_H
#define _TRACKPOINT_H

/*
 * These constants are from the TrackPoint System
 * Engineering documentation Version 4 from IBM Watson
 * research:
 *      http://wwwcssrv.almaden.ibm.com/trackpoint/download.html
 */

#define TP_COMMAND              0xE2    /* Commands start with this */

#define TP_READ_ID              0xE1    /* Sent for device identification */

/*
 * Valid first byte responses to the "Read Secondary ID" (0xE1) command.
 * 0x01 was the original IBM trackpoint, others implement very limited
 * subset of trackpoint features.
 */
#define TP_VARIANT_IBM                  0x01
#define TP_VARIANT_ALPS                 0x02
#define TP_VARIANT_ELAN                 0x03
#define TP_VARIANT_NXP                  0x04
#define TP_VARIANT_JYT_SYNAPTICS        0x05
#define TP_VARIANT_SYNAPTICS            0x06

/*
 * Commands
 */
#define TP_RECALIB              0x51    /* Recalibrate */
#define TP_POWER_DOWN           0x44    /* Can only be undone through HW reset */
#define TP_EXT_DEV              0x21    /* Determines if external device is connected (RO) */
#define TP_EXT_BTN              0x4B    /* Read extended button status */
#define TP_POR                  0x7F    /* Execute Power on Reset */
#define TP_POR_RESULTS          0x25    /* Read Power on Self test results */
#define TP_DISABLE_EXT          0x40    /* Disable external pointing device */
#define TP_ENABLE_EXT           0x41    /* Enable external pointing device */

/*
 * Mode manipulation
 */
#define TP_SET_SOFT_TRANS       0x4E    /* Set mode */
#define TP_CANCEL_SOFT_TRANS    0xB9    /* Cancel mode */
#define TP_SET_HARD_TRANS       0x45    /* Mode can only be set */


/*
 * Register oriented commands/properties
 */
#define TP_WRITE_MEM            0x81
#define TP_READ_MEM             0x80    /* Not used in this implementation */

/*
* RAM Locations for properties
 */
#define TP_SENS                 0x4A    /* Sensitivity */
#define TP_MB                   0x4C    /* Read Middle Button Status (RO) */
#define TP_INERTIA              0x4D    /* Negative Inertia */
#define TP_SPEED                0x60    /* Speed of TP Cursor */
#define TP_REACH                0x57    /* Backup for Z-axis press */
#define TP_DRAGHYS              0x58    /* Drag Hysteresis */
                                        /* (how hard it is to drag */
                                        /* with Z-axis pressed) */

#define TP_MINDRAG              0x59    /* Minimum amount of force needed */
                                        /* to trigger dragging */

#define TP_THRESH               0x5C    /* Minimum value for a Z-axis press */
#define TP_UP_THRESH            0x5A    /* Used to generate a 'click' on Z-axis */
#define TP_Z_TIME               0x5E    /* How sharp of a press */
#define TP_JENKS_CURV           0x5D    /* Minimum curvature for double click */
#define TP_DRIFT_TIME           0x5F    /* How long a 'hands off' condition */
                                        /* must last (x*107ms) for drift */
                                        /* correction to occur */

/*
 * Toggling Flag bits
 */
#define TP_TOGGLE               0x47    /* Toggle command */

#define TP_TOGGLE_MB            0x23    /* Disable/Enable Middle Button */
#define TP_MASK_MB                      0x01
#define TP_TOGGLE_EXT_DEV       0x23    /* Disable external device */
#define TP_MASK_EXT_DEV                 0x02
#define TP_TOGGLE_DRIFT         0x23    /* Drift Correction */
#define TP_MASK_DRIFT                   0x80
#define TP_TOGGLE_BURST         0x28    /* Burst Mode */
#define TP_MASK_BURST                   0x80
#define TP_TOGGLE_PTSON         0x2C    /* Press to Select */
#define TP_MASK_PTSON                   0x01
#define TP_TOGGLE_HARD_TRANS    0x2C    /* Alternate method to set Hard Transparency */
#define TP_MASK_HARD_TRANS              0x80
#define TP_TOGGLE_TWOHAND       0x2D    /* Two handed */
#define TP_MASK_TWOHAND                 0x01
#define TP_TOGGLE_STICKY_TWO    0x2D    /* Sticky two handed */
#define TP_MASK_STICKY_TWO              0x04
#define TP_TOGGLE_SKIPBACK      0x2D    /* Suppress movement after drag release */
#define TP_MASK_SKIPBACK                0x08
#define TP_TOGGLE_SOURCE_TAG    0x20    /* Bit 3 of the first packet will be set to
                                           to the origin of the packet (external or TP) */
#define TP_MASK_SOURCE_TAG              0x80
#define TP_TOGGLE_EXT_TAG       0x22    /* Bit 3 of the first packet coming from the
                                           external device will be forced to 1 */
#define TP_MASK_EXT_TAG                 0x04


/* Power on Self Test Results */
#define TP_POR_SUCCESS          0x3B

/*
 * Default power on values
 */
#define TP_DEF_SENS             0x80
#define TP_DEF_INERTIA          0x06
#define TP_DEF_SPEED            0x61
#define TP_DEF_REACH            0x0A

#define TP_DEF_DRAGHYS          0xFF
#define TP_DEF_MINDRAG          0x14

#define TP_DEF_THRESH           0x08
#define TP_DEF_UP_THRESH        0xFF
#define TP_DEF_Z_TIME           0x26
#define TP_DEF_JENKS_CURV       0x87
#define TP_DEF_DRIFT_TIME       0x05

/* Toggles */
#define TP_DEF_MB               0x00
#define TP_DEF_PTSON            0x00
#define TP_DEF_SKIPBACK         0x00
#define TP_DEF_EXT_DEV          0x00    /* 0 means enabled */
#define TP_DEF_TWOHAND          0x00
#define TP_DEF_SOURCE_TAG       0x00

#define MAKE_PS2_CMD(params, results, cmd) ((params<<12) | (results<<8) | (cmd))

struct trackpoint_data {
        u8 variant_id;
        u8 firmware_id;

        u8 sensitivity, speed, inertia, reach;
        u8 draghys, mindrag;
        u8 thresh, upthresh;
        u8 ztime, jenks;
        u8 drift_time;

        /* toggles */
        bool press_to_select;
        bool skipback;
        bool ext_dev;
};

int trackpoint_detect(struct psmouse *psmouse, bool set_properties);

#endif /* _TRACKPOINT_H */