/* SPDX-License-Identifier: GPL-2.0-only */
/*
 * Elantech Touchpad driver (v6)
 *
 * Copyright (C) 2007-2009 Arjan Opmeer <arjan@opmeer.net>
 *
 * Trademarks are the property of their respective owners.
 */

#ifndef _ELANTECH_H
#define _ELANTECH_H

/*
 * Command values for Synaptics style queries
 */
#define ETP_FW_ID_QUERY                 0x00
#define ETP_FW_VERSION_QUERY            0x01
#define ETP_CAPABILITIES_QUERY          0x02
#define ETP_SAMPLE_QUERY                0x03
#define ETP_RESOLUTION_QUERY            0x04
#define ETP_ICBODY_QUERY                0x05

/*
 * Command values for register reading or writing
 */
#define ETP_REGISTER_READ               0x10
#define ETP_REGISTER_WRITE              0x11
#define ETP_REGISTER_READWRITE          0x00

/*
 * Hardware version 2 custom PS/2 command value
 */
#define ETP_PS2_CUSTOM_COMMAND          0xf8

/*
 * Times to retry a ps2_command and millisecond delay between tries
 */
#define ETP_PS2_COMMAND_TRIES           3
#define ETP_PS2_COMMAND_DELAY           500

/*
 * Times to try to read back a register and millisecond delay between tries
 */
#define ETP_READ_BACK_TRIES             5
#define ETP_READ_BACK_DELAY             2000

/*
 * Register bitmasks for hardware version 1
 */
#define ETP_R10_ABSOLUTE_MODE           0x04
#define ETP_R11_4_BYTE_MODE             0x02

/*
 * Capability bitmasks
 */
#define ETP_CAP_HAS_ROCKER              0x04

/*
 * One hard to find application note states that X axis range is 0 to 576
 * and Y axis range is 0 to 384 for harware version 1.
 * Edge fuzz might be necessary because of bezel around the touchpad
 */
#define ETP_EDGE_FUZZ_V1                32

#define ETP_XMIN_V1                     (  0 + ETP_EDGE_FUZZ_V1)
#define ETP_XMAX_V1                     (576 - ETP_EDGE_FUZZ_V1)
#define ETP_YMIN_V1                     (  0 + ETP_EDGE_FUZZ_V1)
#define ETP_YMAX_V1                     (384 - ETP_EDGE_FUZZ_V1)

/*
 * The resolution for older v2 hardware doubled.
 * (newer v2's firmware provides command so we can query)
 */
#define ETP_XMIN_V2                     0
#define ETP_XMAX_V2                     1152
#define ETP_YMIN_V2                     0
#define ETP_YMAX_V2                     768

#define ETP_PMIN_V2                     0
#define ETP_PMAX_V2                     255
#define ETP_WMIN_V2                     0
#define ETP_WMAX_V2                     15

/*
 * v3 hardware has 2 kinds of packet types,
 * v4 hardware has 3.
 */
#define PACKET_UNKNOWN                  0x01
#define PACKET_DEBOUNCE                 0x02
#define PACKET_V3_HEAD                  0x03
#define PACKET_V3_TAIL                  0x04
#define PACKET_V4_HEAD                  0x05
#define PACKET_V4_MOTION                0x06
#define PACKET_V4_STATUS                0x07
#define PACKET_TRACKPOINT               0x08

/*
 * track up to 5 fingers for v4 hardware
 */
#define ETP_MAX_FINGERS                 5

/*
 * weight value for v4 hardware
 */
#define ETP_WEIGHT_VALUE                5

/*
 * Bus information on 3rd byte of query ETP_RESOLUTION_QUERY(0x04)
 */
#define ETP_BUS_PS2_ONLY                0
#define ETP_BUS_SMB_ALERT_ONLY          1
#define ETP_BUS_SMB_HST_NTFY_ONLY       2
#define ETP_BUS_PS2_SMB_ALERT           3
#define ETP_BUS_PS2_SMB_HST_NTFY        4

/*
 * New ICs are either using SMBus Host Notify or just plain PS2.
 *
 * ETP_FW_VERSION_QUERY is:
 * Byte 1:
 *  - bit 0..3: IC BODY
 * Byte 2:
 *  - bit 4: HiddenButton
 *  - bit 5: PS2_SMBUS_NOTIFY
 *  - bit 6: PS2CRCCheck
 */
#define ETP_NEW_IC_SMBUS_HOST_NOTIFY(fw_version)        \
                ((((fw_version) & 0x0f2000) == 0x0f2000) && \
                 ((fw_version) & 0x0000ff) > 0)

/*
 * The base position for one finger, v4 hardware
 */
struct finger_pos {
        unsigned int x;
        unsigned int y;
};

struct elantech_device_info {
        unsigned char capabilities[3];
        unsigned char samples[3];
        unsigned char debug;
        unsigned char hw_version;
        unsigned char pattern;
        unsigned int fw_version;
        unsigned int ic_version;
        unsigned int product_id;
        unsigned int x_min;
        unsigned int y_min;
        unsigned int x_max;
        unsigned int y_max;
        unsigned int x_res;
        unsigned int y_res;
        unsigned int x_traces;
        unsigned int y_traces;
        unsigned int width;
        unsigned int bus;
        bool paritycheck;
        bool jumpy_cursor;
        bool reports_pressure;
        bool crc_enabled;
        bool set_hw_resolution;
        bool has_trackpoint;
        bool has_middle_button;
        int (*send_cmd)(struct psmouse *psmouse, unsigned char c,
                        unsigned char *param);
};

struct elantech_data {
        struct input_dev *tp_dev;       /* Relative device for trackpoint */
        char tp_phys[32];
        unsigned char reg_07;
        unsigned char reg_10;
        unsigned char reg_11;
        unsigned char reg_20;
        unsigned char reg_21;
        unsigned char reg_22;
        unsigned char reg_23;
        unsigned char reg_24;
        unsigned char reg_25;
        unsigned char reg_26;
        unsigned int single_finger_reports;
        unsigned int y_max;
        unsigned int width;
        struct finger_pos mt[ETP_MAX_FINGERS];
        unsigned char parity[256];
        struct elantech_device_info info;
        void (*original_set_rate)(struct psmouse *psmouse, unsigned int rate);
};

int elantech_detect(struct psmouse *psmouse, bool set_properties);
int elantech_init_ps2(struct psmouse *psmouse);

#ifdef CONFIG_MOUSE_PS2_ELANTECH
int elantech_init(struct psmouse *psmouse);
#else
static inline int elantech_init(struct psmouse *psmouse)
{
        return -ENOSYS;
}
#endif /* CONFIG_MOUSE_PS2_ELANTECH */

int elantech_init_smbus(struct psmouse *psmouse);

#endif