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// SPDX-License-Identifier: GPL-2.0+

/*
 * Quirks for I2C-HID devices that do not supply proper descriptors
 *
 * Copyright (c) 2018 Julian Sax <jsbc@gmx.de>
 *
 */

#include <linux/types.h>
#include <linux/dmi.h>
#include <linux/mod_devicetable.h>

#include "i2c-hid.h"


struct i2c_hid_desc_override {
	union {
		struct i2c_hid_desc *i2c_hid_desc;
		uint8_t             *i2c_hid_desc_buffer;
	};
	uint8_t              *hid_report_desc;
	unsigned int          hid_report_desc_size;
	uint8_t              *i2c_name;
};


/*
 * descriptors for the SIPODEV SP1064 touchpad
 *
 * This device does not supply any descriptors and on windows a filter
 * driver operates between the i2c-hid layer and the device and injects
 * these descriptors when the device is prompted. The descriptors were
 * extracted by listening to the i2c-hid traffic that occurs between the
 * windows filter driver and the windows i2c-hid driver.
 */

static const struct i2c_hid_desc_override sipodev_desc = {
	.i2c_hid_desc_buffer = (uint8_t [])
	{0x1e, 0x00,                  /* Length of descriptor                 */
	 0x00, 0x01,                  /* Version of descriptor                */
	 0xdb, 0x01,                  /* Length of report descriptor          */
	 0x21, 0x00,                  /* Location of report descriptor        */
	 0x24, 0x00,                  /* Location of input report             */
	 0x1b, 0x00,                  /* Max input report length              */
	 0x25, 0x00,                  /* Location of output report            */
	 0x11, 0x00,                  /* Max output report length             */
	 0x22, 0x00,                  /* Location of command register         */
	 0x23, 0x00,                  /* Location of data register            */
	 0x11, 0x09,                  /* Vendor ID                            */
	 0x88, 0x52,                  /* Product ID                           */
	 0x06, 0x00,                  /* Version ID                           */
	 0x00, 0x00, 0x00, 0x00       /* Reserved                             */
	},

	.hid_report_desc = (uint8_t [])
	{0x05, 0x01,                  /* Usage Page (Desktop),                */
	 0x09, 0x02,                  /* Usage (Mouse),                       */
	 0xA1, 0x01,                  /* Collection (Application),            */
	 0x85, 0x01,                  /*     Report ID (1),                   */
	 0x09, 0x01,                  /*     Usage (Pointer),                 */
	 0xA1, 0x00,                  /*     Collection (Physical),           */
	 0x05, 0x09,                  /*         Usage Page (Button),         */
	 0x19, 0x01,                  /*         Usage Minimum (01h),         */
	 0x29, 0x02,                  /*         Usage Maximum (02h),         */
	 0x25, 0x01,                  /*         Logical Maximum (1),         */
	 0x75, 0x01,                  /*         Report Size (1),             */
	 0x95, 0x02,                  /*         Report Count (2),            */
	 0x81, 0x02,                  /*         Input (Variable),            */
	 0x95, 0x06,                  /*         Report Count (6),            */
	 0x81, 0x01,                  /*         Input (Constant),            */
	 0x05, 0x01,                  /*         Usage Page (Desktop),        */
	 0x09, 0x30,                  /*         Usage (X),                   */
	 0x09, 0x31,                  /*         Usage (Y),                   */
	 0x15, 0x81,                  /*         Logical Minimum (-127),      */
	 0x25, 0x7F,                  /*         Logical Maximum (127),       */
	 0x75, 0x08,                  /*         Report Size (8),             */
	 0x95, 0x02,                  /*         Report Count (2),            */
	 0x81, 0x06,                  /*         Input (Variable, Relative),  */
	 0xC0,                        /*     End Collection,                  */
	 0xC0,                        /* End Collection,                      */
	 0x05, 0x0D,                  /* Usage Page (Digitizer),              */
	 0x09, 0x05,                  /* Usage (Touchpad),                    */
	 0xA1, 0x01,                  /* Collection (Application),            */
	 0x85, 0x04,                  /*     Report ID (4),                   */
	 0x05, 0x0D,                  /*     Usage Page (Digitizer),          */
	 0x09, 0x22,                  /*     Usage (Finger),                  */
	 0xA1, 0x02,                  /*     Collection (Logical),            */
	 0x15, 0x00,                  /*         Logical Minimum (0),         */
	 0x25, 0x01,                  /*         Logical Maximum (1),         */
	 0x09, 0x47,                  /*         Usage (Touch Valid),         */
	 0x09, 0x42,                  /*         Usage (Tip Switch),          */
	 0x95, 0x02,                  /*         Report Count (2),            */
	 0x75, 0x01,                  /*         Report Size (1),             */
	 0x81, 0x02,                  /*         Input (Variable),            */
	 0x95, 0x01,                  /*         Report Count (1),            */
	 0x75, 0x03,                  /*         Report Size (3),             */
	 0x25, 0x05,                  /*         Logical Maximum (5),         */
	 0x09, 0x51,                  /*         Usage (Contact Identifier),  */
	 0x81, 0x02,                  /*         Input (Variable),            */
	 0x75, 0x01,                  /*         Report Size (1),             */
	 0x95, 0x03,                  /*         Report Count (3),            */
	 0x81, 0x03,                  /*         Input (Constant, Variable),  */
	 0x05, 0x01,                  /*         Usage Page (Desktop),        */
	 0x26, 0x44, 0x0A,            /*         Logical Maximum (2628),      */
	 0x75, 0x10,                  /*         Report Size (16),            */
	 0x55, 0x0E,                  /*         Unit Exponent (14),          */
	 0x65, 0x11,                  /*         Unit (Centimeter),           */
	 0x09, 0x30,                  /*         Usage (X),                   */
	 0x46, 0x1A, 0x04,            /*         Physical Maximum (1050),     */
	 0x95, 0x01,                  /*         Report Count (1),            */
	 0x81, 0x02,                  /*         Input (Variable),            */
	 0x46, 0xBC, 0x02,            /*         Physical Maximum (700),      */
	 0x26, 0x34, 0x05,            /*         Logical Maximum (1332),      */
	 0x09, 0x31,                  /*         Usage (Y),                   */
	 0x81, 0x02,                  /*         Input (Variable),            */
	 0xC0,                        /*     End Collection,                  */
	 0x05, 0x0D,                  /*     Usage Page (Digitizer),          */
	 0x09, 0x22,                  /*     Usage (Finger),                  */
	 0xA1, 0x02,                  /*     Collection (Logical),            */
	 0x25, 0x01,                  /*         Logical Maximum (1),         */
	 0x09, 0x47,                  /*         Usage (Touch Valid),         */
	 0x09, 0x42,                  /*         Usage (Tip Switch),          */
	 0x95, 0x02,                  /*         Report Count (2),            */
	 0x75, 0x01,                  /*         Report Size (1),             */
	 0x81, 0x02,                  /*         Input (Variable),            */
	 0x95, 0x01,                  /*         Report Count (1),            */
	 0x75, 0x03,                  /*         Report Size (3),             */
	 0x25, 0x05,                  /*         Logical Maximum (5),         */
	 0x09, 0x51,                  /*         Usage (Contact Identifier),  */
	 0x81, 0x02,                  /*         Input (Variable),            */
	 0x75, 0x01,                  /*         Report Size (1),             */
	 0x95, 0x03,                  /*         Report Count (3),            */
	 0x81, 0x03,                  /*         Input (Constant, Variable),  */
	 0x05, 0x01,                  /*         Usage Page (Desktop),        */
	 0x26, 0x44, 0x0A,            /*         Logical Maximum (2628),      */
	 0x75, 0x10,                  /*         Report Size (16),            */
	 0x09, 0x30,                  /*         Usage (X),                   */
	 0x46, 0x1A, 0x04,            /*         Physical Maximum (1050),     */
	 0x95, 0x01,                  /*         Report Count (1),            */
	 0x81, 0x02,                  /*         Input (Variable),            */
	 0x46, 0xBC, 0x02,            /*         Physical Maximum (700),      */
	 0x26, 0x34, 0x05,            /*         Logical Maximum (1332),      */
	 0x09, 0x31,                  /*         Usage (Y),                   */
	 0x81, 0x02,                  /*         Input (Variable),            */
	 0xC0,                        /*     End Collection,                  */
	 0x05, 0x0D,                  /*     Usage Page (Digitizer),          */
	 0x09, 0x22,                  /*     Usage (Finger),                  */
	 0xA1, 0x02,                  /*     Collection (Logical),            */
	 0x25, 0x01,                  /*         Logical Maximum (1),         */
	 0x09, 0x47,                  /*         Usage (Touch Valid),         */
	 0x09, 0x42,                  /*         Usage (Tip Switch),          */
	 0x95, 0x02,                  /*         Report Count (2),            */
	 0x75, 0x01,                  /*         Report Size (1),             */
	 0x81, 0x02,                  /*         Input (Variable),            */
	 0x95, 0x01,                  /*         Report Count (1),            */
	 0x75, 0x03,                  /*         Report Size (3),             */
	 0x25, 0x05,                  /*         Logical Maximum (5),         */
	 0x09, 0x51,                  /*         Usage (Contact Identifier),  */
	 0x81, 0x02,                  /*         Input (Variable),            */
	 0x75, 0x01,                  /*         Report Size (1),             */
	 0x95, 0x03,                  /*         Report Count (3),            */
	 0x81, 0x03,                  /*         Input (Constant, Variable),  */
	 0x05, 0x01,                  /*         Usage Page (Desktop),        */
	 0x26, 0x44, 0x0A,            /*         Logical Maximum (2628),      */
	 0x75, 0x10,                  /*         Report Size (16),            */
	 0x09, 0x30,                  /*         Usage (X),                   */
	 0x46, 0x1A, 0x04,            /*         Physical Maximum (1050),     */
	 0x95, 0x01,                  /*         Report Count (1),            */
	 0x81, 0x02,                  /*         Input (Variable),            */
	 0x46, 0xBC, 0x02,            /*         Physical Maximum (700),      */
	 0x26, 0x34, 0x05,            /*         Logical Maximum (1332),      */
	 0x09, 0x31,                  /*         Usage (Y),                   */
	 0x81, 0x02,                  /*         Input (Variable),            */
	 0xC0,                        /*     End Collection,                  */
	 0x05, 0x0D,                  /*     Usage Page (Digitizer),          */
	 0x09, 0x22,                  /*     Usage (Finger),                  */
	 0xA1, 0x02,                  /*     Collection (Logical),            */
	 0x25, 0x01,                  /*         Logical Maximum (1),         */
	 0x09, 0x47,                  /*         Usage (Touch Valid),         */
	 0x09, 0x42,                  /*         Usage (Tip Switch),          */
	 0x95, 0x02,                  /*         Report Count (2),            */
	 0x75, 0x01,                  /*         Report Size (1),             */
	 0x81, 0x02,                  /*         Input (Variable),            */
	 0x95, 0x01,                  /*         Report Count (1),            */
	 0x75, 0x03,                  /*         Report Size (3),             */
	 0x25, 0x05,                  /*         Logical Maximum (5),         */
	 0x09, 0x51,                  /*         Usage (Contact Identifier),  */
	 0x81, 0x02,                  /*         Input (Variable),            */
	 0x75, 0x01,                  /*         Report Size (1),             */
	 0x95, 0x03,                  /*         Report Count (3),            */
	 0x81, 0x03,                  /*         Input (Constant, Variable),  */
	 0x05, 0x01,                  /*         Usage Page (Desktop),        */
	 0x26, 0x44, 0x0A,            /*         Logical Maximum (2628),      */
	 0x75, 0x10,                  /*         Report Size (16),            */
	 0x09, 0x30,                  /*         Usage (X),                   */
	 0x46, 0x1A, 0x04,            /*         Physical Maximum (1050),     */
	 0x95, 0x01,                  /*         Report Count (1),            */
	 0x81, 0x02,                  /*         Input (Variable),            */
	 0x46, 0xBC, 0x02,            /*         Physical Maximum (700),      */
	 0x26, 0x34, 0x05,            /*         Logical Maximum (1332),      */
	 0x09, 0x31,                  /*         Usage (Y),                   */
	 0x81, 0x02,                  /*         Input (Variable),            */
	 0xC0,                        /*     End Collection,                  */
	 0x05, 0x0D,                  /*     Usage Page (Digitizer),          */
	 0x55, 0x0C,                  /*     Unit Exponent (12),              */
	 0x66, 0x01, 0x10,            /*     Unit (Seconds),                  */
	 0x47, 0xFF, 0xFF, 0x00, 0x00,/*     Physical Maximum (65535),        */
	 0x27, 0xFF, 0xFF, 0x00, 0x00,/*     Logical Maximum (65535),         */
	 0x75, 0x10,                  /*     Report Size (16),                */
	 0x95, 0x01,                  /*     Report Count (1),                */
	 0x09, 0x56,                  /*     Usage (Scan Time),               */
	 0x81, 0x02,                  /*     Input (Variable),                */
	 0x09, 0x54,                  /*     Usage (Contact Count),           */
	 0x25, 0x7F,                  /*     Logical Maximum (127),           */
	 0x75, 0x08,                  /*     Report Size (8),                 */
	 0x81, 0x02,                  /*     Input (Variable),                */
	 0x05, 0x09,                  /*     Usage Page (Button),             */
	 0x09, 0x01,                  /*     Usage (01h),                     */
	 0x25, 0x01,                  /*     Logical Maximum (1),             */
	 0x75, 0x01,                  /*     Report Size (1),                 */
	 0x95, 0x01,                  /*     Report Count (1),                */
	 0x81, 0x02,                  /*     Input (Variable),                */
	 0x95, 0x07,                  /*     Report Count (7),                */
	 0x81, 0x03,                  /*     Input (Constant, Variable),      */
	 0x05, 0x0D,                  /*     Usage Page (Digitizer),          */
	 0x85, 0x02,                  /*     Report ID (2),                   */
	 0x09, 0x55,                  /*     Usage (Contact Count Maximum),   */
	 0x09, 0x59,                  /*     Usage (59h),                     */
	 0x75, 0x04,                  /*     Report Size (4),                 */
	 0x95, 0x02,                  /*     Report Count (2),                */
	 0x25, 0x0F,                  /*     Logical Maximum (15),            */
	 0xB1, 0x02,                  /*     Feature (Variable),              */
	 0x05, 0x0D,                  /*     Usage Page (Digitizer),          */
	 0x85, 0x07,                  /*     Report ID (7),                   */
	 0x09, 0x60,                  /*     Usage (60h),                     */
	 0x75, 0x01,                  /*     Report Size (1),                 */
	 0x95, 0x01,                  /*     Report Count (1),                */
	 0x25, 0x01,                  /*     Logical Maximum (1),             */
	 0xB1, 0x02,                  /*     Feature (Variable),              */
	 0x95, 0x07,                  /*     Report Count (7),                */
	 0xB1, 0x03,                  /*     Feature (Constant, Variable),    */
	 0x85, 0x06,                  /*     Report ID (6),                   */
	 0x06, 0x00, 0xFF,            /*     Usage Page (FF00h),              */
	 0x09, 0xC5,                  /*     Usage (C5h),                     */
	 0x26, 0xFF, 0x00,            /*     Logical Maximum (255),           */
	 0x75, 0x08,                  /*     Report Size (8),                 */
	 0x96, 0x00, 0x01,            /*     Report Count (256),              */
	 0xB1, 0x02,                  /*     Feature (Variable),              */
	 0xC0,                        /* End Collection,                      */
	 0x06, 0x00, 0xFF,            /* Usage Page (FF00h),                  */
	 0x09, 0x01,                  /* Usage (01h),                         */
	 0xA1, 0x01,                  /* Collection (Application),            */
	 0x85, 0x0D,                  /*     Report ID (13),                  */
	 0x26, 0xFF, 0x00,            /*     Logical Maximum (255),           */
	 0x19, 0x01,                  /*     Usage Minimum (01h),             */
	 0x29, 0x02,                  /*     Usage Maximum (02h),             */
	 0x75, 0x08,                  /*     Report Size (8),                 */
	 0x95, 0x02,                  /*     Report Count (2),                */
	 0xB1, 0x02,                  /*     Feature (Variable),              */
	 0xC0,                        /* End Collection,                      */
	 0x05, 0x0D,                  /* Usage Page (Digitizer),              */
	 0x09, 0x0E,                  /* Usage (Configuration),               */
	 0xA1, 0x01,                  /* Collection (Application),            */
	 0x85, 0x03,                  /*     Report ID (3),                   */
	 0x09, 0x22,                  /*     Usage (Finger),                  */
	 0xA1, 0x02,                  /*     Collection (Logical),            */
	 0x09, 0x52,                  /*         Usage (Device Mode),         */
	 0x25, 0x0A,                  /*         Logical Maximum (10),        */
	 0x95, 0x01,                  /*         Report Count (1),            */
	 0xB1, 0x02,                  /*         Feature (Variable),          */
	 0xC0,                        /*     End Collection,                  */
	 0x09, 0x22,                  /*     Usage (Finger),                  */
	 0xA1, 0x00,                  /*     Collection (Physical),           */
	 0x85, 0x05,                  /*         Report ID (5),               */
	 0x09, 0x57,                  /*         Usage (57h),                 */
	 0x09, 0x58,                  /*         Usage (58h),                 */
	 0x75, 0x01,                  /*         Report Size (1),             */
	 0x95, 0x02,                  /*         Report Count (2),            */
	 0x25, 0x01,                  /*         Logical Maximum (1),         */
	 0xB1, 0x02,                  /*         Feature (Variable),          */
	 0x95, 0x06,                  /*         Report Count (6),            */
	 0xB1, 0x03,                  /*         Feature (Constant, Variable),*/
	 0xC0,                        /*     End Collection,                  */
	 0xC0                         /* End Collection                       */
	},
	.hid_report_desc_size = 475,
	.i2c_name = "SYNA3602:00"
};


static const struct dmi_system_id i2c_hid_dmi_desc_override_table[] = {
	{
		.ident = "Teclast F6 Pro",
		.matches = {
			DMI_EXACT_MATCH(DMI_SYS_VENDOR, "TECLAST"),
			DMI_EXACT_MATCH(DMI_PRODUCT_NAME, "F6 Pro"),
		},
		.driver_data = (void *)&sipodev_desc
	},
	{
		.ident = "Teclast F7",
		.matches = {
			DMI_EXACT_MATCH(DMI_SYS_VENDOR, "TECLAST"),
			DMI_EXACT_MATCH(DMI_PRODUCT_NAME, "F7"),
		},
		.driver_data = (void *)&sipodev_desc
	},
	{
		.ident = "Trekstor Primebook C13",
		.matches = {
			DMI_EXACT_MATCH(DMI_SYS_VENDOR, "TREKSTOR"),
			DMI_EXACT_MATCH(DMI_PRODUCT_NAME, "Primebook C13"),
		},
		.driver_data = (void *)&sipodev_desc
	},
	{
		.ident = "Trekstor Primebook C11",
		.matches = {
			DMI_EXACT_MATCH(DMI_SYS_VENDOR, "TREKSTOR"),
			DMI_EXACT_MATCH(DMI_PRODUCT_NAME, "Primebook C11"),
		},
		.driver_data = (void *)&sipodev_desc
	},
	{
		/*
		 * There are at least 2 Primebook C11B versions, the older
		 * version has a product-name of "Primebook C11B", and a
		 * bios version / release / firmware revision of:
		 * V2.1.2 / 05/03/2018 / 18.2
		 * The new version has "PRIMEBOOK C11B" as product-name and a
		 * bios version / release / firmware revision of:
		 * CFALKSW05_BIOS_V1.1.2 / 11/19/2018 / 19.2
		 * Only the older version needs this quirk, note the newer
		 * version will not match as it has a different product-name.
		 */
		.ident = "Trekstor Primebook C11B",
		.matches = {
			DMI_EXACT_MATCH(DMI_SYS_VENDOR, "TREKSTOR"),
			DMI_EXACT_MATCH(DMI_PRODUCT_NAME, "Primebook C11B"),
		},
		.driver_data = (void *)&sipodev_desc
	},
	{
		.ident = "Direkt-Tek DTLAPY116-2",
		.matches = {
			DMI_EXACT_MATCH(DMI_SYS_VENDOR, "Direkt-Tek"),
			DMI_EXACT_MATCH(DMI_PRODUCT_NAME, "DTLAPY116-2"),
		},
		.driver_data = (void *)&sipodev_desc
	},
	{
		.ident = "Direkt-Tek DTLAPY133-1",
		.matches = {
			DMI_EXACT_MATCH(DMI_SYS_VENDOR, "Direkt-Tek"),
			DMI_EXACT_MATCH(DMI_PRODUCT_NAME, "DTLAPY133-1"),
		},
		.driver_data = (void *)&sipodev_desc
	},
	{
		.ident = "Mediacom Flexbook Edge 11",
		.matches = {
			DMI_EXACT_MATCH(DMI_SYS_VENDOR, "MEDIACOM"),
			DMI_EXACT_MATCH(DMI_PRODUCT_NAME, "FlexBook edge11 - M-FBE11"),
		},
		.driver_data = (void *)&sipodev_desc
	},
	{
		.ident = "Odys Winbook 13",
		.matches = {
			DMI_EXACT_MATCH(DMI_SYS_VENDOR, "AXDIA International GmbH"),
			DMI_EXACT_MATCH(DMI_PRODUCT_NAME, "WINBOOK 13"),
		},
		.driver_data = (void *)&sipodev_desc
	},
	{
		.ident = "iBall Aer3",
		.matches = {
			DMI_EXACT_MATCH(DMI_SYS_VENDOR, "iBall"),
			DMI_EXACT_MATCH(DMI_PRODUCT_NAME, "Aer3"),
		},
		.driver_data = (void *)&sipodev_desc
	},
	{ }	/* Terminate list */
};


struct i2c_hid_desc *i2c_hid_get_dmi_i2c_hid_desc_override(uint8_t *i2c_name)
{
	struct i2c_hid_desc_override *override;
	const struct dmi_system_id *system_id;

	system_id = dmi_first_match(i2c_hid_dmi_desc_override_table);
	if (!system_id)
		return NULL;

	override = system_id->driver_data;
	if (strcmp(override->i2c_name, i2c_name))
		return NULL;

	return override->i2c_hid_desc;
}

char *i2c_hid_get_dmi_hid_report_desc_override(uint8_t *i2c_name,
					       unsigned int *size)
{
	struct i2c_hid_desc_override *override;
	const struct dmi_system_id *system_id;

	system_id = dmi_first_match(i2c_hid_dmi_desc_override_table);
	if (!system_id)
		return NULL;

	override = system_id->driver_data;
	if (strcmp(override->i2c_name, i2c_name))
		return NULL;

	*size = override->hid_report_desc_size;
	return override->hid_report_desc;
}