path: root/drivers/input/touchscreen/ili210x.c

// SPDX-License-Identifier: GPL-2.0-only
#include <linux/crc-ccitt.h>
#include <linux/delay.h>
#include <linux/gpio/consumer.h>
#include <linux/i2c.h>
#include <linux/ihex.h>
#include <linux/input.h>
#include <linux/input/mt.h>
#include <linux/input/touchscreen.h>
#include <linux/interrupt.h>
#include <linux/mod_devicetable.h>
#include <linux/module.h>
#include <linux/sizes.h>
#include <linux/slab.h>
#include <asm/unaligned.h>

#define ILI2XXX_POLL_PERIOD	15

#define ILI210X_DATA_SIZE	64
#define ILI211X_DATA_SIZE	43
#define ILI251X_DATA_SIZE1	31
#define ILI251X_DATA_SIZE2	20

/* Touchscreen commands */
#define REG_TOUCHDATA		0x10
#define REG_PANEL_INFO		0x20
#define REG_FIRMWARE_VERSION	0x40
#define REG_PROTOCOL_VERSION	0x42
#define REG_KERNEL_VERSION	0x61
#define REG_IC_BUSY		0x80
#define REG_IC_BUSY_NOT_BUSY	0x50
#define REG_GET_MODE		0xc0
#define REG_GET_MODE_AP		0x5a
#define REG_GET_MODE_BL		0x55
#define REG_SET_MODE_AP		0xc1
#define REG_SET_MODE_BL		0xc2
#define REG_WRITE_DATA		0xc3
#define REG_WRITE_ENABLE	0xc4
#define REG_READ_DATA_CRC	0xc7
#define REG_CALIBRATE		0xcc

#define ILI251X_FW_FILENAME	"ilitek/ili251x.bin"

struct ili2xxx_chip {
	int (*read_reg)(struct i2c_client *client, u8 reg,
			void *buf, size_t len);
	int (*get_touch_data)(struct i2c_client *client, u8 *data);
	bool (*parse_touch_data)(const u8 *data, unsigned int finger,
				 unsigned int *x, unsigned int *y,
				 unsigned int *z);
	bool (*continue_polling)(const u8 *data, bool touch);
	unsigned int max_touches;
	unsigned int resolution;
	bool has_calibrate_reg;
	bool has_firmware_proto;
	bool has_pressure_reg;
};

struct ili210x {
	struct i2c_client *client;
	struct input_dev *input;
	struct gpio_desc *reset_gpio;
	struct touchscreen_properties prop;
	const struct ili2xxx_chip *chip;
	u8 version_firmware[8];
	u8 version_kernel[5];
	u8 version_proto[2];
	u8 ic_mode[2];
	bool stop;
};

static int ili210x_read_reg(struct i2c_client *client,
			    u8 reg, void *buf, size_t len)
{
	struct i2c_msg msg[] = {
		{
			.addr	= client->addr,
			.flags	= 0,
			.len	= 1,
			.buf	= &reg,
		},
		{
			.addr	= client->addr,
			.flags	= I2C_M_RD,
			.len	= len,
			.buf	= buf,
		}
	};
	int error, ret;

	ret = i2c_transfer(client->adapter, msg, ARRAY_SIZE(msg));
	if (ret != ARRAY_SIZE(msg)) {
		error = ret < 0 ? ret : -EIO;
		dev_err(&client->dev, "%s failed: %d\n", __func__, error);
		return error;
	}

	return 0;
}

static int ili210x_read_touch_data(struct i2c_client *client, u8 *data)
{
	return ili210x_read_reg(client, REG_TOUCHDATA,
				data, ILI210X_DATA_SIZE);
}

static bool ili210x_touchdata_to_coords(const u8 *touchdata,
					unsigned int finger,
					unsigned int *x, unsigned int *y,
					unsigned int *z)
{
	if (!(touchdata[0] & BIT(finger)))
		return false;

	*x = get_unaligned_be16(touchdata + 1 + (finger * 4) + 0);
	*y = get_unaligned_be16(touchdata + 1 + (finger * 4) + 2);

	return true;
}

static bool ili210x_check_continue_polling(const u8 *data, bool touch)
{
	return data[0] & 0xf3;
}

static const struct ili2xxx_chip ili210x_chip = {
	.read_reg		= ili210x_read_reg,
	.get_touch_data		= ili210x_read_touch_data,
	.parse_touch_data	= ili210x_touchdata_to_coords,
	.continue_polling	= ili210x_check_continue_polling,
	.max_touches		= 2,
	.has_calibrate_reg	= true,
};

static int ili211x_read_touch_data(struct i2c_client *client, u8 *data)
{
	s16 sum = 0;
	int error;
	int ret;
	int i;

	ret = i2c_master_recv(client, data, ILI211X_DATA_SIZE);
	if (ret != ILI211X_DATA_SIZE) {
		error = ret < 0 ? ret : -EIO;
		dev_err(&client->dev, "%s failed: %d\n", __func__, error);
		return error;
	}

	/* This chip uses custom checksum at the end of data */
	for (i = 0; i < ILI211X_DATA_SIZE - 1; i++)
		sum = (sum + data[i]) & 0xff;

	if ((-sum & 0xff) != data[ILI211X_DATA_SIZE - 1]) {
		dev_err(&client->dev,
			"CRC error (crc=0x%02x expected=0x%02x)\n",
			sum, data[ILI211X_DATA_SIZE - 1]);
		return -EIO;
	}

	return 0;
}

static bool ili211x_touchdata_to_coords(const u8 *touchdata,
					unsigned int finger,
					unsigned int *x, unsigned int *y,
					unsigned int *z)
{<