/* dw_i2c.h - header for Design Ware I2C operations */

/*
 * Copyright (c) 2015 Intel Corporation
 *
 * SPDX-License-Identifier: Apache-2.0
 */
#ifndef ZEPHYR_DRIVERS_I2C_I2C_DW_H_
#define ZEPHYR_DRIVERS_I2C_I2C_DW_H_

#include <zephyr/drivers/i2c.h>
#include <stdbool.h>

#define DT_DRV_COMPAT snps_designware_i2c

#if DT_ANY_INST_ON_BUS_STATUS_OKAY(pcie)
BUILD_ASSERT(IS_ENABLED(CONFIG_PCIE), "DW I2C in DT needs CONFIG_PCIE");
#include <zephyr/drivers/pcie/pcie.h>
#endif

#if defined(CONFIG_RESET)
#include <zephyr/drivers/reset.h>
#endif

#ifdef __cplusplus
extern "C" {
#endif

#define I2C_DW_MAGIC_KEY			0x44570140


typedef void (*i2c_isr_cb_t)(const struct device *port);


#define IC_ACTIVITY                     (1 << 0)
#define IC_ENABLE_BIT                   (1 << 0)


/* dev->state values from IC_DATA_CMD Data transfer mode settings (bit 8) */
#define I2C_DW_STATE_READY                 (0)
#define I2C_DW_CMD_SEND                    (1 << 0)
#define I2C_DW_CMD_RECV                    (1 << 1)
#define I2C_DW_CMD_ERROR                   (1 << 2)
#define I2C_DW_BUSY                        (1 << 3)


#define DW_ENABLE_TX_INT_I2C_MASTER		(DW_INTR_STAT_TX_OVER |  \
						 DW_INTR_STAT_TX_EMPTY | \
						 DW_INTR_STAT_TX_ABRT |  \
						 DW_INTR_STAT_STOP_DET)
#define DW_ENABLE_RX_INT_I2C_MASTER		(DW_INTR_STAT_RX_UNDER | \
						 DW_INTR_STAT_RX_OVER |  \
						 DW_INTR_STAT_RX_FULL | \
						 DW_INTR_STAT_STOP_DET)

#define DW_ENABLE_TX_INT_I2C_SLAVE		(DW_INTR_STAT_RD_REQ | \
						 DW_INTR_STAT_TX_ABRT | \
						 DW_INTR_STAT_STOP_DET)
#define DW_ENABLE_RX_INT_I2C_SLAVE		(DW_INTR_STAT_RX_FULL | \
						 DW_INTR_STAT_STOP_DET)

#define DW_DISABLE_ALL_I2C_INT		0x00000000


/* IC_CON Low count and high count default values */
/* TODO verify values for high and fast speed */
#define I2C_STD_HCNT			(CONFIG_I2C_DW_CLOCK_SPEED * 4)
#define I2C_STD_LCNT			(CONFIG_I2C_DW_CLOCK_SPEED * 5)
#define I2C_FS_HCNT			((CONFIG_I2C_DW_CLOCK_SPEED * 6) / 8)
#define I2C_FS_LCNT			((CONFIG_I2C_DW_CLOCK_SPEED * 7) / 8)
#define I2C_HS_HCNT			((CONFIG_I2C_DW_CLOCK_SPEED * 6) / 8)
#define I2C_HS_LCNT			((CONFIG_I2C_DW_CLOCK_SPEED * 7) / 8)

/*
 * DesignWare speed values don't directly translate from the Zephyr speed
 * selections in include/i2c.h so here we do a little translation
 */
#define I2C_DW_SPEED_STANDARD		0x1
#define I2C_DW_SPEED_FAST		0x2
#define I2C_DW_SPEED_FAST_PLUS		0x2
#define I2C_DW_SPEED_HIGH		0x3


/*
 * These values have been randomly selected.  It would be good to test different
 * watermark levels for performance capabilities
 */
#define I2C_DW_TX_WATERMARK		2
#define I2C_DW_RX_WATERMARK		7


struct i2c_dw_rom_config {
	DEVICE_MMIO_ROM;
	i2c_isr_cb_t	config_func;
	uint32_t		bitrate;

#if defined(CONFIG_PINCTRL)
	const struct pinctrl_dev_config *pcfg;
#endif
#if defined(CONFIG_RESET)
	const struct reset_dt_spec reset;
#endif

#if DT_ANY_INST_ON_BUS_STATUS_OKAY(pcie)
	struct pcie_dev *pcie;
#endif /* I2C_DW_PCIE_ENABLED */
};

struct i2c_dw_dev_config {
	DEVICE_MMIO_RAM;
	struct k_sem		device_sync_sem;
	struct k_mutex		bus_mutex;
	uint32_t app_config;

	uint8_t			*xfr_buf;
	uint32_t		xfr_len;
	uint32_t		rx_pending;

	uint16_t		hcnt;
	uint16_t		lcnt;

	volatile uint8_t	state;  /* last direction of transfer */
	uint8_t			request_bytes;
	uint8_t			xfr_flags;
	bool			support_hs_mode;

	struct i2c_target_config *slave_cfg;
};

#define Z_REG_READ(__sz) sys_read##__sz
#define Z_REG_WRITE(__sz) sys_write##__sz
#define Z_REG_SET_BIT sys_set_bit
#define Z_REG_CLEAR_BIT sys_clear_bit
#define Z_REG_TEST_BIT sys_test_bit

#define DEFINE_MM_REG_READ(__reg, __off, __sz)				\
	static inline uint32_t read_##__reg(uint32_t addr)			\
	{								\
		return Z_REG_READ(__sz)(addr + __off);			\
	}
#define DEFINE_MM_REG_WRITE(__reg, __off, __sz)				\
	static inline void write_##__reg(uint32_t data, uint32_t addr)	\
	{								\
		Z_REG_WRITE(__sz)(data, addr + __off);			\
	}

#define DEFINE_SET_BIT_OP(__reg_bit, __reg_off, __bit)			\
	static inline void set_bit_##__reg_bit(uint32_t addr)		\
	{								\
		Z_REG_SET_BIT(addr + __reg_off, __bit);			\
	}

#define DEFINE_CLEAR_BIT_OP(__reg_bit, __reg_off, __bit)		\
	static inline void clear_bit_##__reg_bit(uint32_t addr)		\
	{								\
		Z_REG_CLEAR_BIT(addr + __reg_off, __bit);		\
	}

#define DEFINE_TEST_BIT_OP(__reg_bit, __reg_off, __bit)			\
	static inline int test_bit_##__reg_bit(uint32_t addr)		\
	{								\
		return Z_REG_TEST_BIT(addr + __reg_off, __bit);		\
	}

#ifdef __cplusplus
}
#endif

#endif /* ZEPHYR_DRIVERS_I2C_I2C_DW_H_ */