#include "util.h"
#include "i2c_driver.h"

#define AW21018_REG_GCR                 0x20
#define AW21018_REG_BRIGHTNESS_BASE     0x21
#define AW21018_REG_UPDATE              0x45
#define AW21018_REG_SL_BASE             0x46
#define AW21018_REG_GCCR                0x58
#define AW21018_REG_GCR2                0x61
#define AW21018_REG_DEVICE_RESET        0x70

#define AW21018_CHIPID                  0x02

#define AW21018_REG_GCR_CHIPEN_BIT      (1 << 0)
#define AW21018_REG_GCR_AUTO_POWER_BIT  (1 << 7)

#define AW21018_REG_GCR2_RGBMD_BIT      (1 << 0)
#define AW21018_REG_GCR2_SBMD_BIT       (1 << 1)

/* Global Current is read from the DTS entry by the kernel driver.
 * Here in the bootloader we will just hardcode it. */
#define AW21018_GLOBAL_CURRENT          0x66

#define AW21018_MAX_LED_CHANNELS        18
#define AW21018_MAX_LED_GROUPS          6

extern int lgpl_printf(const char *format, ...);
extern int i2c_master_write_and_read(int id, int target_addr, unsigned char* send_buff, int send_len, unsigned char* recv_buff, int recv_len);

int diag_i2c_led_aw210xx_detect_driver(int master_id, unsigned char slave_addr) {
	unsigned char tx_buf = AW21018_REG_DEVICE_RESET;
	unsigned char rx_buf = 0xFF;
	int ret;
	lgpl_printf("%s: master_id: %d slave_addr: 0x%x\n", __func__, master_id, slave_addr);

	ret = i2c_master_write_and_read(master_id, slave_addr, &tx_buf, 1, &rx_buf, 1);
	if (ret != 0) {
		lgpl_printf("%s: failed to read reset register.\n", __func__);
		return ret;
	}

	if (AW21018_CHIPID != rx_buf) {
		lgpl_printf("%s: chip ID did not match expected value: %d (expected: %d).\n", __func__,
			rx_buf, AW21018_CHIPID);
		return -1;
	}

	return 0;
}

static void aw210xx_write_register(int master_id, unsigned char slave_addr,
		unsigned char reg, unsigned char val)
{
	unsigned char tx_buf[2];
	int ret;

	tx_buf[0] = reg;
	tx_buf[1] = val;

	ret = i2c_master_write_and_read(master_id, slave_addr, tx_buf, 2, 0, 0);
	if (ret != 0) {
		lgpl_printf("%s: failed to set register 0x%x: error = 0x%x.\n", __func__, reg, ret);
	}
}

static void aw210xx_set_update_register(int master_id, unsigned char slave_addr) {
	aw210xx_write_register(master_id, slave_addr, AW21018_REG_UPDATE, 0x00);
}

static void aw210xx_set_brightness_registers(int master_id,
		unsigned char slave_addr, unsigned char *reg_data, size_t size)
{
	unsigned char tx_buf[AW21018_MAX_LED_GROUPS + 1];
	int len = 1;
	size_t i;
	int ret;

	/* The bootloader only operates the driver in Single Byte Configuration mode.
	 * Only allow setting the first 6 BR registers */
	tx_buf[0] = AW21018_REG_BRIGHTNESS_BASE;

	for (i = 1; i < AW21018_MAX_LED_GROUPS + 1; i++) {
		if (i <= size) {
			tx_buf[i] = reg_data[i - 1];
			len++;
		} else {
			tx_buf[i] = 0;
		}
	}

	ret = i2c_master_write_and_read(master_id, slave_addr, tx_buf, len, 0, 0);
	if (ret != 0) {
		lgpl_printf("%s: failed to set brightness registers: error = 0x%x.\n", __func__, ret);
	}

	aw210xx_set_update_register(master_id, slave_addr);
}

static void aw210xx_set_sl_registers(int master_id,
		unsigned char slave_addr, unsigned char *reg_data, size_t size)
{
	unsigned char tx_buf[AW21018_MAX_LED_CHANNELS + 1];
	int len = 1;
	size_t i;
	int ret;

	tx_buf[0] = AW21018_REG_SL_BASE;

	for (i = 1; i < AW21018_MAX_LED_CHANNELS + 1; i++) {
		if (i <= size) {
			tx_buf[i] = reg_data[i - 1];
			len++;
		} else {
			tx_buf[i] = 0;
		}
	}

	ret = i2c_master_write_and_read(master_id, slave_addr, tx_buf, len, 0, 0);
	if (ret != 0) {
		lgpl_printf("%s: failed to set SL registers: error = 0x%x.\n", __func__, ret);
	}

	aw210xx_set_update_register(master_id, slave_addr);
}

int diag_i2c_led_aw210xx_init(int master_id, unsigned char slave_addr) {
	lgpl_printf("%s: master_id: %d slave_addr: 0x%x\n", __func__, master_id, slave_addr);

	// Set CHIPEN to put AS21018 into active mode
	aw210xx_write_register(master_id, slave_addr, AW21018_REG_GCR, AW21018_REG_GCR_CHIPEN_BIT);

	// Set RGB Mode and Single Byte Configuration mode
	aw210xx_write_register(master_id, slave_addr, AW21018_REG_GCR2,
			(AW21018_REG_GCR2_RGBMD_BIT | AW21018_REG_GCR2_SBMD_BIT));

	// Set the global current control register to predefined value
	aw210xx_write_register(master_id, slave_addr, AW21018_REG_GCCR, AW21018_GLOBAL_CURRENT);

	// Set Auto power saving mode
	aw210xx_write_register(master_id, slave_addr, AW21018_REG_GCR,
			(AW21018_REG_GCR_AUTO_POWER_BIT | AW21018_REG_GCR_CHIPEN_BIT));

	return 0;
}

int diag_i2c_led_aw210xx_set_frame(int master_id, unsigned char slave_addr,
                           unsigned char *frame, size_t size)
{
	unsigned char br_buf[AW21018_MAX_LED_GROUPS] = {0};
	unsigned char sl_buf[AW21018_MAX_LED_CHANNELS] = {0};
	size_t br_index = 0;
	size_t sl_index = 0;
	size_t i = 0;

	lgpl_printf("%s: master_id: %d slave_addr: 0x%x frame: 0x%x size: %d\n", __func__,
		master_id, slave_addr, frame, size);

	// The frame should contain at least 8 bytes for brightness
	if (size < 8) {
		return -1;
	}

	/* First 8 bytes of the frame represent the brightness of 8 LEDs
	 * AW21018 only supports 6 LED BR registers in RGBMD so we only copy
	 * the first 6 values from the frame */
	for (i = 0; i < AW21018_MAX_LED_GROUPS; i++) {
		br_buf[br_index++] = frame[i];
	}

	/* Remaining 24 bytes of the frame represent RGB values.
	 * AW21018 only supports 18 channels so we only copy the first 18
	 * bytes of data */
	for (i = 8; ((i < size) && (sl_index < AW21018_MAX_LED_CHANNELS)); i+=3) {
		sl_buf[sl_index++] = frame[i];
		sl_buf[sl_index++] = frame[i + 1];
		sl_buf[sl_index++] = frame[i + 2];
	}

	aw210xx_set_brightness_registers(master_id, slave_addr, br_buf, br_index);
	aw210xx_set_sl_registers(master_id, slave_addr, sl_buf, sl_index);

	return 0;
}