TCAN4550: TCAN4550

// SPDX-License-Identifier: GPL-2.0
// SPI to CAN driver for the Texas Instruments TCAN4x5x
// Copyright (C) 2018-19 Texas Instruments Incorporated - http://www.ti.com/

#include <linux/regmap.h>
#include <linux/spi/spi.h>

#include <linux/regulator/consumer.h>
#include <linux/gpio/consumer.h>

#include "m_can.h"

#define DEVICE_NAME "tcan4x5x"
#define TCAN4X5X_EXT_CLK_DEF 40000000

#define TCAN4X5X_DEV_ID0 0x00
#define TCAN4X5X_DEV_ID1 0x04
#define TCAN4X5X_REV 0x08
#define TCAN4X5X_STATUS 0x0C
#define TCAN4X5X_ERROR_STATUS 0x10
#define TCAN4X5X_CONTROL 0x14

#define TCAN4X5X_CONFIG 0x800
#define TCAN4X5X_TS_PRESCALE 0x804
#define TCAN4X5X_TEST_REG 0x808
#define TCAN4X5X_INT_FLAGS 0x820
#define TCAN4X5X_MCAN_INT_REG 0x824
#define TCAN4X5X_INT_EN 0x830

/* Interrupt bits */
#define TCAN4X5X_CANBUSTERMOPEN_INT_EN BIT(30)
#define TCAN4X5X_CANHCANL_INT_EN BIT(29)
#define TCAN4X5X_CANHBAT_INT_EN BIT(28)
#define TCAN4X5X_CANLGND_INT_EN BIT(27)
#define TCAN4X5X_CANBUSOPEN_INT_EN BIT(26)
#define TCAN4X5X_CANBUSGND_INT_EN BIT(25)
#define TCAN4X5X_CANBUSBAT_INT_EN BIT(24)
#define TCAN4X5X_UVSUP_INT_EN BIT(22)
#define TCAN4X5X_UVIO_INT_EN BIT(21)
#define TCAN4X5X_TSD_INT_EN BIT(19)
#define TCAN4X5X_ECCERR_INT_EN BIT(16)
#define TCAN4X5X_CANINT_INT_EN BIT(15)
#define TCAN4X5X_LWU_INT_EN BIT(14)
#define TCAN4X5X_CANSLNT_INT_EN BIT(10)
#define TCAN4X5X_CANDOM_INT_EN BIT(8)
#define TCAN4X5X_CANBUS_ERR_INT_EN BIT(5)
#define TCAN4X5X_BUS_FAULT BIT(4)
#define TCAN4X5X_MCAN_INT BIT(1)
#define TCAN4X5X_ENABLE_TCAN_INT \
	(TCAN4X5X_MCAN_INT | TCAN4X5X_BUS_FAULT | \
	 TCAN4X5X_CANBUS_ERR_INT_EN | TCAN4X5X_CANINT_INT_EN)

/* MCAN Interrupt bits */
#define TCAN4X5X_MCAN_IR_ARA BIT(29)
#define TCAN4X5X_MCAN_IR_PED BIT(28)
#define TCAN4X5X_MCAN_IR_PEA BIT(27)
#define TCAN4X5X_MCAN_IR_WD BIT(26)
#define TCAN4X5X_MCAN_IR_BO BIT(25)
#define TCAN4X5X_MCAN_IR_EW BIT(24)
#define TCAN4X5X_MCAN_IR_EP BIT(23)
#define TCAN4X5X_MCAN_IR_ELO BIT(22)
#define TCAN4X5X_MCAN_IR_BEU BIT(21)
#define TCAN4X5X_MCAN_IR_BEC BIT(20)
#define TCAN4X5X_MCAN_IR_DRX BIT(19)
#define TCAN4X5X_MCAN_IR_TOO BIT(18)
#define TCAN4X5X_MCAN_IR_MRAF BIT(17)
#define TCAN4X5X_MCAN_IR_TSW BIT(16)
#define TCAN4X5X_MCAN_IR_TEFL BIT(15)
#define TCAN4X5X_MCAN_IR_TEFF BIT(14)
#define TCAN4X5X_MCAN_IR_TEFW BIT(13)
#define TCAN4X5X_MCAN_IR_TEFN BIT(12)
#define TCAN4X5X_MCAN_IR_TFE BIT(11)
#define TCAN4X5X_MCAN_IR_TCF BIT(10)
#define TCAN4X5X_MCAN_IR_TC BIT(9)
#define TCAN4X5X_MCAN_IR_HPM BIT(8)
#define TCAN4X5X_MCAN_IR_RF1L BIT(7)
#define TCAN4X5X_MCAN_IR_RF1F BIT(6)
#define TCAN4X5X_MCAN_IR_RF1W BIT(5)
#define TCAN4X5X_MCAN_IR_RF1N BIT(4)
#define TCAN4X5X_MCAN_IR_RF0L BIT(3)
#define TCAN4X5X_MCAN_IR_RF0F BIT(2)
#define TCAN4X5X_MCAN_IR_RF0W BIT(1)
#define TCAN4X5X_MCAN_IR_RF0N BIT(0)
#define TCAN4X5X_RESET_GPIO 75



//#ifdef CONFIG_MX6ULL_IWG26I
#define TCAN4X5X_ENABLE_MCAN_INT \
	(TCAN4X5X_MCAN_IR_TC | TCAN4X5X_MCAN_IR_RF0F | \
		 TCAN4X5X_MCAN_IR_RF1F | TCAN4X5X_MCAN_IR_RF0W | \
	 TCAN4X5X_MCAN_IR_RF1W)
//#else
 /* CONFIG_MX6ULL_IWG26I */
//#define TCAN4X5X_ENABLE_MCAN_INT \
//	(TCAN4X5X_MCAN_IR_TC | TCAN4X5X_MCAN_IR_RF0N | \
//	 TCAN4X5X_MCAN_IR_RF1N | TCAN4X5X_MCAN_IR_RF0F | \
//	 TCAN4X5X_MCAN_IR_RF1F)
//#endif 
/* CONFIG_MX6ULL_IWG26I */

#define CTRL_REG	0x1018
#define CTRL_INIT_BIT	BIT(0)
#define CTRL_CCE_BIT	BIT(1)
#define RX_FIFO0_CONFIGURATION_REG	0x10A0
#define RX_FIFO0_WATERMARK_BIT	BIT(24)




#define TCAN4X5X_MRAM_START 0x8000
#define TCAN4X5X_MCAN_OFFSET 0x1000
#define TCAN4X5X_MAX_REGISTER 0x8fff

#define TCAN4X5X_CLEAR_ALL_INT 0xffffffff
#define TCAN4X5X_SET_ALL_INT 0xffffffff

#define TCAN4X5X_WRITE_CMD (0x61 << 24)
#define TCAN4X5X_READ_CMD (0x41 << 24)

#define TCAN4X5X_MODE_SEL_MASK (BIT(7) | BIT(6))
#define WDT_ENABLE (BIT(3) | BIT(4))
#define WDT_ENABLE_BIT BIT(3)
#define WDT_CLK (BIT(27) | BIT(28))
#define WDT_CLK_BIT BIT(27)
#define WDT_RESET (BIT(18) | BIT(19))
#define WDT_RESET_BIT BIT(18)
#define WDT_TIM (BIT(28) | BIT(29))
#define WDT_TIM_BIT BIT(29)
#define TCAN4X5X_MODE_SLEEP 0x00
#define TCAN4X5X_MODE_STANDBY BIT(6)
#define TCAN4X5X_MODE_NORMAL BIT(7)

#define TCAN4X5X_SW_RESET BIT(2)

#define TCAN4X5X_MCAN_CONFIGURED BIT(5)
#define TCAN4X5X_WATCHDOG_EN BIT(3)
#define TCAN4X5X_WD_60_MS_TIMER 0
#define TCAN4X5X_WD_600_MS_TIMER BIT(28)
#define TCAN4X5X_WD_3_S_TIMER BIT(29)
#define TCAN4X5X_WD_6_S_TIMER (BIT(28) | BIT(29))

bool iw_tcan_prop = false; /* Flag added for Rugged Telematics Device */
int iw_rxf0_reg_val; /* Variable to store the RX FIFO 0 Configuration register */
struct tcan4x5x_priv {
	struct regmap *regmap;
	struct spi_device *spi;

	struct m_can_classdev *mcan_dev;

	struct gpio_desc *reset_gpio;
	struct gpio_desc *device_wake_gpio;
	struct gpio_desc *device_state_gpio;
	struct regulator *power;

	/* Register based ip */
	int mram_start;
	int reg_offset;
};

static struct can_bittiming_const tcan4x5x_bittiming_const = {
	.name = DEVICE_NAME,
	.tseg1_min = 2,
	.tseg1_max = 31,
	.tseg2_min = 2,
	.tseg2_max = 16,
	.sjw_max = 16,
	.brp_min = 1,
	.brp_max = 32,
	.brp_inc = 1,
};

static struct can_bittiming_const tcan4x5x_data_bittiming_const = {
	.name = DEVICE_NAME,
	.tseg1_min = 1,
	.tseg1_max = 32,
	.tseg2_min = 1,
	.tseg2_max = 16,
	.sjw_max = 16,
	.brp_min = 1,
	.brp_max = 32,
	.brp_inc = 1,
};

static void tcan4x5x_check_wake(struct tcan4x5x_priv *priv)
{
	int wake_state = 0;

	if (priv->device_state_gpio)
		wake_state = gpiod_get_value(priv->device_state_gpio);

	if (priv->device_wake_gpio && wake_state) {
		gpiod_set_value(priv->device_wake_gpio, 0);
		usleep_range(5, 50);
		gpiod_set_value(priv->device_wake_gpio, 1);
	}
}

static int tcan4x5x_reset(struct tcan4x5x_priv *priv)
{
	int ret = 0;

	if (priv->reset_gpio) {
		gpiod_set_value(priv->reset_gpio, 1);

		/* tpulse_width minimum 30us */
		usleep_range(30, 100);
		gpiod_set_value(priv->reset_gpio, 0);
	} else {
		ret = regmap_write(priv->regmap, TCAN4X5X_CONFIG,
				TCAN4X5X_SW_RESET);
		if (ret)
			return ret;
	}

	usleep_range(700, 1000);

	return ret;
}

static int regmap_spi_gather_write(void *context, const void *reg,
		size_t reg_len, const void *val,
		size_t val_len)
{
	struct device *dev = context;
	struct spi_device *spi = to_spi_device(dev);
	struct spi_message m;
	u32 addr;
	struct spi_transfer t[2] = {
		{ .tx_buf = &addr, .len = reg_len, .cs_change = 0,},
		{ .tx_buf = val, .len = val_len, },
	};

	addr = TCAN4X5X_WRITE_CMD | (*((u16 *)reg) << 8) | val_len >> 2;

	spi_message_init(&m);
	spi_message_add_tail(&t[0], &m);
	spi_message_add_tail(&t[1], &m);

	return spi_sync(spi, &m);
}

static int tcan4x5x_regmap_write(void *context, const void *data, size_t count)
{
	u16 *reg = (u16 *)(data);
	const u32 *val = data + 4;

	return regmap_spi_gather_write(context, reg, 4, val, count - 4);
}

static int regmap_spi_async_write(void *context,
		const void *reg, size_t reg_len,
		const void *val, size_t val_len,
		struct regmap_async *a)
{
	return -ENOTSUPP;
}

static struct regmap_async *regmap_spi_async_alloc(void)
{
	return NULL;
}

static int tcan4x5x_regmap_read(void *context,
		const void *reg, size_t reg_size,
		void *val, size_t val_size)
{
	struct device *dev = context;
	struct spi_device *spi = to_spi_device(dev);

	u32 addr = TCAN4X5X_READ_CMD | (*((u16 *)reg) << 8) | val_size >> 2;

	return spi_write_then_read(spi, &addr, reg_size, (u32 *)val, val_size);
}

static struct regmap_bus tcan4x5x_bus = {
	.write = tcan4x5x_regmap_write,
	.gather_write = regmap_spi_gather_write,
	.async_write = regmap_spi_async_write,
	.async_alloc = regmap_spi_async_alloc,
	.read = tcan4x5x_regmap_read,
	.read_flag_mask = 0x00,
	.reg_format_endian_default = REGMAP_ENDIAN_NATIVE,
	.val_format_endian_default = REGMAP_ENDIAN_NATIVE,
};

static u32 tcan4x5x_read_reg(struct m_can_classdev *cdev, int reg)
{
	struct tcan4x5x_priv *priv = cdev->device_data;
	u32 val;

	regmap_read(priv->regmap, priv->reg_offset + reg, &val);

	return val;
}

static u32 tcan4x5x_read_fifo(struct m_can_classdev *cdev, int addr_offset)
{
	struct tcan4x5x_priv *priv = cdev->device_data;
	u32 val;

	regmap_read(priv->regmap, priv->mram_start + addr_offset, &val);

	return val;
}

static int tcan4x5x_write_reg(struct m_can_classdev *cdev, int reg, int val)
{
	struct tcan4x5x_priv *priv = cdev->device_data;

	return regmap_write(priv->regmap, priv->reg_offset + reg, val);
}

static int tcan4x5x_write_fifo(struct m_can_classdev *cdev,
		int addr_offset, int val)
{
	struct tcan4x5x_priv *priv = cdev->device_data;

	return regmap_write(priv->regmap, priv->mram_start + addr_offset, val);
}

static int tcan4x5x_power_enable(struct regulator *reg, int enable)
{
	if (IS_ERR_OR_NULL(reg))
		return 0;

	if (enable)
		return regulator_enable(reg);
	else
		return regulator_disable(reg);
}

static int tcan4x5x_write_tcan_reg(struct m_can_classdev *cdev,
		int reg, int val)
{
	struct tcan4x5x_priv *priv = cdev->device_data;

	return regmap_write(priv->regmap, reg, val);
}

static int tcan4x5x_clear_interrupts(struct m_can_classdev *cdev)
{
	int ret;
	struct tcan4x5x_priv *tcan4x5x = cdev->device_data;
	ret = tcan4x5x_write_tcan_reg(cdev, TCAN4X5X_STATUS,
			TCAN4X5X_CLEAR_ALL_INT);
	if (ret)
		return ret;

	ret = tcan4x5x_write_tcan_reg(cdev, TCAN4X5X_MCAN_INT_REG,
			TCAN4X5X_ENABLE_MCAN_INT);
	if (ret)
		return ret;

	ret = tcan4x5x_write_tcan_reg(cdev, TCAN4X5X_INT_FLAGS,
			TCAN4X5X_CLEAR_ALL_INT);
	if (ret)
		return ret;

	ret = tcan4x5x_write_tcan_reg(cdev, TCAN4X5X_ERROR_STATUS,
			TCAN4X5X_CLEAR_ALL_INT);
	if (ret)
		return ret;
	/* Watchdog reset */
	ret = regmap_update_bits(tcan4x5x->regmap, TCAN4X5X_CONFIG,
			WDT_RESET, WDT_RESET_BIT);
	if (ret)
		return ret;

	return ret;
}

static int tcan4x5x_init(struct m_can_classdev *cdev)
{
	struct tcan4x5x_priv *tcan4x5x = cdev->device_data;
	int ret;

	tcan4x5x_check_wake(tcan4x5x);
	printk("tcan init----\n");

	ret = tcan4x5x_write_tcan_reg(cdev, TCAN4X5X_INT_EN,
			TCAN4X5X_ENABLE_TCAN_INT);
	if (ret)
		return ret;
	ret = regmap_update_bits(tcan4x5x->regmap, TCAN4X5X_CONFIG,
			WDT_CLK, WDT_CLK_BIT);
	if (ret)
		return ret;
	ret = regmap_update_bits(tcan4x5x->regmap, TCAN4X5X_CONFIG,
			WDT_ENABLE, WDT_ENABLE_BIT);
	if (ret)
		return ret;
	ret = tcan4x5x_clear_interrupts(cdev);
	if (ret)
		return ret;
	ret = regmap_update_bits(tcan4x5x->regmap, TCAN4X5X_CONFIG,
			TCAN4X5X_MODE_SEL_MASK, TCAN4X5X_MODE_NORMAL);
	if (ret)
		return ret;
	/* Zero out the MCAN buffers */
	m_can_init_ram(cdev);

	return ret;
}

static int tcan4x5x_parse_config(struct m_can_classdev *cdev)
{
	struct tcan4x5x_priv *tcan4x5x = cdev->device_data;
	int ret;
	printk("tcan parse config----------\n");

	if (!iw_tcan_prop)
	{
		tcan4x5x->device_wake_gpio = devm_gpiod_get(cdev->dev, "device-wake",
				GPIOD_OUT_HIGH);
		if (IS_ERR(tcan4x5x->device_wake_gpio)) {
			dev_err(cdev->dev, "device-wake gpio not defined\n");
			return -EINVAL;
		}
	}

	tcan4x5x->reset_gpio = devm_gpiod_get_optional(cdev->dev, "reset",
			GPIOD_OUT_LOW);
	if (IS_ERR(tcan4x5x->reset_gpio))
		tcan4x5x->reset_gpio = NULL;

	if (!iw_tcan_prop)
	{
		ret = tcan4x5x_reset(tcan4x5x);
		if (ret)
			return ret;
	}

	tcan4x5x->device_state_gpio = devm_gpiod_get_optional(cdev->dev,
			"device-state",
			GPIOD_IN);
	if (IS_ERR(tcan4x5x->device_state_gpio))
		tcan4x5x->device_state_gpio = NULL;

	tcan4x5x->power = devm_regulator_get_optional(cdev->dev,
			"vsup");
	if (PTR_ERR(tcan4x5x->power) == -EPROBE_DEFER)
		return -EPROBE_DEFER;

	return 0;
}

static const struct regmap_config tcan4x5x_regmap = {
	.reg_bits = 32,
	.val_bits = 32,
	.cache_type = REGCACHE_NONE,
	.max_register = TCAN4X5X_MAX_REGISTER,
};

static struct m_can_ops tcan4x5x_ops = {
	.init = tcan4x5x_init,
	.read_reg = tcan4x5x_read_reg,
	.write_reg = tcan4x5x_write_reg,
	.write_fifo = tcan4x5x_write_fifo,
	.read_fifo = tcan4x5x_read_fifo,
	.clear_interrupts = tcan4x5x_clear_interrupts,
};

/*
* Added for the reset of TCAN4X5X chip
*/
static int tcan4x5x_wakeup_mode( void )
{
	usleep_range(10, 50);
	gpio_request(TCAN4X5X_RESET_GPIO, "TCAN_ON");
	gpio_direction_output(TCAN4X5X_RESET_GPIO, 0);
	gpio_set_value(TCAN4X5X_RESET_GPIO, 0);
	usleep_range(1, 50);

	gpio_request(TCAN4X5X_RESET_GPIO, "TCAN_ON");
	gpio_direction_output(TCAN4X5X_RESET_GPIO, 0);
	gpio_set_value(TCAN4X5X_RESET_GPIO, 1);
	usleep_range(1, 50);

	gpio_request(TCAN4X5X_RESET_GPIO, "TCAN_ON");
	gpio_direction_output(TCAN4X5X_RESET_GPIO, 0);
	gpio_set_value(TCAN4X5X_RESET_GPIO, 0);
	usleep_range(1, 50);

	return 0;
}

static int tcan4x5x_can_probe(struct spi_device *spi)
{
	struct tcan4x5x_priv *priv;
	struct m_can_classdev *mcan_class;
	int freq, ret;
	printk("tcan probe---------\n");

	/* For finding the TCAN node */
	struct device_node *tcan_node;
	tcan_node = of_find_compatible_node(NULL, NULL, "ti,tcan4x5x");
	if (!tcan_node) {
		printk("%s : can't find TCAN node\n", __func__);
		return -EINVAL;
	}

	/* For finding the iWave flag defined in Device Tree */
	if (of_get_property(tcan_node, "iw-tcan-prop", NULL))
	{
		iw_tcan_prop = true;
		m_can_set_iw_mcan_prop_flag();
		tcan4x5x_wakeup_mode( );
		msleep(100);
	}

	mcan_class = m_can_class_allocate_dev(&spi->dev);
	if (!mcan_class)
		return -ENOMEM;

	priv = devm_kzalloc(&spi->dev, sizeof(*priv), GFP_KERNEL);
	if (!priv)
		return -ENOMEM;

	mcan_class->device_data = priv;

	m_can_class_get_clocks(mcan_class);
	if (IS_ERR(mcan_class->cclk)) {
		dev_err(&spi->dev, "no CAN clock source defined\n");
		freq = TCAN4X5X_EXT_CLK_DEF;
	} else {
		freq = clk_get_rate(mcan_class->cclk);
	}

	/* Sanity check */
	if (freq < 20000000 || freq > TCAN4X5X_EXT_CLK_DEF)
		return -ERANGE;

	priv->reg_offset = TCAN4X5X_MCAN_OFFSET;
	priv->mram_start = TCAN4X5X_MRAM_START;
	priv->spi = spi;
	priv->mcan_dev = mcan_class;

	mcan_class->pm_clock_support = 0;
	mcan_class->can.clock.freq = freq;
	mcan_class->dev = &spi->dev;
	mcan_class->ops = &tcan4x5x_ops;
	mcan_class->is_peripheral = true;
	mcan_class->bit_timing = &tcan4x5x_bittiming_const;
	mcan_class->data_timing = &tcan4x5x_data_bittiming_const;
	mcan_class->net->irq = spi->irq;

	spi_set_drvdata(spi, priv);

	ret = tcan4x5x_parse_config(mcan_class);
	if (ret)
		goto out_clk;

	/* Configure the SPI bus */
	spi->bits_per_word = 32;
	ret = spi_setup(spi);
	if (ret)
		goto out_clk;

	priv->regmap = devm_regmap_init(&spi->dev, &tcan4x5x_bus,
			&spi->dev, &tcan4x5x_regmap);

	tcan4x5x_power_enable(priv->power, 1);

	ret = tcan4x5x_init(mcan_class);
	if (ret)
		goto out_power;

	ret = m_can_class_register(mcan_class);
	if (ret)
		goto out_power;

	if (of_get_property(tcan_node, "wakeup-source", NULL))
        {
                device_init_wakeup(mcan_class->dev, true);
        }

	netdev_info(mcan_class->net, "TCAN4X5X successfully initialized.\n");
	return 0;

out_power:
	tcan4x5x_power_enable(priv->power, 0);
out_clk:
	if (!IS_ERR(mcan_class->cclk)) {
		clk_disable_unprepare(mcan_class->cclk);
		clk_disable_unprepare(mcan_class->hclk);
	}

	dev_err(&spi->dev, "Probe failed, err=%d\n", ret);
	return ret;
}

static int tcan4x5x_sleep_mode( struct tcan4x5x_priv *priv )
{
	struct tcan4x5x_priv *tcan4x5x =
		(struct tcan4x5x_priv *)priv;
	int ret;
	ret = regmap_update_bits(tcan4x5x->regmap, TCAN4X5X_CONFIG,
			TCAN4X5X_MODE_SEL_MASK, TCAN4X5X_MODE_SLEEP );
	return ret;
}

static int tcan4x5x_can_remove(struct spi_device *spi)
{
	struct tcan4x5x_priv *priv = spi_get_drvdata(spi);

	printk("tcan remove------\n");
	if (iw_tcan_prop)
	{
		tcan4x5x_sleep_mode( priv );
	}
	tcan4x5x_power_enable(priv->power, 0);

	m_can_class_unregister(priv->mcan_dev);

	return 0;
}

static int tcan4x5x_suspend(struct device *device)
{
        int err = 0, ret = 0;
        struct tcan4x5x_priv *priv = spi_get_drvdata(to_spi_device(device));
        struct net_device *dev = priv->mcan_dev->net;
	
	printk("tcan suspend-------\n");
        if (netif_running(dev))
        {
                if (device_may_wakeup(device))
                {
			iw_rxf0_reg_val = 0;
                        /* 
                         * For modifying the watermark level for CAN, the INIT and \
                         * CCE bits should be high. Those are Write protected bits. \
                         * */
                        err = regmap_update_bits(priv->regmap, CTRL_REG, CTRL_INIT_BIT, CTRL_INIT_BIT);
                        if (err)
                                return err;

                        err = regmap_update_bits(priv->regmap, CTRL_REG, CTRL_CCE_BIT, CTRL_CCE_BIT);
                        if (err)
                                return err;

                        /* 
                         * Reading the current value of RX FIFO 0 register and \
                         * stores it in iw_rxf0_reg_val to revert it back. \
                         * */
                        regmap_read(priv->regmap, RX_FIFO0_CONFIGURATION_REG, &iw_rxf0_reg_val);

                        /* Modify the watermark level as 1 in RX FIFO 0 CONF Register. */
                        err = iw_rxf0_reg_val & 0x80FFFFFF;
                        err |= 1 << 24;
                        ret = regmap_write(priv->regmap, RX_FIFO0_CONFIGURATION_REG, err);
                        if (ret)
                                return ret;

                        /* Disable the periodic Watchdog interrupt in RX FIFO 0 CONF Register. */
                        err = regmap_update_bits(priv->regmap, TCAN4X5X_CONFIG, TCAN4X5X_WATCHDOG_EN, !TCAN4X5X_WATCHDOG_EN);
                        if (err)
                                return err;

                        /* Disabling the INIT and CCE bits after changing the Watermark level. */
                        err = regmap_update_bits(priv->regmap, CTRL_REG, CTRL_CCE_BIT, !CTRL_CCE_BIT);
                        if (err)
                                return err;

                        err = regmap_update_bits(priv->regmap, CTRL_REG, CTRL_INIT_BIT, !CTRL_INIT_BIT);
                        if (err)
                                return err;

                        /* Enable the IRQ wakeup */
                        err = enable_irq_wake(priv->mcan_dev->net->irq);
			                  if(err)
                                return err;

                        err = m_can_class_suspend(device);
                          if(err)
                          return err;
                }
        }

        return err;
}
static int tcan4x5x_resume(struct device *device)
{
        int err = 0;
        struct tcan4x5x_priv *priv = spi_get_drvdata(to_spi_device(device));
        struct net_device *dev = priv->mcan_dev->net;
	
	printk("tcan resume---------\n");
        if (netif_running(dev))
        {
                if (device_may_wakeup(device))
                {
                        /* Disable the RX interrupts */
                        m_can_disable_rx_irq(priv->mcan_dev);

                        /* Disable the IRQ wakeup */
                        err = disable_irq_wake(priv->mcan_dev->net->irq);
                        if(err)
                                return err;

                        if (priv->mcan_dev->ops->clear_interrupts)
                        {
                                priv->mcan_dev->ops->clear_interrupts(priv->mcan_dev);
                        }
                        if (priv->mcan_dev->ops->clear_interrupts_tx)
                        {
                                priv->mcan_dev->ops->clear_interrupts_tx(priv->mcan_dev);
                        }

                        err = m_can_rx_clear(dev);
                        if(err)
                                return err;

                        /* 
                         * For modifying the watermark level for CAN, the INIT and \
                         * CCE bits should be high. Those are Write protected bits. \
                         * */
                        err = regmap_update_bits(priv->regmap, CTRL_REG, CTRL_INIT_BIT, CTRL_INIT_BIT);
                        if (err)
                                return err;

                        err = regmap_update_bits(priv->regmap, CTRL_REG, CTRL_CCE_BIT, CTRL_CCE_BIT);
                        if (err)
                                return err;

                        err = regmap_update_bits(priv->regmap, TCAN4X5X_CONFIG, WDT_RESET, WDT_RESET_BIT);
                        if (err)
                                return err;

                        err = regmap_update_bits(priv->regmap, TCAN4X5X_CONFIG, TCAN4X5X_WATCHDOG_EN, TCAN4X5X_WATCHDOG_EN);
                        if (err)
                                return err;

			         /* 
                         * Reverting back the value of RX FIFO 0 register which was \
                         * stored in iw_rxf0_reg_val. This will reverts the Watermark \
                         * value to the previous value. \
                         * */
                        err = regmap_write(priv->regmap, RX_FIFO0_CONFIGURATION_REG, iw_rxf0_reg_val);
                        if (err)
                                return err;

                        err = regmap_update_bits(priv->regmap, CTRL_REG, CTRL_CCE_BIT, !CTRL_CCE_BIT);
                        if (err)
                                return err;

                        err = regmap_update_bits(priv->regmap, CTRL_REG, CTRL_INIT_BIT, !CTRL_INIT_BIT);
                        if (err)
                                return err;

                        err = m_can_class_resume(device);
                        if(err)
                                return err;

                        /* Enable the RX interrupts */
                        m_can_enable_rx_irq(priv->mcan_dev);
                }
        }

        return err;
}

static const struct dev_pm_ops tcan4x5x_pm_ops = {
	SET_SYSTEM_SLEEP_PM_OPS(tcan4x5x_suspend, tcan4x5x_resume)
};


static const struct of_device_id tcan4x5x_of_match[] = {
	{ .compatible = "ti,tcan4x5x", },
	{ }
};
MODULE_DEVICE_TABLE(of, tcan4x5x_of_match);

static const struct spi_device_id tcan4x5x_id_table[] = {
	{
		.name		= "tcan4x5x",
		.driver_data	= 0,
	},
	{ }
};
MODULE_DEVICE_TABLE(spi, tcan4x5x_id_table);

static struct spi_driver tcan4x5x_can_driver = {
	.driver = {
		.name = DEVICE_NAME,
		.of_match_table = tcan4x5x_of_match,
		.pm = NULL,
		.pm = &tcan4x5x_pm_ops,
	},
	.id_table = tcan4x5x_id_table,
	.probe = tcan4x5x_can_probe,
	.remove = tcan4x5x_can_remove,
};
module_spi_driver(tcan4x5x_can_driver);

MODULE_AUTHOR("Dan Murphy <dmurphy@ti.com>");
MODULE_DESCRIPTION("Texas Instruments TCAN4x5x CAN driver");
MODULE_LICENSE("GPL v2");

// SPDX-License-Identifier: GPL-2.0
// CAN bus driver for Bosch M_CAN controller
// Copyright (C) 2014 Freescale Semiconductor, Inc.
//      Dong Aisheng <b29396@freescale.com>
// Copyright (C) 2018-19 Texas Instruments Incorporated - http://www.ti.com/

/* Bosch M_CAN user manual can be obtained from:
 * http://www.bosch-semiconductors.de/media/pdf_1/ipmodules_1/m_can/
 * mcan_users_manual_v302.pdf
 */

#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/netdevice.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/platform_device.h>
#include <linux/pm_runtime.h>
#include <linux/iopoll.h>
#include <linux/can/dev.h>
#include <linux/pinctrl/consumer.h>

#include "m_can.h"
bool iw_mcan_prop = false; /* Flag added for Rugged Telematics Device */
int iw_ie_reg = 0;
bool mode = false;         /* Flag added for determining when tcan has to go to standby mode */
bool FD_mode = false;
#if 0
int m_can_rx_clear(struct net_device *dev)
{
        struct m_can_classdev *cdev = netdev_priv(dev);
        m_can_disable_all_interrupts(cdev);
        m_can_rx_peripheral(dev);

        return 0;
}
EXPORT_SYMBOL_GPL(m_can_rx_clear);
#endif




/* registers definition */
enum m_can_reg {
	M_CAN_CREL	= 0x0,
	M_CAN_ENDN	= 0x4,
	M_CAN_CUST	= 0x8,
	M_CAN_DBTP	= 0xc,
	M_CAN_TEST	= 0x10,
	M_CAN_RWD	= 0x14,
	M_CAN_CCCR	= 0x18,
	M_CAN_NBTP	= 0x1c,
	M_CAN_TSCC	= 0x20,
	M_CAN_TSCV	= 0x24,
	M_CAN_TOCC	= 0x28,
	M_CAN_TOCV	= 0x2c,
	M_CAN_ECR	= 0x40,
	M_CAN_PSR	= 0x44,
	/* TDCR Register only available for version >=3.1.x */
	M_CAN_TDCR	= 0x48,
	M_CAN_IR	= 0x50,
	M_CAN_IE	= 0x54,
	M_CAN_ILS	= 0x58,
	M_CAN_ILE	= 0x5c,
	M_CAN_GFC	= 0x80,
	M_CAN_SIDFC	= 0x84,
	M_CAN_XIDFC	= 0x88,
	M_CAN_XIDAM	= 0x90,
	M_CAN_HPMS	= 0x94,
	M_CAN_NDAT1	= 0x98,
	M_CAN_NDAT2	= 0x9c,
	M_CAN_RXF0C	= 0xa0,
	M_CAN_RXF0S	= 0xa4,
	M_CAN_RXF0A	= 0xa8,
	M_CAN_RXBC	= 0xac,
	M_CAN_RXF1C	= 0xb0,
	M_CAN_RXF1S	= 0xb4,
	M_CAN_RXF1A	= 0xb8,
	M_CAN_RXESC	= 0xbc,
	M_CAN_TXBC	= 0xc0,
	M_CAN_TXFQS	= 0xc4,
	M_CAN_TXESC	= 0xc8,
	M_CAN_TXBRP	= 0xcc,
	M_CAN_TXBAR	= 0xd0,
	M_CAN_TXBCR	= 0xd4,
	M_CAN_TXBTO	= 0xd8,
	M_CAN_TXBCF	= 0xdc,
	M_CAN_TXBTIE	= 0xe0,
	M_CAN_TXBCIE	= 0xe4,
	M_CAN_TXEFC	= 0xf0,
	M_CAN_TXEFS	= 0xf4,
	M_CAN_TXEFA	= 0xf8,
};
/*Transmission delay */
volatile int Tx_DELAY = 0;
/* napi related */
#define M_CAN_NAPI_WEIGHT	64

/* message ram configuration data length */
#define MRAM_CFG_LEN	8

/* Core Release Register (CREL) */
#define CREL_REL_SHIFT		28
#define CREL_REL_MASK		(0xF << CREL_REL_SHIFT)
#define CREL_STEP_SHIFT		24
#define CREL_STEP_MASK		(0xF << CREL_STEP_SHIFT)
#define CREL_SUBSTEP_SHIFT	20
#define CREL_SUBSTEP_MASK	(0xF << CREL_SUBSTEP_SHIFT)

/* Data Bit Timing & Prescaler Register (DBTP) */
#define DBTP_TDC		BIT(23)
#define DBTP_DBRP_SHIFT		16
#define DBTP_DBRP_MASK		(0x1f << DBTP_DBRP_SHIFT)
#define DBTP_DTSEG1_SHIFT	8
#define DBTP_DTSEG1_MASK	(0x1f << DBTP_DTSEG1_SHIFT)
#define DBTP_DTSEG2_SHIFT	4
#define DBTP_DTSEG2_MASK	(0xf << DBTP_DTSEG2_SHIFT)
#define DBTP_DSJW_SHIFT		0
#define DBTP_DSJW_MASK		(0xf << DBTP_DSJW_SHIFT)

/* Transmitter Delay Compensation Register (TDCR) */
#define TDCR_TDCO_SHIFT		8
#define TDCR_TDCO_MASK		(0x7F << TDCR_TDCO_SHIFT)
#define TDCR_TDCF_SHIFT		0
#define TDCR_TDCF_MASK		(0x7F << TDCR_TDCF_SHIFT)

/* Test Register (TEST) */
#define TEST_LBCK		BIT(4)

/* CC Control Register(CCCR) */
#define CCCR_CMR_MASK		0x3
#define CCCR_CMR_SHIFT		10
#define CCCR_CMR_CANFD		0x1
#define CCCR_CMR_CANFD_BRS	0x2
#define CCCR_CMR_CAN		0x3
#define CCCR_CME_MASK		0x3
#define CCCR_CME_SHIFT		8
#define CCCR_CME_CAN		0
#define CCCR_CME_CANFD		0x1
#define CCCR_CME_CANFD_BRS	0x2
#define CCCR_TXP		BIT(14)
#define CCCR_TEST		BIT(7)
#define CCCR_MON		BIT(5)
#define CCCR_CSR		BIT(4)
#define CCCR_CSA		BIT(3)
#define CCCR_ASM		BIT(2)
#define CCCR_CCE		BIT(1)
#define CCCR_INIT		BIT(0)
#define CCCR_CANFD		0x10
/* for version >=3.1.x */
#define CCCR_EFBI		BIT(13)
#define CCCR_PXHD		BIT(12)
#define CCCR_BRSE               BIT(9)
#define CCCR_FDOE               BIT(8)
/* only for version >=3.2.x */
#define CCCR_NISO		BIT(15)

/* Nominal Bit Timing & Prescaler Register (NBTP) */
#define NBTP_NSJW_SHIFT		25
#define NBTP_NSJW_MASK		(0x7f << NBTP_NSJW_SHIFT)
#define NBTP_NBRP_SHIFT		16
#define NBTP_NBRP_MASK		(0x1ff << NBTP_NBRP_SHIFT)
#define NBTP_NTSEG1_SHIFT	8
#define NBTP_NTSEG1_MASK	(0xff << NBTP_NTSEG1_SHIFT)
#define NBTP_NTSEG2_SHIFT	0
#define NBTP_NTSEG2_MASK	(0x7f << NBTP_NTSEG2_SHIFT)

/* Error Counter Register(ECR) */
#define ECR_RP			BIT(15)
#define ECR_REC_SHIFT		8
#define ECR_REC_MASK		(0x7f << ECR_REC_SHIFT)
#define ECR_TEC_SHIFT		0
#define ECR_TEC_MASK		0xff

/* Protocol Status Register(PSR) */
#define PSR_BO		BIT(7)
#define PSR_EW		BIT(6)
#define PSR_EP		BIT(5)
#define PSR_LEC_MASK	0x7

/* Interrupt Register(IR) */
#define IR_ALL_INT	0xffffffff

/* Renamed bits for versions > 3.1.x */
#define IR_ARA		BIT(29)
#define IR_PED		BIT(28)
#define IR_PEA		BIT(27)

/* Bits for version 3.0.x */
#define IR_STE		BIT(31)
#define IR_FOE		BIT(30)
#define IR_ACKE		BIT(29)
#define IR_BE		BIT(28)
#define IR_CRCE		BIT(27)
#define IR_WDI		BIT(26)
#define IR_BO		BIT(25)
#define IR_EW		BIT(24)
#define IR_EP		BIT(23)
#define IR_ELO		BIT(22)
#define IR_BEU		BIT(21)
#define IR_BEC		BIT(20)
#define IR_DRX		BIT(19)
#define IR_TOO		BIT(18)
#define IR_MRAF		BIT(17)
#define IR_TSW		BIT(16)
#define IR_TEFL		BIT(15)
#define IR_TEFF		BIT(14)
#define IR_TEFW		BIT(13)
#define IR_TEFN		BIT(12)
#define IR_TFE		BIT(11)
#define IR_TCF		BIT(10)
#define IR_TC		BIT(9)
#define IR_HPM		BIT(8)
#define IR_RF1L		BIT(7)
#define IR_RF1F		BIT(6)
#define IR_RF1W		BIT(5)
#define IR_RF1N		BIT(4)
#define IR_RF0L		BIT(3)
#define IR_RF0F		BIT(2)
#define IR_RF0W		BIT(1)
#define IR_RF0N		BIT(0)
#define IR_ERR_STATE	(IR_BO | IR_EW | IR_EP)

/* Interrupts for version 3.0.x */
#define IR_ERR_LEC_30X	(IR_STE	| IR_FOE | IR_ACKE | IR_BE | IR_CRCE)
#define IR_ERR_BUS_30X	(IR_ERR_LEC_30X | IR_WDI | IR_ELO | IR_BEU | \
		IR_BEC | IR_TOO | IR_MRAF | IR_TSW | IR_TEFL | \
		IR_RF1L | IR_RF0L)
#define IR_ERR_ALL_30X	(IR_ERR_STATE | IR_ERR_BUS_30X)
/* Interrupts for version >= 3.1.x */
//#ifdef CONFIG_MX6ULL_IWG26I
#define IR_ERR_LEC_31X	(IR_PED | IR_PEA | IR_RF0N | IR_RF1N )
//#else
 /* CONFIG_MX6ULL_IWG26I */
//#define IR_ERR_LEC_31X	(IR_PED | IR_PEA)
//#endif
 /* CONFIG_MX6ULL_IWG26I */
#define IR_ERR_BUS_31X      (IR_ERR_LEC_31X | IR_WDI | IR_ELO | IR_BEU | \
		IR_BEC | IR_TOO | IR_MRAF | IR_TSW | IR_TEFL | \
		IR_RF1L | IR_RF0L)
#define IR_ERR_ALL_31X	(IR_ERR_STATE | IR_ERR_BUS_31X)

/* Interrupt Line Select (ILS) */
#define ILS_ALL_INT0	0x0
#define ILS_ALL_INT1	0xFFFFFFFF

/* Interrupt Line Enable (ILE) */
#define ILE_EINT1	BIT(1)
#define ILE_EINT0	BIT(0)

/* Rx FIFO 0/1 Configuration (RXF0C/RXF1C) */
#define RXFC_FWM_SHIFT	24
#define RXFC_FWM_MASK	(0x7f << RXFC_FWM_SHIFT)
#define RXFC_FS_SHIFT	16
#define RXFC_FS_MASK	(0x7f << RXFC_FS_SHIFT)

/* Rx FIFO 0/1 Status (RXF0S/RXF1S) */
#define RXFS_RFL	BIT(25)
#define RXFS_FF		BIT(24)
#define RXFS_FPI_SHIFT	16
#define RXFS_FPI_MASK	0x3f0000
#define RXFS_FGI_SHIFT	8
#define RXFS_FGI_MASK	0x3f00
#define RXFS_FFL_MASK	0x7f
#define RXFS_FFL_MASK_ELEMENTS	0x7f

/* Rx Buffer / FIFO Element Size Configuration (RXESC) */
#define M_CAN_RXESC_8BYTES	0x0
#define M_CAN_RXESC_64BYTES	0x777

/* Tx Buffer Configuration(TXBC) */
#define TXBC_NDTB_SHIFT		16
#define TXBC_NDTB_MASK		(0x3f << TXBC_NDTB_SHIFT)
#define TXBC_TFQS_SHIFT		24
#define TXBC_TFQS_MASK		(0x3f << TXBC_TFQS_SHIFT)

/* Tx FIFO/Queue Status (TXFQS) */
#define TXFQS_TFQF		BIT(21)
#define TXFQS_TFQPI_SHIFT	16
#define TXFQS_TFQPI_MASK	(0x1f << TXFQS_TFQPI_SHIFT)
#define TXFQS_TFGI_SHIFT	8
#define TXFQS_TFGI_MASK		(0x1f << TXFQS_TFGI_SHIFT)
#define TXFQS_TFFL_SHIFT	0
#define TXFQS_TFFL_MASK		(0x3f << TXFQS_TFFL_SHIFT)

/* Tx Buffer Element Size Configuration(TXESC) */
#define TXESC_TBDS_8BYTES	0x0
#define TXESC_TBDS_64BYTES	0x7

/* Tx Event FIFO Configuration (TXEFC) */
#define TXEFC_EFS_SHIFT		16
#define TXEFC_EFS_MASK		(0x3f << TXEFC_EFS_SHIFT)

/* Tx Event FIFO Status (TXEFS) */
#define TXEFS_TEFL		BIT(25)
#define TXEFS_EFF		BIT(24)
#define TXEFS_EFGI_SHIFT	8
#define	TXEFS_EFGI_MASK		(0x1f << TXEFS_EFGI_SHIFT)
#define TXEFS_EFFL_SHIFT	0
#define TXEFS_EFFL_MASK		(0x3f << TXEFS_EFFL_SHIFT)

/* Tx Event FIFO Acknowledge (TXEFA) */
#define TXEFA_EFAI_SHIFT	0
#define TXEFA_EFAI_MASK		(0x1f << TXEFA_EFAI_SHIFT)

/* Message RAM Configuration (in bytes) */
#define SIDF_ELEMENT_SIZE	4
#define XIDF_ELEMENT_SIZE	8
#define RXF0_ELEMENT_SIZE	72
#define RXF1_ELEMENT_SIZE	72
#define RXB_ELEMENT_SIZE	72
#define TXE_ELEMENT_SIZE	8
#define TXB_ELEMENT_SIZE	72

/* Message RAM Elements */
#define M_CAN_FIFO_ID		0x0
#define M_CAN_FIFO_DLC		0x4
#define M_CAN_FIFO_DATA(n)	(0x8 + ((n) << 2))

/* Rx Buffer Element */
/* R0 */
#define RX_BUF_ESI		BIT(31)
#define RX_BUF_XTD		BIT(30)
#define RX_BUF_RTR		BIT(29)
/* R1 */
#define RX_BUF_ANMF		BIT(31)
#define RX_BUF_FDF		BIT(21)
#define RX_BUF_BRS		BIT(20)

/* Tx Buffer Element */
/* T0 */
#define TX_BUF_ESI		BIT(31)
#define TX_BUF_XTD		BIT(30)
#define TX_BUF_RTR		BIT(29)
/* T1 */
#define TX_BUF_EFC		BIT(23)
#define TX_BUF_FDF		BIT(21)
#define TX_BUF_BRS		BIT(20)
#define TX_BUF_MM_SHIFT		24
#define TX_BUF_MM_MASK		(0xff << TX_BUF_MM_SHIFT)

/* Tx event FIFO Element */
/* E1 */
#define TX_EVENT_MM_SHIFT	TX_BUF_MM_SHIFT
#define TX_EVENT_MM_MASK	(0xff << TX_EVENT_MM_SHIFT)

#define IR_ALL_INT_CUSTOM_NO_TX (IR_ALL_INT & ~(IR_TEFL | IR_TEFF | IR_TEFN | IR_TCF | IR_TC | IR_TFE | IR_TEFW | IR_PED))

static inline u32 m_can_read(struct m_can_classdev *cdev, enum m_can_reg reg)
{
	return cdev->ops->read_reg(cdev, reg);
}

static inline void m_can_write(struct m_can_classdev *cdev, enum m_can_reg reg,
		u32 val)
{
	cdev->ops->write_reg(cdev, reg, val);
}

static u32 m_can_fifo_read(struct m_can_classdev *cdev,
		u32 fgi, unsigned int offset)
{
	u32 addr_offset = cdev->mcfg[MRAM_RXF0].off + fgi * RXF0_ELEMENT_SIZE +
		offset;

	return cdev->ops->read_fifo(cdev, addr_offset);
}

static void m_can_fifo_write(struct m_can_classdev *cdev,
		u32 fpi, unsigned int offset, u32 val)
{
	u32 addr_offset = cdev->mcfg[MRAM_TXB].off + fpi * TXB_ELEMENT_SIZE +
		offset;

	cdev->ops->write_fifo(cdev, addr_offset, val);
}

static inline void m_can_fifo_write_no_off(struct m_can_classdev *cdev,
		u32 fpi, u32 val)
{
	cdev->ops->write_fifo(cdev, fpi, val);
}

static u32 m_can_txe_fifo_read(struct m_can_classdev *cdev, u32 fgi, u32 offset)
{
	u32 addr_offset = cdev->mcfg[MRAM_TXE].off + fgi * TXE_ELEMENT_SIZE +
		offset;

	return cdev->ops->read_fifo(cdev, addr_offset);
}

static inline bool m_can_tx_fifo_full(struct m_can_classdev *cdev)
{
	return !!(m_can_read(cdev, M_CAN_TXFQS) & TXFQS_TFQF);
}

void m_can_config_endisable(struct m_can_classdev *cdev, bool enable)
{
	u32 cccr = m_can_read(cdev, M_CAN_CCCR);
	u32 timeout = 10;
	u32 val = 0;

	/* Clear the Clock stop request if it was set */
	if (cccr & CCCR_CSR)
		cccr &= ~CCCR_CSR;
		
	if (enable) {
		/* Clear the Clock stop request if it was set */
		if (cccr & CCCR_CSR)
			cccr &= ~CCCR_CSR;

		/* enable m_can configuration */
		m_can_write(cdev, M_CAN_CCCR, cccr | CCCR_INIT);
		udelay(5);
		/* CCCR.CCE can only be set/reset while CCCR.INIT = '1' */
		m_can_write(cdev, M_CAN_CCCR, cccr | CCCR_INIT | CCCR_CCE);
	} else {
		m_can_write(cdev, M_CAN_CCCR, cccr & ~(CCCR_INIT | CCCR_CCE));
	}
	/* there's a delay for module initialization */
	if (enable)
		val = CCCR_INIT | CCCR_CCE;

	while ((m_can_read(cdev, M_CAN_CCCR) & (CCCR_INIT | CCCR_CCE)) != val) {
		if (timeout == 0) {
			netdev_warn(cdev->net, "Failed to init module\n");
			return;
		}
		timeout--;
		udelay(1);
	}
}

static inline void m_can_enable_all_interrupts(struct m_can_classdev *cdev)
{
	/* Only interrupt line 0 is used in this driver */
	m_can_write(cdev, M_CAN_ILE, ILE_EINT0);
}

static inline void m_can_disable_all_interrupts(struct m_can_classdev *cdev)
{
	m_can_write(cdev, M_CAN_ILE, 0x0);
}

#if 0
int m_can_rx_clear(struct net_device *dev)
{
        struct m_can_classdev *cdev = netdev_priv(dev);
        m_can_disable_all_interrupts(cdev);
        m_can_rx_peripheral(dev);

        return 0;
}
EXPORT_SYMBOL_GPL(m_can_rx_clear);
#endif
static void m_can_clean(struct net_device *net)
{
	struct m_can_classdev *cdev = netdev_priv(net);

	if (cdev->tx_skb) {
		int putidx = 0;

		net->stats.tx_errors++;
		if (cdev->version > 30)
			putidx = ((m_can_read(cdev, M_CAN_TXFQS) &
						TXFQS_TFQPI_MASK) >> TXFQS_TFQPI_SHIFT);
		cdev->tx_skb = NULL;
	}
}

static void m_can_read_fifo(struct net_device *dev, u32 rxfs)
{
	struct net_device_stats *stats = &dev->stats;
	struct m_can_classdev *cdev = netdev_priv(dev);
	struct canfd_frame *cf;
	struct sk_buff *skb;
	u32 id, fgi, dlc;
	int i;

	/* calculate the fifo get index for where to read data */
	fgi = (rxfs & RXFS_FGI_MASK) >> RXFS_FGI_SHIFT;
	dlc = m_can_fifo_read(cdev, fgi, M_CAN_FIFO_DLC);
	if (dlc & RX_BUF_FDF)
		skb = alloc_canfd_skb(dev, &cf);
	else
		skb = alloc_can_skb(dev, (struct can_frame **)&cf);
	if (!skb) {
		stats->rx_dropped++;
		return;
	}

	if (dlc & RX_BUF_FDF)
		cf->len = can_fd_dlc2len((dlc >> 16) & 0x0F);
	else
		cf->len = can_cc_dlc2len((dlc >> 16) & 0x0F);

	id = m_can_fifo_read(cdev, fgi, M_CAN_FIFO_ID);
	if (id & RX_BUF_XTD)
		cf->can_id = (id & CAN_EFF_MASK) | CAN_EFF_FLAG;
	else
		cf->can_id = (id >> 18) & CAN_SFF_MASK;

	if (id & RX_BUF_ESI) {
		cf->flags |= CANFD_ESI;
		netdev_dbg(dev, "ESI Error\n");
	}

	if (!(dlc & RX_BUF_FDF) && (id & RX_BUF_RTR)) {
		cf->can_id |= CAN_RTR_FLAG;
	} else {
		if (dlc & RX_BUF_BRS)
			cf->flags |= CANFD_BRS;

		for (i = 0; i < cf->len; i += 4)
			*(u32 *)(cf->data + i) =
				m_can_fifo_read(cdev, fgi,
						M_CAN_FIFO_DATA(i / 4));
	}

	/* acknowledge rx fifo 0 */
	m_can_write(cdev, M_CAN_RXF0A, fgi);

	stats->rx_packets++;
	stats->rx_bytes += cf->len;

	netif_receive_skb(skb);
}

static int m_can_do_rx_poll(struct net_device *dev, int quota)
{
	struct m_can_classdev *cdev = netdev_priv(dev);
	u32 pkts = 0;
	u32 rxfs;

	rxfs = m_can_read(cdev, M_CAN_RXF0S);
	if (!(rxfs & RXFS_FFL_MASK)) {
		netdev_dbg(dev, "no messages in fifo0\n");
		return 0;
	}

	if(iw_mcan_prop)
	{
		quota = rxfs & RXFS_FFL_MASK_ELEMENTS;
	}

	while ((rxfs & RXFS_FFL_MASK) && (quota > 0)) {
		if (rxfs & RXFS_RFL)
			netdev_warn(dev, "Rx FIFO 0 Message Lost\n");

		m_can_read_fifo(dev, rxfs);

		quota--;
		pkts++;
		rxfs = m_can_read(cdev, M_CAN_RXF0S);
	}

	if (pkts)
		can_led_event(dev, CAN_LED_EVENT_RX);

	return pkts;
}

static int m_can_handle_lost_msg(struct net_device *dev)
{
	struct net_device_stats *stats = &dev->stats;
	struct sk_buff *skb;
	struct can_frame *frame;

	netdev_err(dev, "msg lost in rxf0\n");

	stats->rx_errors++;
	stats->rx_over_errors++;

	skb = alloc_can_err_skb(dev, &frame);
	if (unlikely(!skb))
		return 0;

	frame->can_id |= CAN_ERR_CRTL;
	frame->data[1] = CAN_ERR_CRTL_RX_OVERFLOW;

	netif_receive_skb(skb);

	return 1;
}

static int m_can_handle_lec_err(struct net_device *dev,
		enum m_can_lec_type lec_type)
{
	struct m_can_classdev *cdev = netdev_priv(dev);
	struct net_device_stats *stats = &dev->stats;
	struct can_frame *cf;
	struct sk_buff *skb;

	cdev->can.can_stats.bus_error++;
	stats->rx_errors++;

	/* propagate the error condition to the CAN stack */
	skb = alloc_can_err_skb(dev, &cf);
	if (unlikely(!skb))
		return 0;

	/* check for 'last error code' which tells us the
	 * type of the last error to occur on the CAN bus
	 */
	cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR;

	switch (lec_type) {
		case LEC_STUFF_ERROR:
			netdev_dbg(dev, "stuff error\n");
			cf->data[2] |= CAN_ERR_PROT_STUFF;
			break;
		case LEC_FORM_ERROR:
			netdev_dbg(dev, "form error\n");
			cf->data[2] |= CAN_ERR_PROT_FORM;
			break;
		case LEC_ACK_ERROR:
			netdev_dbg(dev, "ack error\n");
			cf->data[3] = CAN_ERR_PROT_LOC_ACK;
			break;
		case LEC_BIT1_ERROR:
			netdev_dbg(dev, "bit1 error\n");
			cf->data[2] |= CAN_ERR_PROT_BIT1;
			break;
		case LEC_BIT0_ERROR:
			netdev_dbg(dev, "bit0 error\n");
			cf->data[2] |= CAN_ERR_PROT_BIT0;
			break;
		case LEC_CRC_ERROR:
			netdev_dbg(dev, "CRC error\n");
			cf->data[3] = CAN_ERR_PROT_LOC_CRC_SEQ;
			break;
		default:
			break;
	}

	stats->rx_packets++;
	stats->rx_bytes += cf->can_dlc;
	netif_receive_skb(skb);

	return 1;
}

static int __m_can_get_berr_counter(const struct net_device *dev,
		struct can_berr_counter *bec)
{
	struct m_can_classdev *cdev = netdev_priv(dev);
	unsigned int ecr;

	ecr = m_can_read(cdev, M_CAN_ECR);
	bec->rxerr = (ecr & ECR_REC_MASK) >> ECR_REC_SHIFT;
	bec->txerr = (ecr & ECR_TEC_MASK) >> ECR_TEC_SHIFT;

	return 0;
}

static int m_can_clk_start(struct m_can_classdev *cdev)
{
	int err;

	if (cdev->pm_clock_support == 0)
		return 0;

	err = pm_runtime_get_sync(cdev->dev);
	if (err < 0) {
		pm_runtime_put_noidle(cdev->dev);
		return err;
	}

	return 0;
}

static void m_can_clk_stop(struct m_can_classdev *cdev)
{
	if (cdev->pm_clock_support)
		pm_runtime_put_sync(cdev->dev);
}

static int m_can_get_berr_counter(const struct net_device *dev,
		struct can_berr_counter *bec)
{
	struct m_can_classdev *cdev = netdev_priv(dev);
	int err;

	err = m_can_clk_start(cdev);
	if (err)
		return err;

	__m_can_get_berr_counter(dev, bec);

	m_can_clk_stop(cdev);

	return 0;
}

static int m_can_handle_state_change(struct net_device *dev,
		enum can_state new_state)
{
	struct m_can_classdev *cdev = netdev_priv(dev);
	struct net_device_stats *stats = &dev->stats;
	struct can_frame *cf;
	struct sk_buff *skb;
	struct can_berr_counter bec;
	unsigned int ecr;

	switch (new_state) {
		case CAN_STATE_ERROR_ACTIVE:
			/* error warning state */
			cdev->can.can_stats.error_warning++;
			cdev->can.state = CAN_STATE_ERROR_WARNING;
			break;
		case CAN_STATE_ERROR_PASSIVE:
			/* error passive state */
			cdev->can.can_stats.error_passive++;
			cdev->can.state = CAN_STATE_ERROR_PASSIVE;
			break;
		case CAN_STATE_BUS_OFF:
			/* bus-off state */
			cdev->can.state = CAN_STATE_BUS_OFF;
			m_can_disable_all_interrupts(cdev);
			cdev->can.can_stats.bus_off++;
			can_bus_off(dev);
			break;
		default:
			break;
	}

	/* propagate the error condition to the CAN stack */
	skb = alloc_can_err_skb(dev, &cf);
	if (unlikely(!skb))
		return 0;

	__m_can_get_berr_counter(dev, &bec);

	switch (new_state) {
		case CAN_STATE_ERROR_ACTIVE:
			/* error warning state */
			cf->can_id |= CAN_ERR_CRTL;
			cf->data[1] = (bec.txerr > bec.rxerr) ?
				CAN_ERR_CRTL_TX_WARNING :
				CAN_ERR_CRTL_RX_WARNING;
			cf->data[6] = bec.txerr;
			cf->data[7] = bec.rxerr;
			break;
		case CAN_STATE_ERROR_PASSIVE:
			/* error passive state */
			cf->can_id |= CAN_ERR_CRTL;
			ecr = m_can_read(cdev, M_CAN_ECR);
			if (ecr & ECR_RP)
				cf->data[1] |= CAN_ERR_CRTL_RX_PASSIVE;
			if (bec.txerr > 127)
				cf->data[1] |= CAN_ERR_CRTL_TX_PASSIVE;
			cf->data[6] = bec.txerr;
			cf->data[7] = bec.rxerr;
			break;
		case CAN_STATE_BUS_OFF:
			/* bus-off state */
			cf->can_id |= CAN_ERR_BUSOFF;
			break;
		default:
			break;
	}

	stats->rx_packets++;
	stats->rx_bytes += cf->can_dlc;
	netif_receive_skb(skb);

	return 1;
}

static int m_can_handle_state_errors(struct net_device *dev, u32 psr)
{
	struct m_can_classdev *cdev = netdev_priv(dev);
	int work_done = 0;

	if (psr & PSR_EW && cdev->can.state != CAN_STATE_ERROR_WARNING) {
		netdev_dbg(dev, "entered error warning state\n");
		work_done += m_can_handle_state_change(dev,
				CAN_STATE_ERROR_WARNING);
	}

	if (psr & PSR_EP && cdev->can.state != CAN_STATE_ERROR_PASSIVE) {
		netdev_dbg(dev, "entered error passive state\n");
		work_done += m_can_handle_state_change(dev,
				CAN_STATE_ERROR_PASSIVE);
	}

	if (psr & PSR_BO && cdev->can.state != CAN_STATE_BUS_OFF) {
		netdev_dbg(dev, "entered error bus off state\n");
		work_done += m_can_handle_state_change(dev,
				CAN_STATE_BUS_OFF);
	}

	return work_done;
}

static void m_can_handle_other_err(struct net_device *dev, u32 irqstatus)
{
	if (irqstatus & IR_WDI)
		netdev_err(dev, "Message RAM Watchdog event due to missing READY\n");
	if (irqstatus & IR_ELO)
		netdev_err(dev, "Error Logging Overflow\n");
	if (irqstatus & IR_BEU)
		netdev_err(dev, "Bit Error Uncorrected\n");
	if (irqstatus & IR_BEC)
		netdev_err(dev, "Bit Error Corrected\n");
	if (irqstatus & IR_TOO)
		netdev_err(dev, "Timeout reached\n");
	if (irqstatus & IR_MRAF)
		netdev_err(dev, "Message RAM access failure occurred\n");
}

static inline bool is_lec_err(u32 psr)
{
	psr &= LEC_UNUSED;

	return psr && (psr != LEC_UNUSED);
}

static int m_can_handle_bus_errors(struct net_device *dev, u32 irqstatus,
		u32 psr)
{
	struct m_can_classdev *cdev = netdev_priv(dev);
	int work_done = 0;

	if (irqstatus & IR_RF0L)
		work_done += m_can_handle_lost_msg(dev);

	/* handle lec errors on the bus */
	if ((cdev->can.ctrlmode & CAN_CTRLMODE_BERR_REPORTING) &&
			is_lec_err(psr))
		work_done += m_can_handle_lec_err(dev, psr & LEC_UNUSED);

	/* other unproccessed error interrupts */
	m_can_handle_other_err(dev, irqstatus);

	return work_done;
}

static int m_can_rx_handler_rx(struct net_device *dev, int quota)
{
	int work_done = 0;
	work_done += m_can_do_rx_poll(dev, (quota - work_done));
	return work_done;
		
}

static int m_can_rx_handler(struct net_device *dev, int quota)
{
	struct m_can_classdev *cdev = netdev_priv(dev);
	int work_done = 0;
	u32 irqstatus, psr;
	irqstatus = cdev->irqstatus | m_can_read(cdev, M_CAN_IR);
	if (!irqstatus)
		goto end;
	/* Errata workaround for issue "Needless activation of MRAF irq"
	 * During frame reception while the MCAN is in Error Passive state
	 * and the Receive Error Counter has the value MCAN_ECR.REC = 127,
	 * it may happen that MCAN_IR.MRAF is set although there was no
	 * Message RAM access failure.
	 * If MCAN_IR.MRAF is enabled, an interrupt to the Host CPU is generated
	 * The Message RAM Access Failure interrupt routine needs to check
	 * whether MCAN_ECR.RP = ’1’ and MCAN_ECR.REC = 127.
	 * In this case, reset MCAN_IR.MRAF. No further action is required.
	 */
	if (cdev->version <= 31 && irqstatus & IR_MRAF &&
			m_can_read(cdev, M_CAN_ECR) & ECR_RP) {
		struct can_berr_counter bec;

		__m_can_get_berr_counter(dev, &bec);
		if (bec.rxerr == 127) {
			m_can_write(cdev, M_CAN_IR, IR_MRAF);
			irqstatus &= ~IR_MRAF;
		}
	}

	psr = m_can_read(cdev, M_CAN_PSR);

	if (irqstatus & IR_ERR_STATE)
		work_done += m_can_handle_state_errors(dev, psr);
	if(iw_mcan_prop)
	{
		/* changes bus size from 30X to 31X*/
		if (irqstatus & IR_ERR_BUS_31X)
			work_done += m_can_handle_bus_errors(dev, irqstatus, psr);

		if (irqstatus & IR_RF0W)
			work_done += m_can_do_rx_poll(dev, (quota - work_done));
	}
	else /* iw_mcan_prop */
	{
		if (irqstatus & IR_ERR_BUS_30X)
			work_done += m_can_handle_bus_errors(dev, irqstatus, psr);

		if (irqstatus & IR_RF0N)
			work_done += m_can_do_rx_poll(dev, (quota - work_done));
	} /* iw_mcan_prop */
end:
	return work_done;
}

static int m_can_rx_peripheral(struct net_device *dev)
{
	struct m_can_classdev *cdev = netdev_priv(dev);

	m_can_rx_handler(dev, 1);

	m_can_enable_all_interrupts(cdev);

	return 0;
}

int m_can_rx_clear(struct net_device *dev)
{
        struct m_can_classdev *cdev = netdev_priv(dev);
        m_can_disable_all_interrupts(cdev);
        m_can_rx_peripheral(dev);

        return 0;
}
EXPORT_SYMBOL_GPL(m_can_rx_clear);

static int m_can_poll(struct napi_struct *napi, int quota)
{
	struct net_device *dev = napi->dev;
	struct m_can_classdev *cdev = netdev_priv(dev);
	int work_done;

	work_done = m_can_rx_handler(dev, quota);
	if (work_done < quota) {
		napi_complete_done(napi, work_done);
		m_can_enable_all_interrupts(cdev);
	}

	return work_done;
}


/* Set the "iw_mcan_prop" flag to execute iWave specific change */
void m_can_set_iw_mcan_prop_flag( void )
{
        iw_mcan_prop = true;
}
EXPORT_SYMBOL_GPL(m_can_set_iw_mcan_prop_flag);

static void m_can_echo_tx_event(struct net_device *dev)
{
	u32 fgi = 0;
	unsigned int msg_mark;

	struct m_can_classdev *cdev = netdev_priv(dev);
	struct net_device_stats *stats = &dev->stats;

	fgi = (m_can_read(cdev, M_CAN_TXEFS) & TXEFS_EFGI_MASK)
		>> TXEFS_EFGI_SHIFT;

	/* get message marker */
	msg_mark = (m_can_txe_fifo_read(cdev, fgi, 4) &
			TX_EVENT_MM_MASK) >> TX_EVENT_MM_SHIFT;

	/* ack txe element */
	m_can_write(cdev, M_CAN_TXEFA, (TXEFA_EFAI_MASK &
				(fgi << TXEFA_EFAI_SHIFT)));

	/* update stats */
	stats->tx_bytes += can_get_echo_skb(dev, msg_mark, NULL);
	stats->tx_packets++;
}

static int m_can_rx_peripheral_rx(struct net_device *dev)
{
	struct m_can_classdev *cdev = netdev_priv(dev);

	m_can_rx_handler_rx(dev, 1);

	m_can_enable_all_interrupts(cdev);
	return 0;
}

static irqreturn_t m_can_isr(int irq, void *dev_id)
{
	struct net_device *dev = (struct net_device *)dev_id;
	struct m_can_classdev *cdev = netdev_priv(dev);
	struct net_device_stats *stats = &dev->stats;
	u32 ir;
	ir = m_can_read(cdev, M_CAN_IR);
	/* ACK all irqs */
	if (ir & IR_ALL_INT_CUSTOM_NO_TX)
		m_can_write(cdev, M_CAN_IR, ir);

	cdev->ops->clear_interrupts(cdev);
	
	/* schedule NAPI in case of
	 * - rx IRQ
	 * - state change IRQ
	 * - bus error IRQ and bus error reporting
	 */
	if(ir == 0x0 || (ir & IR_RF0N)) /* Watchdog interrupt */
	{
		m_can_disable_all_interrupts(cdev);
		m_can_rx_peripheral_rx(dev);
		return IRQ_HANDLED;
	}
	
	if(iw_mcan_prop)
	{
		if ((ir & IR_RF0W) || (ir & IR_RF0N) || (ir & IR_ERR_ALL_30X)) {
			cdev->irqstatus = ir;
			m_can_disable_all_interrupts(cdev);
			if (!cdev->is_peripheral)
				napi_schedule(&cdev->napi);
			else
				m_can_rx_peripheral(dev);
		}
	}
	else /* iw_mcan_prop */
	{
		if ((ir & IR_RF0N) || (ir & IR_ERR_ALL_30X)) {
			cdev->irqstatus = ir;
			m_can_disable_all_interrupts(cdev);
			if (!cdev->is_peripheral)
				napi_schedule(&cdev->napi);
			else
				m_can_rx_peripheral(dev);
		}
	} /* iw_mcan_prop */
	/*if (cdev->version == 30) {
		if (ir & IR_TC) {
			/  Transmission Complete Interrupt /
			stats->tx_bytes += can_get_echo_skb(dev, 0, NULL);
			stats->tx_packets++;
			can_led_event(dev, CAN_LED_EVENT_TX);
			netif_wake_queue(dev);
		}
	} else  {
		if (ir & IR_TFE) 
		{
			netif_wake_queue(dev);
		}
	}*/
	return IRQ_HANDLED;
}

static const struct can_bittiming_const m_can_bittiming_const_30X = {
	.name = KBUILD_MODNAME,
	.tseg1_min = 2,		/* Time segment 1 = prop_seg + phase_seg1 */
	.tseg1_max = 64,
	.tseg2_min = 1,		/* Time segment 2 = phase_seg2 */
	.tseg2_max = 16,
	.sjw_max = 16,
	.brp_min = 1,
	.brp_max = 1024,
	.brp_inc = 1,
};

static const struct can_bittiming_const m_can_data_bittiming_const_30X = {
	.name = KBUILD_MODNAME,
	.tseg1_min = 2,		/* Time segment 1 = prop_seg + phase_seg1 */
	.tseg1_max = 16,
	.tseg2_min = 1,		/* Time segment 2 = phase_seg2 */
	.tseg2_max = 8,
	.sjw_max = 4,
	.brp_min = 1,
	.brp_max = 32,
	.brp_inc = 1,
};

static const struct can_bittiming_const m_can_bittiming_const_31X = {
	.name = KBUILD_MODNAME,
	.tseg1_min = 2,		/* Time segment 1 = prop_seg + phase_seg1 */
	.tseg1_max = 256,
	.tseg2_min = 1,		/* Time segment 2 = phase_seg2 */
	.tseg2_max = 128,
	.sjw_max = 128,
	.brp_min = 1,
	.brp_max = 512,
	.brp_inc = 1,
};

static const struct can_bittiming_const m_can_data_bittiming_const_31X = {
	.name = KBUILD_MODNAME,
	.tseg1_min = 1,		/* Time segment 1 = prop_seg + phase_seg1 */
	.tseg1_max = 32,
	.tseg2_min = 1,		/* Time segment 2 = phase_seg2 */
	.tseg2_max = 16,
	.sjw_max = 16,
	.brp_min = 1,
	.brp_max = 32,
	.brp_inc = 1,
};

static int m_can_set_bittiming(struct net_device *dev)
{
	struct m_can_classdev *cdev = netdev_priv(dev);
	const struct can_bittiming *bt = &cdev->can.bittiming;
	const struct can_bittiming *dbt = &cdev->can.data_bittiming;
	u16 brp, sjw, tseg1, tseg2;
	u32 reg_btp;

	brp = bt->brp - 1;
	sjw = bt->sjw - 1;
	tseg1 = bt->prop_seg + bt->phase_seg1 - 1;
	tseg2 = bt->phase_seg2 - 1;
	reg_btp = (brp << NBTP_NBRP_SHIFT) | (sjw << NBTP_NSJW_SHIFT) |
		(tseg1 << NBTP_NTSEG1_SHIFT) | (tseg2 << NBTP_NTSEG2_SHIFT);
	m_can_write(cdev, M_CAN_NBTP, reg_btp);
	Tx_DELAY = 0;

	if (cdev->can.ctrlmode & CAN_CTRLMODE_FD) {
		reg_btp = 0;
		brp = dbt->brp - 1;
		sjw = dbt->sjw - 1;
		tseg1 = dbt->prop_seg + dbt->phase_seg1 - 1;
		tseg2 = dbt->phase_seg2 - 1;
		FD_mode = true;

		/* TDC is only needed for bitrates beyond 2.5 MBit/s.
		 * This is mentioned in the "Bit Time Requirements for CAN FD"
		 * paper presented at the International CAN Conference 2013
		 */
		if (dbt->bitrate > 1000000) {
			u32 tdco, ssp;

			/* Use the same value of secondary sampling point
			 * as the data sampling point
			 */
			ssp = dbt->sample_point;

			/* Equation based on Bosch's M_CAN User Manual's
			 * Transmitter Delay Compensation Section
			 */
			tdco = (cdev->can.clock.freq / 1000) *
				ssp / dbt->bitrate;
			/* Max valid TDCO value is 127 */
			if (tdco > 127) {
				netdev_warn(dev, "TDCO value of %u is beyond maximum. Using maximum possible value\n",
						tdco);
				tdco = 127;
			}

			reg_btp |= DBTP_TDC;
			m_can_write(cdev, M_CAN_TDCR,
					tdco << TDCR_TDCO_SHIFT);
		}

		reg_btp |= (brp << DBTP_DBRP_SHIFT) |
			(sjw << DBTP_DSJW_SHIFT) |
			(tseg1 << DBTP_DTSEG1_SHIFT) |
			(tseg2 << DBTP_DTSEG2_SHIFT);

		m_can_write(cdev, M_CAN_DBTP, reg_btp);
	}
	else
	{
		switch (bt->bitrate)
		{
			case 1000000:
				Tx_DELAY = 0;
				break;
		}
	}

	return 0;
}


/* Configure M_CAN chip:
 * - set rx buffer/fifo element size
 * - configure rx fifo
 * - accept non-matching frame into fifo 0
 * - configure tx buffer
 *		- >= v3.1.x: TX FIFO is used
 * - configure mode
 * - setup bittiming
 */
static void m_can_chip_config(struct net_device *dev)
{
	struct m_can_classdev *cdev = netdev_priv(dev);
	u32 cccr, test;
	int k;

	/* RX Buffer/FIFO Element Size 64 bytes data field */
	m_can_write(cdev, M_CAN_RXESC, M_CAN_RXESC_64BYTES);

	/* Accept Non-matching Frames Into FIFO 0 */
	m_can_write(cdev, M_CAN_GFC, 0x0);

	if (cdev->version == 30) {
		/* only support one Tx Buffer currently */
		m_can_write(cdev, M_CAN_TXBC, (1 << TXBC_NDTB_SHIFT) |
				cdev->mcfg[MRAM_TXB].off);
	} else {
		/* TX FIFO is used for newer IP Core versions */
		m_can_write(cdev, M_CAN_TXBC,
				(cdev->mcfg[MRAM_TXB].num << TXBC_TFQS_SHIFT) |
				(cdev->mcfg[MRAM_TXB].off));
	}

	/* support 64 bytes payload */
	m_can_write(cdev, M_CAN_TXESC, TXESC_TBDS_64BYTES);

	/* TX Event FIFO */
	if (cdev->version == 30) {
		m_can_write(cdev, M_CAN_TXEFC, (1 << TXEFC_EFS_SHIFT) |
				cdev->mcfg[MRAM_TXE].off);
	} else {
		/* Full TX Event FIFO is used */
		m_can_write(cdev, M_CAN_TXEFC,
				((cdev->mcfg[MRAM_TXE].num << TXEFC_EFS_SHIFT)
				 & TXEFC_EFS_MASK) |
				cdev->mcfg[MRAM_TXE].off);
	}
	
	if (iw_mcan_prop)
	{
		/* rx fifo configuration, blocking mode, fifo size 1 */
		m_can_write(cdev, M_CAN_RXF0C,
				(cdev->mcfg[MRAM_RXF0].num << RXFC_FS_SHIFT) |
				cdev->mcfg[MRAM_RXF0].off | 0x9A000000 /*| 0x81200000*/);
		//Added by iwave
		k = cdev->mcfg[MRAM_RXF0].num << RXFC_FS_SHIFT | cdev->mcfg[MRAM_RXF0].off ;

		m_can_write(cdev, M_CAN_RXF1C,
				(cdev->mcfg[MRAM_RXF1].num << RXFC_FS_SHIFT) |
				cdev->mcfg[MRAM_RXF1].off | 0x8C000000 /*| 0x81200000 */);
	}
	else /* iw_mcan_prop */
	{
		/* rx fifo configuration, blocking mode, fifo size 1 */
		m_can_write(cdev, M_CAN_RXF0C,
				(cdev->mcfg[MRAM_RXF0].num << RXFC_FS_SHIFT) |
				cdev->mcfg[MRAM_RXF0].off);

		m_can_write(cdev, M_CAN_RXF1C,
				(cdev->mcfg[MRAM_RXF1].num << RXFC_FS_SHIFT) |
				cdev->mcfg[MRAM_RXF1].off);
	} /* iw_mcan_prop */
	
	cccr = m_can_read(cdev, M_CAN_CCCR);
	test = m_can_read(cdev, M_CAN_TEST);
	test &= ~TEST_LBCK;
	if (cdev->version == 30) {
		/* Version 3.0.x */

		cccr &= ~(CCCR_TEST | CCCR_MON |
				(CCCR_CMR_MASK << CCCR_CMR_SHIFT) |
				(CCCR_CME_MASK << CCCR_CME_SHIFT));

		if (cdev->can.ctrlmode & CAN_CTRLMODE_FD)
			cccr |= CCCR_CME_CANFD_BRS << CCCR_CME_SHIFT;

	} else {
		/* Version 3.1.x or 3.2.x */
		cccr &= ~(CCCR_TEST | CCCR_MON | CCCR_BRSE | CCCR_FDOE |
				CCCR_NISO);

		/* Only 3.2.x has NISO Bit implemented */
		if (cdev->can.ctrlmode & CAN_CTRLMODE_FD_NON_ISO)
			cccr |= CCCR_NISO;

		if (cdev->can.ctrlmode & CAN_CTRLMODE_FD)
			cccr |= (CCCR_BRSE | CCCR_FDOE);
	}

	/* Enable Monitoring (all versions) */
	if (cdev->can.ctrlmode & CAN_CTRLMODE_LISTENONLY)
		cccr |= CCCR_MON;

	/* Write config */
	m_can_write(cdev, M_CAN_CCCR, cccr);
	m_can_write(cdev, M_CAN_TEST, test);

	/* Enable interrupts */
	m_can_write(cdev, M_CAN_IR, IR_ALL_INT);
	if (!(cdev->can.ctrlmode & CAN_CTRLMODE_BERR_REPORTING))
		if (cdev->version == 30)
			m_can_write(cdev, M_CAN_IE, IR_ALL_INT &
					~(IR_ERR_LEC_30X));
		else
			m_can_write(cdev, M_CAN_IE, IR_ALL_INT_CUSTOM_NO_TX &
					~(IR_ERR_LEC_31X));
	else
		m_can_write(cdev, M_CAN_IE, IR_ALL_INT_CUSTOM_NO_TX);

	/* route all interrupts to INT0 */
	m_can_write(cdev, M_CAN_ILS, ILS_ALL_INT0);

	/* set bittiming params */
	m_can_set_bittiming(dev);
	
	m_can_config_endisable(cdev, false);
	mode=true;

	if (cdev->ops->init)
		cdev->ops->init(cdev);
}

static void m_can_start(struct net_device *dev)
{
	struct m_can_classdev *cdev = netdev_priv(dev);

	/* basic m_can configuration */
	m_can_chip_config(dev);

	cdev->can.state = CAN_STATE_ERROR_ACTIVE;

	m_can_enable_all_interrupts(cdev);
}

static int m_can_set_mode(struct net_device *dev, enum can_mode mode)
{
	switch (mode) {
		case CAN_MODE_START:
			m_can_clean(dev);
			m_can_start(dev);
			netif_wake_queue(dev);
			break;
		default:
			return -EOPNOTSUPP;
	}

	return 0;
}

/* Checks core release number of M_CAN
 * returns 0 if an unsupported device is detected
 * else it returns the release and step coded as:
 * return value = 10 * <release> + 1 * <step>
 */
static int m_can_check_core_release(struct m_can_classdev *cdev)
{
	u32 crel_reg;
	u8 rel;
	u8 step;
	int res;

	/* Read Core Release Version and split into version number
	 * Example: Version 3.2.1 => rel = 3; step = 2; substep = 1;
	 */
	crel_reg = m_can_read(cdev, M_CAN_CREL);
	rel = (u8)((crel_reg & CREL_REL_MASK) >> CREL_REL_SHIFT);
	step = (u8)((crel_reg & CREL_STEP_MASK) >> CREL_STEP_SHIFT);

	if (rel == 3) {
		/* M_CAN v3.x.y: create return value */
		res = 30 + step;
	} else {
		/* Unsupported M_CAN version */
		res = 0;
	}

	return res;
}

/* Selectable Non ISO support only in version 3.2.x
 * This function checks if the bit is writable.
 */
static bool m_can_niso_supported(struct m_can_classdev *cdev)
{
	u32 cccr_reg, cccr_poll = 0;
	int niso_timeout = -ETIMEDOUT;
	int i;

	cccr_reg = m_can_read(cdev, M_CAN_CCCR);
	cccr_reg |= CCCR_NISO;
	m_can_write(cdev, M_CAN_CCCR, cccr_reg);

	for (i = 0; i <= 10; i++) {
		cccr_poll = m_can_read(cdev, M_CAN_CCCR);
		if (cccr_poll == cccr_reg) {
			niso_timeout = 0;
			break;
		}

		usleep_range(1, 5);
	}

	/* Clear NISO */
	cccr_reg &= ~(CCCR_NISO);
	m_can_write(cdev, M_CAN_CCCR, cccr_reg | CCCR_FDOE | CCCR_BRSE);


	/* return false if time out (-ETIMEDOUT), else return true */
	return !niso_timeout;
}

static int m_can_dev_setup(struct m_can_classdev *m_can_dev)
{
	struct net_device *dev = m_can_dev->net;
	int m_can_version;

	m_can_version = m_can_check_core_release(m_can_dev);
	/* return if unsupported version */
	if (!m_can_version) {
		dev_err(m_can_dev->dev, "Unsupported version number: %2d",
				m_can_version);
		return -EINVAL;
	}

	if (!m_can_dev->is_peripheral)
		netif_napi_add(dev, &m_can_dev->napi,
				m_can_poll, M_CAN_NAPI_WEIGHT);

	/* Shared properties of all M_CAN versions */
	m_can_dev->version = m_can_version;
	m_can_dev->can.do_set_mode = m_can_set_mode;
	m_can_dev->can.do_get_berr_counter = m_can_get_berr_counter;

	/* Set M_CAN supported operations */
	m_can_dev->can.ctrlmode_supported = /*CAN_CTRLMODE_LOOPBACK |*/
		CAN_CTRLMODE_LISTENONLY |
		CAN_CTRLMODE_BERR_REPORTING |
		CAN_CTRLMODE_FD;

	/* Set properties depending on M_CAN version */
	switch (m_can_dev->version) {
		case 30:
			/* CAN_CTRLMODE_FD_NON_ISO is fixed with M_CAN IP v3.0.x */
			can_set_static_ctrlmode(dev, CAN_CTRLMODE_FD_NON_ISO);
			m_can_dev->can.bittiming_const = m_can_dev->bit_timing ?
				m_can_dev->bit_timing : &m_can_bittiming_const_30X;

			m_can_dev->can.data_bittiming_const = m_can_dev->data_timing ?
				m_can_dev->data_timing :
				&m_can_data_bittiming_const_30X;
			break;
		case 31:
			/* CAN_CTRLMODE_FD_NON_ISO is fixed with M_CAN IP v3.1.x */
			can_set_static_ctrlmode(dev, CAN_CTRLMODE_FD_NON_ISO);
			m_can_dev->can.bittiming_const = m_can_dev->bit_timing ?
				m_can_dev->bit_timing : &m_can_bittiming_const_31X;

			m_can_dev->can.data_bittiming_const = m_can_dev->data_timing ?
				m_can_dev->data_timing :
				&m_can_data_bittiming_const_31X;
			break;
		case 32:
			m_can_dev->can.bittiming_const = m_can_dev->bit_timing ?
				m_can_dev->bit_timing : &m_can_bittiming_const_31X;

			m_can_dev->can.data_bittiming_const = m_can_dev->data_timing ?
				m_can_dev->data_timing :
				&m_can_data_bittiming_const_31X;
			m_can_dev->can.ctrlmode_supported |=
				(m_can_niso_supported(m_can_dev)
				 ? CAN_CTRLMODE_FD_NON_ISO
				 : 0);
			break;
		default:
			dev_err(m_can_dev->dev, "Unsupported version number: %2d",
					m_can_dev->version);
			return -EINVAL;
	}

	if (m_can_dev->ops->init)
		m_can_dev->ops->init(m_can_dev);

	return 0;
}

static void m_can_stop(struct net_device *dev)
{
	struct m_can_classdev *cdev = netdev_priv(dev);

	/* disable all interrupts */
	m_can_disable_all_interrupts(cdev);

	/* set the state as STOPPED */
	cdev->can.state = CAN_STATE_STOPPED;
}

static int m_can_close(struct net_device *dev)
{
	struct m_can_classdev *cdev = netdev_priv(dev);

	netif_stop_queue(dev);

	if (!cdev->is_peripheral)
		napi_disable(&cdev->napi);

	m_can_stop(dev);
	m_can_clk_stop(cdev);
	free_irq(dev->irq, dev);

	if (cdev->is_peripheral) {
		cdev->tx_skb = NULL;
		destroy_workqueue(cdev->tx_wq);
		cdev->tx_wq = NULL;
	}

	close_candev(dev);
	can_led_event(dev, CAN_LED_EVENT_STOP);

	return 0;
}

static int m_can_next_echo_skb_occupied(struct net_device *dev, int putidx)
{
	struct m_can_classdev *cdev = netdev_priv(dev);
	/*get wrap around for loopback skb index */
	unsigned int wrap = cdev->can.echo_skb_max;
	int next_idx;
	/* calculate next index */
	next_idx = (++putidx >= wrap ? 0 : putidx);

	/* check if occupied */
	return !!cdev->can.echo_skb[next_idx];
}
void printBinary(unsigned int num);
void printBinary(unsigned int num) {
    int i;
    for (i = 31; i >= 0; i--) {
        printk(KERN_CONT "%d", (num >> i) & 1);
        if (i % 4 == 0) // add space for better readability
            printk(KERN_CONT " ");
    }
    printk(KERN_CONT "\n");
}

static netdev_tx_t m_can_tx_handler(struct m_can_classdev *cdev)
{
	struct canfd_frame *cf = (struct canfd_frame *)cdev->tx_skb->data;
	struct net_device *dev = cdev->net;
	struct sk_buff *skb = cdev->tx_skb;
	const struct can_bittiming *bt = &cdev->can.bittiming;
	const struct can_bittiming *dbt = &cdev->can.data_bittiming;
	u32 id, cccr, fdflags;
	int i;
	int putidx;
	bool FD_29_bit;
	printk("handler begining---------------------\n");	
	/* Generate ID field for TX buffer Element */
	/* Common to all supported M_CAN versions */
	   if (!cdev || !skb) {
	        printk(KERN_ERR "Invalid parameters\n");
        	return NETDEV_TX_BUSY;
	   }
	if (cf->can_id & CAN_EFF_FLAG) { /* 29 bit identifier */
		id = cf->can_id & CAN_EFF_MASK;
		id |= TX_BUF_XTD;
		if(FD_mode == false && bt->bitrate !=1000000)
		{
			switch (bt->bitrate)
			{
				case 250000:
					Tx_DELAY = 350;
					break;
				case 500000:
					Tx_DELAY = 80;
					break;
			}
		}
		else
		{
			FD_29_bit = true;
		}
	} else { /* 11 bit identifier */
		id = ((cf->can_id & CAN_SFF_MASK) << 18);
		printk("11th bit identifier");
		if(FD_mode == false && bt->bitrate !=1000000)
		{
			switch (bt->bitrate)
			{
				case 250000:
					Tx_DELAY = 270;
					break;
				case 500000:
					Tx_DELAY = 40;
					break;
			}
		}
		else
		{
			FD_29_bit = false;
		}
	}

	if (cf->can_id & CAN_RTR_FLAG)
		printk("inside RTR FLAG------------\n");
		id |= TX_BUF_RTR;

	if (cdev->version == 30) {
		netif_stop_queue(dev);
		printk("inside cdev version------------------\n");

		/* message ram configuration */
		m_can_fifo_write(cdev, 0, M_CAN_FIFO_ID, id);
		m_can_fifo_write(cdev, 0, M_CAN_FIFO_DLC,
				can_fd_len2dlc(cf->len) << 16);

		for (i = 0; i < cf->len; i += 4)
			m_can_fifo_write(cdev, 0,
					M_CAN_FIFO_DATA(i / 4),
					*(u32 *)(cf->data + i));
			printk("inside can fifo write--------------------\n");

		can_put_echo_skb(skb, dev, 0,0);

		if (cdev->can.ctrlmode & CAN_CTRLMODE_FD) {
			cccr = m_can_read(cdev, M_CAN_CCCR);
			cccr &= ~(CCCR_CMR_MASK << CCCR_CMR_SHIFT);
			if (can_is_canfd_skb(skb)) {
				if (cf->flags & CANFD_BRS)
					cccr |= CCCR_CMR_CANFD_BRS <<
						CCCR_CMR_SHIFT;
				else
					cccr |= CCCR_CMR_CANFD <<
						CCCR_CMR_SHIFT;
			} else {
				cccr |= CCCR_CMR_CAN << CCCR_CMR_SHIFT;
			}
			m_can_write(cdev, M_CAN_CCCR, cccr);
		}
		m_can_write(cdev, M_CAN_TXBTIE, 0x1);
		m_can_write(cdev, M_CAN_TXBAR, 0x1);
		/* End of xmit function for version 3.0.x */
	} else {
		/* Transmit routine for version >= v3.1.x */
		/* get put index for frame */
		printk("else part of version----------------\n");
		putidx = ((m_can_read(cdev, M_CAN_TXFQS) & TXFQS_TFQPI_MASK)
				>> TXFQS_TFQPI_SHIFT);

		printk("putidx " );			// to print refgister name
		printBinary(putidx);	
		
		int errcr;
		errcr = m_can_read(cdev, M_CAN_TXFQS);  //to read register
		printk("M_CAN_TXFQS" );			// to print refgister name
		printBinary(errcr);

		errcr = m_can_read(cdev, M_CAN_FIFO_ID);  //to read register
                printk("M_CAN_FIFO_ID,------------" );                 // to print refgister name
                printBinary(errcr);

		/* Write ID Field to FIFO Element */
		m_can_fifo_write(cdev, putidx, M_CAN_FIFO_ID, id);

		 errcr = m_can_read(cdev, M_CAN_FIFO_ID);  //to read register
                printk("After---- M_CAN_FIFO_ID,------------" );                 // to print refgister name
                printBinary(errcr);


		/* get CAN FD configuration of frame */
		fdflags = 0;
		if (can_is_canfd_skb(skb)) {
			printk("CANfd configuration frame\n");
			fdflags |= TX_BUF_FDF;
			if (cf->flags & CANFD_BRS)
				fdflags |= TX_BUF_BRS;
		}

		/* Construct DLC Field. Also contains CAN-FD configuration
		 * use put index of fifo as message marker
		 * it is used in TX interrupt for
		 * sending the correct echo frame
		 */
		printk("before fifo write----------------------------\n");
		m_can_fifo_write(cdev, putidx, M_CAN_FIFO_DLC,
				((putidx << TX_BUF_MM_SHIFT) &
				 TX_BUF_MM_MASK) |
				(can_fd_len2dlc(cf->len) << 16) |
				fdflags | TX_BUF_EFC);
		printk("after fifo write-----------------------------\n");

		for (i = 0; i < cf->len; i += 4)
			printk("inside for loop fifo write-------------------------\n");
			m_can_fifo_write(cdev, putidx, M_CAN_FIFO_DATA(i / 4),
					*(u32 *)(cf->data + i));
		printk("beg of delay-------------------------------\n");
		if(FD_mode == true && (dbt->bitrate <= 1000000 || bt->bitrate <= 250000))
		{
	
			if(FD_29_bit == true)
			{
				printk("inside delay---------------\n");
				if(i==64)
				{
					switch(bt->bitrate)
					{
						case 250000:
							switch(dbt->bitrate)
							{
								case 250000:
									Tx_DELAY = 1960;
									break;
								case 500000:
									Tx_DELAY = 840;
									break;
								case 1000000:
									Tx_DELAY = 270;
									break;
							}
							break;
						case 500000:
							switch(dbt->bitrate)
							{
								case 500000:
									Tx_DELAY = 740;
									break;
								case 1000000:
									Tx_DELAY = 170;
									break;
							}
							break;
						case 1000000:
							switch(dbt->bitrate)
							{
								case 1000000:
									Tx_DELAY = 120;
									break;
							}
							break;
					}
				}
				else
				{
					switch(bt->bitrate)
					{
						case 250000:
							switch(dbt->bitrate)
							{
								case 250000:
									Tx_DELAY = 400;
									break;
								case 500000:
									Tx_DELAY = 200;
									break;
								case 1000000:
									Tx_DELAY = 100;
									break;
								case 2000000:
									Tx_DELAY = 60;
									break;
								case 4000000:
									Tx_DELAY = 30;
									break;
								case 5000000:
									Tx_DELAY = 40;
									break;
								default:
									Tx_DELAY = 45;
									break;
							}
							break;
						case 500000:
							switch(dbt->bitrate)
							{
								case 500000:
									Tx_DELAY = 110;
									break;
								case 1000000:
									Tx_DELAY = 10;
									break;
							}
							break;
						case 1000000:
							switch(dbt->bitrate)
							{
								case 1000000:
									Tx_DELAY = 0;
									break;
							}
							break;
					}
				}
			}
			else
			{
				if(i==64)
				{
					switch(bt->bitrate)
					{
						case 250000:
							switch(dbt->bitrate)
							{
								case 250000:
									Tx_DELAY = 1880;
									break;
								case 500000:
									Tx_DELAY = 760;
									break;
								case 1000000:
									Tx_DELAY = 190;
									break;
							}
							break;
						case 500000:
							switch(dbt->bitrate)
							{
								case 500000:
									Tx_DELAY = 700;
									break;
								case 1000000:
									Tx_DELAY = 140;
									break;
							}
							break;
						case 1000000:
							switch(dbt->bitrate)
							{
								case 1000000:
									Tx_DELAY = 110;
									break;
							}
							break;
					}
				}
				else
				{
					switch(bt->bitrate)
					{
						case 250000:
							switch(dbt->bitrate)
							{
								case 250000:
									Tx_DELAY = 330;
									break;
								case 500000:
									Tx_DELAY = 120;
									break;
								case 1000000:
									Tx_DELAY = 25;
									break;
							}
							break;
						case 500000:
							switch(dbt->bitrate)
							{
								case 500000:
									Tx_DELAY = 70;
									break;
								case 1000000:
									Tx_DELAY = 0;
									break;
							}
							break;
						case 1000000:
							switch(dbt->bitrate)
							{
								case 1000000:
									Tx_DELAY = 0;
									break;
							}
							break;
					}
				}
			}
		}
		printk("end of delay--------------------------\n");
		/* Push loopback echo.
		 * Will be looped back on TX interrupt based on message marker
		 */
		can_put_echo_skb(skb, dev, putidx,0);

		/* Enable TX FIFO element to start transfer  */
		m_can_write(cdev, M_CAN_TXBAR, (1 << putidx));
		if (m_can_tx_fifo_full(cdev) )
		{
			printk("already full------------------\n");
			netif_wake_queue(dev);
			//Don't start the network and enable Transmit FIFO enable interrupt
			m_can_write(cdev, M_CAN_IE, IR_ALL_INT_CUSTOM_NO_TX);
		}
		else
		{
			netif_wake_queue(dev);
			printk("not full------------\n");
		}
		cdev->tx_skb = NULL;
	}
	
	return NETDEV_TX_OK;
}

static void m_can_tx_work_queue(struct work_struct *ws)
{
	struct m_can_classdev *cdev = container_of(ws, struct m_can_classdev,
			tx_work);

	m_can_tx_handler(cdev);
	cdev->tx_skb = NULL;
}

static netdev_tx_t m_can_start_xmit(struct sk_buff *skb,
		struct net_device *dev)
{
	struct m_can_classdev *cdev = netdev_priv(dev);

	if (cdev->is_peripheral) {
		if (cdev->tx_skb) {
			//netdev_err(dev, "hard_xmit called while tx busy\n");
			return NETDEV_TX_BUSY;
		}

		if (cdev->can.state == CAN_STATE_BUS_OFF) {
			m_can_clean(dev);
		} else {
			/* Need to stop the queue to avoid numerous requests
			 * from being sent.  Suggested improvement is to create
			 * a queueing mechanism that will queue the skbs and
			 * process them in order.
			 */
			printk("begining-----\n");
			udelay(Tx_DELAY);
			cdev->tx_skb = skb;
			netif_stop_queue(cdev->net);
//			queue_work(cdev->tx_wq, &cdev->tx_work);
			return m_can_tx_handler(cdev);
			printk("ending----------\n");
		}
	} else {
		cdev->tx_skb = skb;
		return m_can_tx_handler(cdev);
	}

	return NETDEV_TX_OK;
}

static int m_can_open(struct net_device *dev)
{
	struct m_can_classdev *cdev = netdev_priv(dev);
	int err;

	err = m_can_clk_start(cdev);
	if (err)
		return err;
	/* open the can device */
	err = open_candev(dev);
	if (err) {
		netdev_err(dev, "failed to open can device\n");
		goto exit_disable_clks;
	}
	/* register interrupt handler */
	if (cdev->is_peripheral) {
		cdev->tx_skb = NULL;
		cdev->tx_wq = alloc_workqueue("mcan_wq",
				WQ_FREEZABLE | WQ_MEM_RECLAIM, 0);
		if (!cdev->tx_wq) {
			err = -ENOMEM;
			goto out_wq_fail;
		}

		INIT_WORK(&cdev->tx_work, m_can_tx_work_queue);

		err = request_threaded_irq(dev->irq, NULL, m_can_isr,
				IRQF_ONESHOT | IRQF_TRIGGER_FALLING,
				dev->name, dev);
	} else {
		err = request_irq(dev->irq, m_can_isr, IRQF_SHARED, dev->name,
				dev);
	}

	if (err < 0) {
		netdev_err(dev, "failed to request interrupt\n");
		goto exit_irq_fail;
	}

	/* start the m_can controller */
	m_can_start(dev);

	can_led_event(dev, CAN_LED_EVENT_OPEN);

	if (!cdev->is_peripheral)
		napi_enable(&cdev->napi);

	netif_start_queue(dev);

	return 0;

exit_irq_fail:
	if (cdev->is_peripheral)
		destroy_workqueue(cdev->tx_wq);
out_wq_fail:
	close_candev(dev);
exit_disable_clks:
	m_can_clk_stop(cdev);
	return err;
}

static const struct net_device_ops m_can_netdev_ops = {
	.ndo_open = m_can_open,
	.ndo_stop = m_can_close,
	.ndo_start_xmit = m_can_start_xmit,
	.ndo_change_mtu = can_change_mtu,
};

static int register_m_can_dev(struct net_device *dev)
{
	//dev->flags |= IFF_ECHO;	/* we support local echo 
	dev->netdev_ops = &m_can_netdev_ops;

	return register_candev(dev);
}

static void m_can_of_parse_mram(struct m_can_classdev *cdev,
		const u32 *mram_config_vals)
{
	cdev->mcfg[MRAM_SIDF].off = mram_config_vals[0];
	cdev->mcfg[MRAM_SIDF].num = mram_config_vals[1];
	cdev->mcfg[MRAM_XIDF].off = cdev->mcfg[MRAM_SIDF].off +
		cdev->mcfg[MRAM_SIDF].num * SIDF_ELEMENT_SIZE;
	cdev->mcfg[MRAM_XIDF].num = mram_config_vals[2];
	cdev->mcfg[MRAM_RXF0].off = cdev->mcfg[MRAM_XIDF].off +
		cdev->mcfg[MRAM_XIDF].num * XIDF_ELEMENT_SIZE;
	cdev->mcfg[MRAM_RXF0].num = mram_config_vals[3] &
		(RXFC_FS_MASK >> RXFC_FS_SHIFT);
	cdev->mcfg[MRAM_RXF1].off = cdev->mcfg[MRAM_RXF0].off +
		cdev->mcfg[MRAM_RXF0].num * RXF0_ELEMENT_SIZE;
	cdev->mcfg[MRAM_RXF1].num = mram_config_vals[4] &
		(RXFC_FS_MASK >> RXFC_FS_SHIFT);
	cdev->mcfg[MRAM_RXB].off = cdev->mcfg[MRAM_RXF1].off +
		cdev->mcfg[MRAM_RXF1].num * RXF1_ELEMENT_SIZE;
	cdev->mcfg[MRAM_RXB].num = mram_config_vals[5];
	cdev->mcfg[MRAM_TXE].off = cdev->mcfg[MRAM_RXB].off +
		cdev->mcfg[MRAM_RXB].num * RXB_ELEMENT_SIZE;
	cdev->mcfg[MRAM_TXE].num = mram_config_vals[6];
	cdev->mcfg[MRAM_TXB].off = cdev->mcfg[MRAM_TXE].off +
		cdev->mcfg[MRAM_TXE].num * TXE_ELEMENT_SIZE;
	cdev->mcfg[MRAM_TXB].num = mram_config_vals[7] &
		(TXBC_NDTB_MASK >> TXBC_NDTB_SHIFT);

	dev_dbg(cdev->dev,
			"sidf 0x%x %d xidf 0x%x %d rxf0 0x%x %d rxf1 0x%x %d rxb 0x%x %d txe 0x%x %d txb 0x%x %d\n",
			cdev->mcfg[MRAM_SIDF].off, cdev->mcfg[MRAM_SIDF].num,
			cdev->mcfg[MRAM_XIDF].off, cdev->mcfg[MRAM_XIDF].num,
			cdev->mcfg[MRAM_RXF0].off, cdev->mcfg[MRAM_RXF0].num,
			cdev->mcfg[MRAM_RXF1].off, cdev->mcfg[MRAM_RXF1].num,
			cdev->mcfg[MRAM_RXB].off, cdev->mcfg[MRAM_RXB].num,
			cdev->mcfg[MRAM_TXE].off, cdev->mcfg[MRAM_TXE].num,
			cdev->mcfg[MRAM_TXB].off, cdev->mcfg[MRAM_TXB].num);
}

void m_can_init_ram(struct m_can_classdev *cdev)
{
	int end, i, start;
	/* initialize the entire Message RAM in use to avoid possible
	 * ECC/parity checksum errors when reading an uninitialized buffer
	 */
	if(mode==false)
	{
		m_can_config_endisable(cdev, true);
	}
	if(mode==true)
	{
		mode=false;
	}
	start = cdev->mcfg[MRAM_SIDF].off;
	end = cdev->mcfg[MRAM_TXB].off +
		cdev->mcfg[MRAM_TXB].num * TXB_ELEMENT_SIZE;

	for (i = start; i < end; i += 4)
		m_can_fifo_write_no_off(cdev, i, 0x0);	
}
EXPORT_SYMBOL_GPL(m_can_init_ram);

int m_can_class_get_clocks(struct m_can_classdev *m_can_dev)
{
	int ret = 0;

	m_can_dev->hclk = devm_clk_get(m_can_dev->dev, "hclk");
	m_can_dev->cclk = devm_clk_get(m_can_dev->dev, "cclk");

	if (IS_ERR(m_can_dev->cclk)) {
		dev_err(m_can_dev->dev, "no clock found\n");
		ret = -ENODEV;
	}

	return ret;
}
EXPORT_SYMBOL_GPL(m_can_class_get_clocks);

struct m_can_classdev *m_can_class_allocate_dev(struct device *dev)
{
	struct m_can_classdev *class_dev = NULL;
	u32 mram_config_vals[MRAM_CFG_LEN];
	struct net_device *net_dev;
	u32 tx_fifo_size;
	int ret;

	ret = fwnode_property_read_u32_array(dev_fwnode(dev),
			"bosch,mram-cfg",
			mram_config_vals,
			sizeof(mram_config_vals) / 4);
	if (ret) {
		dev_err(dev, "Could not get Message RAM configuration.");
		goto out;
	}

	/* Get TX FIFO size
	 * Defines the total amount of echo buffers for loopback
	 */
	tx_fifo_size = mram_config_vals[7];

	/* allocate the m_can device */
	net_dev = alloc_candev(sizeof(*class_dev), tx_fifo_size);
	if (!net_dev) {
		dev_err(dev, "Failed to allocate CAN device");
		goto out;
	}

	class_dev = netdev_priv(net_dev);
	if (!class_dev) {
		dev_err(dev, "Failed to init netdev cdevate");
		goto out;
	}

	class_dev->net = net_dev;
	class_dev->dev = dev;
	SET_NETDEV_DEV(net_dev, dev);

	m_can_of_parse_mram(class_dev, mram_config_vals);
out:
	return class_dev;
}
EXPORT_SYMBOL_GPL(m_can_class_allocate_dev);

int m_can_class_register(struct m_can_classdev *m_can_dev)
{
	int ret;

	if (m_can_dev->pm_clock_support) {
		pm_runtime_enable(m_can_dev->dev);
		ret = m_can_clk_start(m_can_dev);
		if (ret)
			goto pm_runtime_fail;
	}

	ret = m_can_dev_setup(m_can_dev);
	if (ret)
		goto clk_disable;

	ret = register_m_can_dev(m_can_dev->net);
	if (ret) {
		dev_err(m_can_dev->dev, "registering %s failed (err=%d)\n",
				m_can_dev->net->name, ret);
		goto clk_disable;
	}

	devm_can_led_init(m_can_dev->net);

	of_can_transceiver(m_can_dev->net);

	dev_info(m_can_dev->dev, "%s device registered (irq=%d, version=%d)\n",
			KBUILD_MODNAME, m_can_dev->net->irq, m_can_dev->version);

	/* Probe finished
	 * Stop clocks. They will be reactivated once the M_CAN device is opened
	 */
clk_disable:
	m_can_clk_stop(m_can_dev);
pm_runtime_fail:
	if (ret) {
		if (m_can_dev->pm_clock_support)
			pm_runtime_disable(m_can_dev->dev);
		free_candev(m_can_dev->net);
	}

	return ret;
}
EXPORT_SYMBOL_GPL(m_can_class_register);

int m_can_class_suspend(struct device *dev)
{
	struct net_device *ndev = dev_get_drvdata(dev);
	struct m_can_classdev *cdev = netdev_priv(ndev);

	if (netif_running(ndev)) {
		netif_stop_queue(ndev);
		netif_device_detach(ndev);
		m_can_stop(ndev);
		m_can_clk_stop(cdev);
	}

	pinctrl_pm_select_sleep_state(dev);

	cdev->can.state = CAN_STATE_SLEEPING;

	return 0;
}
EXPORT_SYMBOL_GPL(m_can_class_suspend);

int m_can_class_resume(struct device *dev)
{
	struct net_device *ndev = dev_get_drvdata(dev);
	struct m_can_classdev *cdev = netdev_priv(ndev);

	pinctrl_pm_select_default_state(dev);

	cdev->can.state = CAN_STATE_ERROR_ACTIVE;

	if (netif_running(ndev)) {
		int ret;

		ret = m_can_clk_start(cdev);
		if (ret)
			return ret;

		m_can_init_ram(cdev);
		m_can_start(ndev);
		netif_device_attach(ndev);
		netif_start_queue(ndev);
	}

	return 0;
}
EXPORT_SYMBOL_GPL(m_can_class_resume);

void m_can_class_unregister(struct m_can_classdev *m_can_dev)
{
	unregister_candev(m_can_dev->net);

	m_can_clk_stop(m_can_dev);

	free_candev(m_can_dev->net);
}
EXPORT_SYMBOL_GPL(m_can_class_unregister);

void m_can_disable_rx_irq(struct m_can_classdev *m_can_dev)
{
        iw_ie_reg = m_can_read(m_can_dev, M_CAN_IE);
        m_can_write(m_can_dev, M_CAN_IE, iw_ie_reg & 0xFFFFFE00);
}
EXPORT_SYMBOL_GPL(m_can_disable_rx_irq);

void m_can_enable_rx_irq(struct m_can_classdev *m_can_dev)
{
        m_can_write(m_can_dev, M_CAN_IE, iw_ie_reg);
}
EXPORT_SYMBOL_GPL(m_can_enable_rx_irq);

MODULE_AUTHOR("Dong Aisheng <b29396@freescale.com>");
MODULE_AUTHOR("Dan Murphy <dmurphy@ti.com>");
MODULE_LICENSE("GPL v2");
MODULE_DESCRIPTION("CAN bus driver for Bosch M_CAN controller");