// SPDX-License-Identifier: GPL-2.0
/* NXP TJA1100 BroadRReach PHY driver
 *
 * Copyright (C) 2018 Marek Vasut <marex@denx.de>
 */
#include <linux/delay.h>
#include <linux/ethtool.h>
#include <linux/kernel.h>
#include <linux/mii.h>
#include <linux/module.h>
#include <linux/phy.h>
#include <linux/hwmon.h>
#include <linux/bitfield.h>

#define PHY_ID_MASK			0xfffffff0
#define PHY_ID_TJA1100			0x0180dc40
#define PHY_ID_TJA1101			0x0180dd00

#define MII_ECTRL			17
#define MII_ECTRL_LINK_CONTROL		BIT(15)
#define MII_ECTRL_POWER_MODE_MASK	GENMASK(14, 11)
#define MII_ECTRL_POWER_MODE_NO_CHANGE	(0x0 << 11)
#define MII_ECTRL_POWER_MODE_NORMAL	(0x3 << 11)
#define MII_ECTRL_POWER_MODE_STANDBY	(0xc << 11)
#define MII_ECTRL_CONFIG_EN		BIT(2)
#define MII_ECTRL_WAKE_REQUEST		BIT(0)

#define MII_CFG1			18
#define MII_CFG1_AUTO_OP		BIT(14)
#define MII_CFG1_SLEEP_CONFIRM		BIT(6)
#define MII_CFG1_LED_MODE_MASK		GENMASK(5, 4)
#define MII_CFG1_LED_MODE_LINKUP	0
#define MII_CFG1_LED_ENABLE		BIT(3)

#define MII_CFG2			19
#define MII_CFG2_SLEEP_REQUEST_TO	GENMASK(1, 0)
#define MII_CFG2_SLEEP_REQUEST_TO_16MS	0x3

#define MII_INTSRC			21
#define MII_INTSRC_TEMP_ERR		BIT(1)
#define MII_INTSRC_UV_ERR		BIT(3)

#define MII_COMMSTAT			23
#define MII_COMMSTAT_LINK_UP		BIT(15)

#define MII_GENSTAT			24
#define MII_GENSTAT_PLL_LOCKED		BIT(14)

#define MII_COMMCFG			27
#define MII_COMMCFG_AUTO_OP		BIT(15)

struct tja11xx_priv {
	char		*hwmon_name;
	struct device	*hwmon_dev;
};

struct tja11xx_phy_stats {
	const char	*string;
	u8		reg;
	u8		off;
	u16		mask;
};

static struct tja11xx_phy_stats tja11xx_hw_stats[] = {
	{ "phy_symbol_error_count", 20, 0, GENMASK(15, 0) },
	{ "phy_polarity_detect", 25, 6, BIT(6) },
	{ "phy_open_detect", 25, 7, BIT(7) },
	{ "phy_short_detect", 25, 8, BIT(8) },
	{ "phy_rem_rcvr_count", 26, 0, GENMASK(7, 0) },
	{ "phy_loc_rcvr_count", 26, 8, GENMASK(15, 8) },
};

static int tja11xx_check(struct phy_device *phydev, u8 reg, u16 mask, u16 set)
{
	int i, ret;

	for (i = 0; i < 200; i++) {
		ret = phy_read(phydev, reg);
		if (ret < 0)
			return ret;

		if ((ret & mask) == set)
			return 0;

		usleep_range(100, 150);
	}

	return -ETIMEDOUT;
}

static int phy_modify_check(struct phy_device *phydev, u8 reg,
			    u16 mask, u16 set)
{
	int ret;

	ret = phy_modify(phydev, reg, mask, set);
	if (ret)
		return ret;

	return tja11xx_check(phydev, reg, mask, set);
}

static int tja11xx_enable_reg_write(struct phy_device *phydev)
{
	return phy_set_bits(phydev, MII_ECTRL, MII_ECTRL_CONFIG_EN);
}

static int tja11xx_enable_link_control(struct phy_device *phydev)
{
	return phy_set_bits(phydev, MII_ECTRL, MII_ECTRL_LINK_CONTROL);
}

static int tja11xx_wakeup(struct phy_device *phydev)
{
	int ret;

	ret = phy_read(phydev, MII_ECTRL);
	if (ret < 0)
		return ret;

	switch (ret & MII_ECTRL_POWER_MODE_MASK) {
	case MII_ECTRL_POWER_MODE_NO_CHANGE:
		break;
	case MII_ECTRL_POWER_MODE_NORMAL:
		ret = phy_set_bits(phydev, MII_ECTRL, MII_ECTRL_WAKE_REQUEST);
		if (ret)
			return ret;

		ret = phy_clear_bits(phydev, MII_ECTRL, MII_ECTRL_WAKE_REQUEST);
		if (ret)
			return ret;
		break;
	case MII_ECTRL_POWER_MODE_STANDBY:
		ret = phy_modify_check(phydev, MII_ECTRL,
				       MII_ECTRL_POWER_MODE_MASK,
				       MII_ECTRL_POWER_MODE_STANDBY);
		if (ret)
			return ret;

		ret = phy_modify(phydev, MII_ECTRL, MII_ECTRL_POWER_MODE_MASK,
				 MII_ECTRL_POWER_MODE_NORMAL);
		if (ret)
			return ret;

		ret = phy_modify_check(phydev, MII_GENSTAT,
				       MII_GENSTAT_PLL_LOCKED,
				       MII_GENSTAT_PLL_LOCKED);
		if (ret)
			return ret;

		return tja11xx_enable_link_control(phydev);
	default:
		break;
	}

	return 0;
}

static int tja11xx_soft_reset(struct phy_device *phydev)
{
	int ret;

	ret = tja11xx_enable_reg_write(phydev);
	if (ret)
		return ret;

	return genphy_soft_reset(phydev);
}

static int tja11xx_config_init(struct phy_device *phydev)
{
	int ret;

	ret = tja11xx_enable_reg_write(phydev);
	if (ret)
		return ret;

	phydev->autoneg = AUTONEG_DISABLE;
	phydev->speed = SPEED_100;
	phydev->duplex = DUPLEX_FULL;

	switch (phydev->phy_id & PHY_ID_MASK) {
	case PHY_ID_TJA1100:
		ret = phy_modify(phydev, MII_CFG1,
				 MII_CFG1_AUTO_OP | MII_CFG1_LED_MODE_MASK |
				 MII_CFG1_LED_ENABLE,
				 MII_CFG1_AUTO_OP | MII_CFG1_LED_MODE_LINKUP |
				 MII_CFG1_LED_ENABLE);
		if (ret)
			return ret;
		break;
	case PHY_ID_TJA1101:
		ret = phy_set_bits(phydev, MII_COMMCFG, MII_COMMCFG_AUTO_OP);
		if (ret)
			return ret;
		break;
	default:
		return -EINVAL;
	}

	ret = phy_clear_bits(phydev, MII_CFG1, MII_CFG1_SLEEP_CONFIRM);
	if (ret)
		return ret;

	ret = phy_modify(phydev, MII_CFG2, MII_CFG2_SLEEP_REQUEST_TO,
			 MII_CFG2_SLEEP_REQUEST_TO_16MS);
	if (ret)
		return ret;

	ret = tja11xx_wakeup(phydev);
	if (ret < 0)
		return ret;

	/* ACK interrupts by reading the status register */
	ret = phy_read(phydev, MII_INTSRC);
	if (ret < 0)
		return ret;

	return 0;
}

static int tja11xx_read_status(struct phy_device *phydev)
{
	int ret;

	ret = genphy_update_link(phydev);
	if (ret)
		return ret;

	if (phydev->link) {
		ret = phy_read(phydev, MII_COMMSTAT);
		if (ret < 0)
			return ret;

		if (!(ret & MII_COMMSTAT_LINK_UP))
			phydev->link = 0;
	}

	return 0;
}

static int tja11xx_get_sset_count(struct phy_device *phydev)
{
	return ARRAY_SIZE(tja11xx_hw_stats);
}

static void tja11xx_get_strings(struct phy_device *phydev, u8 *data)
{
	int i;

	for (i = 0; i < ARRAY_SIZE(tja11xx_hw_stats); i++) {
		strncpy(data + i * ETH_GSTRING_LEN,
			tja11xx_hw_stats[i].string, ETH_GSTRING_LEN);
	}
}

static void tja11xx_get_stats(struct phy_device *phydev,
			      struct ethtool_stats *stats, u64 *data)
{
	int i, ret;

	for (i = 0; i < ARRAY_SIZE(tja11xx_hw_stats); i++) {
		ret = phy_read(phydev, tja11xx_hw_stats[i].reg);
		if (ret < 0)
			data[i] = U64_MAX;
		else {
			data[i] = ret & tja11xx_hw_stats[i].mask;
			data[i] >>= tja11xx_hw_stats[i].off;
		}
	}
}

static int tja11xx_hwmon_read(struct device *dev,
			      enum hwmon_sensor_types type,
			      u32 attr, int channel, long *value)
{
	struct phy_device *phydev = dev_get_drvdata(dev);
	int ret;

	if (type == hwmon_in && attr == hwmon_in_lcrit_alarm) {
		ret = phy_read(phydev, MII_INTSRC);
		if (ret < 0)
			return ret;

		*value = !!(ret & MII_INTSRC_TEMP_ERR);
		return 0;
	}

	if (type == hwmon_temp && attr == hwmon_temp_crit_alarm) {
		ret = phy_read(phydev, MII_INTSRC);
		if (ret < 0)
			return ret;

		*value = !!(ret & MII_INTSRC_UV_ERR);
		return 0;
	}

	return -EOPNOTSUPP;
}

static umode_t tja11xx_hwmon_is_visible(const void *data,
					enum hwmon_sensor_types type,
					u32 attr, int channel)
{
	if (type == hwmon_in && attr == hwmon_in_lcrit_alarm)
		return 0444;

	if (type == hwmon_temp && attr == hwmon_temp_crit_alarm)
		return 0444;

	return 0;
}

static const struct hwmon_channel_info *tja11xx_hwmon_info[] = {
	HWMON_CHANNEL_INFO(in, HWMON_I_LCRIT_ALARM),
	HWMON_CHANNEL_INFO(temp, HWMON_T_CRIT_ALARM),
	NULL
};

static const struct hwmon_ops tja11xx_hwmon_hwmon_ops = {
	.is_visible	= tja11xx_hwmon_is_visible,
	.read		= tja11xx_hwmon_read,
};

static const struct hwmon_chip_info tja11xx_hwmon_chip_info = {
	.ops		= &tja11xx_hwmon_hwmon_ops,
	.info		= tja11xx_hwmon_info,
};

static int tja11xx_probe(struct phy_device *phydev)
{
	struct device *dev = &phydev->mdio.dev;
	struct tja11xx_priv *priv;
	int i;

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

	priv->hwmon_name = devm_kstrdup(dev, dev_name(dev), GFP_KERNEL);
	if (!priv->hwmon_name)
		return -ENOMEM;

	for (i = 0; priv->hwmon_name[i]; i++)
		if (hwmon_is_bad_char(priv->hwmon_name[i]))
			priv->hwmon_name[i] = '_';

	priv->hwmon_dev =
		devm_hwmon_device_register_with_info(dev, priv->hwmon_name,
						     phydev,
						     &tja11xx_hwmon_chip_info,
						     NULL);

	return PTR_ERR_OR_ZERO(priv->hwmon_dev);
}

static struct phy_driver tja11xx_driver[] = {
	{
		PHY_ID_MATCH_MODEL(PHY_ID_TJA1100),
		.name		= "NXP TJA1100",
		.features       = PHY_BASIC_T1_FEATURES,
		.probe		= tja11xx_probe,
		.soft_reset	= tja11xx_soft_reset,
		.config_init	= tja11xx_config_init,
		.read_status	= tja11xx_read_status,
		.suspend	= genphy_suspend,
		.resume		= genphy_resume,
		.set_loopback   = genphy_loopback,
		/* Statistics */
		.get_sset_count = tja11xx_get_sset_count,
		.get_strings	= tja11xx_get_strings,
		.get_stats	= tja11xx_get_stats,
	}, {
		PHY_ID_MATCH_MODEL(PHY_ID_TJA1101),
		.name		= "NXP TJA1101",
		.features       = PHY_BASIC_T1_FEATURES,
		.probe		= tja11xx_probe,
		.soft_reset	= tja11xx_soft_reset,
		.config_init	= tja11xx_config_init,
		.read_status	= tja11xx_read_status,
		.suspend	= genphy_suspend,
		.resume		= genphy_resume,
		.set_loopback   = genphy_loopback,
		/* Statistics */
		.get_sset_count = tja11xx_get_sset_count,
		.get_strings	= tja11xx_get_strings,
		.get_stats	= tja11xx_get_stats,
	}
};

module_phy_driver(tja11xx_driver);

static struct mdio_device_id __maybe_unused tja11xx_tbl[] = {
	{ PHY_ID_MATCH_MODEL(PHY_ID_TJA1100) },
	{ PHY_ID_MATCH_MODEL(PHY_ID_TJA1101) },
	{ }
};

MODULE_DEVICE_TABLE(mdio, tja11xx_tbl);

MODULE_AUTHOR("Marek Vasut <marex@denx.de>");
MODULE_DESCRIPTION("NXP TJA11xx BoardR-Reach PHY driver");
MODULE_LICENSE("GPL");