// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * BCM6328 USBH PHY Controller Driver
 *
 * Copyright (C) 2020 Álvaro Fernández Rojas <noltari@gmail.com>
 * Copyright (C) 2015 Simon Arlott
 *
 * Derived from bcm963xx_4.12L.06B_consumer/kernel/linux/arch/mips/bcm963xx/setup.c:
 * Copyright (C) 2002 Broadcom Corporation
 *
 * Derived from OpenWrt patches:
 * Copyright (C) 2013 Jonas Gorski <jonas.gorski@gmail.com>
 * Copyright (C) 2013 Florian Fainelli <f.fainelli@gmail.com>
 * Copyright (C) 2008 Maxime Bizon <mbizon@freebox.fr>
 */

#include <linux/clk.h>
#include <linux/io.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/phy/phy.h>
#include <linux/platform_device.h>
#include <linux/reset.h>

/* USBH control register offsets */
enum usbh_regs {
	USBH_BRT_CONTROL1 = 0,
	USBH_BRT_CONTROL2,
	USBH_BRT_STATUS1,
	USBH_BRT_STATUS2,
	USBH_UTMI_CONTROL1,
#define   USBH_UC1_DEV_MODE_SEL		BIT(0)
	USBH_TEST_PORT_CONTROL,
	USBH_PLL_CONTROL1,
#define   USBH_PLLC_REFCLKSEL_SHIFT	0
#define   USBH_PLLC_REFCLKSEL_MASK	(0x3 << USBH_PLLC_REFCLKSEL_SHIFT)
#define   USBH_PLLC_CLKSEL_SHIFT	2
#define   USBH_PLLC_CLKSEL_MASK		(0x3 << USBH_PLLC_CLKSEL_MASK)
#define   USBH_PLLC_XTAL_PWRDWNB	BIT(4)
#define   USBH_PLLC_PLL_PWRDWNB		BIT(5)
#define   USBH_PLLC_PLL_CALEN		BIT(6)
#define   USBH_PLLC_PHYPLL_BYP		BIT(7)
#define   USBH_PLLC_PLL_RESET		BIT(8)
#define   USBH_PLLC_PLL_IDDQ_PWRDN	BIT(9)
#define   USBH_PLLC_PLL_PWRDN_DELAY	BIT(10)
#define   USBH_6318_PLLC_PLL_SUSPEND_EN	BIT(27)
#define   USBH_6318_PLLC_PHYPLL_BYP	BIT(29)
#define   USBH_6318_PLLC_PLL_RESET	BIT(30)
#define   USBH_6318_PLLC_PLL_IDDQ_PWRDN	BIT(31)
	USBH_SWAP_CONTROL,
#define   USBH_SC_OHCI_DATA_SWAP	BIT(0)
#define   USBH_SC_OHCI_ENDIAN_SWAP	BIT(1)
#define   USBH_SC_OHCI_LOGICAL_ADDR_EN	BIT(2)
#define   USBH_SC_EHCI_DATA_SWAP	BIT(3)
#define   USBH_SC_EHCI_ENDIAN_SWAP	BIT(4)
#define   USBH_SC_EHCI_LOGICAL_ADDR_EN	BIT(5)
#define   USBH_SC_USB_DEVICE_SEL	BIT(6)
	USBH_GENERIC_CONTROL,
#define   USBH_GC_PLL_SUSPEND_EN	BIT(1)
	USBH_FRAME_ADJUST_VALUE,
	USBH_SETUP,
#define   USBH_S_IOC			BIT(4)
#define   USBH_S_IPP			BIT(5)
	USBH_MDIO,
	USBH_MDIO32,
	USBH_USB_SIM_CONTROL,
#define   USBH_USC_LADDR_SEL		BIT(5)

	__USBH_ENUM_SIZE
};

struct bcm63xx_usbh_phy_variant {
	/* Registers */
	long regs[__USBH_ENUM_SIZE];

	/* PLLC bits to set/clear for power on */
	u32 power_pllc_clr;
	u32 power_pllc_set;

	/* Setup bits to set/clear for power on */
	u32 setup_clr;
	u32 setup_set;

	/* Swap Control bits to set */
	u32 swapctl_dev_set;

	/* Test Port Control value to set if non-zero */
	u32 tpc_val;

	/* USB Sim Control bits to set */
	u32 usc_set;

	/* UTMI Control 1 bits to set */
	u32 utmictl1_dev_set;
};

struct bcm63xx_usbh_phy {
	void __iomem *base;
	struct clk *usbh_clk;
	struct clk *usb_ref_clk;
	struct reset_control *reset;
	const struct bcm63xx_usbh_phy_variant *variant;
	bool device_mode;
};

static const struct bcm63xx_usbh_phy_variant usbh_bcm6318 = {
	.regs = {
		[USBH_BRT_CONTROL1] = -1,
		[USBH_BRT_CONTROL2] = -1,
		[USBH_BRT_STATUS1] = -1,
		[USBH_BRT_STATUS2] = -1,
		[USBH_UTMI_CONTROL1] = 0x2c,
		[USBH_TEST_PORT_CONTROL] = 0x1c,
		[USBH_PLL_CONTROL1] = 0x04,
		[USBH_SWAP_CONTROL] = 0x0c,
		[USBH_GENERIC_CONTROL] = -1,
		[USBH_FRAME_ADJUST_VALUE] = 0x08,
		[USBH_SETUP] = 0x00,
		[USBH_MDIO] = 0x14,
		[USBH_MDIO32] = 0x18,
		[USBH_USB_SIM_CONTROL] = 0x20,
	},
	.power_pllc_clr = USBH_6318_PLLC_PLL_IDDQ_PWRDN,
	.power_pllc_set = USBH_6318_PLLC_PLL_SUSPEND_EN,
	.setup_set = USBH_S_IOC,
	.swapctl_dev_set = USBH_SC_USB_DEVICE_SEL,
	.usc_set = USBH_USC_LADDR_SEL,
	.utmictl1_dev_set = USBH_UC1_DEV_MODE_SEL,
};

static const struct bcm63xx_usbh_phy_variant usbh_bcm6328 = {
	.regs = {
		[USBH_BRT_CONTROL1] = 0x00,
		[USBH_BRT_CONTROL2] = 0x04,
		[USBH_BRT_STATUS1] = 0x08,
		[USBH_BRT_STATUS2] = 0x0c,
		[USBH_UTMI_CONTROL1] = 0x10,
		[USBH_TEST_PORT_CONTROL] = 0x14,
		[USBH_PLL_CONTROL1] = 0x18,
		[USBH_SWAP_CONTROL] = 0x1c,
		[USBH_GENERIC_CONTROL] = 0x20,
		[USBH_FRAME_ADJUST_VALUE] = 0x24,
		[USBH_SETUP] = 0x28,
		[USBH_MDIO] = 0x2c,
		[USBH_MDIO32] = 0x30,
		[USBH_USB_SIM_CONTROL] = 0x34,
	},
	.setup_set = USBH_S_IOC,
	.swapctl_dev_set = USBH_SC_USB_DEVICE_SEL,
	.utmictl1_dev_set = USBH_UC1_DEV_MODE_SEL,
};

static const struct bcm63xx_usbh_phy_variant usbh_bcm6358 = {
	.regs = {
		[USBH_BRT_CONTROL1] = -1,
		[USBH_BRT_CONTROL2] = -1,
		[USBH_BRT_STATUS1] = -1,
		[USBH_BRT_STATUS2] = -1,
		[USBH_UTMI_CONTROL1] = -1,
		[USBH_TEST_PORT_CONTROL] = 0x24,
		[USBH_PLL_CONTROL1] = -1,
		[USBH_SWAP_CONTROL] = 0x00,
		[USBH_GENERIC_CONTROL] = -1,
		[USBH_FRAME_ADJUST_VALUE] = -1,
		[USBH_SETUP] = -1,
		[USBH_MDIO] = -1,
		[USBH_MDIO32] = -1,
		[USBH_USB_SIM_CONTROL] = -1,
	},
	/*
	 * The magic value comes for the original vendor BSP
	 * and is needed for USB to work. Datasheet does not
	 * help, so the magic value is used as-is.
	 */
	.tpc_val = 0x1c0020,
};

static const struct bcm63xx_usbh_phy_variant usbh_bcm6368 = {
	.regs = {
		[USBH_BRT_CONTROL1] = 0x00,
		[USBH_BRT_CONTROL2] = 0x04,
		[USBH_BRT_STATUS1] = 0x08,
		[USBH_BRT_STATUS2] = 0x0c,
		[USBH_UTMI_CONTROL1] = 0x10,
		[USBH_TEST_PORT_CONTROL] = 0x14,
		[USBH_PLL_CONTROL1] = 0x18,
		[USBH_SWAP_CONTROL] = 0x1c,
		[USBH_GENERIC_CONTROL] = -1,
		[USBH_FRAME_ADJUST_VALUE] = 0x24,
		[USBH_SETUP] = 0x28,
		[USBH_MDIO] = 0x2c,
		[USBH_MDIO32] = 0x30,
		[USBH_USB_SIM_CONTROL] = 0x34,
	},
	.power_pllc_clr = USBH_PLLC_PLL_IDDQ_PWRDN | USBH_PLLC_PLL_PWRDN_DELAY,
	.setup_set = USBH_S_IOC,
	.swapctl_dev_set = USBH_SC_USB_DEVICE_SEL,
	.utmictl1_dev_set = USBH_UC1_DEV_MODE_SEL,
};

static const struct bcm63xx_usbh_phy_variant usbh_bcm63268 = {
	.regs = {
		[USBH_BRT_CONTROL1] = 0x00,
		[USBH_BRT_CONTROL2] = 0x04,
		[USBH_BRT_STATUS1] = 0x08,
		[USBH_BRT_STATUS2] = 0x0c,
		[USBH_UTMI_CONTROL1] = 0x10,
		[USBH_TEST_PORT_CONTROL] = 0x14,
		[USBH_PLL_CONTROL1] = 0x18,
		[USBH_SWAP_CONTROL] = 0x1c,
		[USBH_GENERIC_CONTROL] = 0x20,
		[USBH_FRAME_ADJUST_VALUE] = 0x24,
		[USBH_SETUP] = 0x28,
		[USBH_MDIO] = 0x2c,
		[USBH_MDIO32] = 0x30,
		[USBH_USB_SIM_CONTROL] = 0x34,
	},
	.power_pllc_clr = USBH_PLLC_PLL_IDDQ_PWRDN | USBH_PLLC_PLL_PWRDN_DELAY,
	.setup_clr = USBH_S_IPP,
	.setup_set = USBH_S_IOC,
	.swapctl_dev_set = USBH_SC_USB_DEVICE_SEL,
	.utmictl1_dev_set = USBH_UC1_DEV_MODE_SEL,
};

static inline bool usbh_has_reg(struct bcm63xx_usbh_phy *usbh, int reg)
{
	return (usbh->variant->regs[reg] >= 0);
}

static inline u32 usbh_readl(struct bcm63xx_usbh_phy *usbh, int reg)
{
	return __raw_readl(usbh->base + usbh->variant->regs[reg]);
}

static inline void usbh_writel(struct bcm63xx_usbh_phy *usbh, int reg,
			       u32 value)
{
	__raw_writel(value, usbh->base + usbh->variant->regs[reg]);
}

static int bcm63xx_usbh_phy_init(struct phy *phy)
{
	struct bcm63xx_usbh_phy *usbh = phy_get_drvdata(phy);
	int ret;

	ret = clk_prepare_enable(usbh->usbh_clk);
	if (ret) {
		dev_err(&phy->dev, "unable to enable usbh clock: %d\n", ret);
		return ret;
	}

	ret = clk_prepare_enable(usbh->usb_ref_clk);
	if (ret) {
		dev_err(&phy->dev, "unable to enable usb_ref clock: %d\n", ret);
		clk_disable_unprepare(usbh->usbh_clk);
		return ret;
	}

	ret = reset_control_reset(usbh->reset);
	if (ret) {
		dev_err(&phy->dev, "unable to reset device: %d\n", ret);
		clk_disable_unprepare(usbh->usb_ref_clk);
		clk_disable_unprepare(usbh->usbh_clk);
		return ret;
	}

	/* Configure to work in native CPU endian */
	if (usbh_has_reg(usbh, USBH_SWAP_CONTROL)) {
		u32 val = usbh_readl(usbh, USBH_SWAP_CONTROL);

		val |= USBH_SC_EHCI_DATA_SWAP;
		val &= ~USBH_SC_EHCI_ENDIAN_SWAP;

		val |= USBH_SC_OHCI_DATA_SWAP;
		val &= ~USBH_SC_OHCI_ENDIAN_SWAP;

		if (usbh->device_mode && usbh->variant->swapctl_dev_set)
			val |= usbh->variant->swapctl_dev_set;

		usbh_writel(usbh, USBH_SWAP_CONTROL, val);
	}

	if (usbh_has_reg(usbh, USBH_SETUP)) {
		u32 val = usbh_readl(usbh, USBH_SETUP);

		val |= usbh->variant->setup_set;
		val &= ~usbh->variant->setup_clr;

		usbh_writel(usbh, USBH_SETUP, val);
	}

	if (usbh_has_reg(usbh, USBH_USB_SIM_CONTROL)) {
		u32 val = usbh_readl(usbh, USBH_USB_SIM_CONTROL);

		val |= usbh->variant->usc_set;

		usbh_writel(usbh, USBH_USB_SIM_CONTROL, val);
	}

	if (usbh->variant->tpc_val &&
	    usbh_has_reg(usbh, USBH_TEST_PORT_CONTROL))
		usbh_writel(usbh, USBH_TEST_PORT_CONTROL,
			    usbh->variant->tpc_val);

	if (usbh->device_mode &&
	    usbh_has_reg(usbh, USBH_UTMI_CONTROL1) &&
	    usbh->variant->utmictl1_dev_set) {
		u32 val = usbh_readl(usbh, USBH_UTMI_CONTROL1);

		val |= usbh->variant->utmictl1_dev_set;

		usbh_writel(usbh, USBH_UTMI_CONTROL1, val);
	}

	return 0;
}

static int bcm63xx_usbh_phy_power_on(struct phy *phy)
{
	struct bcm63xx_usbh_phy *usbh = phy_get_drvdata(phy);

	if (usbh_has_reg(usbh, USBH_PLL_CONTROL1)) {
		u32 val = usbh_readl(usbh, USBH_PLL_CONTROL1);

		val |= usbh->variant->power_pllc_set;
		val &= ~usbh->variant->power_pllc_clr;

		usbh_writel(usbh, USBH_PLL_CONTROL1, val);
	}

	return 0;
}

static int bcm63xx_usbh_phy_power_off(struct phy *phy)
{
	struct bcm63xx_usbh_phy *usbh = phy_get_drvdata(phy);

	if (usbh_has_reg(usbh, USBH_PLL_CONTROL1)) {
		u32 val = usbh_readl(usbh, USBH_PLL_CONTROL1);

		val &= ~usbh->variant->power_pllc_set;
		val |= usbh->variant->power_pllc_clr;

		usbh_writel(usbh, USBH_PLL_CONTROL1, val);
	}

	return 0;
}

static int bcm63xx_usbh_phy_exit(struct phy *phy)
{
	struct bcm63xx_usbh_phy *usbh = phy_get_drvdata(phy);

	clk_disable_unprepare(usbh->usbh_clk);
	clk_disable_unprepare(usbh->usb_ref_clk);

	return 0;
}

static const struct phy_ops bcm63xx_usbh_phy_ops = {
	.exit = bcm63xx_usbh_phy_exit,
	.init = bcm63xx_usbh_phy_init,
	.power_off = bcm63xx_usbh_phy_power_off,
	.power_on = bcm63xx_usbh_phy_power_on,
	.owner = THIS_MODULE,
};

static struct phy *bcm63xx_usbh_phy_xlate(struct device *dev,
					  const struct of_phandle_args *args)
{
	struct bcm63xx_usbh_phy *usbh = dev_get_drvdata(dev);

	usbh->device_mode = !!args->args[0];

	return of_phy_simple_xlate(dev, args);
}

static int __init bcm63xx_usbh_phy_probe(struct platform_device *pdev)
{
	struct device *dev = &pdev->dev;
	struct bcm63xx_usbh_phy	*usbh;
	const struct bcm63xx_usbh_phy_variant *variant;
	struct phy *phy;
	struct phy_provider *phy_provider;

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

	variant = device_get_match_data(dev);
	if (!variant)
		return -EINVAL;
	usbh->variant = variant;

	usbh->base = devm_platform_ioremap_resource(pdev, 0);
	if (IS_ERR(usbh->base))
		return PTR_ERR(usbh->base);

	usbh->reset = devm_reset_control_get_exclusive(dev, NULL);
	if (IS_ERR(usbh->reset)) {
		if (PTR_ERR(usbh->reset) != -EPROBE_DEFER)
			dev_err(dev, "failed to get reset\n");
		return PTR_ERR(usbh->reset);
	}

	usbh->usbh_clk = devm_clk_get_optional(dev, "usbh");
	if (IS_ERR(usbh->usbh_clk))
		return PTR_ERR(usbh->usbh_clk);

	usbh->usb_ref_clk = devm_clk_get_optional(dev, "usb_ref");
	if (IS_ERR(usbh->usb_ref_clk))
		return PTR_ERR(usbh->usb_ref_clk);

	phy = devm_phy_create(dev, NULL, &bcm63xx_usbh_phy_ops);
	if (IS_ERR(phy)) {
		dev_err(dev, "failed to create PHY\n");
		return PTR_ERR(phy);
	}

	platform_set_drvdata(pdev, usbh);
	phy_set_drvdata(phy, usbh);

	phy_provider = devm_of_phy_provider_register(dev,
						     bcm63xx_usbh_phy_xlate);
	if (IS_ERR(phy_provider)) {
		dev_err(dev, "failed to register PHY provider\n");
		return PTR_ERR(phy_provider);
	}

	dev_dbg(dev, "Registered BCM63xx USB PHY driver\n");

	return 0;
}

static const struct of_device_id bcm63xx_usbh_phy_ids[] __initconst = {
	{ .compatible = "brcm,bcm6318-usbh-phy", .data = &usbh_bcm6318 },
	{ .compatible = "brcm,bcm6328-usbh-phy", .data = &usbh_bcm6328 },
	{ .compatible = "brcm,bcm6358-usbh-phy", .data = &usbh_bcm6358 },
	{ .compatible = "brcm,bcm6362-usbh-phy", .data = &usbh_bcm6368 },
	{ .compatible = "brcm,bcm6368-usbh-phy", .data = &usbh_bcm6368 },
	{ .compatible = "brcm,bcm63268-usbh-phy", .data = &usbh_bcm63268 },
	{ /* sentinel */ }
};
MODULE_DEVICE_TABLE(of, bcm63xx_usbh_phy_ids);

static struct platform_driver bcm63xx_usbh_phy_driver __refdata = {
	.driver	= {
		.name = "bcm63xx-usbh-phy",
		.of_match_table = bcm63xx_usbh_phy_ids,
	},
	.probe	= bcm63xx_usbh_phy_probe,
};
module_platform_driver(bcm63xx_usbh_phy_driver);

MODULE_DESCRIPTION("BCM63xx USBH PHY driver");
MODULE_AUTHOR("Álvaro Fernández Rojas <noltari@gmail.com>");
MODULE_AUTHOR("Simon Arlott");
MODULE_LICENSE("GPL");