/*
 * Broadcom specific Advanced Microcontroller Bus
 * Broadcom USB-core driver (BCMA bus glue)
 *
 * Copyright 2011-2015 Hauke Mehrtens <hauke@hauke-m.de>
 * Copyright 2015 Felix Fietkau <nbd@openwrt.org>
 *
 * Based on ssb-ohci driver
 * Copyright 2007 Michael Buesch <m@bues.ch>
 *
 * Derived from the OHCI-PCI driver
 * Copyright 1999 Roman Weissgaerber
 * Copyright 2000-2002 David Brownell
 * Copyright 1999 Linus Torvalds
 * Copyright 1999 Gregory P. Smith
 *
 * Derived from the USBcore related parts of Broadcom-SB
 * Copyright 2005-2011 Broadcom Corporation
 *
 * Licensed under the GNU/GPL. See COPYING for details.
 */
#include <linux/bcma/bcma.h>
#include <linux/delay.h>
#include <linux/gpio/consumer.h>
#include <linux/platform_device.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/of.h>
#include <linux/of_gpio.h>
#include <linux/of_platform.h>
#include <linux/usb/ehci_pdriver.h>
#include <linux/usb/ohci_pdriver.h>

MODULE_AUTHOR("Hauke Mehrtens");
MODULE_DESCRIPTION("Common USB driver for BCMA Bus");
MODULE_LICENSE("GPL");

/* See BCMA_CLKCTLST_EXTRESREQ and BCMA_CLKCTLST_EXTRESST */
#define USB_BCMA_CLKCTLST_USB_CLK_REQ			0x00000100

struct bcma_hcd_device {
	struct bcma_device *core;
	struct platform_device *ehci_dev;
	struct platform_device *ohci_dev;
	struct gpio_desc *gpio_desc;
};

/* Wait for bitmask in a register to get set or cleared.
 * timeout is in units of ten-microseconds.
 */
static int bcma_wait_bits(struct bcma_device *dev, u16 reg, u32 bitmask,
			  int timeout)
{
	int i;
	u32 val;

	for (i = 0; i < timeout; i++) {
		val = bcma_read32(dev, reg);
		if ((val & bitmask) == bitmask)
			return 0;
		udelay(10);
	}

	return -ETIMEDOUT;
}

static void bcma_hcd_4716wa(struct bcma_device *dev)
{
#ifdef CONFIG_BCMA_DRIVER_MIPS
	/* Work around for 4716 failures. */
	if (dev->bus->chipinfo.id == 0x4716) {
		u32 tmp;

		tmp = bcma_cpu_clock(&dev->bus->drv_mips);
		if (tmp >= 480000000)
			tmp = 0x1846b; /* set CDR to 0x11(fast) */
		else if (tmp == 453000000)
			tmp = 0x1046b; /* set CDR to 0x10(slow) */
		else
			tmp = 0;

		/* Change Shim mdio control reg to fix host not acking at
		 * high frequencies
		 */
		if (tmp) {
			bcma_write32(dev, 0x524, 0x1); /* write sel to enable */
			udelay(500);

			bcma_write32(dev, 0x524, tmp);
			udelay(500);
			bcma_write32(dev, 0x524, 0x4ab);
			udelay(500);
			bcma_read32(dev, 0x528);
			bcma_write32(dev, 0x528, 0x80000000);
		}
	}
#endif /* CONFIG_BCMA_DRIVER_MIPS */
}

/* based on arch/mips/brcm-boards/bcm947xx/pcibios.c */
static void bcma_hcd_init_chip_mips(struct bcma_device *dev)
{
	u32 tmp;

	/*
	 * USB 2.0 special considerations:
	 *
	 * 1. Since the core supports both OHCI and EHCI functions, it must
	 *    only be reset once.
	 *
	 * 2. In addition to the standard SI reset sequence, the Host Control
	 *    Register must be programmed to bring the USB core and various
	 *    phy components out of reset.
	 */
	if (!bcma_core_is_enabled(dev)) {
		bcma_core_enable(dev, 0);
		mdelay(10);
		if (dev->id.rev >= 5) {
			/* Enable Misc PLL */
			tmp = bcma_read32(dev, 0x1e0);
			tmp |= 0x100;
			bcma_write32(dev, 0x1e0, tmp);
			if (bcma_wait_bits(dev, 0x1e0, 1 << 24, 100))
				printk(KERN_EMERG "Failed to enable misc PPL!\n");

			/* Take out of resets */
			bcma_write32(dev, 0x200, 0x4ff);
			udelay(25);
			bcma_write32(dev, 0x200, 0x6ff);
			udelay(25);

			/* Make sure digital and AFE are locked in USB PHY */
			bcma_write32(dev, 0x524, 0x6b);
			udelay(50);
			tmp = bcma_read32(dev, 0x524);
			udelay(50);
			bcma_write32(dev, 0x524, 0xab);
			udelay(50);
			tmp = bcma_read32(dev, 0x524);
			udelay(50);
			bcma_write32(dev, 0x524, 0x2b);
			udelay(50);
			tmp = bcma_read32(dev, 0x524);
			udelay(50);
			bcma_write32(dev, 0x524, 0x10ab);
			udelay(50);
			tmp = bcma_read32(dev, 0x524);

			if (bcma_wait_bits(dev, 0x528, 0xc000, 10000)) {
				tmp = bcma_read32(dev, 0x528);
				printk(KERN_EMERG
				       "USB20H mdio_rddata 0x%08x\n", tmp);
			}
			bcma_write32(dev, 0x528, 0x80000000);
			tmp = bcma_read32(dev, 0x314);
			udelay(265);
			bcma_write32(dev, 0x200, 0x7ff);
			udelay(10);

			/* Take USB and HSIC out of non-driving modes */
			bcma_write32(dev, 0x510, 0);
		} else {
			bcma_write32(dev, 0x200, 0x7ff);

			udelay(1);
		}

		bcma_hcd_4716wa(dev);
	}
}

/**
 * bcma_hcd_usb20_old_arm_init - Initialize old USB 2.0 controller on ARM
 *
 * Old USB 2.0 core is identified as BCMA_CORE_USB20_HOST and was introduced
 * long before Northstar devices. It seems some cheaper chipsets like BCM53573
 * still use it.
 * Initialization of this old core differs between MIPS and ARM.
 */
static int bcma_hcd_usb20_old_arm_init(struct bcma_hcd_device *usb_dev)
{
	struct bcma_device *core = usb_dev->core;
	struct device *dev = &core->dev;
	struct bcma_device *pmu_core;

	usleep_range(10000, 20000);
	if (core->id.rev < 5)
		return 0;

	pmu_core = bcma_find_core(core->bus, BCMA_CORE_PMU);
	if (!pmu_core) {
		dev_err(dev, "Could not find PMU core\n");
		return -ENOENT;
	}

	/* Take USB core out of reset */
	bcma_awrite32(core, BCMA_IOCTL, BCMA_IOCTL_CLK | BCMA_IOCTL_FGC);
	usleep_range(100, 200);
	bcma_awrite32(core, BCMA_RESET_CTL, BCMA_RESET_CTL_RESET);
	usleep_range(100, 200);
	bcma_awrite32(core, BCMA_RESET_CTL, 0);
	usleep_range(100, 200);
	bcma_awrite32(core, BCMA_IOCTL, BCMA_IOCTL_CLK);
	usleep_range(100, 200);

	/* Enable Misc PLL */
	bcma_write32(core, BCMA_CLKCTLST, BCMA_CLKCTLST_FORCEHT |
					  BCMA_CLKCTLST_HQCLKREQ |
					  USB_BCMA_CLKCTLST_USB_CLK_REQ);
	usleep_range(100, 200);

	bcma_write32(core, 0x510, 0xc7f85000);
	bcma_write32(core, 0x510, 0xc7f85003);
	usleep_range(300, 600);

	/* Program USB PHY PLL parameters */
	bcma_write32(pmu_core, BCMA_CC_PMU_PLLCTL_ADDR, 0x6);
	bcma_write32(pmu_core, BCMA_CC_PMU_PLLCTL_DATA, 0x005360c1);
	usleep_range(100, 200);
	bcma_write32(pmu_core, BCMA_CC_PMU_PLLCTL_ADDR, 0x7);
	bcma_write32(pmu_core, BCMA_CC_PMU_PLLCTL_DATA, 0x0);
	usleep_range(100, 200);
	bcma_set32(pmu_core, BCMA_CC_PMU_CTL, BCMA_CC_PMU_CTL_PLL_UPD);
	usleep_range(100, 200);

	bcma_write32(core, 0x510, 0x7f8d007);
	udelay(1000);

	/* Take controller out of reset */
	bcma_write32(core, 0x200, 0x4ff);
	usleep_range(25, 50);
	bcma_write32(core, 0x200, 0x6ff);
	usleep_range(25, 50);
	bcma_write32(core, 0x200, 0x7ff);
	usleep_range(25, 50);

	of_platform_default_populate(dev->of_node, NULL, dev);

	return 0;
}

static void bcma_hcd_usb20_ns_init_hc(struct bcma_device *dev)
{
	u32 val;

	/* Set packet buffer OUT threshold */
	val = bcma_read32(dev, 0x94);
	val &= 0xffff;
	val |= 0x80 << 16;
	bcma_write32(dev, 0x94, val);

	/* Enable break memory transfer */
	val = bcma_read32(dev, 0x9c);
	val |= 1;
	bcma_write32(dev, 0x9c, val);

	/*
	 * Broadcom initializes PHY and then waits to ensure HC is ready to be
	 * configured. In our case the order is reversed. We just initialized
	 * controller and we let HCD initialize PHY, so let's wait (sleep) now.
	 */
	usleep_range(1000, 2000);
}

/**
 * bcma_hcd_usb20_ns_init - Initialize Northstar USB 2.0 controller
 */
static int bcma_hcd_usb20_ns_init(struct bcma_hcd_device *bcma_hcd)
{
	struct bcma_device *core = bcma_hcd->core;
	struct bcma_chipinfo *ci = &core->bus->chipinfo;
	struct device *dev = &core->dev;

	bcma_core_enable(core, 0);

	if (ci->id == BCMA_CHIP_ID_BCM4707 ||
	    ci->id == BCMA_CHIP_ID_BCM53018)
		bcma_hcd_usb20_ns_init_hc(core);

	of_platform_default_populate(dev->of_node, NULL, dev);

	return 0;
}

static void bcma_hci_platform_power_gpio(struct bcma_device *dev, bool val)
{
	struct bcma_hcd_device *usb_dev = bcma_get_drvdata(dev);

	if (IS_ERR_OR_NULL(usb_dev->gpio_desc))
		return;

	gpiod_set_value(usb_dev->gpio_desc, val);
}

static const struct usb_ehci_pdata ehci_pdata = {
};

static const struct usb_ohci_pdata ohci_pdata = {
};

static struct platform_device *bcma_hcd_create_pdev(struct bcma_device *dev,
						    const char *name, u32 addr,
						    const void *data,
						    size_t size)
{
	struct platform_device *hci_dev;
	struct resource hci_res[2];
	int ret;

	memset(hci_res, 0, sizeof(hci_res));

	hci_res[0].start = addr;
	hci_res[0].end = hci_res[0].start + 0x1000 - 1;
	hci_res[0].flags = IORESOURCE_MEM;

	hci_res[1].start = dev->irq;
	hci_res[1].flags = IORESOURCE_IRQ;

	hci_dev = platform_device_alloc(name, 0);
	if (!hci_dev)
		return ERR_PTR(-ENOMEM);

	hci_dev->dev.parent = &dev->dev;
	hci_dev->dev.dma_mask = &hci_dev->dev.coherent_dma_mask;

	ret = platform_device_add_resources(hci_dev, hci_res,
					    ARRAY_SIZE(hci_res));
	if (ret)
		goto err_alloc;
	if (data)
		ret = platform_device_add_data(hci_dev, data, size);
	if (ret)
		goto err_alloc;
	ret = platform_device_add(hci_dev);
	if (ret)
		goto err_alloc;

	return hci_dev;

err_alloc:
	platform_device_put(hci_dev);
	return ERR_PTR(ret);
}

static int bcma_hcd_usb20_init(struct bcma_hcd_device *usb_dev)
{
	struct bcma_device *dev = usb_dev->core;
	struct bcma_chipinfo *chipinfo = &dev->bus->chipinfo;
	u32 ohci_addr;
	int err;

	if (dma_set_mask_and_coherent(dev->dma_dev, DMA_BIT_MASK(32)))
		return -EOPNOTSUPP;

	bcma_hcd_init_chip_mips(dev);

	/* In AI chips EHCI is addrspace 0, OHCI is 1 */
	ohci_addr = dev->addr_s[0];
	if ((chipinfo->id == BCMA_CHIP_ID_BCM5357 ||
	     chipinfo->id == BCMA_CHIP_ID_BCM4749)
	    && chipinfo->rev == 0)
		ohci_addr = 0x18009000;

	usb_dev->ohci_dev = bcma_hcd_create_pdev(dev, "ohci-platform",
						 ohci_addr, &ohci_pdata,
						 sizeof(ohci_pdata));
	if (IS_ERR(usb_dev->ohci_dev))
		return PTR_ERR(usb_dev->ohci_dev);

	usb_dev->ehci_dev = bcma_hcd_create_pdev(dev, "ehci-platform",
						 dev->addr, &ehci_pdata,
						 sizeof(ehci_pdata));
	if (IS_ERR(usb_dev->ehci_dev)) {
		err = PTR_ERR(usb_dev->ehci_dev);
		goto err_unregister_ohci_dev;
	}

	return 0;

err_unregister_ohci_dev:
	platform_device_unregister(usb_dev->ohci_dev);
	return err;
}

static int bcma_hcd_usb30_init(struct bcma_hcd_device *bcma_hcd)
{
	struct bcma_device *core = bcma_hcd->core;
	struct device *dev = &core->dev;

	bcma_core_enable(core, 0);

	of_platform_default_populate(dev->of_node, NULL, dev);

	return 0;
}

static int bcma_hcd_probe(struct bcma_device *core)
{
	int err;
	struct bcma_hcd_device *usb_dev;

	/* TODO: Probably need checks here; is the core connected? */

	usb_dev = devm_kzalloc(&core->dev, sizeof(struct bcma_hcd_device),
			       GFP_KERNEL);
	if (!usb_dev)
		return -ENOMEM;
	usb_dev->core = core;

	if (core->dev.of_node)
		usb_dev->gpio_desc = devm_gpiod_get(&core->dev, "vcc",
						    GPIOD_OUT_HIGH);

	switch (core->id.id) {
	case BCMA_CORE_USB20_HOST:
		if (IS_ENABLED(CONFIG_ARM))
			err = bcma_hcd_usb20_old_arm_init(usb_dev);
		else if (IS_ENABLED(CONFIG_MIPS))
			err = bcma_hcd_usb20_init(usb_dev);
		else
			err = -ENOTSUPP;
		break;
	case BCMA_CORE_NS_USB20:
		err = bcma_hcd_usb20_ns_init(usb_dev);
		break;
	case BCMA_CORE_NS_USB30:
		err = bcma_hcd_usb30_init(usb_dev);
		break;
	default:
		return -ENODEV;
	}
	if (err)
		return err;

	bcma_set_drvdata(core, usb_dev);
	return 0;
}

static void bcma_hcd_remove(struct bcma_device *dev)
{
	struct bcma_hcd_device *usb_dev = bcma_get_drvdata(dev);
	struct platform_device *ohci_dev = usb_dev->ohci_dev;
	struct platform_device *ehci_dev = usb_dev->ehci_dev;

	if (ohci_dev)
		platform_device_unregister(ohci_dev);
	if (ehci_dev)
		platform_device_unregister(ehci_dev);

	bcma_core_disable(dev, 0);
}

static void bcma_hcd_shutdown(struct bcma_device *dev)
{
	bcma_hci_platform_power_gpio(dev, false);
	bcma_core_disable(dev, 0);
}

#ifdef CONFIG_PM

static int bcma_hcd_suspend(struct bcma_device *dev)
{
	bcma_hci_platform_power_gpio(dev, false);
	bcma_core_disable(dev, 0);

	return 0;
}

static int bcma_hcd_resume(struct bcma_device *dev)
{
	bcma_hci_platform_power_gpio(dev, true);
	bcma_core_enable(dev, 0);

	return 0;
}

#else /* !CONFIG_PM */
#define bcma_hcd_suspend	NULL
#define bcma_hcd_resume	NULL
#endif /* CONFIG_PM */

static const struct bcma_device_id bcma_hcd_table[] = {
	BCMA_CORE(BCMA_MANUF_BCM, BCMA_CORE_USB20_HOST, BCMA_ANY_REV, BCMA_ANY_CLASS),
	BCMA_CORE(BCMA_MANUF_BCM, BCMA_CORE_NS_USB20, BCMA_ANY_REV, BCMA_ANY_CLASS),
	BCMA_CORE(BCMA_MANUF_BCM, BCMA_CORE_NS_USB30, BCMA_ANY_REV, BCMA_ANY_CLASS),
	{},
};
MODULE_DEVICE_TABLE(bcma, bcma_hcd_table);

static struct bcma_driver bcma_hcd_driver = {
	.name		= KBUILD_MODNAME,
	.id_table	= bcma_hcd_table,
	.probe		= bcma_hcd_probe,
	.remove		= bcma_hcd_remove,
	.shutdown	= bcma_hcd_shutdown,
	.suspend	= bcma_hcd_suspend,
	.resume		= bcma_hcd_resume,
};

static int __init bcma_hcd_init(void)
{
	return bcma_driver_register(&bcma_hcd_driver);
}
module_init(bcma_hcd_init);

static void __exit bcma_hcd_exit(void)
{
	bcma_driver_unregister(&bcma_hcd_driver);
}
module_exit(bcma_hcd_exit);