// SPDX-License-Identifier: GPL-2.0
/*
 * PMC MSP EHCI (Host Controller Driver) for USB.
 *
 * (C) Copyright 2006-2010 PMC-Sierra Inc
 */

/* includes */
#include <linux/platform_device.h>
#include <linux/gpio.h>
#include <linux/usb.h>
#include <msp_usb.h>

/* stream disable*/
#define USB_CTRL_MODE_STREAM_DISABLE    0x10

/* threshold */
#define USB_CTRL_FIFO_THRESH            0x00300000

/* register offset for usb_mode */
#define USB_EHCI_REG_USB_MODE           0x68

/* register offset for usb fifo */
#define USB_EHCI_REG_USB_FIFO           0x24

/* register offset for usb status */
#define USB_EHCI_REG_USB_STATUS         0x44

/* serial/parallel transceiver */
#define USB_EHCI_REG_BIT_STAT_STS       (1<<29)

/* TWI USB0 host device pin */
#define MSP_PIN_USB0_HOST_DEV           49

/* TWI USB1 host device pin */
#define MSP_PIN_USB1_HOST_DEV           50


static void usb_hcd_tdi_set_mode(struct ehci_hcd *ehci)
{
        u8 *base;
        u8 *statreg;
        u8 *fiforeg;
        u32 val;
        struct ehci_regs *reg_base = ehci->regs;

        /* get register base */
        base = (u8 *)reg_base + USB_EHCI_REG_USB_MODE;
        statreg = (u8 *)reg_base + USB_EHCI_REG_USB_STATUS;
        fiforeg = (u8 *)reg_base + USB_EHCI_REG_USB_FIFO;

        /* Disable controller mode stream */
        val = ehci_readl(ehci, (u32 *)base);
        ehci_writel(ehci, (val | USB_CTRL_MODE_STREAM_DISABLE),
                        (u32 *)base);

        /* clear STS to select parallel transceiver interface */
        val = ehci_readl(ehci, (u32 *)statreg);
        val = val & ~USB_EHCI_REG_BIT_STAT_STS;
        ehci_writel(ehci, val, (u32 *)statreg);

        /* write to set the proper fifo threshold */
        ehci_writel(ehci, USB_CTRL_FIFO_THRESH, (u32 *)fiforeg);

        /* set TWI GPIO USB_HOST_DEV pin high */
        gpio_direction_output(MSP_PIN_USB0_HOST_DEV, 1);
}

/* called during probe() after chip reset completes */
static int ehci_msp_setup(struct usb_hcd *hcd)
{
        struct ehci_hcd         *ehci = hcd_to_ehci(hcd);
        int                     retval;

        ehci->big_endian_mmio = 1;
        ehci->big_endian_desc = 1;

        ehci->caps = hcd->regs;
        hcd->has_tt = 1;

        retval = ehci_setup(hcd);
        if (retval)
                return retval;

        usb_hcd_tdi_set_mode(ehci);

        return retval;
}


/* configure so an HC device and id are always provided
 * always called with process context; sleeping is OK
 */

static int usb_hcd_msp_map_regs(struct mspusb_device *dev)
{
        struct resource *res;
        struct platform_device *pdev = &dev->dev;
        u32 res_len;
        int retval;

        /* MAB register space */
        res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
        if (res == NULL)
                return -ENOMEM;
        res_len = resource_size(res);
        if (!request_mem_region(res->start, res_len, "mab regs"))
                return -EBUSY;

        dev->mab_regs = ioremap(res->start, res_len);
        if (dev->mab_regs == NULL) {
                retval = -ENOMEM;
                goto err1;
        }

        /* MSP USB register space */
        res = platform_get_resource(pdev, IORESOURCE_MEM, 2);
        if (res == NULL) {
                retval = -ENOMEM;
                goto err2;
        }
        res_len = resource_size(res);
        if (!request_mem_region(res->start, res_len, "usbid regs")) {
                retval = -EBUSY;
                goto err2;
        }
        dev->usbid_regs = ioremap(res->start, res_len);
        if (dev->usbid_regs == NULL) {
                retval = -ENOMEM;
                goto err3;
        }

        return 0;
err3:
        res = platform_get_resource(pdev, IORESOURCE_MEM, 2);
        res_len = resource_size(res);
        release_mem_region(res->start, res_len);
err2:
        iounmap(dev->mab_regs);
err1:
        res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
        res_len = resource_size(res);
        release_mem_region(res->start, res_len);
        dev_err(&pdev->dev, "Failed to map non-EHCI regs.\n");
        return retval;
}

/**
 * usb_hcd_msp_probe - initialize PMC MSP-based HCDs
 * Context: !in_interrupt()
 *
 * Allocates basic resources for this USB host controller, and
 * then invokes the start() method for the HCD associated with it
 * through the hotplug entry's driver_data.
 *
 */
int usb_hcd_msp_probe(const struct hc_driver *driver,
                          struct platform_device *dev)
{
        int retval;
        struct usb_hcd *hcd;
        struct resource *res;
        struct ehci_hcd         *ehci ;

        hcd = usb_create_hcd(driver, &dev->dev, "pmcmsp");
        if (!hcd)
                return -ENOMEM;

        res = platform_get_resource(dev, IORESOURCE_MEM, 0);
        if (res == NULL) {
                pr_debug("No IOMEM resource info for %s.\n", dev->name);
                retval = -ENOMEM;
                goto err1;
        }
        hcd->rsrc_start = res->start;
        hcd->rsrc_len = resource_size(res);
        if (!request_mem_region(hcd->rsrc_start, hcd->rsrc_len, dev->name)) {
                retval = -EBUSY;
                goto err1;
        }
        hcd->regs = ioremap(hcd->rsrc_start, hcd->rsrc_len);
        if (!hcd->regs) {
                pr_debug("ioremap failed");
                retval = -ENOMEM;
                goto err2;
        }

        res = platform_get_resource(dev, IORESOURCE_IRQ, 0);
        if (res == NULL) {
                dev_err(&dev->dev, "No IRQ resource info for %s.\n", dev->name);
                retval = -ENOMEM;
                goto err3;
        }

        /* Map non-EHCI register spaces */
        retval = usb_hcd_msp_map_regs(to_mspusb_device(dev));
        if (retval != 0)
                goto err3;

        ehci = hcd_to_ehci(hcd);
        ehci->big_endian_mmio = 1;
        ehci->big_endian_desc = 1;


        retval = usb_add_hcd(hcd, res->start, IRQF_SHARED);
        if (retval == 0) {
                device_wakeup_enable(hcd->self.controller);
                return 0;
        }

        usb_remove_hcd(hcd);
err3:
        iounmap(hcd->regs);
err2:
        release_mem_region(hcd->rsrc_start, hcd->rsrc_len);
err1:
        usb_put_hcd(hcd);

        return retval;
}



/**
 * usb_hcd_msp_remove - shutdown processing for PMC MSP-based HCDs
 * @dev: USB Host Controller being removed
 * Context: !in_interrupt()
 *
 * Reverses the effect of usb_hcd_msp_probe(), first invoking
 * the HCD's stop() method.  It is always called from a thread
 * context, normally "rmmod", "apmd", or something similar.
 *
 * may be called without controller electrically present
 * may be called with controller, bus, and devices active
 */
void usb_hcd_msp_remove(struct usb_hcd *hcd, struct platform_device *dev)
{
        usb_remove_hcd(hcd);
        iounmap(hcd->regs);
        release_mem_region(hcd->rsrc_start, hcd->rsrc_len);
        usb_put_hcd(hcd);
}

static const struct hc_driver ehci_msp_hc_driver = {
        .description =          hcd_name,
        .product_desc =         "PMC MSP EHCI",
        .hcd_priv_size =        sizeof(struct ehci_hcd),

        /*
         * generic hardware linkage
         */
        .irq =                  ehci_irq,
        .flags =                HCD_MEMORY | HCD_DMA | HCD_USB2 | HCD_BH,

        /*
         * basic lifecycle operations
         */
        .reset                  = ehci_msp_setup,
        .shutdown               = ehci_shutdown,
        .start                  = ehci_run,
        .stop                   = ehci_stop,

        /*
         * managing i/o requests and associated device resources
         */
        .urb_enqueue            = ehci_urb_enqueue,
        .urb_dequeue            = ehci_urb_dequeue,
        .endpoint_disable       = ehci_endpoint_disable,
        .endpoint_reset         = ehci_endpoint_reset,

        /*
         * scheduling support
         */
        .get_frame_number       = ehci_get_frame,

        /*
         * root hub support
         */
        .hub_status_data        = ehci_hub_status_data,
        .hub_control            = ehci_hub_control,
        .bus_suspend            = ehci_bus_suspend,
        .bus_resume             = ehci_bus_resume,
        .relinquish_port        = ehci_relinquish_port,
        .port_handed_over       = ehci_port_handed_over,

        .clear_tt_buffer_complete       = ehci_clear_tt_buffer_complete,
};

static int ehci_hcd_msp_drv_probe(struct platform_device *pdev)
{
        int ret;

        pr_debug("In ehci_hcd_msp_drv_probe");

        if (usb_disabled())
                return -ENODEV;

        gpio_request(MSP_PIN_USB0_HOST_DEV, "USB0_HOST_DEV_GPIO");

        ret = usb_hcd_msp_probe(&ehci_msp_hc_driver, pdev);

        return ret;
}

static int ehci_hcd_msp_drv_remove(struct platform_device *pdev)
{
        struct usb_hcd *hcd = platform_get_drvdata(pdev);

        usb_hcd_msp_remove(hcd, pdev);

        /* free TWI GPIO USB_HOST_DEV pin */
        gpio_free(MSP_PIN_USB0_HOST_DEV);

        return 0;
}

MODULE_ALIAS("pmcmsp-ehci");

static struct platform_driver ehci_hcd_msp_driver = {
        .probe          = ehci_hcd_msp_drv_probe,
        .remove         = ehci_hcd_msp_drv_remove,
        .driver         = {
                .name   = "pmcmsp-ehci",
        },
};