// SPDX-License-Identifier: GPL-2.0+
/*
 * Driver for Aeroflex Gaisler GRLIB GRUSBHC EHCI host controller
 *
 * GRUSBHC is typically found on LEON/GRLIB SoCs
 *
 * (c) Jan Andersson <jan@gaisler.com>
 *
 * Based on ehci-ppc-of.c which is:
 * (c) Valentine Barshak <vbarshak@ru.mvista.com>
 * and in turn based on "ehci-ppc-soc.c" by Stefan Roese <sr@denx.de>
 * and "ohci-ppc-of.c" by Sylvain Munaut <tnt@246tNt.com>
 */

#include <linux/err.h>
#include <linux/signal.h>

#include <linux/of_irq.h>
#include <linux/of_address.h>
#include <linux/of_platform.h>

#define GRUSBHC_HCIVERSION 0x0100 /* Known value of cap. reg. HCIVERSION */

static const struct hc_driver ehci_grlib_hc_driver = {
        .description            = hcd_name,
        .product_desc           = "GRLIB GRUSBHC 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_setup,
        .start                  = ehci_run,
        .stop                   = ehci_stop,
        .shutdown               = ehci_shutdown,

        /*
         * 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,
#ifdef  CONFIG_PM
        .bus_suspend            = ehci_bus_suspend,
        .bus_resume             = ehci_bus_resume,
#endif
        .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_grlib_probe(struct platform_device *op)
{
        struct device_node *dn = op->dev.of_node;
        struct usb_hcd *hcd;
        struct ehci_hcd *ehci = NULL;
        struct resource res;
        u32 hc_capbase;
        int irq;
        int rv;

        if (usb_disabled())
                return -ENODEV;

        dev_dbg(&op->dev, "initializing GRUSBHC EHCI USB Controller\n");

        rv = of_address_to_resource(dn, 0, &res);
        if (rv)
                return rv;

        /* usb_create_hcd requires dma_mask != NULL */
        op->dev.dma_mask = &op->dev.coherent_dma_mask;
        hcd = usb_create_hcd(&ehci_grlib_hc_driver, &op->dev,
                        "GRUSBHC EHCI USB");
        if (!hcd)
                return -ENOMEM;

        hcd->rsrc_start = res.start;
        hcd->rsrc_len = resource_size(&res);

        irq = irq_of_parse_and_map(dn, 0);
        if (!irq) {
                dev_err(&op->dev, "%s: irq_of_parse_and_map failed\n",
                        __FILE__);
                rv = -EBUSY;
                goto err_irq;
        }

        hcd->regs = devm_ioremap_resource(&op->dev, &res);
        if (IS_ERR(hcd->regs)) {
                rv = PTR_ERR(hcd->regs);
                goto err_ioremap;
        }

        ehci = hcd_to_ehci(hcd);

        ehci->caps = hcd->regs;

        /* determine endianness of this implementation */
        hc_capbase = ehci_readl(ehci, &ehci->caps->hc_capbase);
        if (HC_VERSION(ehci, hc_capbase) != GRUSBHC_HCIVERSION) {
                ehci->big_endian_mmio = 1;
                ehci->big_endian_desc = 1;
                ehci->big_endian_capbase = 1;
        }

        rv = usb_add_hcd(hcd, irq, 0);
        if (rv)
                goto err_ioremap;

        device_wakeup_enable(hcd->self.controller);
        return 0;

err_ioremap:
        irq_dispose_mapping(irq);
err_irq:
        usb_put_hcd(hcd);

        return rv;
}


static void ehci_hcd_grlib_remove(struct platform_device *op)
{
        struct usb_hcd *hcd = platform_get_drvdata(op);

        dev_dbg(&op->dev, "stopping GRLIB GRUSBHC EHCI USB Controller\n");

        usb_remove_hcd(hcd);

        irq_dispose_mapping(hcd->irq);

        usb_put_hcd(hcd);
}


static const struct of_device_id ehci_hcd_grlib_of_match[] = {
        {
                .name = "GAISLER_EHCI",
         },
        {
                .name = "01_026",
         },
        {},
};
MODULE_DEVICE_TABLE(of, ehci_hcd_grlib_of_match);


static struct platform_driver ehci_grlib_driver = {
        .probe          = ehci_hcd_grlib_probe,
        .remove         = ehci_hcd_grlib_remove,
        .shutdown       = usb_hcd_platform_shutdown,
        .driver = {
                .name = "grlib-ehci",
                .of_match_table = ehci_hcd_grlib_of_match,
        },
};