// SPDX-License-Identifier: GPL-2.0
/*
 * Generic UHCI HCD (Host Controller Driver) for Platform Devices
 *
 * Copyright (c) 2011 Tony Prisk <linux@prisktech.co.nz>
 *
 * This file is based on uhci-grlib.c
 * (C) Copyright 2004-2007 Alan Stern, stern@rowland.harvard.edu
 */

#include <linux/of.h>
#include <linux/device.h>
#include <linux/platform_device.h>
#include <linux/reset.h>

static int uhci_platform_init(struct usb_hcd *hcd)
{
        struct uhci_hcd *uhci = hcd_to_uhci(hcd);

        /* Probe number of ports if not already provided by DT */
        if (!uhci->rh_numports)
                uhci->rh_numports = uhci_count_ports(hcd);

        /* Set up pointers to to generic functions */
        uhci->reset_hc = uhci_generic_reset_hc;
        uhci->check_and_reset_hc = uhci_generic_check_and_reset_hc;

        /* No special actions need to be taken for the functions below */
        uhci->configure_hc = NULL;
        uhci->resume_detect_interrupts_are_broken = NULL;
        uhci->global_suspend_mode_is_broken = NULL;

        /* Reset if the controller isn't already safely quiescent. */
        check_and_reset_hc(uhci);
        return 0;
}

static const struct hc_driver uhci_platform_hc_driver = {
        .description =          hcd_name,
        .product_desc =         "Generic UHCI Host Controller",
        .hcd_priv_size =        sizeof(struct uhci_hcd),

        /* Generic hardware linkage */
        .irq =                  uhci_irq,
        .flags =                HCD_MEMORY | HCD_DMA | HCD_USB11,

        /* Basic lifecycle operations */
        .reset =                uhci_platform_init,
        .start =                uhci_start,
#ifdef CONFIG_PM
        .pci_suspend =          NULL,
        .pci_resume =           NULL,
        .bus_suspend =          uhci_rh_suspend,
        .bus_resume =           uhci_rh_resume,
#endif
        .stop =                 uhci_stop,

        .urb_enqueue =          uhci_urb_enqueue,
        .urb_dequeue =          uhci_urb_dequeue,

        .endpoint_disable =     uhci_hcd_endpoint_disable,
        .get_frame_number =     uhci_hcd_get_frame_number,

        .hub_status_data =      uhci_hub_status_data,
        .hub_control =          uhci_hub_control,
};

static int uhci_hcd_platform_probe(struct platform_device *pdev)
{
        struct device_node *np = pdev->dev.of_node;
        bool dma_mask_64 = false;
        struct usb_hcd *hcd;
        struct uhci_hcd *uhci;
        struct resource *res;
        int ret;

        if (usb_disabled())
                return -ENODEV;

        /*
         * Right now device-tree probed devices don't get dma_mask set.
         * Since shared usb code relies on it, set it here for now.
         * Once we have dma capability bindings this can go away.
         */
        if (of_device_get_match_data(&pdev->dev))
                dma_mask_64 = true;

        ret = dma_coerce_mask_and_coherent(&pdev->dev,
                dma_mask_64 ? DMA_BIT_MASK(64) : DMA_BIT_MASK(32));
        if (ret)
                return ret;

        hcd = usb_create_hcd(&uhci_platform_hc_driver, &pdev->dev,
                        pdev->name);
        if (!hcd)
                return -ENOMEM;

        uhci = hcd_to_uhci(hcd);

        hcd->regs = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
        if (IS_ERR(hcd->regs)) {
                ret = PTR_ERR(hcd->regs);
                goto err_rmr;
        }
        hcd->rsrc_start = res->start;
        hcd->rsrc_len = resource_size(res);

        uhci->regs = hcd->regs;

        /* Grab some things from the device-tree */
        if (np) {
                u32 num_ports;

                if (of_property_read_u32(np, "#ports", &num_ports) == 0) {
                        uhci->rh_numports = num_ports;
                        dev_info(&pdev->dev,
                                "Detected %d ports from device-tree\n",
                                num_ports);
                }
                if (of_device_is_compatible(np, "aspeed,ast2400-uhci") ||
                    of_device_is_compatible(np, "aspeed,ast2500-uhci") ||
                    of_device_is_compatible(np, "aspeed,ast2600-uhci") ||
                    of_device_is_compatible(np, "aspeed,ast2700-uhci")) {
                        uhci->is_aspeed = 1;
                        dev_info(&pdev->dev,
                                 "Enabled Aspeed implementation workarounds\n");
                }
        }

        /* Get and enable clock if any specified */
        uhci->clk = devm_clk_get_optional(&pdev->dev, NULL);
        if (IS_ERR(uhci->clk)) {
                ret = PTR_ERR(uhci->clk);
                goto err_rmr;
        }
        ret = clk_prepare_enable(uhci->clk);
        if (ret) {
                dev_err(&pdev->dev, "Error couldn't enable clock (%d)\n", ret);
                goto err_rmr;
        }

        uhci->rsts = devm_reset_control_array_get_optional_shared(&pdev->dev);
        if (IS_ERR(uhci->rsts)) {
                ret = PTR_ERR(uhci->rsts);
                goto err_clk;
        }
        ret = reset_control_deassert(uhci->rsts);
        if (ret)
                goto err_clk;

        ret = platform_get_irq(pdev, 0);
        if (ret < 0)
                goto err_reset;

        ret = usb_add_hcd(hcd, ret, IRQF_SHARED);
        if (ret)
                goto err_reset;

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

err_reset:
        reset_control_assert(uhci->rsts);
err_clk:
        clk_disable_unprepare(uhci->clk);
err_rmr:
        usb_put_hcd(hcd);

        return ret;
}

static void uhci_hcd_platform_remove(struct platform_device *pdev)
{
        struct usb_hcd *hcd = platform_get_drvdata(pdev);
        struct uhci_hcd *uhci = hcd_to_uhci(hcd);

        reset_control_assert(uhci->rsts);
        clk_disable_unprepare(uhci->clk);
        usb_remove_hcd(hcd);
        usb_put_hcd(hcd);
}

/* Make sure the controller is quiescent and that we're not using it
 * any more.  This is mainly for the benefit of programs which, like kexec,
 * expect the hardware to be idle: not doing DMA or generating IRQs.
 *
 * This routine may be called in a damaged or failing kernel.  Hence we
 * do not acquire the spinlock before shutting down the controller.
 */
static void uhci_hcd_platform_shutdown(struct platform_device *op)
{
        struct usb_hcd *hcd = platform_get_drvdata(op);

        uhci_hc_died(hcd_to_uhci(hcd));
}

static const struct of_device_id platform_uhci_ids[] = {
        { .compatible = "generic-uhci", },
        { .compatible = "platform-uhci", },
        { .compatible = "aspeed,ast2700-uhci", .data = (void *)1 },
        {}
};
MODULE_DEVICE_TABLE(of, platform_uhci_ids);

static struct platform_driver uhci_platform_driver = {
        .probe          = uhci_hcd_platform_probe,
        .remove         = uhci_hcd_platform_remove,
        .shutdown       = uhci_hcd_platform_shutdown,
        .driver = {
                .name = "platform-uhci",
                .of_match_table = platform_uhci_ids,
        },
};
MODULE_SOFTDEP("pre: ehci_platform");