// SPDX-License-Identifier: GPL-2.0
/*
 * snps_udc_plat.c - Synopsys UDC Platform Driver
 *
 * Copyright (C) 2016 Broadcom
 */

#include <linux/extcon.h>
#include <linux/of_address.h>
#include <linux/of_irq.h>
#include <linux/platform_device.h>
#include <linux/phy/phy.h>
#include <linux/module.h>
#include <linux/dmapool.h>
#include <linux/interrupt.h>
#include <linux/moduleparam.h>
#include "amd5536udc.h"

/* description */
#define UDC_MOD_DESCRIPTION     "Synopsys UDC platform driver"

static void start_udc(struct udc *udc)
{
        if (udc->driver) {
                dev_info(udc->dev, "Connecting...\n");
                udc_enable_dev_setup_interrupts(udc);
                udc_basic_init(udc);
                udc->connected = 1;
        }
}

static void stop_udc(struct udc *udc)
{
        int tmp;
        u32 reg;

        spin_lock(&udc->lock);

        /* Flush the receieve fifo */
        reg = readl(&udc->regs->ctl);
        reg |= AMD_BIT(UDC_DEVCTL_SRX_FLUSH);
        writel(reg, &udc->regs->ctl);

        reg = readl(&udc->regs->ctl);
        reg &= ~(AMD_BIT(UDC_DEVCTL_SRX_FLUSH));
        writel(reg, &udc->regs->ctl);
        dev_dbg(udc->dev, "ep rx queue flushed\n");

        /* Mask interrupts. Required more so when the
         * UDC is connected to a DRD phy.
         */
        udc_mask_unused_interrupts(udc);

        /* Disconnect gadget driver */
        if (udc->driver) {
                spin_unlock(&udc->lock);
                udc->driver->disconnect(&udc->gadget);
                spin_lock(&udc->lock);

                /* empty queues */
                for (tmp = 0; tmp < UDC_EP_NUM; tmp++)
                        empty_req_queue(&udc->ep[tmp]);
        }
        udc->connected = 0;

        spin_unlock(&udc->lock);
        dev_info(udc->dev, "Device disconnected\n");
}

static void udc_drd_work(struct work_struct *work)
{
        struct udc *udc;

        udc = container_of(to_delayed_work(work),
                           struct udc, drd_work);

        if (udc->conn_type) {
                dev_dbg(udc->dev, "idle -> device\n");
                start_udc(udc);
        } else {
                dev_dbg(udc->dev, "device -> idle\n");
                stop_udc(udc);
        }
}

static int usbd_connect_notify(struct notifier_block *self,
                               unsigned long event, void *ptr)
{
        struct udc *udc = container_of(self, struct udc, nb);

        dev_dbg(udc->dev, "%s: event: %lu\n", __func__, event);

        udc->conn_type = event;

        schedule_delayed_work(&udc->drd_work, 0);

        return NOTIFY_OK;
}

static int udc_plat_probe(struct platform_device *pdev)
{
        struct device *dev = &pdev->dev;
        struct resource *res;
        struct udc *udc;
        int ret;

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

        spin_lock_init(&udc->lock);
        udc->dev = dev;

        udc->virt_addr = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
        if (IS_ERR(udc->virt_addr))
                return PTR_ERR(udc->virt_addr);

        /* udc csr registers base */
        udc->csr = udc->virt_addr + UDC_CSR_ADDR;

        /* dev registers base */
        udc->regs = udc->virt_addr + UDC_DEVCFG_ADDR;

        /* ep registers base */
        udc->ep_regs = udc->virt_addr + UDC_EPREGS_ADDR;

        /* fifo's base */
        udc->rxfifo = (u32 __iomem *)(udc->virt_addr + UDC_RXFIFO_ADDR);
        udc->txfifo = (u32 __iomem *)(udc->virt_addr + UDC_TXFIFO_ADDR);

        udc->phys_addr = (unsigned long)res->start;

        udc->irq = irq_of_parse_and_map(dev->of_node, 0);
        if (udc->irq <= 0) {
                dev_err(dev, "Can't parse and map interrupt\n");
                return -EINVAL;
        }

        udc->udc_phy = devm_of_phy_get_by_index(dev, dev->of_node, 0);
        if (IS_ERR(udc->udc_phy)) {
                dev_err(dev, "Failed to obtain phy from device tree\n");
                return PTR_ERR(udc->udc_phy);
        }

        ret = phy_init(udc->udc_phy);
        if (ret) {
                dev_err(dev, "UDC phy init failed");
                return ret;
        }

        ret = phy_power_on(udc->udc_phy);
        if (ret) {
                dev_err(dev, "UDC phy power on failed");
                phy_exit(udc->udc_phy);
                return ret;
        }

        /* Register for extcon if supported */
        if (of_property_present(dev->of_node, "extcon")) {
                udc->edev = extcon_get_edev_by_phandle(dev, 0);
                if (IS_ERR(udc->edev)) {
                        if (PTR_ERR(udc->edev) == -EPROBE_DEFER)
                                return -EPROBE_DEFER;
                        dev_err(dev, "Invalid or missing extcon\n");
                        ret = PTR_ERR(udc->edev);
                        goto exit_phy;
                }

                udc->nb.notifier_call = usbd_connect_notify;
                ret = extcon_register_notifier(udc->edev, EXTCON_USB,
                                               &udc->nb);
                if (ret < 0) {
                        dev_err(dev, "Can't register extcon device\n");
                        goto exit_phy;
                }

                ret = extcon_get_state(udc->edev, EXTCON_USB);
                if (ret < 0) {
                        dev_err(dev, "Can't get cable state\n");
                        goto exit_extcon;
                } else if (ret) {
                        udc->conn_type = ret;
                }
                INIT_DELAYED_WORK(&udc->drd_work, udc_drd_work);
        }

        /* init dma pools */
        if (use_dma) {
                ret = init_dma_pools(udc);
                if (ret != 0)
                        goto exit_extcon;
        }

        ret = devm_request_irq(dev, udc->irq, udc_irq, IRQF_SHARED,
                               "snps-udc", udc);
        if (ret < 0) {
                dev_err(dev, "Request irq %d failed for UDC\n", udc->irq);
                goto exit_dma;
        }

        platform_set_drvdata(pdev, udc);
        udc->chiprev = UDC_BCM_REV;

        if (udc_probe(udc)) {
                ret = -ENODEV;
                goto exit_dma;
        }
        dev_info(dev, "Synopsys UDC platform driver probe successful\n");

        return 0;

exit_dma:
        if (use_dma)
                free_dma_pools(udc);
exit_extcon:
        if (udc->edev)
                extcon_unregister_notifier(udc->edev, EXTCON_USB, &udc->nb);
exit_phy:
        if (udc->udc_phy) {
                phy_power_off(udc->udc_phy);
                phy_exit(udc->udc_phy);
        }
        return ret;
}

static void udc_plat_remove(struct platform_device *pdev)
{
        struct udc *dev;

        dev = platform_get_drvdata(pdev);

        usb_del_gadget_udc(&dev->gadget);
        /* gadget driver must not be registered */
        if (WARN_ON(dev->driver))
                return;

        /* dma pool cleanup */
        free_dma_pools(dev);

        udc_remove(dev);

        platform_set_drvdata(pdev, NULL);

        phy_power_off(dev->udc_phy);
        phy_exit(dev->udc_phy);
        extcon_unregister_notifier(dev->edev, EXTCON_USB, &dev->nb);

        dev_info(&pdev->dev, "Synopsys UDC platform driver removed\n");
}

#ifdef CONFIG_PM_SLEEP
static int udc_plat_suspend(struct device *dev)
{
        struct udc *udc;

        udc = dev_get_drvdata(dev);
        stop_udc(udc);

        if (extcon_get_state(udc->edev, EXTCON_USB) > 0) {
                dev_dbg(udc->dev, "device -> idle\n");
                stop_udc(udc);
        }
        phy_power_off(udc->udc_phy);
        phy_exit(udc->udc_phy);

        return 0;
}

static int udc_plat_resume(struct device *dev)
{
        struct udc *udc;
        int ret;

        udc = dev_get_drvdata(dev);

        ret = phy_init(udc->udc_phy);
        if (ret) {
                dev_err(udc->dev, "UDC phy init failure");
                return ret;
        }

        ret = phy_power_on(udc->udc_phy);
        if (ret) {
                dev_err(udc->dev, "UDC phy power on failure");
                phy_exit(udc->udc_phy);
                return ret;
        }

        if (extcon_get_state(udc->edev, EXTCON_USB) > 0) {
                dev_dbg(udc->dev, "idle -> device\n");
                start_udc(udc);
        }

        return 0;
}
static const struct dev_pm_ops udc_plat_pm_ops = {
        .suspend        = udc_plat_suspend,
        .resume         = udc_plat_resume,
};
#endif

static const struct of_device_id of_udc_match[] = {
        { .compatible = "brcm,ns2-udc", },
        { .compatible = "brcm,cygnus-udc", },
        { .compatible = "brcm,iproc-udc", },
        { }
};
MODULE_DEVICE_TABLE(of, of_udc_match);

static struct platform_driver udc_plat_driver = {
        .probe          = udc_plat_probe,
        .remove         = udc_plat_remove,
        .driver         = {
                .name   = "snps-udc-plat",
                .of_match_table = of_udc_match,
#ifdef CONFIG_PM_SLEEP
                .pm     = &udc_plat_pm_ops,
#endif
        },
};
module_platform_driver(udc_plat_driver);

MODULE_DESCRIPTION(UDC_MOD_DESCRIPTION);
MODULE_AUTHOR("Broadcom");
MODULE_LICENSE("GPL v2");