// SPDX-License-Identifier: GPL-2.0
/*
 * Copyright (C) 2005-2007 by Texas Instruments
 * Some code has been taken from tusb6010.c
 * Copyrights for that are attributable to:
 * Copyright (C) 2006 Nokia Corporation
 * Tony Lindgren <tony@atomide.com>
 *
 * This file is part of the Inventra Controller Driver for Linux.
 */
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/init.h>
#include <linux/list.h>
#include <linux/io.h>
#include <linux/of.h>
#include <linux/of_irq.h>
#include <linux/platform_device.h>
#include <linux/dma-mapping.h>
#include <linux/pm_runtime.h>
#include <linux/err.h>
#include <linux/delay.h>
#include <linux/usb/musb.h>
#include <linux/phy/omap_control_phy.h>
#include <linux/of_platform.h>

#include "musb_core.h"
#include "omap2430.h"

struct omap2430_glue {
        struct device           *dev;
        struct platform_device  *musb;
        enum musb_vbus_id_status status;
        struct work_struct      omap_musb_mailbox_work;
        struct device           *control_otghs;
        unsigned int            is_runtime_suspended:1;
        unsigned int            needs_resume:1;
        unsigned int            phy_suspended:1;
};
#define glue_to_musb(g)         platform_get_drvdata(g->musb)

static struct omap2430_glue     *_glue;

static inline void omap2430_low_level_exit(struct musb *musb)
{
        u32 l;

        /* in any role */
        l = musb_readl(musb->mregs, OTG_FORCESTDBY);
        l |= ENABLEFORCE;       /* enable MSTANDBY */
        musb_writel(musb->mregs, OTG_FORCESTDBY, l);
}

static inline void omap2430_low_level_init(struct musb *musb)
{
        u32 l;

        l = musb_readl(musb->mregs, OTG_FORCESTDBY);
        l &= ~ENABLEFORCE;      /* disable MSTANDBY */
        musb_writel(musb->mregs, OTG_FORCESTDBY, l);
}

static int omap2430_musb_mailbox(enum musb_vbus_id_status status)
{
        struct omap2430_glue    *glue = _glue;

        if (!glue) {
                pr_err("%s: musb core is not yet initialized\n", __func__);
                return -EPROBE_DEFER;
        }
        glue->status = status;

        if (!glue_to_musb(glue)) {
                pr_err("%s: musb core is not yet ready\n", __func__);
                return -EPROBE_DEFER;
        }

        schedule_work(&glue->omap_musb_mailbox_work);

        return 0;
}

/*
 * HDRC controls CPEN, but beware current surges during device connect.
 * They can trigger transient overcurrent conditions that must be ignored.
 *
 * Note that we're skipping A_WAIT_VFALL -> A_IDLE and jumping right to B_IDLE
 * as set by musb_set_peripheral().
 */
static void omap_musb_set_mailbox(struct omap2430_glue *glue)
{
        struct musb *musb = glue_to_musb(glue);
        int error;

        pm_runtime_get_sync(musb->controller);

        dev_dbg(musb->controller, "VBUS %s, devctl %02x\n",
                usb_otg_state_string(musb->xceiv->otg->state),
                musb_readb(musb->mregs, MUSB_DEVCTL));

        switch (glue->status) {
        case MUSB_ID_GROUND:
                dev_dbg(musb->controller, "ID GND\n");
                switch (musb->xceiv->otg->state) {
                case OTG_STATE_A_IDLE:
                        error = musb_set_host(musb);
                        if (error)
                                break;
                        musb->xceiv->otg->state = OTG_STATE_A_WAIT_VRISE;
                        fallthrough;
                case OTG_STATE_A_WAIT_VRISE:
                case OTG_STATE_A_WAIT_BCON:
                case OTG_STATE_A_HOST:
                        /*
                         * On multiple ID ground interrupts just keep enabling
                         * VBUS. At least cpcap VBUS shuts down otherwise.
                         */
                        otg_set_vbus(musb->xceiv->otg, 1);
                        break;
                default:
                        musb->xceiv->otg->state = OTG_STATE_A_IDLE;
                        musb->xceiv->last_event = USB_EVENT_ID;
                        if (musb->gadget_driver) {
                                omap_control_usb_set_mode(glue->control_otghs,
                                                          USB_MODE_HOST);
                                otg_set_vbus(musb->xceiv->otg, 1);
                        }
                        break;
                }
                break;

        case MUSB_VBUS_VALID:
                dev_dbg(musb->controller, "VBUS Connect\n");

                musb->xceiv->otg->state = OTG_STATE_B_IDLE;
                musb->xceiv->last_event = USB_EVENT_VBUS;
                omap_control_usb_set_mode(glue->control_otghs, USB_MODE_DEVICE);
                break;

        case MUSB_ID_FLOAT:
        case MUSB_VBUS_OFF:
                dev_dbg(musb->controller, "VBUS Disconnect\n");

                musb->xceiv->last_event = USB_EVENT_NONE;
                musb_set_peripheral(musb);
                otg_set_vbus(musb->xceiv->otg, 0);
                omap_control_usb_set_mode(glue->control_otghs,
                        USB_MODE_DISCONNECT);
                break;
        default:
                dev_dbg(musb->controller, "ID float\n");
        }
        pm_runtime_put_autosuspend(musb->controller);
        atomic_notifier_call_chain(&musb->xceiv->notifier,
                        musb->xceiv->last_event, NULL);
}


static void omap_musb_mailbox_work(struct work_struct *mailbox_work)
{
        struct omap2430_glue *glue = container_of(mailbox_work,
                                struct omap2430_glue, omap_musb_mailbox_work);

        omap_musb_set_mailbox(glue);
}

static irqreturn_t omap2430_musb_interrupt(int irq, void *__hci)
{
        unsigned long   flags;
        irqreturn_t     retval = IRQ_NONE;
        struct musb     *musb = __hci;

        spin_lock_irqsave(&musb->lock, flags);

        musb->int_usb = musb_readb(musb->mregs, MUSB_INTRUSB);
        musb->int_tx = musb_readw(musb->mregs, MUSB_INTRTX);
        musb->int_rx = musb_readw(musb->mregs, MUSB_INTRRX);

        if (musb->int_usb || musb->int_tx || musb->int_rx)
                retval = musb_interrupt(musb);

        spin_unlock_irqrestore(&musb->lock, flags);

        return retval;
}

static int omap2430_musb_init(struct musb *musb)
{
        u32 l;
        int status = 0;
        struct device *dev = musb->controller;
        struct musb_hdrc_platform_data *plat = dev_get_platdata(dev);
        struct omap_musb_board_data *data = plat->board_data;

        /* We require some kind of external transceiver, hooked
         * up through ULPI.  TWL4030-family PMICs include one,
         * which needs a driver, drivers aren't always needed.
         */
        musb->phy = devm_phy_get(dev->parent, "usb2-phy");

        /* We can't totally remove musb->xceiv as of now because
         * musb core uses xceiv.state and xceiv.otg. Once we have
         * a separate state machine to handle otg, these can be moved
         * out of xceiv and then we can start using the generic PHY
         * framework
         */
        musb->xceiv = devm_usb_get_phy_by_phandle(dev->parent, "usb-phy", 0);

        if (IS_ERR(musb->xceiv)) {
                status = PTR_ERR(musb->xceiv);

                if (status == -ENXIO)
                        return status;

                dev_dbg(dev, "HS USB OTG: no transceiver configured\n");
                return -EPROBE_DEFER;
        }

        if (IS_ERR(musb->phy)) {
                dev_err(dev, "HS USB OTG: no PHY configured\n");
                return PTR_ERR(musb->phy);
        }
        musb->isr = omap2430_musb_interrupt;
        phy_init(musb->phy);
        phy_power_on(musb->phy);

        l = musb_readl(musb->mregs, OTG_INTERFSEL);

        if (data->interface_type == MUSB_INTERFACE_UTMI) {
                /* OMAP4 uses Internal PHY GS70 which uses UTMI interface */
                l &= ~ULPI_12PIN;       /* Disable ULPI */
                l |= UTMI_8BIT;         /* Enable UTMI  */
        } else {
                l |= ULPI_12PIN;
        }

        musb_writel(musb->mregs, OTG_INTERFSEL, l);

        dev_dbg(dev, "HS USB OTG: revision 0x%x, sysconfig 0x%02x, "
                        "sysstatus 0x%x, intrfsel 0x%x, simenable  0x%x\n",
                        musb_readl(musb->mregs, OTG_REVISION),
                        musb_readl(musb->mregs, OTG_SYSCONFIG),
                        musb_readl(musb->mregs, OTG_SYSSTATUS),
                        musb_readl(musb->mregs, OTG_INTERFSEL),
                        musb_readl(musb->mregs, OTG_SIMENABLE));

        return 0;
}

static void omap2430_musb_enable(struct musb *musb)
{
        struct device *dev = musb->controller;
        struct omap2430_glue *glue = dev_get_drvdata(dev->parent);

        if (glue->status == MUSB_UNKNOWN)
                glue->status = MUSB_VBUS_OFF;
        omap_musb_set_mailbox(glue);
}

static void omap2430_musb_disable(struct musb *musb)
{
        struct device *dev = musb->controller;
        struct omap2430_glue *glue = dev_get_drvdata(dev->parent);

        if (glue->status != MUSB_UNKNOWN)
                omap_control_usb_set_mode(glue->control_otghs,
                        USB_MODE_DISCONNECT);
}

static int omap2430_musb_exit(struct musb *musb)
{
        struct device *dev = musb->controller;
        struct omap2430_glue *glue = dev_get_drvdata(dev->parent);

        omap2430_low_level_exit(musb);
        phy_power_off(musb->phy);
        phy_exit(musb->phy);
        musb->phy = NULL;
        cancel_work_sync(&glue->omap_musb_mailbox_work);

        return 0;
}

static const struct musb_platform_ops omap2430_ops = {
        .quirks         = MUSB_DMA_INVENTRA,
#ifdef CONFIG_USB_INVENTRA_DMA
        .dma_init       = musbhs_dma_controller_create,
        .dma_exit       = musbhs_dma_controller_destroy,
#endif
        .init           = omap2430_musb_init,
        .exit           = omap2430_musb_exit,

        .enable         = omap2430_musb_enable,
        .disable        = omap2430_musb_disable,

        .phy_callback   = omap2430_musb_mailbox,
};

static u64 omap2430_dmamask = DMA_BIT_MASK(32);

static int omap2430_probe(struct platform_device *pdev)
{
        struct musb_hdrc_platform_data  *pdata = dev_get_platdata(&pdev->dev);
        struct omap_musb_board_data     *data;
        struct platform_device          *musb;
        struct omap2430_glue            *glue;
        struct device_node              *np = pdev->dev.of_node;
        struct musb_hdrc_config         *config;
        struct device_node              *control_node;
        struct platform_device          *control_pdev;
        int                             ret = -ENOMEM, val;
        bool                            populate_irqs = false;

        if (!np)
                return -ENODEV;

        glue = devm_kzalloc(&pdev->dev, sizeof(*glue), GFP_KERNEL);
        if (!glue)
                return -ENOMEM;

        musb = platform_device_alloc("musb-hdrc", PLATFORM_DEVID_AUTO);
        if (!musb)
                return -ENOMEM;

        musb->dev.parent                = &pdev->dev;
        musb->dev.dma_mask              = &omap2430_dmamask;
        musb->dev.coherent_dma_mask     = omap2430_dmamask;

        /*
         * Legacy SoCs using omap_device get confused if node is moved
         * because of interconnect properties mixed into the node.
         */
        if (of_property_present(np, "ti,hwmods")) {
                dev_warn(&pdev->dev, "please update to probe with ti-sysc\n");
                populate_irqs = true;
        } else {
                device_set_of_node_from_dev(&musb->dev, &pdev->dev);
        }
        of_node_put(np);

        glue->dev                       = &pdev->dev;
        glue->musb                      = musb;
        glue->status                    = MUSB_UNKNOWN;
        glue->control_otghs = ERR_PTR(-ENODEV);

        pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
        if (!pdata)
                goto err_put_musb;

        data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
        if (!data)
                goto err_put_musb;

        config = devm_kzalloc(&pdev->dev, sizeof(*config), GFP_KERNEL);
        if (!config)
                goto err_put_musb;

        of_property_read_u32(np, "mode", (u32 *)&pdata->mode);
        of_property_read_u32(np, "interface-type",
                        (u32 *)&data->interface_type);
        of_property_read_u32(np, "num-eps", (u32 *)&config->num_eps);
        of_property_read_u32(np, "ram-bits", (u32 *)&config->ram_bits);
        of_property_read_u32(np, "power", (u32 *)&pdata->power);

        ret = of_property_read_u32(np, "multipoint", &val);
        if (!ret && val)
                config->multipoint = true;

        pdata->board_data       = data;
        pdata->config           = config;

        control_node = of_parse_phandle(np, "ctrl-module", 0);
        if (control_node) {
                control_pdev = of_find_device_by_node(control_node);
                of_node_put(control_node);
                if (!control_pdev) {
                        dev_err(&pdev->dev, "Failed to get control device\n");
                        ret = -EINVAL;
                        goto err_put_musb;
                }
                glue->control_otghs = &control_pdev->dev;
        }

        pdata->platform_ops             = &omap2430_ops;

        platform_set_drvdata(pdev, glue);

        /*
         * REVISIT if we ever have two instances of the wrapper, we will be
         * in big trouble
         */
        _glue   = glue;

        INIT_WORK(&glue->omap_musb_mailbox_work, omap_musb_mailbox_work);

        ret = platform_device_add_resources(musb, pdev->resource, pdev->num_resources);
        if (ret) {
                dev_err(&pdev->dev, "failed to add resources\n");
                goto err_put_control_otghs;
        }

        if (populate_irqs) {
                struct resource musb_res[3];
                struct resource *res;
                int i = 0;

                memset(musb_res, 0, sizeof(*musb_res) * ARRAY_SIZE(musb_res));

                res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
                if (!res) {
                        ret = -EINVAL;
                        goto err_put_control_otghs;
                }

                musb_res[i].start = res->start;
                musb_res[i].end = res->end;
                musb_res[i].flags = res->flags;
                musb_res[i].name = res->name;
                i++;

                ret = of_irq_get_byname(np, "mc");
                if (ret > 0) {
                        musb_res[i].start = ret;
                        musb_res[i].flags = IORESOURCE_IRQ;
                        musb_res[i].name = "mc";
                        i++;
                }

                ret = of_irq_get_byname(np, "dma");
                if (ret > 0) {
                        musb_res[i].start = ret;
                        musb_res[i].flags = IORESOURCE_IRQ;
                        musb_res[i].name = "dma";
                        i++;
                }

                ret = platform_device_add_resources(musb, musb_res, i);
                if (ret) {
                        dev_err(&pdev->dev, "failed to add IRQ resources\n");
                        goto err_put_control_otghs;
                }
        }

        ret = platform_device_add_data(musb, pdata, sizeof(*pdata));
        if (ret) {
                dev_err(&pdev->dev, "failed to add platform_data\n");
                goto err_put_control_otghs;
        }

        pm_runtime_enable(glue->dev);

        ret = platform_device_add(musb);
        if (ret) {
                dev_err(&pdev->dev, "failed to register musb device\n");
                goto err_disable_rpm;
        }

        return 0;

err_disable_rpm:
        pm_runtime_disable(glue->dev);
err_put_control_otghs:
        if (!IS_ERR(glue->control_otghs))
                put_device(glue->control_otghs);
err_put_musb:
        platform_device_put(musb);

        return ret;
}

static void omap2430_remove(struct platform_device *pdev)
{
        struct omap2430_glue *glue = platform_get_drvdata(pdev);

        platform_device_unregister(glue->musb);
        pm_runtime_disable(glue->dev);
        if (!IS_ERR(glue->control_otghs))
                put_device(glue->control_otghs);
}

#ifdef CONFIG_PM

static int omap2430_runtime_suspend(struct device *dev)
{
        struct omap2430_glue            *glue = dev_get_drvdata(dev);
        struct musb                     *musb = glue_to_musb(glue);

        if (!musb)
                return 0;

        musb->context.otg_interfsel = musb_readl(musb->mregs,
                                                 OTG_INTERFSEL);

        omap2430_low_level_exit(musb);

        if (!glue->phy_suspended) {
                phy_power_off(musb->phy);
                phy_exit(musb->phy);
        }

        glue->is_runtime_suspended = 1;

        return 0;
}

static int omap2430_runtime_resume(struct device *dev)
{
        struct omap2430_glue            *glue = dev_get_drvdata(dev);
        struct musb                     *musb = glue_to_musb(glue);

        if (!musb)
                return 0;

        if (!glue->phy_suspended) {
                phy_init(musb->phy);
                phy_power_on(musb->phy);
        }

        omap2430_low_level_init(musb);
        musb_writel(musb->mregs, OTG_INTERFSEL,
                    musb->context.otg_interfsel);

        /* Wait for musb to get oriented. Otherwise we can get babble */
        usleep_range(200000, 250000);

        glue->is_runtime_suspended = 0;

        return 0;
}

/* I2C and SPI PHYs need to be suspended before the glue layer */
static int omap2430_suspend(struct device *dev)
{
        struct omap2430_glue *glue = dev_get_drvdata(dev);
        struct musb *musb = glue_to_musb(glue);

        phy_power_off(musb->phy);
        phy_exit(musb->phy);
        glue->phy_suspended = 1;

        return 0;
}

/* Glue layer needs to be suspended after musb_suspend() */
static int omap2430_suspend_late(struct device *dev)
{
        struct omap2430_glue *glue = dev_get_drvdata(dev);

        if (glue->is_runtime_suspended)
                return 0;

        glue->needs_resume = 1;

        return omap2430_runtime_suspend(dev);
}

static int omap2430_resume_early(struct device *dev)
{
        struct omap2430_glue *glue = dev_get_drvdata(dev);

        if (!glue->needs_resume)
                return 0;

        glue->needs_resume = 0;

        return omap2430_runtime_resume(dev);
}

static int omap2430_resume(struct device *dev)
{
        struct omap2430_glue *glue = dev_get_drvdata(dev);
        struct musb *musb = glue_to_musb(glue);

        phy_init(musb->phy);
        phy_power_on(musb->phy);
        glue->phy_suspended = 0;

        return 0;
}

static const struct dev_pm_ops omap2430_pm_ops = {
        .runtime_suspend = omap2430_runtime_suspend,
        .runtime_resume = omap2430_runtime_resume,
        .suspend = omap2430_suspend,
        .suspend_late = omap2430_suspend_late,
        .resume_early = omap2430_resume_early,
        .resume = omap2430_resume,
};

#define DEV_PM_OPS      (&omap2430_pm_ops)
#else
#define DEV_PM_OPS      NULL
#endif

#ifdef CONFIG_OF
static const struct of_device_id omap2430_id_table[] = {
        {
                .compatible = "ti,omap4-musb"
        },
        {
                .compatible = "ti,omap3-musb"
        },
        {},
};
MODULE_DEVICE_TABLE(of, omap2430_id_table);
#endif

static struct platform_driver omap2430_driver = {
        .probe          = omap2430_probe,
        .remove         = omap2430_remove,
        .driver         = {
                .name   = "musb-omap2430",
                .pm     = DEV_PM_OPS,
                .of_match_table = of_match_ptr(omap2430_id_table),
        },
};

module_platform_driver(omap2430_driver);

MODULE_DESCRIPTION("OMAP2PLUS MUSB Glue Layer");
MODULE_AUTHOR("Felipe Balbi <balbi@ti.com>");
MODULE_LICENSE("GPL v2");