// SPDX-License-Identifier: GPL-2.0+
/*
 * Ingenic JZ4740 "glue layer"
 *
 * Copyright (C) 2013, Apelete Seketeli <apelete@seketeli.net>
 */

#include <linux/clk.h>
#include <linux/dma-mapping.h>
#include <linux/errno.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/of_device.h>
#include <linux/platform_device.h>
#include <linux/usb/usb_phy_generic.h>

#include "musb_core.h"

struct jz4740_glue {
        struct device           *dev;
        struct platform_device  *musb;
        struct clk              *clk;
};

static irqreturn_t jz4740_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);

        /*
         * The controller is gadget only, the state of the host mode IRQ bits is
         * undefined. Mask them to make sure that the musb driver core will
         * never see them set
         */
        musb->int_usb &= MUSB_INTR_SUSPEND | MUSB_INTR_RESUME |
            MUSB_INTR_RESET | MUSB_INTR_SOF;

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

        spin_unlock_irqrestore(&musb->lock, flags);

        return retval;
}

static struct musb_fifo_cfg jz4740_musb_fifo_cfg[] = {
{ .hw_ep_num = 1, .style = FIFO_TX, .maxpacket = 512, },
{ .hw_ep_num = 1, .style = FIFO_RX, .maxpacket = 512, },
{ .hw_ep_num = 2, .style = FIFO_TX, .maxpacket = 64, },
};

static const struct musb_hdrc_config jz4740_musb_config = {
        /* Silicon does not implement USB OTG. */
        .multipoint = 0,
        /* Max EPs scanned, driver will decide which EP can be used. */
        .num_eps    = 4,
        /* RAMbits needed to configure EPs from table */
        .ram_bits   = 9,
        .fifo_cfg = jz4740_musb_fifo_cfg,
        .fifo_cfg_size = ARRAY_SIZE(jz4740_musb_fifo_cfg),
};

static struct musb_hdrc_platform_data jz4740_musb_platform_data = {
        .mode   = MUSB_PERIPHERAL,
        .config = &jz4740_musb_config,
};

static int jz4740_musb_init(struct musb *musb)
{
        struct device *dev = musb->controller->parent;

        if (dev->of_node)
                musb->xceiv = devm_usb_get_phy_by_phandle(dev, "phys", 0);
        else
                musb->xceiv = devm_usb_get_phy(dev, USB_PHY_TYPE_USB2);
        if (IS_ERR(musb->xceiv)) {
                dev_err(dev, "No transceiver configured\n");
                return PTR_ERR(musb->xceiv);
        }

        /* Silicon does not implement ConfigData register.
         * Set dyn_fifo to avoid reading EP config from hardware.
         */
        musb->dyn_fifo = true;

        musb->isr = jz4740_musb_interrupt;

        return 0;
}

/*
 * DMA has not been confirmed to work with CONFIG_USB_INVENTRA_DMA,
 * so let's not set up the dma function pointers yet.
 */
static const struct musb_platform_ops jz4740_musb_ops = {
        .quirks         = MUSB_DMA_INVENTRA | MUSB_INDEXED_EP,
        .fifo_mode      = 2,
        .init           = jz4740_musb_init,
};

static int jz4740_probe(struct platform_device *pdev)
{
        struct musb_hdrc_platform_data  *pdata = &jz4740_musb_platform_data;
        struct platform_device          *musb;
        struct jz4740_glue              *glue;
        struct clk                      *clk;
        int                             ret;

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

        musb = platform_device_alloc("musb-hdrc", PLATFORM_DEVID_AUTO);
        if (!musb) {
                dev_err(&pdev->dev, "failed to allocate musb device\n");
                return -ENOMEM;
        }

        clk = devm_clk_get(&pdev->dev, "udc");
        if (IS_ERR(clk)) {
                dev_err(&pdev->dev, "failed to get clock\n");
                ret = PTR_ERR(clk);
                goto err_platform_device_put;
        }

        ret = clk_prepare_enable(clk);
        if (ret) {
                dev_err(&pdev->dev, "failed to enable clock\n");
                goto err_platform_device_put;
        }

        musb->dev.parent                = &pdev->dev;

        glue->dev                       = &pdev->dev;
        glue->musb                      = musb;
        glue->clk                       = clk;

        pdata->platform_ops             = &jz4740_musb_ops;

        platform_set_drvdata(pdev, glue);

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

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

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

        return 0;

err_clk_disable:
        clk_disable_unprepare(clk);
err_platform_device_put:
        platform_device_put(musb);
        return ret;
}

static int jz4740_remove(struct platform_device *pdev)
{
        struct jz4740_glue      *glue = platform_get_drvdata(pdev);

        platform_device_unregister(glue->musb);
        clk_disable_unprepare(glue->clk);

        return 0;
}

#ifdef CONFIG_OF
static const struct of_device_id jz4740_musb_of_match[] = {
        { .compatible = "ingenic,jz4740-musb" },
        {},
};
MODULE_DEVICE_TABLE(of, jz4740_musb_of_match);
#endif

static struct platform_driver jz4740_driver = {
        .probe          = jz4740_probe,
        .remove         = jz4740_remove,
        .driver         = {
                .name   = "musb-jz4740",
                .of_match_table = of_match_ptr(jz4740_musb_of_match),
        },
};

MODULE_DESCRIPTION("JZ4740 MUSB Glue Layer");
MODULE_AUTHOR("Apelete Seketeli <apelete@seketeli.net>");
MODULE_LICENSE("GPL v2");
module_platform_driver(jz4740_driver);