/*
 * Renesas USB driver
 *
 * Copyright (C) 2011 Renesas Solutions Corp.
 * Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 *
 */
#include <linux/err.h>
#include <linux/io.h>
#include <linux/module.h>
#include <linux/pm_runtime.h>
#include <linux/slab.h>
#include <linux/sysfs.h>
#include "common.h"

/*
 *              image of renesas_usbhs
 *
 * ex) gadget case

 * mod.c
 * mod_gadget.c
 * mod_host.c           pipe.c          fifo.c
 *
 *                      +-------+       +-----------+
 *                      | pipe0 |------>| fifo pio  |
 * +------------+       +-------+       +-----------+
 * | mod_gadget |=====> | pipe1 |--+
 * +------------+       +-------+  |    +-----------+
 *                      | pipe2 |  |  +-| fifo dma0 |
 * +------------+       +-------+  |  | +-----------+
 * | mod_host   |       | pipe3 |<-|--+
 * +------------+       +-------+  |    +-----------+
 *                      | ....  |  +--->| fifo dma1 |
 *                      | ....  |       +-----------+
 */


#define USBHSF_RUNTIME_PWCTRL   (1 << 0)

/* status */
#define usbhsc_flags_init(p)   do {(p)->flags = 0; } while (0)
#define usbhsc_flags_set(p, b) ((p)->flags |=  (b))
#define usbhsc_flags_clr(p, b) ((p)->flags &= ~(b))
#define usbhsc_flags_has(p, b) ((p)->flags &   (b))

/*
 * platform call back
 *
 * renesas usb support platform callback function.
 * Below macro call it.
 * if platform doesn't have callback, it return 0 (no error)
 */
#define usbhs_platform_call(priv, func, args...)\
        (!(priv) ? -ENODEV :                    \
         !((priv)->pfunc.func) ? 0 :            \
         (priv)->pfunc.func(args))

/*
 *              common functions
 */
u16 usbhs_read(struct usbhs_priv *priv, u32 reg)
{
        return ioread16(priv->base + reg);
}

void usbhs_write(struct usbhs_priv *priv, u32 reg, u16 data)
{
        iowrite16(data, priv->base + reg);
}

void usbhs_bset(struct usbhs_priv *priv, u32 reg, u16 mask, u16 data)
{
        u16 val = usbhs_read(priv, reg);

        val &= ~mask;
        val |= data & mask;

        usbhs_write(priv, reg, val);
}

struct usbhs_priv *usbhs_pdev_to_priv(struct platform_device *pdev)
{
        return dev_get_drvdata(&pdev->dev);
}

/*
 *              syscfg functions
 */
static void usbhs_sys_clock_ctrl(struct usbhs_priv *priv, int enable)
{
        usbhs_bset(priv, SYSCFG, SCKE, enable ? SCKE : 0);
}

void usbhs_sys_host_ctrl(struct usbhs_priv *priv, int enable)
{
        u16 mask = DCFM | DRPD | DPRPU | HSE | USBE;
        u16 val  = DCFM | DRPD | HSE | USBE;
        int has_otg = usbhs_get_dparam(priv, has_otg);

        if (has_otg)
                usbhs_bset(priv, DVSTCTR, (EXTLP | PWEN), (EXTLP | PWEN));

        /*
         * if enable
         *
         * - select Host mode
         * - D+ Line/D- Line Pull-down
         */
        usbhs_bset(priv, SYSCFG, mask, enable ? val : 0);
}

void usbhs_sys_function_ctrl(struct usbhs_priv *priv, int enable)
{
        u16 mask = DCFM | DRPD | DPRPU | HSE | USBE;
        u16 val  = DPRPU | HSE | USBE;

        /*
         * if enable
         *
         * - select Function mode
         * - D+ Line Pull-up
         */
        usbhs_bset(priv, SYSCFG, mask, enable ? val : 0);
}

void usbhs_sys_function_pullup(struct usbhs_priv *priv, int enable)
{
        usbhs_bset(priv, SYSCFG, DPRPU, enable ? DPRPU : 0);
}

void usbhs_sys_set_test_mode(struct usbhs_priv *priv, u16 mode)
{
        usbhs_write(priv, TESTMODE, mode);
}

/*
 *              frame functions
 */
int usbhs_frame_get_num(struct usbhs_priv *priv)
{
        return usbhs_read(priv, FRMNUM) & FRNM_MASK;
}

/*
 *              usb request functions
 */
void usbhs_usbreq_get_val(struct usbhs_priv *priv, struct usb_ctrlrequest *req)
{
        u16 val;

        val = usbhs_read(priv, USBREQ);
        req->bRequest           = (val >> 8) & 0xFF;
        req->bRequestType       = (val >> 0) & 0xFF;

        req->wValue     = usbhs_read(priv, USBVAL);
        req->wIndex     = usbhs_read(priv, USBINDX);
        req->wLength    = usbhs_read(priv, USBLENG);
}

void usbhs_usbreq_set_val(struct usbhs_priv *priv, struct usb_ctrlrequest *req)
{
        usbhs_write(priv, USBREQ,  (req->bRequest << 8) | req->bRequestType);
        usbhs_write(priv, USBVAL,  req->wValue);
        usbhs_write(priv, USBINDX, req->wIndex);
        usbhs_write(priv, USBLENG, req->wLength);

        usbhs_bset(priv, DCPCTR, SUREQ, SUREQ);
}

/*
 *              bus/vbus functions
 */
void usbhs_bus_send_sof_enable(struct usbhs_priv *priv)
{
        u16 status = usbhs_read(priv, DVSTCTR) & (USBRST | UACT);

        if (status != USBRST) {
                struct device *dev = usbhs_priv_to_dev(priv);
                dev_err(dev, "usbhs should be reset\n");
        }

        usbhs_bset(priv, DVSTCTR, (USBRST | UACT), UACT);
}

void usbhs_bus_send_reset(struct usbhs_priv *priv)
{
        usbhs_bset(priv, DVSTCTR, (USBRST | UACT), USBRST);
}

int usbhs_bus_get_speed(struct usbhs_priv *priv)
{
        u16 dvstctr = usbhs_read(priv, DVSTCTR);

        switch (RHST & dvstctr) {
        case RHST_LOW_SPEED:
                return USB_SPEED_LOW;
        case RHST_FULL_SPEED:
                return USB_SPEED_FULL;
        case RHST_HIGH_SPEED:
                return USB_SPEED_HIGH;
        }

        return USB_SPEED_UNKNOWN;
}

int usbhs_vbus_ctrl(struct usbhs_priv *priv, int enable)
{
        struct platform_device *pdev = usbhs_priv_to_pdev(priv);

        return usbhs_platform_call(priv, set_vbus, pdev, enable);
}

static void usbhsc_bus_init(struct usbhs_priv *priv)
{
        usbhs_write(priv, DVSTCTR, 0);

        usbhs_vbus_ctrl(priv, 0);
}

/*
 *              device configuration
 */
int usbhs_set_device_config(struct usbhs_priv *priv, int devnum,
                           u16 upphub, u16 hubport, u16 speed)
{
        struct device *dev = usbhs_priv_to_dev(priv);
        u16 usbspd = 0;
        u32 reg = DEVADD0 + (2 * devnum);

        if (devnum > 10) {
                dev_err(dev, "cannot set speed to unknown device %d\n", devnum);
                return -EIO;
        }

        if (upphub > 0xA) {
                dev_err(dev, "unsupported hub number %d\n", upphub);
                return -EIO;
        }

        switch (speed) {
        case USB_SPEED_LOW:
                usbspd = USBSPD_SPEED_LOW;
                break;
        case USB_SPEED_FULL:
                usbspd = USBSPD_SPEED_FULL;
                break;
        case USB_SPEED_HIGH:
                usbspd = USBSPD_SPEED_HIGH;
                break;
        default:
                dev_err(dev, "unsupported speed %d\n", speed);
                return -EIO;
        }

        usbhs_write(priv, reg,  UPPHUB(upphub)  |
                                HUBPORT(hubport)|
                                USBSPD(usbspd));

        return 0;
}

/*
 *              local functions
 */
static void usbhsc_set_buswait(struct usbhs_priv *priv)
{
        int wait = usbhs_get_dparam(priv, buswait_bwait);

        /* set bus wait if platform have */
        if (wait)
                usbhs_bset(priv, BUSWAIT, 0x000F, wait);
}

/*
 *              platform default param
 */
static u32 usbhsc_default_pipe_type[] = {
                USB_ENDPOINT_XFER_CONTROL,
                USB_ENDPOINT_XFER_ISOC,
                USB_ENDPOINT_XFER_ISOC,
                USB_ENDPOINT_XFER_BULK,
                USB_ENDPOINT_XFER_BULK,
                USB_ENDPOINT_XFER_BULK,
                USB_ENDPOINT_XFER_INT,
                USB_ENDPOINT_XFER_INT,
                USB_ENDPOINT_XFER_INT,
                USB_ENDPOINT_XFER_INT,
};

/*
 *              power control
 */
static void usbhsc_power_ctrl(struct usbhs_priv *priv, int enable)
{
        struct platform_device *pdev = usbhs_priv_to_pdev(priv);
        struct device *dev = usbhs_priv_to_dev(priv);

        if (enable) {
                /* enable PM */
                pm_runtime_get_sync(dev);

                /* enable platform power */
                usbhs_platform_call(priv, power_ctrl, pdev, priv->base, enable);

                /* USB on */
                usbhs_sys_clock_ctrl(priv, enable);
        } else {
                /* USB off */
                usbhs_sys_clock_ctrl(priv, enable);

                /* disable platform power */
                usbhs_platform_call(priv, power_ctrl, pdev, priv->base, enable);

                /* disable PM */
                pm_runtime_put_sync(dev);
        }
}

/*
 *              hotplug
 */
static void usbhsc_hotplug(struct usbhs_priv *priv)
{
        struct platform_device *pdev = usbhs_priv_to_pdev(priv);
        struct usbhs_mod *mod = usbhs_mod_get_current(priv);
        int id;
        int enable;
        int ret;

        /*
         * get vbus status from platform
         */
        enable = usbhs_platform_call(priv, get_vbus, pdev);

        /*
         * get id from platform
         */
        id = usbhs_platform_call(priv, get_id, pdev);

        if (enable && !mod) {
                ret = usbhs_mod_change(priv, id);
                if (ret < 0)
                        return;

                dev_dbg(&pdev->dev, "%s enable\n", __func__);

                /* power on */
                if (usbhsc_flags_has(priv, USBHSF_RUNTIME_PWCTRL))
                        usbhsc_power_ctrl(priv, enable);

                /* bus init */
                usbhsc_set_buswait(priv);
                usbhsc_bus_init(priv);

                /* module start */
                usbhs_mod_call(priv, start, priv);

        } else if (!enable && mod) {
                dev_dbg(&pdev->dev, "%s disable\n", __func__);

                /* module stop */
                usbhs_mod_call(priv, stop, priv);

                /* bus init */
                usbhsc_bus_init(priv);

                /* power off */
                if (usbhsc_flags_has(priv, USBHSF_RUNTIME_PWCTRL))
                        usbhsc_power_ctrl(priv, enable);

                usbhs_mod_change(priv, -1);

                /* reset phy for next connection */
                usbhs_platform_call(priv, phy_reset, pdev);
        }
}

/*
 *              notify hotplug
 */
static void usbhsc_notify_hotplug(struct work_struct *work)
{
        struct usbhs_priv *priv = container_of(work,
                                               struct usbhs_priv,
                                               notify_hotplug_work.work);
        usbhsc_hotplug(priv);
}

static int usbhsc_drvcllbck_notify_hotplug(struct platform_device *pdev)
{
        struct usbhs_priv *priv = usbhs_pdev_to_priv(pdev);
        int delay = usbhs_get_dparam(priv, detection_delay);

        /*
         * This functions will be called in interrupt.
         * To make sure safety context,
         * use workqueue for usbhs_notify_hotplug
         */
        schedule_delayed_work(&priv->notify_hotplug_work,
                              msecs_to_jiffies(delay));
        return 0;
}

/*
 *              platform functions
 */
static int usbhs_probe(struct platform_device *pdev)
{
        struct renesas_usbhs_platform_info *info = pdev->dev.platform_data;
        struct renesas_usbhs_driver_callback *dfunc;
        struct usbhs_priv *priv;
        struct resource *res, *irq_res;
        int ret;

        /* check platform information */
        if (!info ||
            !info->platform_callback.get_id) {
                dev_err(&pdev->dev, "no platform information\n");
                return -EINVAL;
        }

        /* platform data */
        res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
        irq_res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
        if (!res || !irq_res) {
                dev_err(&pdev->dev, "Not enough Renesas USB platform resources.\n");
                return -ENODEV;
        }

        /* usb private data */
        priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
        if (!priv) {
                dev_err(&pdev->dev, "Could not allocate priv\n");
                return -ENOMEM;
        }

        priv->base = devm_ioremap_resource(&pdev->dev, res);
        if (IS_ERR(priv->base))
                return PTR_ERR(priv->base);

        /*
         * care platform info
         */
        memcpy(&priv->pfunc,
               &info->platform_callback,
               sizeof(struct renesas_usbhs_platform_callback));
        memcpy(&priv->dparam,
               &info->driver_param,
               sizeof(struct renesas_usbhs_driver_param));

        /* set driver callback functions for platform */
        dfunc                   = &info->driver_callback;
        dfunc->notify_hotplug   = usbhsc_drvcllbck_notify_hotplug;

        /* set default param if platform doesn't have */
        if (!priv->dparam.pipe_type) {
                priv->dparam.pipe_type = usbhsc_default_pipe_type;
                priv->dparam.pipe_size = ARRAY_SIZE(usbhsc_default_pipe_type);
        }
        if (!priv->dparam.pio_dma_border)
                priv->dparam.pio_dma_border = 64; /* 64byte */

        /* FIXME */
        /* runtime power control ? */
        if (priv->pfunc.get_vbus)
                usbhsc_flags_set(priv, USBHSF_RUNTIME_PWCTRL);

        /*
         * priv settings
         */
        priv->irq       = irq_res->start;
        if (irq_res->flags & IORESOURCE_IRQ_SHAREABLE)
                priv->irqflags = IRQF_SHARED;
        priv->pdev      = pdev;
        INIT_DELAYED_WORK(&priv->notify_hotplug_work, usbhsc_notify_hotplug);
        spin_lock_init(usbhs_priv_to_lock(priv));

        /* call pipe and module init */
        ret = usbhs_pipe_probe(priv);
        if (ret < 0)
                return ret;

        ret = usbhs_fifo_probe(priv);
        if (ret < 0)
                goto probe_end_pipe_exit;

        ret = usbhs_mod_probe(priv);
        if (ret < 0)
                goto probe_end_fifo_exit;

        /* dev_set_drvdata should be called after usbhs_mod_init */
        dev_set_drvdata(&pdev->dev, priv);

        /*
         * deviece reset here because
         * USB device might be used in boot loader.
         */
        usbhs_sys_clock_ctrl(priv, 0);

        /*
         * platform call
         *
         * USB phy setup might depend on CPU/Board.
         * If platform has its callback functions,
         * call it here.
         */
        ret = usbhs_platform_call(priv, hardware_init, pdev);
        if (ret < 0) {
                dev_err(&pdev->dev, "platform prove failed.\n");
                goto probe_end_mod_exit;
        }

        /* reset phy for connection */
        usbhs_platform_call(priv, phy_reset, pdev);

        /* power control */
        pm_runtime_enable(&pdev->dev);
        if (!usbhsc_flags_has(priv, USBHSF_RUNTIME_PWCTRL)) {
                usbhsc_power_ctrl(priv, 1);
                usbhs_mod_autonomy_mode(priv);
        }

        /*
         * manual call notify_hotplug for cold plug
         */
        ret = usbhsc_drvcllbck_notify_hotplug(pdev);
        if (ret < 0)
                goto probe_end_call_remove;

        dev_info(&pdev->dev, "probed\n");

        return ret;

probe_end_call_remove:
        usbhs_platform_call(priv, hardware_exit, pdev);
probe_end_mod_exit:
        usbhs_mod_remove(priv);
probe_end_fifo_exit:
        usbhs_fifo_remove(priv);
probe_end_pipe_exit:
        usbhs_pipe_remove(priv);

        dev_info(&pdev->dev, "probe failed\n");

        return ret;
}

static int usbhs_remove(struct platform_device *pdev)
{
        struct usbhs_priv *priv = usbhs_pdev_to_priv(pdev);
        struct renesas_usbhs_platform_info *info = pdev->dev.platform_data;
        struct renesas_usbhs_driver_callback *dfunc = &info->driver_callback;

        dev_dbg(&pdev->dev, "usb remove\n");

        dfunc->notify_hotplug = NULL;

        /* power off */
        if (!usbhsc_flags_has(priv, USBHSF_RUNTIME_PWCTRL))
                usbhsc_power_ctrl(priv, 0);

        pm_runtime_disable(&pdev->dev);

        usbhs_platform_call(priv, hardware_exit, pdev);
        usbhs_mod_remove(priv);
        usbhs_fifo_remove(priv);
        usbhs_pipe_remove(priv);

        return 0;
}

static int usbhsc_suspend(struct device *dev)
{
        struct usbhs_priv *priv = dev_get_drvdata(dev);
        struct usbhs_mod *mod = usbhs_mod_get_current(priv);

        if (mod) {
                usbhs_mod_call(priv, stop, priv);
                usbhs_mod_change(priv, -1);
        }

        if (mod || !usbhsc_flags_has(priv, USBHSF_RUNTIME_PWCTRL))
                usbhsc_power_ctrl(priv, 0);

        return 0;
}

static int usbhsc_resume(struct device *dev)
{
        struct usbhs_priv *priv = dev_get_drvdata(dev);
        struct platform_device *pdev = usbhs_priv_to_pdev(priv);

        if (!usbhsc_flags_has(priv, USBHSF_RUNTIME_PWCTRL))
                usbhsc_power_ctrl(priv, 1);

        usbhs_platform_call(priv, phy_reset, pdev);

        usbhsc_drvcllbck_notify_hotplug(pdev);

        return 0;
}

static int usbhsc_runtime_nop(struct device *dev)
{
        /* Runtime PM callback shared between ->runtime_suspend()
         * and ->runtime_resume(). Simply returns success.
         *
         * This driver re-initializes all registers after
         * pm_runtime_get_sync() anyway so there is no need
         * to save and restore registers here.
         */
        return 0;
}

static const struct dev_pm_ops usbhsc_pm_ops = {
        .suspend                = usbhsc_suspend,
        .resume                 = usbhsc_resume,
        .runtime_suspend        = usbhsc_runtime_nop,
        .runtime_resume         = usbhsc_runtime_nop,
};

static struct platform_driver renesas_usbhs_driver = {
        .driver         = {
                .name   = "renesas_usbhs",
                .pm     = &usbhsc_pm_ops,
        },
        .probe          = usbhs_probe,
        .remove         = usbhs_remove,
};

module_platform_driver(renesas_usbhs_driver);

MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("Renesas USB driver");
MODULE_AUTHOR("Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>");