/*
 * Copyright (C) 2010 ST-Ericsson AB
 * Mian Yousaf Kaukab <mian.yousaf.kaukab@stericsson.com>
 *
 * Based on omap2430.c
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * 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., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/clk.h>
#include <linux/io.h>
#include <linux/platform_device.h>
#include <mach/usb.h>

#include "musb_core.h"

#define DEFAULT_DEVCTL 0x81
static void ux500_musb_set_vbus(struct musb *musb, int is_on);

struct ux500_glue {
	struct device		*dev;
	struct platform_device	*musb;
	struct clk		*clk;
};
#define glue_to_musb(g)	platform_get_drvdata(g->musb)

static struct timer_list notify_timer;
struct musb_context_registers context;
struct musb *_musb;
void ux500_store_context(struct musb *musb)
{
#ifdef CONFIG_PM
	int i;
	void __iomem *musb_base;
	void __iomem *epio;

	if (musb != NULL)
		_musb = musb;
	else
		return;

	musb_base = musb->mregs;

	if (is_host_enabled(musb)) {
		context.frame = musb_readw(musb_base, MUSB_FRAME);
		context.testmode = musb_readb(musb_base, MUSB_TESTMODE);
	}
	context.power = musb_readb(musb_base, MUSB_POWER);
	context.intrtxe = musb_readw(musb_base, MUSB_INTRTXE);
	context.intrrxe = musb_readw(musb_base, MUSB_INTRRXE);
	context.intrusbe = musb_readb(musb_base, MUSB_INTRUSBE);
	context.index = musb_readb(musb_base, MUSB_INDEX);
	context.devctl = DEFAULT_DEVCTL;
	for (i = 0; i < musb->config->num_eps; ++i) {
		epio = musb->endpoints[i].regs;
		context.index_regs[i].txmaxp =
				musb_readw(epio, MUSB_TXMAXP);
		context.index_regs[i].txcsr =
		musb_readw(epio, MUSB_TXCSR);
		context.index_regs[i].rxmaxp =
			musb_readw(epio, MUSB_RXMAXP);
		context.index_regs[i].rxcsr =
			musb_readw(epio, MUSB_RXCSR);

		if (musb->dyn_fifo) {
			context.index_regs[i].txfifoadd =
				musb_read_txfifoadd(musb_base);
			context.index_regs[i].rxfifoadd =
				musb_read_rxfifoadd(musb_base);
			context.index_regs[i].txfifosz =
				musb_read_txfifosz(musb_base);
			context.index_regs[i].rxfifosz =
				musb_read_rxfifosz(musb_base);
		}
		if (is_host_enabled(musb)) {
			context.index_regs[i].txtype =
				musb_readb(epio, MUSB_TXTYPE);
			context.index_regs[i].txinterval =
			musb_readb(epio, MUSB_TXINTERVAL);
			context.index_regs[i].rxtype =
				musb_readb(epio, MUSB_RXTYPE);
			context.index_regs[i].rxinterval =
				musb_readb(epio, MUSB_RXINTERVAL);

			context.index_regs[i].txfunaddr =
			musb_read_txfunaddr(musb_base, i);
			context.index_regs[i].txhubaddr =
				musb_read_txhubaddr(musb_base, i);
			context.index_regs[i].txhubport =
				musb_read_txhubport(musb_base, i);

			context.index_regs[i].rxfunaddr =
				musb_read_rxfunaddr(musb_base, i);
			context.index_regs[i].rxhubaddr =
				musb_read_rxhubaddr(musb_base, i);
			context.index_regs[i].rxhubport =
				musb_read_rxhubport(musb_base, i);
		}
	}
#endif
}
void ux500_restore_context(void)
{
#ifdef CONFIG_PM
	int i;
	struct musb *musb;
	void __iomem *musb_base;
	void __iomem *ep_target_regs;
	void __iomem *epio;

	if (_musb != NULL)
		musb = _musb;
	else
		return;

	musb_base = musb->mregs;
	if (is_host_enabled(musb)) {
		musb_writew(musb_base, MUSB_FRAME, context.frame);
		musb_writeb(musb_base, MUSB_TESTMODE, context.testmode);
	 }
	musb_writeb(musb_base, MUSB_POWER, context.power);
	musb_writew(musb_base, MUSB_INTRTXE, context.intrtxe);
	musb_writew(musb_base, MUSB_INTRRXE, context.intrrxe);
	musb_writeb(musb_base, MUSB_INTRUSBE, context.intrusbe);
	musb_writeb(musb_base, MUSB_DEVCTL, context.devctl);

	for (i = 0; i < musb->config->num_eps; ++i) {
		epio = musb->endpoints[i].regs;
		musb_writew(epio, MUSB_TXMAXP,
			context.index_regs[i].txmaxp);
		musb_writew(epio, MUSB_TXCSR,
			context.index_regs[i].txcsr);
		musb_writew(epio, MUSB_RXMAXP,
			context.index_regs[i].rxmaxp);
		musb_writew(epio, MUSB_RXCSR,
			context.index_regs[i].rxcsr);

	if (musb->dyn_fifo) {
		musb_write_txfifosz(musb_base,
			context.index_regs[i].txfifosz);
		musb_write_rxfifosz(musb_base,
			context.index_regs[i].rxfifosz);
		musb_write_txfifoadd(musb_base,
			context.index_regs[i].txfifoadd);
		musb_write_rxfifoadd(musb_base,
		context.index_regs[i].rxfifoadd);
		}

	if (is_host_enabled(musb)) {
		musb_writeb(epio, MUSB_TXTYPE,
			context.index_regs[i].txtype);
		musb_writeb(epio, MUSB_TXINTERVAL,
			context.index_regs[i].txinterval);
		musb_writeb(epio, MUSB_RXTYPE,
			context.index_regs[i].rxtype);
		musb_writeb(epio, MUSB_RXINTERVAL,

		musb->context.index_regs[i].rxinterval);
		musb_write_txfunaddr(musb_base, i,
			context.index_regs[i].txfunaddr);
		musb_write_txhubaddr(musb_base, i,
			context.index_regs[i].txhubaddr);
		musb_write_txhubport(musb_base, i,
			context.index_regs[i].txhubport);

		ep_target_regs =
			musb_read_target_reg_base(i, musb_base);

		musb_write_rxfunaddr(ep_target_regs,
				context.index_regs[i].rxfunaddr);
		musb_write_rxhubaddr(ep_target_regs,
			context.index_regs[i].rxhubaddr);
		musb_write_rxhubport(ep_target_regs,
		context.index_regs[i].rxhubport);
		}
	}
	musb_writeb(musb_base, MUSB_INDEX, context.index);
#endif
}

static void musb_notify_idle(unsigned long _musb)
{
	struct musb	*musb = (void *)_musb;
	unsigned long	flags;

	u8	devctl;

	spin_lock_irqsave(&musb->lock, flags);
	devctl = musb_readb(musb->mregs, MUSB_DEVCTL);

	switch (musb->xceiv->state) {
	case OTG_STATE_A_WAIT_BCON:
		devctl &= ~MUSB_DEVCTL_SESSION;
		musb_writeb(musb->mregs, MUSB_DEVCTL, devctl);
		musb->xceiv->state = OTG_STATE_B_IDLE;
		MUSB_DEV_MODE(musb);
		break;
	case OTG_STATE_A_SUSPEND:
	default:
		break;
	}
	spin_unlock_irqrestore(&musb->lock, flags);
}

/* blocking notifier support */
static int musb_otg_notifications(struct notifier_block *nb,
		unsigned long event, void *unused)
{
	struct musb	*musb = container_of(nb, struct musb, nb);

	switch (event) {
	case USB_EVENT_ID:
	case USB_EVENT_RIDA:
		dev_dbg(musb->controller, "ID GND\n");
		if (is_otg_enabled(musb)) {
				ux500_musb_set_vbus(musb, 1);
		}
		break;

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

		break;

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

		break;
	default:
		dev_dbg(musb->controller, "ID float\n");
		return NOTIFY_DONE;
	}
	return NOTIFY_OK;
}

static void ux500_musb_set_vbus(struct musb *musb, int is_on)
{
	u8		devctl;
	unsigned long timeout = jiffies + msecs_to_jiffies(1000);
	int ret = 1;
	/* HDRC controls CPEN, but beware current surges during device
	 * connect.  They can trigger transient overcurrent conditions
	 * that must be ignored.
	 */

	devctl = musb_readb(musb->mregs, MUSB_DEVCTL);

	if (is_on) {
		if (musb->xceiv->state == OTG_STATE_A_IDLE) {
			/* start the session */
			devctl |= MUSB_DEVCTL_SESSION;
			musb_writeb(musb->mregs, MUSB_DEVCTL, devctl);
			/*
			 * Wait for the musb to set as A device to enable the
			 * VBUS
			 */
			while (musb_readb(musb->mregs, MUSB_DEVCTL) & 0x80) {

				if (time_after(jiffies, timeout)) {
					dev_err(musb->controller,
					"configured as A device timeout");
					ret = -EINVAL;
					break;
				}
			}

		} else {
			musb->is_active = 1;
			musb->xceiv->default_a = 1;
			musb->xceiv->state = OTG_STATE_A_WAIT_VRISE;
			devctl |= MUSB_DEVCTL_SESSION;
			MUSB_HST_MODE(musb);
		}
	} else {
		musb->is_active = 0;

		/* NOTE:  we're skipping A_WAIT_VFALL -> A_IDLE and
		 * jumping right to B_IDLE...
		 */

		musb->xceiv->default_a = 0;
		musb->xceiv->state = OTG_STATE_B_IDLE;
		devctl &= ~MUSB_DEVCTL_SESSION;

		MUSB_DEV_MODE(musb);
	}
	musb_writeb(musb->mregs, MUSB_DEVCTL, devctl);

	dev_dbg(musb->controller, "VBUS %s, devctl %02x "
		/* otg %3x conf %08x prcm %08x */ "\n",
		otg_state_string(musb->xceiv->state),
		musb_readb(musb->mregs, MUSB_DEVCTL));
}

static void ux500_musb_try_idle(struct musb *musb, unsigned long timeout)
{
	static unsigned long	last_timer;

	if (timeout == 0)
		timeout = jiffies + msecs_to_jiffies(3);

	/* Never idle if active, or when VBUS timeout is not set as host */
	if (musb->is_active || ((musb->a_wait_bcon == 0)
			&& (musb->xceiv->state == OTG_STATE_A_WAIT_BCON))) {
		dev_dbg(musb->controller, "%s active, deleting timer\n",
			otg_state_string(musb->xceiv->state));
		del_timer(&notify_timer);
		last_timer = jiffies;
		return;
	}

	if (time_after(last_timer, timeout)) {
		if (!timer_pending(&notify_timer))
			last_timer = timeout;
		else {
			dev_dbg(musb->controller, "Longer idle timer "
						"already pending, ignoring\n");
			return;
		}
	}
	last_timer = timeout;

	dev_dbg(musb->controller, "%s inactive, for idle timer for %lu ms\n",
		otg_state_string(musb->xceiv->state),
		(unsigned long)jiffies_to_msecs(timeout - jiffies));
	mod_timer(&notify_timer, timeout);
}
static void ux500_musb_enable(struct musb *musb)
{
	ux500_store_context(musb);
}
static int ux500_musb_init(struct musb *musb)
{
	int status;
	musb->xceiv = otg_get_transceiver();
	if (!musb->xceiv) {
		pr_err("HS USB OTG: no transceiver configured\n");
		return -ENODEV;
	}

	musb->nb.notifier_call = musb_otg_notifications;
	status = otg_register_notifier(musb->xceiv, &musb->nb);

	if (status < 0) {
		dev_dbg(musb->controller, "notification register failed\n");
		goto err1;
	}

	setup_timer(&notify_timer, musb_notify_idle, (unsigned long) musb);

	return 0;
err1:
	return status;
}

/**
 * ux500_musb_exit() - unregister the platform USB driver.
 * @musb: struct musb pointer.
 *
 * This function unregisters the USB controller.
 */
static int ux500_musb_exit(struct musb *musb)
{
	otg_put_transceiver(musb->xceiv);

	return 0;
}

static const struct musb_platform_ops ux500_ops = {
	.init		= ux500_musb_init,
	.exit		= ux500_musb_exit,

	.set_vbus	= ux500_musb_set_vbus,
	.try_idle	= ux500_musb_try_idle,

	.enable		= ux500_musb_enable,
};

/**
 * ux500_probe() - Allocate the resources.
 * @pdev: struct platform_device.
 *
 * This function allocates the required memory for the
 * structures and initialize interrupts.
 */
static int __init ux500_probe(struct platform_device *pdev)
{
	struct musb_hdrc_platform_data	*pdata = pdev->dev.platform_data;
	struct platform_device		*musb;
	struct ux500_glue		*glue;
	struct clk			*clk;

	int				ret = -ENOMEM;

	glue = kzalloc(sizeof(*glue), GFP_KERNEL);
	if (!glue) {
		dev_err(&pdev->dev, "failed to allocate glue context\n");
		goto err0;
	}

	musb = platform_device_alloc("musb-hdrc", -1);
	if (!musb) {
		dev_err(&pdev->dev, "failed to allocate musb device\n");
		goto err1;
	}

	clk = clk_get(&pdev->dev, "usb");
	if (IS_ERR(clk)) {
		dev_err(&pdev->dev, "failed to get clock\n");
		ret = PTR_ERR(clk);
		goto err2;
	}

	ret = clk_enable(clk);
	if (ret) {
		dev_err(&pdev->dev, "failed to enable clock\n");
		goto err3;
	}

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

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

	pdata->platform_ops		= &ux500_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 err4;
	}

	ret = platform_device_add_data(musb, pdata, sizeof(*pdata));
	if (ret) {
		dev_err(&pdev->dev, "failed to add platform_data\n");
		goto err4;
	}

	ret = platform_device_add(musb);
	if (ret) {
		dev_err(&pdev->dev, "failed to register musb device\n");
		goto err4;
	}

	return 0;

err4:
	clk_disable(clk);

err3:
	clk_put(clk);

err2:
	platform_device_put(musb);

err1:
	kfree(glue);

err0:
	return ret;
}

static int __exit ux500_remove(struct platform_device *pdev)
{
	struct ux500_glue	*glue = platform_get_drvdata(pdev);

	platform_device_del(glue->musb);
	platform_device_put(glue->musb);
	clk_disable(glue->clk);
	clk_put(glue->clk);
	kfree(glue);

	return 0;
}

#ifdef CONFIG_PM
/**
 * ux500_suspend() - Handles the platform suspend.
 * @dev: struct device
 *
 * This function gets triggered when the platform
 * is going to suspend
 */
static int ux500_suspend(struct device *dev)
{
	struct ux500_glue	*glue = dev_get_drvdata(dev);
	struct musb		*musb = glue_to_musb(glue);

	otg_set_suspend(musb->xceiv, 1);
	clk_disable(glue->clk);

	return 0;
}

/**
 * ux500_resume() - Handles the platform resume.
 * @dev: struct device
 *
 * This function gets triggered when the platform
 * is going to resume
 */
static int ux500_resume(struct device *dev)
{
	struct ux500_glue	*glue = dev_get_drvdata(dev);
	struct musb		*musb = glue_to_musb(glue);
	int			ret;

	ret = clk_enable(glue->clk);
	if (ret) {
		dev_err(dev, "failed to enable clock\n");
		return ret;
	}

	otg_set_suspend(musb->xceiv, 0);

	return 0;
}

static const struct dev_pm_ops ux500_pm_ops = {
	.suspend	= ux500_suspend,
	.resume		= ux500_resume,
};

#define DEV_PM_OPS	(&ux500_pm_ops)
#else
#define DEV_PM_OPS	NULL
#endif

static struct platform_driver ux500_driver = {
	.remove		= __exit_p(ux500_remove),
	.driver		= {
		.name	= "musb-ux500",
		.pm	= DEV_PM_OPS,
	},
};

MODULE_DESCRIPTION("UX500 MUSB Glue Layer");
MODULE_AUTHOR("Mian Yousaf Kaukab <mian.yousaf.kaukab@stericsson.com>");
MODULE_LICENSE("GPL v2");

static int __init ux500_init(void)
{
	return platform_driver_probe(&ux500_driver, ux500_probe);
}
subsys_initcall(ux500_init);

static void __exit ux500_exit(void)
{
	platform_driver_unregister(&ux500_driver);
}
module_exit(ux500_exit);