usb: otg: add basic mxs phy driver support

* Freescale MXS USB Phy Device

Required properties:

- compatible: Should be "fsl,imx23-usbphy"

- reg: Should contain registers location and length

- interrupts: Should contain phy interrupt

Example:

usbphy1: usbphy@020c9000 {

	compatible = "fsl,imx6q-usbphy", "fsl,imx23-usbphy";

	reg = <0x020c9000 0x1000>;

	interrupts = <0 44 0x04>;

};

	help

	  Enable this to support Freescale USB OTG transceiver.

config USB_MXS_PHY

	tristate "Freescale MXS USB PHY support"

	depends on ARCH_MXC || ARCH_MXS

	select STMP_DEVICE

	select USB_OTG_UTILS

	help

	  Enable this to support the Freescale MXS USB PHY.

	  MXS Phy is used by some of the i.MX SoCs, for example imx23/28/6x.

config USB_MV_OTG

	tristate "Marvell USB OTG support"

	depends on USB_EHCI_MV && USB_MV_UDC && USB_SUSPEND

obj-$(CONFIG_AB8500_USB)	+= ab8500-usb.o

fsl_usb2_otg-objs		:= fsl_otg.o otg_fsm.o

obj-$(CONFIG_FSL_USB2_OTG)	+= fsl_usb2_otg.o

obj-$(CONFIG_USB_MXS_PHY)	+= mxs-phy.o

obj-$(CONFIG_USB_MV_OTG)	+= mv_otg.o

/*

 * Copyright 2012 Freescale Semiconductor, Inc.

 * Copyright (C) 2012 Marek Vasut <marex@denx.de>

 * on behalf of DENX Software Engineering GmbH

 *

 * The code contained herein is licensed under the GNU General Public

 * License. You may obtain a copy of the GNU General Public License

 * Version 2 or later at the following locations:

 *

 * http://www.opensource.org/licenses/gpl-license.html

 * http://www.gnu.org/copyleft/gpl.html

 */

#include <linux/module.h>

#include <linux/kernel.h>

#include <linux/platform_device.h>

#include <linux/clk.h>

#include <linux/usb/otg.h>

#include <linux/stmp_device.h>

#include <linux/delay.h>

#include <linux/err.h>

#include <linux/io.h>

#define DRIVER_NAME "mxs_phy"

#define HW_USBPHY_PWD				0x00

#define HW_USBPHY_CTRL				0x30

#define HW_USBPHY_CTRL_SET			0x34

#define HW_USBPHY_CTRL_CLR			0x38

#define BM_USBPHY_CTRL_SFTRST			BIT(31)

#define BM_USBPHY_CTRL_CLKGATE			BIT(30)

#define BM_USBPHY_CTRL_ENUTMILEVEL3		BIT(15)

#define BM_USBPHY_CTRL_ENUTMILEVEL2		BIT(14)

#define BM_USBPHY_CTRL_ENHOSTDISCONDETECT	BIT(1)

struct mxs_phy {

	struct usb_phy phy;

	struct clk *clk;

};

#define to_mxs_phy(p) container_of((p), struct mxs_phy, phy)

static void mxs_phy_hw_init(struct mxs_phy *mxs_phy)

{

	void __iomem *base = mxs_phy->phy.io_priv;

	stmp_reset_block(base + HW_USBPHY_CTRL);

	/* Power up the PHY */

	writel_relaxed(0, base + HW_USBPHY_PWD);

	/* enable FS/LS device */

	writel_relaxed(BM_USBPHY_CTRL_ENUTMILEVEL2 |

			BM_USBPHY_CTRL_ENUTMILEVEL3,

			base + HW_USBPHY_CTRL_SET);

}

static int mxs_phy_init(struct usb_phy *phy)

{

	struct mxs_phy *mxs_phy = to_mxs_phy(phy);

	clk_prepare_enable(mxs_phy->clk);

	mxs_phy_hw_init(mxs_phy);

	return 0;

}

static void mxs_phy_shutdown(struct usb_phy *phy)

{

	struct mxs_phy *mxs_phy = to_mxs_phy(phy);

	writel_relaxed(BM_USBPHY_CTRL_CLKGATE,

			phy->io_priv + HW_USBPHY_CTRL_SET);

	clk_disable_unprepare(mxs_phy->clk);

}

static int mxs_phy_on_connect(struct usb_phy *phy, int port)

{

	dev_dbg(phy->dev, "Connect on port %d\n", port);

	mxs_phy_hw_init(to_mxs_phy(phy));

	writel_relaxed(BM_USBPHY_CTRL_ENHOSTDISCONDETECT,

			phy->io_priv + HW_USBPHY_CTRL_SET);

	return 0;

}

static int mxs_phy_on_disconnect(struct usb_phy *phy, int port)

{

	dev_dbg(phy->dev, "Disconnect on port %d\n", port);

	writel_relaxed(BM_USBPHY_CTRL_ENHOSTDISCONDETECT,

			phy->io_priv + HW_USBPHY_CTRL_CLR);

	return 0;

}

static int mxs_phy_probe(struct platform_device *pdev)

{

	struct resource *res;

	void __iomem *base;

	struct clk *clk;

	struct mxs_phy *mxs_phy;

	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);

	if (!res) {

		dev_err(&pdev->dev, "can't get device resources\n");

		return -ENOENT;

	}

	base = devm_request_and_ioremap(&pdev->dev, res);

	if (!base)

		return -EBUSY;

	clk = devm_clk_get(&pdev->dev, NULL);

	if (IS_ERR(clk)) {

		dev_err(&pdev->dev,

			"can't get the clock, err=%ld", PTR_ERR(clk));

		return PTR_ERR(clk);

	}

	mxs_phy = devm_kzalloc(&pdev->dev, sizeof(*mxs_phy), GFP_KERNEL);

	if (!mxs_phy) {

		dev_err(&pdev->dev, "Failed to allocate USB PHY structure!\n");

		return -ENOMEM;

	}

	mxs_phy->phy.io_priv		= base;

	mxs_phy->phy.dev		= &pdev->dev;

	mxs_phy->phy.label		= DRIVER_NAME;

	mxs_phy->phy.init		= mxs_phy_init;

	mxs_phy->phy.shutdown		= mxs_phy_shutdown;

	mxs_phy->phy.notify_connect	= mxs_phy_on_connect;

	mxs_phy->phy.notify_disconnect	= mxs_phy_on_disconnect;

	ATOMIC_INIT_NOTIFIER_HEAD(&mxs_phy->phy.notifier);

	mxs_phy->clk = clk;

	platform_set_drvdata(pdev, &mxs_phy->phy);

	return 0;

}

static int __devexit mxs_phy_remove(struct platform_device *pdev)

{

	platform_set_drvdata(pdev, NULL);

	return 0;

}

static const struct of_device_id mxs_phy_dt_ids[] = {

	{ .compatible = "fsl,imx23-usbphy", },

	{ /* sentinel */ }

};

MODULE_DEVICE_TABLE(of, mxs_phy_dt_ids);

static struct platform_driver mxs_phy_driver = {

	.probe = mxs_phy_probe,

	.remove = __devexit_p(mxs_phy_remove),

	.driver = {

		.name = DRIVER_NAME,

		.owner	= THIS_MODULE,

		.of_match_table = mxs_phy_dt_ids,

	 },

};

static int __init mxs_phy_module_init(void)

{

	return platform_driver_register(&mxs_phy_driver);

}

postcore_initcall(mxs_phy_module_init);

static void __exit mxs_phy_module_exit(void)

{

	platform_driver_unregister(&mxs_phy_driver);

}

module_exit(mxs_phy_module_exit);

MODULE_ALIAS("platform:mxs-usb-phy");

MODULE_AUTHOR("Marek Vasut <marex@denx.de>");

MODULE_AUTHOR("Richard Zhao <richard.zhao@freescale.com>");

MODULE_DESCRIPTION("Freescale MXS USB PHY driver");

MODULE_LICENSE("GPL");