[linux-2.6-block.git] / drivers / usb / phy / phy-tahvo.c

// SPDX-License-Identifier: GPL-2.0
/*
 * Tahvo USB transceiver driver
 *
 * Copyright (C) 2005-2006 Nokia Corporation
 *
 * Parts copied from isp1301_omap.c.
 * Copyright (C) 2004 Texas Instruments
 * Copyright (C) 2004 David Brownell
 *
 * Original driver written by Juha Yrjölä, Tony Lindgren and Timo Teräs.
 * Modified for Retu/Tahvo MFD by Aaro Koskinen.
 */

#include <linux/io.h>
#include <linux/clk.h>
#include <linux/usb.h>
#include <linux/extcon-provider.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/usb/otg.h>
#include <linux/mfd/retu.h>
#include <linux/usb/gadget.h>
#include <linux/platform_device.h>

#define DRIVER_NAME     "tahvo-usb"

#define TAHVO_REG_IDSR	0x02
#define TAHVO_REG_USBR	0x06

#define USBR_SLAVE_CONTROL	(1 << 8)
#define USBR_VPPVIO_SW		(1 << 7)
#define USBR_SPEED		(1 << 6)
#define USBR_REGOUT		(1 << 5)
#define USBR_MASTER_SW2		(1 << 4)
#define USBR_MASTER_SW1		(1 << 3)
#define USBR_SLAVE_SW		(1 << 2)
#define USBR_NSUSPEND		(1 << 1)
#define USBR_SEMODE		(1 << 0)

#define TAHVO_MODE_HOST		0
#define TAHVO_MODE_PERIPHERAL	1

struct tahvo_usb {
	struct platform_device	*pt_dev;
	struct usb_phy		phy;
	int			vbus_state;
	struct mutex		serialize;
	struct clk		*ick;
	int			irq;
	int			tahvo_mode;
	struct extcon_dev	*extcon;
};

static const unsigned int tahvo_cable[] = {
	EXTCON_USB,
	EXTCON_USB_HOST,

	EXTCON_NONE,
};

static ssize_t vbus_show(struct device *device,
			       struct device_attribute *attr, char *buf)
{
	struct tahvo_usb *tu = dev_get_drvdata(device);
	return sprintf(buf, "%s\n", tu->vbus_state ? "on" : "off");
}
static DEVICE_ATTR_RO(vbus);

static void check_vbus_state(struct tahvo_usb *tu)
{
	struct retu_dev *rdev = dev_get_drvdata(tu->pt_dev->dev.parent);
	int reg, prev_state;

	reg = retu_read(rdev, TAHVO_REG_IDSR);
	if (reg & TAHVO_STAT_VBUS) {
		switch (tu->phy.otg->state) {
		case OTG_STATE_B_IDLE:
			/* Enable the gadget driver */
			if (tu->phy.otg->gadget)
				usb_gadget_vbus_connect(tu->phy.otg->gadget);
			tu->phy.otg->state = OTG_STATE_B_PERIPHERAL;
			usb_phy_set_event(&tu->phy, USB_EVENT_ENUMERATED);
			break;
		case OTG_STATE_A_IDLE:
			/*
			 * Session is now valid assuming the USB hub is driving
			 * Vbus.
			 */
			tu->phy.otg->state = OTG_STATE_A_HOST;
			break;
		default:
			break;
		}
		dev_info(&tu->pt_dev->dev, "USB cable connected\n");
	} else {
		switch (tu->phy.otg->state) {
		case OTG_STATE_B_PERIPHERAL:
			if (tu->phy.otg->gadget)
				usb_gadget_vbus_disconnect(tu->phy.otg->gadget);
			tu->phy.otg->state = OTG_STATE_B_IDLE;
			usb_phy_set_event(&tu->phy, USB_EVENT_NONE);
			break;
		case OTG_STATE_A_HOST:
			tu->phy.otg->state = OTG_STATE_A_IDLE;
			break;
		default:
			break;
		}
		dev_info(&tu->pt_dev->dev, "USB cable disconnected\n");
	}

	prev_state = tu->vbus_state;
	tu->vbus_state = reg & TAHVO_STAT_VBUS;
	if (prev_state != tu->vbus_state) {
		extcon_set_state_sync(tu->extcon, EXTCON_USB, tu->vbus_state);
		sysfs_notify(&tu->pt_dev->dev.kobj, NULL, "vbus_state");
	}
}

static void tahvo_usb_become_host(struct tahvo_usb *tu)
{
	struct retu_dev *rdev = dev_get_drvdata(tu->pt_dev->dev.parent);

	extcon_set_state_sync(tu->extcon, EXTCON_USB_HOST, true);

	/* Power up the transceiver in USB host mode */
	retu_write(rdev, TAHVO_REG_USBR, USBR_REGOUT | USBR_NSUSPEND |
		   USBR_MASTER_SW2 | USBR_MASTER_SW1);
	tu->phy.otg->state = OTG_STATE_A_IDLE;

	check_vbus_state(tu);
}

static void tahvo_usb_stop_host(struct tahvo_usb *tu)
{
	tu->phy.otg->state = OTG_STATE_A_IDLE;
}

static void tahvo_usb_become_peripheral(struct tahvo_usb *tu)
{
	struct retu_dev *rdev = dev_get_drvdata(tu->pt_dev->dev.parent);

	extcon_set_state_sync(tu->extcon, EXTCON_USB_HOST, false);

	/* Power up transceiver and set it in USB peripheral mode */
	retu_write(rdev, TAHVO_REG_USBR, USBR_SLAVE_CONTROL | USBR_REGOUT |
		   USBR_NSUSPEND | USBR_SLAVE_SW);
	tu->phy.otg->state = OTG_STATE_B_IDLE;

	check_vbus_state(tu);
}

static void tahvo_usb_stop_peripheral(struct tahvo_usb *tu)
{
	if (tu->phy.otg->gadget)
		usb_gadget_vbus_disconnect(tu->phy.otg->gadget);
	tu->phy.otg->state = OTG_STATE_B_IDLE;
}

static void tahvo_usb_power_off(struct tahvo_usb *tu)
{
	struct retu_dev *rdev = dev_get_drvdata(tu->pt_dev->dev.parent);

	/* Disable gadget controller if any */
	if (tu->phy.otg->gadget)
		usb_gadget_vbus_disconnect(tu->phy.otg->gadget);

	/* Power off transceiver */
	retu_write(rdev, TAHVO_REG_USBR, 0);
	tu->phy.otg->state = OTG_STATE_UNDEFINED;
}

static int tahvo_usb_set_suspend(struct usb_phy *dev, int suspend)
{
	struct tahvo_usb *tu = container_of(dev, struct tahvo_usb, phy);
	struct retu_dev *rdev = dev_get_drvdata(tu->pt_dev->dev.parent);
	u16 w;

	dev_dbg(&tu->pt_dev->dev, "%s\n", __func__);

	w = retu_read(rdev, TAHVO_REG_USBR);
	if (suspend)
		w &= ~USBR_NSUSPEND;
	else
		w |= USBR_NSUSPEND;
	retu_write(rdev, TAHVO_REG_USBR, w);

	return 0;
}

static int tahvo_usb_set_host(struct usb_otg *otg, struct usb_bus *host)
{
	struct tahvo_usb *tu = container_of(otg->usb_phy, struct tahvo_usb,
					    phy);

	mutex_lock(&tu->serialize);

	if (host == NULL) {
		if (tu->tahvo_mode == TAHVO_MODE_HOST)
			tahvo_usb_power_off(tu);
		otg->host = NULL;
		mutex_unlock(&tu->serialize);
		return 0;
	}

	if (tu->tahvo_mode == TAHVO_MODE_HOST) {
		otg->host = NULL;
		tahvo_usb_become_host(tu);
	}

	otg->host = host;

	mutex_unlock(&tu->serialize);

	return 0;
}

static int tahvo_usb_set_peripheral(struct usb_otg *otg,
				    struct usb_gadget *gadget)
{
	struct tahvo_usb *tu = container_of(otg->usb_phy, struct tahvo_usb,
					    phy);

	mutex_lock(&tu->serialize);

	if (!gadget) {
		if (tu->tahvo_mode == TAHVO_MODE_PERIPHERAL)
			tahvo_usb_power_off(tu);
		tu->phy.otg->gadget = NULL;
		mutex_unlock(&tu->serialize);
		return 0;
	}

	tu->phy.otg->gadget = gadget;
	if (tu->tahvo_mode == TAHVO_MODE_PERIPHERAL)
		tahvo_usb_become_peripheral(tu);

	mutex_unlock(&tu->serialize);

	return 0;
}

static irqreturn_t tahvo_usb_vbus_interrupt(int irq, void *_tu)
{
	struct tahvo_usb *tu = _tu;

	mutex_lock(&tu->serialize);
	check_vbus_state(tu);
	mutex_unlock(&tu->serialize);

	return IRQ_HANDLED;
}

static ssize_t otg_mode_show(struct device *device,
			     struct device_attribute *attr, char *buf)
{
	struct tahvo_usb *tu = dev_get_drvdata(device);

	switch (tu->tahvo_mode) {
	case TAHVO_MODE_HOST:
		return sprintf(buf, "host\n");
	case TAHVO_MODE_PERIPHERAL:
		return sprintf(buf, "peripheral\n");
	}

	return -EINVAL;
}

static ssize_t otg_mode_store(struct device *device,
			      struct device_attribute *attr,
			      const char *buf, size_t count)
{
	struct tahvo_usb *tu = dev_get_drvdata(device);
	int r;

	mutex_lock(&tu->serialize);
	if (count >= 4 && strncmp(buf, "host", 4) == 0) {
		if (tu->tahvo_mode == TAHVO_MODE_PERIPHERAL)
			tahvo_usb_stop_peripheral(tu);
		tu->tahvo_mode = TAHVO_MODE_HOST;
		if (tu->phy.otg->host) {
			dev_info(device, "HOST mode: host controller present\n");
			tahvo_usb_become_host(tu);
		} else {
			dev_info(device, "HOST mode: no host controller, powering off\n");
			tahvo_usb_power_off(tu);
		}
		r = strlen(buf);
	} else if (count >= 10 && strncmp(buf, "peripheral", 10) == 0) {
		if (tu->tahvo_mode == TAHVO_MODE_HOST)
			tahvo_usb_stop_host(tu);
		tu->tahvo_mode = TAHVO_MODE_PERIPHERAL;
		if (tu->phy.otg->gadget) {
			dev_info(device, "PERIPHERAL mode: gadget driver present\n");
			tahvo_usb_become_peripheral(tu);
		} else {
			dev_info(device, "PERIPHERAL mode: no gadget driver, powering off\n");
			tahvo_usb_power_off(tu);
		}
		r = strlen(buf);
	} else {
		r = -EINVAL;
	}
	mutex_unlock(&tu->serialize);

	return r;
}
static DEVICE_ATTR_RW(otg_mode);

static struct attribute *tahvo_attrs[] = {
	&dev_attr_vbus.attr,
	&dev_attr_otg_mode.attr,
	NULL
};
ATTRIBUTE_GROUPS(tahvo);

static int tahvo_usb_probe(struct platform_device *pdev)
{
	struct retu_dev *rdev = dev_get_drvdata(pdev->dev.parent);
	struct tahvo_usb *tu;
	int ret;

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

	tu->phy.otg = devm_kzalloc(&pdev->dev, sizeof(*tu->phy.otg),
				   GFP_KERNEL);
	if (!tu->phy.otg)
		return -ENOMEM;

	tu->pt_dev = pdev;

	/* Default mode */
#ifdef CONFIG_TAHVO_USB_HOST_BY_DEFAULT
	tu->tahvo_mode = TAHVO_MODE_HOST;
#else
	tu->tahvo_mode = TAHVO_MODE_PERIPHERAL;
#endif

	mutex_init(&tu->serialize);

	tu->ick = devm_clk_get(&pdev->dev, "usb_l4_ick");
	if (!IS_ERR(tu->ick))
		clk_enable(tu->ick);

	/*
	 * Set initial state, so that we generate kevents only on state changes.
	 */
	tu->vbus_state = retu_read(rdev, TAHVO_REG_IDSR) & TAHVO_STAT_VBUS;

	tu->extcon = devm_extcon_dev_allocate(&pdev->dev, tahvo_cable);
	if (IS_ERR(tu->extcon)) {
		dev_err(&pdev->dev, "failed to allocate memory for extcon\n");
		ret = PTR_ERR(tu->extcon);
		goto err_disable_clk;
	}

	ret = devm_extcon_dev_register(&pdev->dev, tu->extcon);
	if (ret) {
		dev_err(&pdev->dev, "could not register extcon device: %d\n",
			ret);
		goto err_disable_clk;
	}

	/* Set the initial cable state. */
	extcon_set_state_sync(tu->extcon, EXTCON_USB_HOST,
			       tu->tahvo_mode == TAHVO_MODE_HOST);
	extcon_set_state_sync(tu->extcon, EXTCON_USB, tu->vbus_state);

	/* Create OTG interface */
	tahvo_usb_power_off(tu);
	tu->phy.dev = &pdev->dev;
	tu->phy.otg->state = OTG_STATE_UNDEFINED;
	tu->phy.label = DRIVER_NAME;
	tu->phy.set_suspend = tahvo_usb_set_suspend;

	tu->phy.otg->usb_phy = &tu->phy;
	tu->phy.otg->set_host = tahvo_usb_set_host;
	tu->phy.otg->set_peripheral = tahvo_usb_set_peripheral;

	ret = usb_add_phy(&tu->phy, USB_PHY_TYPE_USB2);
	if (ret < 0) {
		dev_err(&pdev->dev, "cannot register USB transceiver: %d\n",
			ret);
		goto err_disable_clk;
	}

	dev_set_drvdata(&pdev->dev, tu);

	tu->irq = ret = platform_get_irq(pdev, 0);
	if (ret < 0)
		return ret;
	ret = request_threaded_irq(tu->irq, NULL, tahvo_usb_vbus_interrupt,
				   IRQF_ONESHOT,
				   "tahvo-vbus", tu);
	if (ret) {
		dev_err(&pdev->dev, "could not register tahvo-vbus irq: %d\n",
			ret);
		goto err_remove_phy;
	}

	return 0;

err_remove_phy:
	usb_remove_phy(&tu->phy);
err_disable_clk:
	if (!IS_ERR(tu->ick))
		clk_disable(tu->ick);

	return ret;
}

static int tahvo_usb_remove(struct platform_device *pdev)
{
	struct tahvo_usb *tu = platform_get_drvdata(pdev);

	free_irq(tu->irq, tu);
	usb_remove_phy(&tu->phy);
	if (!IS_ERR(tu->ick))
		clk_disable(tu->ick);

	return 0;
}

static struct platform_driver tahvo_usb_driver = {
	.probe		= tahvo_usb_probe,
	.remove		= tahvo_usb_remove,
	.driver		= {
		.name	= "tahvo-usb",
		.dev_groups = tahvo_groups,
	},
};
module_platform_driver(tahvo_usb_driver);

MODULE_DESCRIPTION("Tahvo USB transceiver driver");
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Juha Yrjölä, Tony Lindgren, and Timo Teräs");
MODULE_AUTHOR("Aaro Koskinen <aaro.koskinen@iki.fi>");
Commit	Line	Data
5fd54ace	1	// SPDX-License-Identifier: GPL-2.0
9ba96ae5 AK	2	/*
	3	* Tahvo USB transceiver driver
	4	*
	5	* Copyright (C) 2005-2006 Nokia Corporation
	6	*
	7	* Parts copied from isp1301_omap.c.
	8	* Copyright (C) 2004 Texas Instruments
	9	* Copyright (C) 2004 David Brownell
	10	*
	11	* Original driver written by Juha Yrjölä, Tony Lindgren and Timo Teräs.
	12	* Modified for Retu/Tahvo MFD by Aaro Koskinen.
9ba96ae5 AK	13	*/
	14
	15	#include <linux/io.h>
	16	#include <linux/clk.h>
	17	#include <linux/usb.h>
176aa360	18	#include <linux/extcon-provider.h>
9ba96ae5 AK	19	#include <linux/kernel.h>
	20	#include <linux/module.h>
	21	#include <linux/usb/otg.h>
	22	#include <linux/mfd/retu.h>
	23	#include <linux/usb/gadget.h>
	24	#include <linux/platform_device.h>
	25
	26	#define DRIVER_NAME "tahvo-usb"
	27
	28	#define TAHVO_REG_IDSR 0x02
	29	#define TAHVO_REG_USBR 0x06
	30
	31	#define USBR_SLAVE_CONTROL (1 << 8)
	32	#define USBR_VPPVIO_SW (1 << 7)
	33	#define USBR_SPEED (1 << 6)
	34	#define USBR_REGOUT (1 << 5)
	35	#define USBR_MASTER_SW2 (1 << 4)
	36	#define USBR_MASTER_SW1 (1 << 3)
	37	#define USBR_SLAVE_SW (1 << 2)
	38	#define USBR_NSUSPEND (1 << 1)
	39	#define USBR_SEMODE (1 << 0)
	40
	41	#define TAHVO_MODE_HOST 0
	42	#define TAHVO_MODE_PERIPHERAL 1
	43
	44	struct tahvo_usb {
	45	struct platform_device *pt_dev;
	46	struct usb_phy phy;
	47	int vbus_state;
	48	struct mutex serialize;
	49	struct clk *ick;
	50	int irq;
	51	int tahvo_mode;
860d2686	52	struct extcon_dev *extcon;
9ba96ae5 AK	53	};
9ba96ae5 AK	54
73b6ecdb	55	static const unsigned int tahvo_cable[] = {
2a9de9c0 CC	56	EXTCON_USB,
	57	EXTCON_USB_HOST,
	58
	59	EXTCON_NONE,
9ba96ae5 AK	60	};
9ba96ae5 AK	61
7f26ee4b	62	static ssize_t vbus_show(struct device *device,
9ba96ae5 AK	63	struct device_attribute attr, char buf)
	64	{
	65	struct tahvo_usb *tu = dev_get_drvdata(device);
	66	return sprintf(buf, "%s\n", tu->vbus_state ? "on" : "off");
	67	}
7f26ee4b	68	static DEVICE_ATTR_RO(vbus);
9ba96ae5 AK	69
	70	static void check_vbus_state(struct tahvo_usb *tu)
	71	{
	72	struct retu_dev *rdev = dev_get_drvdata(tu->pt_dev->dev.parent);
	73	int reg, prev_state;
	74
	75	reg = retu_read(rdev, TAHVO_REG_IDSR);
	76	if (reg & TAHVO_STAT_VBUS) {
e47d9254	77	switch (tu->phy.otg->state) {
9ba96ae5 AK	78	case OTG_STATE_B_IDLE:
	79	/* Enable the gadget driver */
	80	if (tu->phy.otg->gadget)
	81	usb_gadget_vbus_connect(tu->phy.otg->gadget);
e47d9254	82	tu->phy.otg->state = OTG_STATE_B_PERIPHERAL;
b20f3f9e	83	usb_phy_set_event(&tu->phy, USB_EVENT_ENUMERATED);
9ba96ae5 AK	84	break;
	85	case OTG_STATE_A_IDLE:
	86	/*
	87	* Session is now valid assuming the USB hub is driving
	88	* Vbus.
	89	*/
e47d9254	90	tu->phy.otg->state = OTG_STATE_A_HOST;
9ba96ae5 AK	91	break;
	92	default:
	93	break;
	94	}
	95	dev_info(&tu->pt_dev->dev, "USB cable connected\n");
	96	} else {
e47d9254	97	switch (tu->phy.otg->state) {
9ba96ae5 AK	98	case OTG_STATE_B_PERIPHERAL:
	99	if (tu->phy.otg->gadget)
	100	usb_gadget_vbus_disconnect(tu->phy.otg->gadget);
e47d9254	101	tu->phy.otg->state = OTG_STATE_B_IDLE;
b20f3f9e	102	usb_phy_set_event(&tu->phy, USB_EVENT_NONE);
9ba96ae5 AK	103	break;
9ba96ae5 AK	104	case OTG_STATE_A_HOST:
e47d9254	105	tu->phy.otg->state = OTG_STATE_A_IDLE;
9ba96ae5 AK	106	break;
	107	default:
	108	break;
	109	}
	110	dev_info(&tu->pt_dev->dev, "USB cable disconnected\n");
	111	}
	112
	113	prev_state = tu->vbus_state;
	114	tu->vbus_state = reg & TAHVO_STAT_VBUS;
	115	if (prev_state != tu->vbus_state) {
746c9085	116	extcon_set_state_sync(tu->extcon, EXTCON_USB, tu->vbus_state);
9ba96ae5 AK	117	sysfs_notify(&tu->pt_dev->dev.kobj, NULL, "vbus_state");
	118	}
	119	}
	120
	121	static void tahvo_usb_become_host(struct tahvo_usb *tu)
	122	{
	123	struct retu_dev *rdev = dev_get_drvdata(tu->pt_dev->dev.parent);
	124
746c9085	125	extcon_set_state_sync(tu->extcon, EXTCON_USB_HOST, true);
9ba96ae5 AK	126
	127	/* Power up the transceiver in USB host mode */
	128	retu_write(rdev, TAHVO_REG_USBR, USBR_REGOUT \| USBR_NSUSPEND \|
	129	USBR_MASTER_SW2 \| USBR_MASTER_SW1);
e47d9254	130	tu->phy.otg->state = OTG_STATE_A_IDLE;
9ba96ae5 AK	131
	132	check_vbus_state(tu);
	133	}
	134
	135	static void tahvo_usb_stop_host(struct tahvo_usb *tu)
	136	{
e47d9254	137	tu->phy.otg->state = OTG_STATE_A_IDLE;
9ba96ae5 AK	138	}
	139
	140	static void tahvo_usb_become_peripheral(struct tahvo_usb *tu)
	141	{
	142	struct retu_dev *rdev = dev_get_drvdata(tu->pt_dev->dev.parent);
	143
746c9085	144	extcon_set_state_sync(tu->extcon, EXTCON_USB_HOST, false);
9ba96ae5 AK	145
	146	/* Power up transceiver and set it in USB peripheral mode */
	147	retu_write(rdev, TAHVO_REG_USBR, USBR_SLAVE_CONTROL \| USBR_REGOUT \|
	148	USBR_NSUSPEND \| USBR_SLAVE_SW);
e47d9254	149	tu->phy.otg->state = OTG_STATE_B_IDLE;
9ba96ae5 AK	150
	151	check_vbus_state(tu);
	152	}
	153
	154	static void tahvo_usb_stop_peripheral(struct tahvo_usb *tu)
	155	{
	156	if (tu->phy.otg->gadget)
	157	usb_gadget_vbus_disconnect(tu->phy.otg->gadget);
e47d9254	158	tu->phy.otg->state = OTG_STATE_B_IDLE;
9ba96ae5 AK	159	}
	160
	161	static void tahvo_usb_power_off(struct tahvo_usb *tu)
	162	{
	163	struct retu_dev *rdev = dev_get_drvdata(tu->pt_dev->dev.parent);
	164
	165	/* Disable gadget controller if any */
	166	if (tu->phy.otg->gadget)
	167	usb_gadget_vbus_disconnect(tu->phy.otg->gadget);
	168
	169	/* Power off transceiver */
	170	retu_write(rdev, TAHVO_REG_USBR, 0);
e47d9254	171	tu->phy.otg->state = OTG_STATE_UNDEFINED;
9ba96ae5 AK	172	}
	173
	174	static int tahvo_usb_set_suspend(struct usb_phy *dev, int suspend)
	175	{
	176	struct tahvo_usb *tu = container_of(dev, struct tahvo_usb, phy);
	177	struct retu_dev *rdev = dev_get_drvdata(tu->pt_dev->dev.parent);
	178	u16 w;
	179
	180	dev_dbg(&tu->pt_dev->dev, "%s\n", __func__);
	181
	182	w = retu_read(rdev, TAHVO_REG_USBR);
	183	if (suspend)
	184	w &= ~USBR_NSUSPEND;
	185	else
	186	w \|= USBR_NSUSPEND;
	187	retu_write(rdev, TAHVO_REG_USBR, w);
	188
	189	return 0;
	190	}
	191
	192	static int tahvo_usb_set_host(struct usb_otg otg, struct usb_bus host)
	193	{
19c1eac2 AT	194	struct tahvo_usb *tu = container_of(otg->usb_phy, struct tahvo_usb,
19c1eac2 AT	195	phy);
9ba96ae5	196
9ba96ae5 AK	197	mutex_lock(&tu->serialize);
	198
	199	if (host == NULL) {
	200	if (tu->tahvo_mode == TAHVO_MODE_HOST)
	201	tahvo_usb_power_off(tu);
	202	otg->host = NULL;
	203	mutex_unlock(&tu->serialize);
	204	return 0;
	205	}
	206
	207	if (tu->tahvo_mode == TAHVO_MODE_HOST) {
	208	otg->host = NULL;
	209	tahvo_usb_become_host(tu);
	210	}
	211
	212	otg->host = host;
	213
	214	mutex_unlock(&tu->serialize);
	215
	216	return 0;
	217	}
	218
	219	static int tahvo_usb_set_peripheral(struct usb_otg *otg,
	220	struct usb_gadget *gadget)
	221	{
19c1eac2 AT	222	struct tahvo_usb *tu = container_of(otg->usb_phy, struct tahvo_usb,
19c1eac2 AT	223	phy);
9ba96ae5	224
9ba96ae5 AK	225	mutex_lock(&tu->serialize);
	226
	227	if (!gadget) {
	228	if (tu->tahvo_mode == TAHVO_MODE_PERIPHERAL)
	229	tahvo_usb_power_off(tu);
	230	tu->phy.otg->gadget = NULL;
	231	mutex_unlock(&tu->serialize);
	232	return 0;
	233	}
	234
	235	tu->phy.otg->gadget = gadget;
	236	if (tu->tahvo_mode == TAHVO_MODE_PERIPHERAL)
	237	tahvo_usb_become_peripheral(tu);
	238
	239	mutex_unlock(&tu->serialize);
	240
	241	return 0;
	242	}
	243
	244	static irqreturn_t tahvo_usb_vbus_interrupt(int irq, void *_tu)
	245	{
	246	struct tahvo_usb *tu = _tu;
	247
	248	mutex_lock(&tu->serialize);
	249	check_vbus_state(tu);
	250	mutex_unlock(&tu->serialize);
	251
	252	return IRQ_HANDLED;
	253	}
	254
	255	static ssize_t otg_mode_show(struct device *device,
	256	struct device_attribute attr, char buf)
	257	{
	258	struct tahvo_usb *tu = dev_get_drvdata(device);
	259
	260	switch (tu->tahvo_mode) {
	261	case TAHVO_MODE_HOST:
	262	return sprintf(buf, "host\n");
	263	case TAHVO_MODE_PERIPHERAL:
	264	return sprintf(buf, "peripheral\n");
	265	}
	266
	267	return -EINVAL;
	268	}
	269
	270	static ssize_t otg_mode_store(struct device *device,
	271	struct device_attribute *attr,
	272	const char *buf, size_t count)
	273	{
	274	struct tahvo_usb *tu = dev_get_drvdata(device);
	275	int r;
	276
	277	mutex_lock(&tu->serialize);
	278	if (count >= 4 && strncmp(buf, "host", 4) == 0) {
	279	if (tu->tahvo_mode == TAHVO_MODE_PERIPHERAL)
	280	tahvo_usb_stop_peripheral(tu);
	281	tu->tahvo_mode = TAHVO_MODE_HOST;
	282	if (tu->phy.otg->host) {
	283	dev_info(device, "HOST mode: host controller present\n");
	284	tahvo_usb_become_host(tu);
	285	} else {
	286	dev_info(device, "HOST mode: no host controller, powering off\n");
	287	tahvo_usb_power_off(tu);
	288	}
289	r = strlen(buf);
290	} else if (count >= 10 && strncmp(buf, "peripheral", 10) == 0) {
291	if (tu->tahvo_mode == TAHVO_MODE_HOST)
292	tahvo_usb_stop_host(tu);
293	tu->tahvo_mode = TAHVO_MODE_PERIPHERAL;
294	if (tu->phy.otg->gadget) {
295	dev_info(device, "PERIPHERAL mode: gadget driver present\n");
296	tahvo_usb_become_peripheral(tu);
297	} else {
298	dev_info(device, "PERIPHERAL mode: no gadget driver, powering off\n");
299	tahvo_usb_power_off(tu);
300	}
301	r = strlen(buf);
302	} else {
303	r = -EINVAL;
304	}
305	mutex_unlock(&tu->serialize);
306
307	return r;
308	}
ed5bd7a4	309	static DEVICE_ATTR_RW(otg_mode);
9ba96ae5	310
f4d09e9f	311	static struct attribute *tahvo_attrs[] = {
9ba96ae5 AK	312	&dev_attr_vbus.attr,
	313	&dev_attr_otg_mode.attr,
	314	NULL
	315	};
f4d09e9f	316	ATTRIBUTE_GROUPS(tahvo);
9ba96ae5 AK	317
	318	static int tahvo_usb_probe(struct platform_device *pdev)
	319	{
	320	struct retu_dev *rdev = dev_get_drvdata(pdev->dev.parent);
	321	struct tahvo_usb *tu;
	322	int ret;
	323
	324	tu = devm_kzalloc(&pdev->dev, sizeof(*tu), GFP_KERNEL);
	325	if (!tu)
	326	return -ENOMEM;
	327
	328	tu->phy.otg = devm_kzalloc(&pdev->dev, sizeof(*tu->phy.otg),
	329	GFP_KERNEL);
	330	if (!tu->phy.otg)
	331	return -ENOMEM;
	332
	333	tu->pt_dev = pdev;
	334
	335	/* Default mode */
	336	#ifdef CONFIG_TAHVO_USB_HOST_BY_DEFAULT
	337	tu->tahvo_mode = TAHVO_MODE_HOST;
	338	#else
	339	tu->tahvo_mode = TAHVO_MODE_PERIPHERAL;
	340	#endif
	341
	342	mutex_init(&tu->serialize);
	343
	344	tu->ick = devm_clk_get(&pdev->dev, "usb_l4_ick");
	345	if (!IS_ERR(tu->ick))
	346	clk_enable(tu->ick);
	347
	348	/*
	349	* Set initial state, so that we generate kevents only on state changes.
	350	*/
	351	tu->vbus_state = retu_read(rdev, TAHVO_REG_IDSR) & TAHVO_STAT_VBUS;
	352
860d2686 CC	353	tu->extcon = devm_extcon_dev_allocate(&pdev->dev, tahvo_cable);
	354	if (IS_ERR(tu->extcon)) {
	355	dev_err(&pdev->dev, "failed to allocate memory for extcon\n");
ce035409 AK	356	ret = PTR_ERR(tu->extcon);
ce035409 AK	357	goto err_disable_clk;
860d2686	358	}
9ba96ae5	359
860d2686	360	ret = devm_extcon_dev_register(&pdev->dev, tu->extcon);
9ba96ae5 AK	361	if (ret) {
	362	dev_err(&pdev->dev, "could not register extcon device: %d\n",
	363	ret);
	364	goto err_disable_clk;
	365	}
	366
	367	/* Set the initial cable state. */
746c9085	368	extcon_set_state_sync(tu->extcon, EXTCON_USB_HOST,
9ba96ae5	369	tu->tahvo_mode == TAHVO_MODE_HOST);
746c9085	370	extcon_set_state_sync(tu->extcon, EXTCON_USB, tu->vbus_state);
9ba96ae5 AK	371
	372	/* Create OTG interface */
	373	tahvo_usb_power_off(tu);
	374	tu->phy.dev = &pdev->dev;
e47d9254	375	tu->phy.otg->state = OTG_STATE_UNDEFINED;
9ba96ae5 AK	376	tu->phy.label = DRIVER_NAME;
	377	tu->phy.set_suspend = tahvo_usb_set_suspend;
	378
19c1eac2	379	tu->phy.otg->usb_phy = &tu->phy;
9ba96ae5 AK	380	tu->phy.otg->set_host = tahvo_usb_set_host;
	381	tu->phy.otg->set_peripheral = tahvo_usb_set_peripheral;
	382
	383	ret = usb_add_phy(&tu->phy, USB_PHY_TYPE_USB2);
	384	if (ret < 0) {
	385	dev_err(&pdev->dev, "cannot register USB transceiver: %d\n",
	386	ret);
860d2686	387	goto err_disable_clk;
9ba96ae5 AK	388	}
	389
	390	dev_set_drvdata(&pdev->dev, tu);
	391
0d45a137 SS	392	tu->irq = ret = platform_get_irq(pdev, 0);
	393	if (ret < 0)
	394	return ret;
a81df9ee FE	395	ret = request_threaded_irq(tu->irq, NULL, tahvo_usb_vbus_interrupt,
a81df9ee FE	396	IRQF_ONESHOT,
9ba96ae5 AK	397	"tahvo-vbus", tu);
	398	if (ret) {
	399	dev_err(&pdev->dev, "could not register tahvo-vbus irq: %d\n",
	400	ret);
	401	goto err_remove_phy;
	402	}
	403
9ba96ae5 AK	404	return 0;
9ba96ae5 AK	405
9ba96ae5 AK	406	err_remove_phy:
9ba96ae5 AK	407	usb_remove_phy(&tu->phy);
9ba96ae5 AK	408	err_disable_clk:
	409	if (!IS_ERR(tu->ick))
	410	clk_disable(tu->ick);
	411
	412	return ret;
	413	}
	414
	415	static int tahvo_usb_remove(struct platform_device *pdev)
	416	{
	417	struct tahvo_usb *tu = platform_get_drvdata(pdev);
	418
9ba96ae5 AK	419	free_irq(tu->irq, tu);
9ba96ae5 AK	420	usb_remove_phy(&tu->phy);
9ba96ae5 AK	421	if (!IS_ERR(tu->ick))
	422	clk_disable(tu->ick);
	423
	424	return 0;
	425	}
	426
	427	static struct platform_driver tahvo_usb_driver = {
	428	.probe = tahvo_usb_probe,
	429	.remove = tahvo_usb_remove,
	430	.driver = {
	431	.name = "tahvo-usb",
f4d09e9f	432	.dev_groups = tahvo_groups,
9ba96ae5 AK	433	},
	434	};
	435	module_platform_driver(tahvo_usb_driver);
	436
	437	MODULE_DESCRIPTION("Tahvo USB transceiver driver");
	438	MODULE_LICENSE("GPL");
	439	MODULE_AUTHOR("Juha Yrjölä, Tony Lindgren, and Timo Teräs");
	440	MODULE_AUTHOR("Aaro Koskinen <aaro.koskinen@iki.fi>");