1/*
  2 * OMAP OTG controller driver
  3 *
  4 * Based on code from tahvo-usb.c and isp1301_omap.c drivers.
  5 *
  6 * Copyright (C) 2005-2006 Nokia Corporation
  7 * Copyright (C) 2004 Texas Instruments
  8 * Copyright (C) 2004 David Brownell
  9 *
 10 * This file is subject to the terms and conditions of the GNU General
 11 * Public License. See the file "COPYING" in the main directory of this
 12 * archive for more details.
 13 *
 14 * This program is distributed in the hope that it will be useful,
 15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 17 * GNU General Public License for more details.
 18 */
 19
 20#include <linux/io.h>
 21#include <linux/err.h>
 22#include <linux/extcon.h>
 23#include <linux/kernel.h>
 24#include <linux/module.h>
 25#include <linux/interrupt.h>
 26#include <linux/platform_device.h>
 27#include <linux/platform_data/usb-omap1.h>
 28
 29struct otg_device {
 30	void __iomem			*base;
 31	bool				id;
 32	bool				vbus;
 33	struct extcon_dev		*extcon;
 34	struct notifier_block		vbus_nb;
 35	struct notifier_block		id_nb;
 36};
 37
 38#define OMAP_OTG_CTRL		0x0c
 39#define OMAP_OTG_ASESSVLD	(1 << 20)
 40#define OMAP_OTG_BSESSEND	(1 << 19)
 41#define OMAP_OTG_BSESSVLD	(1 << 18)
 42#define OMAP_OTG_VBUSVLD	(1 << 17)
 43#define OMAP_OTG_ID		(1 << 16)
 44#define OMAP_OTG_XCEIV_OUTPUTS \
 45	(OMAP_OTG_ASESSVLD | OMAP_OTG_BSESSEND | OMAP_OTG_BSESSVLD | \
 46	 OMAP_OTG_VBUSVLD  | OMAP_OTG_ID)
 47
 48static void omap_otg_ctrl(struct otg_device *otg_dev, u32 outputs)
 49{
 50	u32 l;
 51
 52	l = readl(otg_dev->base + OMAP_OTG_CTRL);
 53	l &= ~OMAP_OTG_XCEIV_OUTPUTS;
 54	l |= outputs;
 55	writel(l, otg_dev->base + OMAP_OTG_CTRL);
 56}
 57
 58static void omap_otg_set_mode(struct otg_device *otg_dev)
 59{
 60	if (!otg_dev->id && otg_dev->vbus)
 61		/* Set B-session valid. */
 62		omap_otg_ctrl(otg_dev, OMAP_OTG_ID | OMAP_OTG_BSESSVLD);
 63	else if (otg_dev->vbus)
 64		/* Set A-session valid. */
 65		omap_otg_ctrl(otg_dev, OMAP_OTG_ASESSVLD);
 66	else if (!otg_dev->id)
 67		/* Set B-session end to indicate no VBUS. */
 68		omap_otg_ctrl(otg_dev, OMAP_OTG_ID | OMAP_OTG_BSESSEND);
 69}
 70
 71static int omap_otg_id_notifier(struct notifier_block *nb,
 72				unsigned long event, void *ptr)
 73{
 74	struct otg_device *otg_dev = container_of(nb, struct otg_device, id_nb);
 75
 76	otg_dev->id = event;
 77	omap_otg_set_mode(otg_dev);
 78
 79	return NOTIFY_DONE;
 80}
 81
 82static int omap_otg_vbus_notifier(struct notifier_block *nb,
 83				  unsigned long event, void *ptr)
 84{
 85	struct otg_device *otg_dev = container_of(nb, struct otg_device,
 86						  vbus_nb);
 87
 88	otg_dev->vbus = event;
 89	omap_otg_set_mode(otg_dev);
 90
 91	return NOTIFY_DONE;
 92}
 93
 94static int omap_otg_probe(struct platform_device *pdev)
 95{
 96	const struct omap_usb_config *config = pdev->dev.platform_data;
 97	struct otg_device *otg_dev;
 98	struct extcon_dev *extcon;
 99	int ret;
100	u32 rev;
101
102	if (!config || !config->extcon)
103		return -ENODEV;
104
105	extcon = extcon_get_extcon_dev(config->extcon);
106	if (!extcon)
107		return -EPROBE_DEFER;
108
109	otg_dev = devm_kzalloc(&pdev->dev, sizeof(*otg_dev), GFP_KERNEL);
110	if (!otg_dev)
111		return -ENOMEM;
112
113	otg_dev->base = devm_ioremap_resource(&pdev->dev, &pdev->resource[0]);
114	if (IS_ERR(otg_dev->base))
115		return PTR_ERR(otg_dev->base);
116
117	otg_dev->extcon = extcon;
118	otg_dev->id_nb.notifier_call = omap_otg_id_notifier;
119	otg_dev->vbus_nb.notifier_call = omap_otg_vbus_notifier;
120
121	ret = extcon_register_notifier(extcon, EXTCON_USB_HOST, &otg_dev->id_nb);
122	if (ret)
123		return ret;
124
125	ret = extcon_register_notifier(extcon, EXTCON_USB, &otg_dev->vbus_nb);
126	if (ret) {
127		extcon_unregister_notifier(extcon, EXTCON_USB_HOST,
128					&otg_dev->id_nb);
129		return ret;
130	}
131
132	otg_dev->id = extcon_get_cable_state_(extcon, EXTCON_USB_HOST);
133	otg_dev->vbus = extcon_get_cable_state_(extcon, EXTCON_USB);
134	omap_otg_set_mode(otg_dev);
135
136	rev = readl(otg_dev->base);
137
138	dev_info(&pdev->dev,
139		 "OMAP USB OTG controller rev %d.%d (%s, id=%d, vbus=%d)\n",
140		 (rev >> 4) & 0xf, rev & 0xf, config->extcon, otg_dev->id,
141		 otg_dev->vbus);
142
143	platform_set_drvdata(pdev, otg_dev);
144
145	return 0;
146}
147
148static int omap_otg_remove(struct platform_device *pdev)
149{
150	struct otg_device *otg_dev = platform_get_drvdata(pdev);
151	struct extcon_dev *edev = otg_dev->extcon;
152
153	extcon_unregister_notifier(edev, EXTCON_USB_HOST, &otg_dev->id_nb);
154	extcon_unregister_notifier(edev, EXTCON_USB, &otg_dev->vbus_nb);
155
156	return 0;
157}
158
159static struct platform_driver omap_otg_driver = {
160	.probe		= omap_otg_probe,
161	.remove		= omap_otg_remove,
162	.driver		= {
163		.name	= "omap_otg",
164	},
165};
166module_platform_driver(omap_otg_driver);
167
168MODULE_DESCRIPTION("OMAP USB OTG controller driver");
169MODULE_LICENSE("GPL");
170MODULE_AUTHOR("Aaro Koskinen <aaro.koskinen@iki.fi>");