1/*
2 * Palmas USB transceiver driver
3 *
4 * Copyright (C) 2013 Texas Instruments Incorporated - http://www.ti.com
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation; either version 2 of the License, or
8 * (at your option) any later version.
9 *
10 * Author: Graeme Gregory <gg@slimlogic.co.uk>
11 * Author: Kishon Vijay Abraham I <kishon@ti.com>
12 *
13 * Based on twl6030_usb.c
14 *
15 * Author: Hema HK <hemahk@ti.com>
16 *
17 * This program is distributed in the hope that it will be useful,
18 * but WITHOUT ANY WARRANTY; without even the implied warranty of
19 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
20 * GNU General Public License for more details.
21 */
22
23#include <linux/module.h>
24#include <linux/interrupt.h>
25#include <linux/platform_device.h>
26#include <linux/slab.h>
27#include <linux/err.h>
28#include <linux/mfd/palmas.h>
29#include <linux/of.h>
30#include <linux/of_platform.h>
31
32static const char *palmas_extcon_cable[] = {
33	[0] = "USB",
34	[1] = "USB-HOST",
35	NULL,
36};
37
38static const int mutually_exclusive[] = {0x3, 0x0};
39
40static void palmas_usb_wakeup(struct palmas *palmas, int enable)
41{
42	if (enable)
43		palmas_write(palmas, PALMAS_USB_OTG_BASE, PALMAS_USB_WAKEUP,
44			PALMAS_USB_WAKEUP_ID_WK_UP_COMP);
45	else
46		palmas_write(palmas, PALMAS_USB_OTG_BASE, PALMAS_USB_WAKEUP, 0);
47}
48
49static irqreturn_t palmas_vbus_irq_handler(int irq, void *_palmas_usb)
50{
51	struct palmas_usb *palmas_usb = _palmas_usb;
52	unsigned int vbus_line_state;
53
54	palmas_read(palmas_usb->palmas, PALMAS_INTERRUPT_BASE,
55		PALMAS_INT3_LINE_STATE, &vbus_line_state);
56
57	if (vbus_line_state & PALMAS_INT3_LINE_STATE_VBUS) {
58		if (palmas_usb->linkstat != PALMAS_USB_STATE_VBUS) {
59			palmas_usb->linkstat = PALMAS_USB_STATE_VBUS;
60			extcon_set_cable_state(palmas_usb->edev, "USB", true);
61			dev_info(palmas_usb->dev, "USB cable is attached\n");
62		} else {
63			dev_dbg(palmas_usb->dev,
64				"Spurious connect event detected\n");
65		}
66	} else if (!(vbus_line_state & PALMAS_INT3_LINE_STATE_VBUS)) {
67		if (palmas_usb->linkstat == PALMAS_USB_STATE_VBUS) {
68			palmas_usb->linkstat = PALMAS_USB_STATE_DISCONNECT;
69			extcon_set_cable_state(palmas_usb->edev, "USB", false);
70			dev_info(palmas_usb->dev, "USB cable is detached\n");
71		} else {
72			dev_dbg(palmas_usb->dev,
73				"Spurious disconnect event detected\n");
74		}
75	}
76
77	return IRQ_HANDLED;
78}
79
80static irqreturn_t palmas_id_irq_handler(int irq, void *_palmas_usb)
81{
82	unsigned int set, id_src;
83	struct palmas_usb *palmas_usb = _palmas_usb;
84
85	palmas_read(palmas_usb->palmas, PALMAS_USB_OTG_BASE,
86		PALMAS_USB_ID_INT_LATCH_SET, &set);
87	palmas_read(palmas_usb->palmas, PALMAS_USB_OTG_BASE,
88		PALMAS_USB_ID_INT_SRC, &id_src);
89
90	if ((set & PALMAS_USB_ID_INT_SRC_ID_GND) &&
91				(id_src & PALMAS_USB_ID_INT_SRC_ID_GND)) {
92		palmas_write(palmas_usb->palmas, PALMAS_USB_OTG_BASE,
93			PALMAS_USB_ID_INT_LATCH_CLR,
94			PALMAS_USB_ID_INT_EN_HI_CLR_ID_GND);
95		palmas_usb->linkstat = PALMAS_USB_STATE_ID;
96		extcon_set_cable_state(palmas_usb->edev, "USB-HOST", true);
97		dev_info(palmas_usb->dev, "USB-HOST cable is attached\n");
98	} else if ((set & PALMAS_USB_ID_INT_SRC_ID_FLOAT) &&
99				(id_src & PALMAS_USB_ID_INT_SRC_ID_FLOAT)) {
100		palmas_write(palmas_usb->palmas, PALMAS_USB_OTG_BASE,
101			PALMAS_USB_ID_INT_LATCH_CLR,
102			PALMAS_USB_ID_INT_EN_HI_CLR_ID_FLOAT);
103		palmas_usb->linkstat = PALMAS_USB_STATE_DISCONNECT;
104		extcon_set_cable_state(palmas_usb->edev, "USB-HOST", false);
105		dev_info(palmas_usb->dev, "USB-HOST cable is detached\n");
106	} else if ((palmas_usb->linkstat == PALMAS_USB_STATE_ID) &&
107				(!(set & PALMAS_USB_ID_INT_SRC_ID_GND))) {
108		palmas_usb->linkstat = PALMAS_USB_STATE_DISCONNECT;
109		extcon_set_cable_state(palmas_usb->edev, "USB-HOST", false);
110		dev_info(palmas_usb->dev, "USB-HOST cable is detached\n");
111	} else if ((palmas_usb->linkstat == PALMAS_USB_STATE_DISCONNECT) &&
112				(id_src & PALMAS_USB_ID_INT_SRC_ID_GND)) {
113		palmas_usb->linkstat = PALMAS_USB_STATE_ID;
114		extcon_set_cable_state(palmas_usb->edev, "USB-HOST", true);
115		dev_info(palmas_usb->dev, " USB-HOST cable is attached\n");
116	}
117
118	return IRQ_HANDLED;
119}
120
121static void palmas_enable_irq(struct palmas_usb *palmas_usb)
122{
123	palmas_write(palmas_usb->palmas, PALMAS_USB_OTG_BASE,
124		PALMAS_USB_VBUS_CTRL_SET,
125		PALMAS_USB_VBUS_CTRL_SET_VBUS_ACT_COMP);
126
127	palmas_write(palmas_usb->palmas, PALMAS_USB_OTG_BASE,
128		PALMAS_USB_ID_CTRL_SET, PALMAS_USB_ID_CTRL_SET_ID_ACT_COMP);
129
130	palmas_write(palmas_usb->palmas, PALMAS_USB_OTG_BASE,
131		PALMAS_USB_ID_INT_EN_HI_SET,
132		PALMAS_USB_ID_INT_EN_HI_SET_ID_GND |
133		PALMAS_USB_ID_INT_EN_HI_SET_ID_FLOAT);
134
135	if (palmas_usb->enable_vbus_detection)
136		palmas_vbus_irq_handler(palmas_usb->vbus_irq, palmas_usb);
137
138	/* cold plug for host mode needs this delay */
139	if (palmas_usb->enable_id_detection) {
140		msleep(30);
141		palmas_id_irq_handler(palmas_usb->id_irq, palmas_usb);
142	}
143}
144
145static int palmas_usb_probe(struct platform_device *pdev)
146{
147	struct palmas *palmas = dev_get_drvdata(pdev->dev.parent);
148	struct palmas_usb_platform_data	*pdata = dev_get_platdata(&pdev->dev);
149	struct device_node *node = pdev->dev.of_node;
150	struct palmas_usb *palmas_usb;
151	int status;
152
153	palmas_usb = devm_kzalloc(&pdev->dev, sizeof(*palmas_usb), GFP_KERNEL);
154	if (!palmas_usb)
155		return -ENOMEM;
156
157	if (node && !pdata) {
158		palmas_usb->wakeup = of_property_read_bool(node, "ti,wakeup");
159		palmas_usb->enable_id_detection = of_property_read_bool(node,
160						"ti,enable-id-detection");
161		palmas_usb->enable_vbus_detection = of_property_read_bool(node,
162						"ti,enable-vbus-detection");
163	} else {
164		palmas_usb->wakeup = true;
165		palmas_usb->enable_id_detection = true;
166		palmas_usb->enable_vbus_detection = true;
167
168		if (pdata)
169			palmas_usb->wakeup = pdata->wakeup;
170	}
171
172	palmas->usb = palmas_usb;
173	palmas_usb->palmas = palmas;
174
175	palmas_usb->dev	 = &pdev->dev;
176
177	palmas_usb->id_otg_irq = regmap_irq_get_virq(palmas->irq_data,
178						PALMAS_ID_OTG_IRQ);
179	palmas_usb->id_irq = regmap_irq_get_virq(palmas->irq_data,
180						PALMAS_ID_IRQ);
181	palmas_usb->vbus_otg_irq = regmap_irq_get_virq(palmas->irq_data,
182						PALMAS_VBUS_OTG_IRQ);
183	palmas_usb->vbus_irq = regmap_irq_get_virq(palmas->irq_data,
184						PALMAS_VBUS_IRQ);
185
186	palmas_usb_wakeup(palmas, palmas_usb->wakeup);
187
188	platform_set_drvdata(pdev, palmas_usb);
189
190	palmas_usb->edev = devm_extcon_dev_allocate(&pdev->dev,
191						    palmas_extcon_cable);
192	if (IS_ERR(palmas_usb->edev)) {
193		dev_err(&pdev->dev, "failed to allocate extcon device\n");
194		return -ENOMEM;
195	}
196	palmas_usb->edev->name = kstrdup(node->name, GFP_KERNEL);
197	palmas_usb->edev->mutually_exclusive = mutually_exclusive;
198
199	status = devm_extcon_dev_register(&pdev->dev, palmas_usb->edev);
200	if (status) {
201		dev_err(&pdev->dev, "failed to register extcon device\n");
202		kfree(palmas_usb->edev->name);
203		return status;
204	}
205
206	if (palmas_usb->enable_id_detection) {
207		status = devm_request_threaded_irq(palmas_usb->dev,
208				palmas_usb->id_irq,
209				NULL, palmas_id_irq_handler,
210				IRQF_TRIGGER_FALLING | IRQF_TRIGGER_RISING |
211				IRQF_ONESHOT | IRQF_EARLY_RESUME,
212				"palmas_usb_id", palmas_usb);
213		if (status < 0) {
214			dev_err(&pdev->dev, "can't get IRQ %d, err %d\n",
215					palmas_usb->id_irq, status);
216			kfree(palmas_usb->edev->name);
217			return status;
218		}
219	}
220
221	if (palmas_usb->enable_vbus_detection) {
222		status = devm_request_threaded_irq(palmas_usb->dev,
223				palmas_usb->vbus_irq, NULL,
224				palmas_vbus_irq_handler,
225				IRQF_TRIGGER_FALLING | IRQF_TRIGGER_RISING |
226				IRQF_ONESHOT | IRQF_EARLY_RESUME,
227				"palmas_usb_vbus", palmas_usb);
228		if (status < 0) {
229			dev_err(&pdev->dev, "can't get IRQ %d, err %d\n",
230					palmas_usb->vbus_irq, status);
231			kfree(palmas_usb->edev->name);
232			return status;
233		}
234	}
235
236	palmas_enable_irq(palmas_usb);
237	device_set_wakeup_capable(&pdev->dev, true);
238	return 0;
239}
240
241static int palmas_usb_remove(struct platform_device *pdev)
242{
243	struct palmas_usb *palmas_usb = platform_get_drvdata(pdev);
244
245	kfree(palmas_usb->edev->name);
246
247	return 0;
248}
249
250#ifdef CONFIG_PM_SLEEP
251static int palmas_usb_suspend(struct device *dev)
252{
253	struct palmas_usb *palmas_usb = dev_get_drvdata(dev);
254
255	if (device_may_wakeup(dev)) {
256		if (palmas_usb->enable_vbus_detection)
257			enable_irq_wake(palmas_usb->vbus_irq);
258		if (palmas_usb->enable_id_detection)
259			enable_irq_wake(palmas_usb->id_irq);
260	}
261	return 0;
262}
263
264static int palmas_usb_resume(struct device *dev)
265{
266	struct palmas_usb *palmas_usb = dev_get_drvdata(dev);
267
268	if (device_may_wakeup(dev)) {
269		if (palmas_usb->enable_vbus_detection)
270			disable_irq_wake(palmas_usb->vbus_irq);
271		if (palmas_usb->enable_id_detection)
272			disable_irq_wake(palmas_usb->id_irq);
273	}
274	return 0;
275};
276#endif
277
278static SIMPLE_DEV_PM_OPS(palmas_pm_ops, palmas_usb_suspend, palmas_usb_resume);
279
280static const struct of_device_id of_palmas_match_tbl[] = {
281	{ .compatible = "ti,palmas-usb", },
282	{ .compatible = "ti,palmas-usb-vid", },
283	{ .compatible = "ti,twl6035-usb", },
284	{ .compatible = "ti,twl6035-usb-vid", },
285	{ /* end */ }
286};
287
288static struct platform_driver palmas_usb_driver = {
289	.probe = palmas_usb_probe,
290	.remove = palmas_usb_remove,
291	.driver = {
292		.name = "palmas-usb",
293		.of_match_table = of_palmas_match_tbl,
294		.pm = &palmas_pm_ops,
295	},
296};
297
298module_platform_driver(palmas_usb_driver);
299
300MODULE_ALIAS("platform:palmas-usb");
301MODULE_AUTHOR("Graeme Gregory <gg@slimlogic.co.uk>");
302MODULE_DESCRIPTION("Palmas USB transceiver driver");
303MODULE_LICENSE("GPL");
304MODULE_DEVICE_TABLE(of, of_palmas_match_tbl);
305