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 
32 static const unsigned int palmas_extcon_cable[] = {
33 	EXTCON_USB,
34 	EXTCON_USB_HOST,
35 	EXTCON_NONE,
36 };
37 
38 static const int mutually_exclusive[] = {0x3, 0x0};
39 
40 static 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 
49 static irqreturn_t palmas_vbus_irq_handler(int irq, void *_palmas_usb)
50 {
51 	struct palmas_usb *palmas_usb = _palmas_usb;
52 	struct extcon_dev *edev = palmas_usb->edev;
53 	unsigned int vbus_line_state;
54 
55 	palmas_read(palmas_usb->palmas, PALMAS_INTERRUPT_BASE,
56 		PALMAS_INT3_LINE_STATE, &vbus_line_state);
57 
58 	if (vbus_line_state & PALMAS_INT3_LINE_STATE_VBUS) {
59 		if (palmas_usb->linkstat != PALMAS_USB_STATE_VBUS) {
60 			palmas_usb->linkstat = PALMAS_USB_STATE_VBUS;
61 			extcon_set_cable_state_(edev, EXTCON_USB, true);
62 			dev_info(palmas_usb->dev, "USB cable is attached\n");
63 		} else {
64 			dev_dbg(palmas_usb->dev,
65 				"Spurious connect event detected\n");
66 		}
67 	} else if (!(vbus_line_state & PALMAS_INT3_LINE_STATE_VBUS)) {
68 		if (palmas_usb->linkstat == PALMAS_USB_STATE_VBUS) {
69 			palmas_usb->linkstat = PALMAS_USB_STATE_DISCONNECT;
70 			extcon_set_cable_state_(edev, EXTCON_USB, false);
71 			dev_info(palmas_usb->dev, "USB cable is detached\n");
72 		} else {
73 			dev_dbg(palmas_usb->dev,
74 				"Spurious disconnect event detected\n");
75 		}
76 	}
77 
78 	return IRQ_HANDLED;
79 }
80 
81 static irqreturn_t palmas_id_irq_handler(int irq, void *_palmas_usb)
82 {
83 	unsigned int set, id_src;
84 	struct palmas_usb *palmas_usb = _palmas_usb;
85 	struct extcon_dev *edev = palmas_usb->edev;
86 
87 	palmas_read(palmas_usb->palmas, PALMAS_USB_OTG_BASE,
88 		PALMAS_USB_ID_INT_LATCH_SET, &set);
89 	palmas_read(palmas_usb->palmas, PALMAS_USB_OTG_BASE,
90 		PALMAS_USB_ID_INT_SRC, &id_src);
91 
92 	if ((set & PALMAS_USB_ID_INT_SRC_ID_GND) &&
93 				(id_src & PALMAS_USB_ID_INT_SRC_ID_GND)) {
94 		palmas_write(palmas_usb->palmas, PALMAS_USB_OTG_BASE,
95 			PALMAS_USB_ID_INT_LATCH_CLR,
96 			PALMAS_USB_ID_INT_EN_HI_CLR_ID_GND);
97 		palmas_usb->linkstat = PALMAS_USB_STATE_ID;
98 		extcon_set_cable_state_(edev, EXTCON_USB_HOST, true);
99 		dev_info(palmas_usb->dev, "USB-HOST cable is attached\n");
100 	} else if ((set & PALMAS_USB_ID_INT_SRC_ID_FLOAT) &&
101 				(id_src & PALMAS_USB_ID_INT_SRC_ID_FLOAT)) {
102 		palmas_write(palmas_usb->palmas, PALMAS_USB_OTG_BASE,
103 			PALMAS_USB_ID_INT_LATCH_CLR,
104 			PALMAS_USB_ID_INT_EN_HI_CLR_ID_FLOAT);
105 		palmas_usb->linkstat = PALMAS_USB_STATE_DISCONNECT;
106 		extcon_set_cable_state_(edev, EXTCON_USB_HOST, false);
107 		dev_info(palmas_usb->dev, "USB-HOST cable is detached\n");
108 	} else if ((palmas_usb->linkstat == PALMAS_USB_STATE_ID) &&
109 				(!(set & PALMAS_USB_ID_INT_SRC_ID_GND))) {
110 		palmas_usb->linkstat = PALMAS_USB_STATE_DISCONNECT;
111 		extcon_set_cable_state_(edev, EXTCON_USB_HOST, false);
112 		dev_info(palmas_usb->dev, "USB-HOST cable is detached\n");
113 	} else if ((palmas_usb->linkstat == PALMAS_USB_STATE_DISCONNECT) &&
114 				(id_src & PALMAS_USB_ID_INT_SRC_ID_GND)) {
115 		palmas_usb->linkstat = PALMAS_USB_STATE_ID;
116 		extcon_set_cable_state_(edev, EXTCON_USB_HOST, true);
117 		dev_info(palmas_usb->dev, " USB-HOST cable is attached\n");
118 	}
119 
120 	return IRQ_HANDLED;
121 }
122 
123 static void palmas_enable_irq(struct palmas_usb *palmas_usb)
124 {
125 	palmas_write(palmas_usb->palmas, PALMAS_USB_OTG_BASE,
126 		PALMAS_USB_VBUS_CTRL_SET,
127 		PALMAS_USB_VBUS_CTRL_SET_VBUS_ACT_COMP);
128 
129 	palmas_write(palmas_usb->palmas, PALMAS_USB_OTG_BASE,
130 		PALMAS_USB_ID_CTRL_SET, PALMAS_USB_ID_CTRL_SET_ID_ACT_COMP);
131 
132 	palmas_write(palmas_usb->palmas, PALMAS_USB_OTG_BASE,
133 		PALMAS_USB_ID_INT_EN_HI_SET,
134 		PALMAS_USB_ID_INT_EN_HI_SET_ID_GND |
135 		PALMAS_USB_ID_INT_EN_HI_SET_ID_FLOAT);
136 
137 	if (palmas_usb->enable_vbus_detection)
138 		palmas_vbus_irq_handler(palmas_usb->vbus_irq, palmas_usb);
139 
140 	/* cold plug for host mode needs this delay */
141 	if (palmas_usb->enable_id_detection) {
142 		msleep(30);
143 		palmas_id_irq_handler(palmas_usb->id_irq, palmas_usb);
144 	}
145 }
146 
147 static int palmas_usb_probe(struct platform_device *pdev)
148 {
149 	struct palmas *palmas = dev_get_drvdata(pdev->dev.parent);
150 	struct palmas_usb_platform_data	*pdata = dev_get_platdata(&pdev->dev);
151 	struct device_node *node = pdev->dev.of_node;
152 	struct palmas_usb *palmas_usb;
153 	int status;
154 
155 	palmas_usb = devm_kzalloc(&pdev->dev, sizeof(*palmas_usb), GFP_KERNEL);
156 	if (!palmas_usb)
157 		return -ENOMEM;
158 
159 	if (node && !pdata) {
160 		palmas_usb->wakeup = of_property_read_bool(node, "ti,wakeup");
161 		palmas_usb->enable_id_detection = of_property_read_bool(node,
162 						"ti,enable-id-detection");
163 		palmas_usb->enable_vbus_detection = of_property_read_bool(node,
164 						"ti,enable-vbus-detection");
165 	} else {
166 		palmas_usb->wakeup = true;
167 		palmas_usb->enable_id_detection = true;
168 		palmas_usb->enable_vbus_detection = true;
169 
170 		if (pdata)
171 			palmas_usb->wakeup = pdata->wakeup;
172 	}
173 
174 	palmas->usb = palmas_usb;
175 	palmas_usb->palmas = palmas;
176 
177 	palmas_usb->dev	 = &pdev->dev;
178 
179 	palmas_usb->id_otg_irq = regmap_irq_get_virq(palmas->irq_data,
180 						PALMAS_ID_OTG_IRQ);
181 	palmas_usb->id_irq = regmap_irq_get_virq(palmas->irq_data,
182 						PALMAS_ID_IRQ);
183 	palmas_usb->vbus_otg_irq = regmap_irq_get_virq(palmas->irq_data,
184 						PALMAS_VBUS_OTG_IRQ);
185 	palmas_usb->vbus_irq = regmap_irq_get_virq(palmas->irq_data,
186 						PALMAS_VBUS_IRQ);
187 
188 	palmas_usb_wakeup(palmas, palmas_usb->wakeup);
189 
190 	platform_set_drvdata(pdev, palmas_usb);
191 
192 	palmas_usb->edev = devm_extcon_dev_allocate(&pdev->dev,
193 						    palmas_extcon_cable);
194 	if (IS_ERR(palmas_usb->edev)) {
195 		dev_err(&pdev->dev, "failed to allocate extcon device\n");
196 		return -ENOMEM;
197 	}
198 	palmas_usb->edev->mutually_exclusive = mutually_exclusive;
199 
200 	status = devm_extcon_dev_register(&pdev->dev, palmas_usb->edev);
201 	if (status) {
202 		dev_err(&pdev->dev, "failed to register extcon device\n");
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 			return status;
217 		}
218 	}
219 
220 	if (palmas_usb->enable_vbus_detection) {
221 		status = devm_request_threaded_irq(palmas_usb->dev,
222 				palmas_usb->vbus_irq, NULL,
223 				palmas_vbus_irq_handler,
224 				IRQF_TRIGGER_FALLING | IRQF_TRIGGER_RISING |
225 				IRQF_ONESHOT | IRQF_EARLY_RESUME,
226 				"palmas_usb_vbus", palmas_usb);
227 		if (status < 0) {
228 			dev_err(&pdev->dev, "can't get IRQ %d, err %d\n",
229 					palmas_usb->vbus_irq, status);
230 			return status;
231 		}
232 	}
233 
234 	palmas_enable_irq(palmas_usb);
235 	device_set_wakeup_capable(&pdev->dev, true);
236 	return 0;
237 }
238 
239 #ifdef CONFIG_PM_SLEEP
240 static int palmas_usb_suspend(struct device *dev)
241 {
242 	struct palmas_usb *palmas_usb = dev_get_drvdata(dev);
243 
244 	if (device_may_wakeup(dev)) {
245 		if (palmas_usb->enable_vbus_detection)
246 			enable_irq_wake(palmas_usb->vbus_irq);
247 		if (palmas_usb->enable_id_detection)
248 			enable_irq_wake(palmas_usb->id_irq);
249 	}
250 	return 0;
251 }
252 
253 static int palmas_usb_resume(struct device *dev)
254 {
255 	struct palmas_usb *palmas_usb = dev_get_drvdata(dev);
256 
257 	if (device_may_wakeup(dev)) {
258 		if (palmas_usb->enable_vbus_detection)
259 			disable_irq_wake(palmas_usb->vbus_irq);
260 		if (palmas_usb->enable_id_detection)
261 			disable_irq_wake(palmas_usb->id_irq);
262 	}
263 	return 0;
264 };
265 #endif
266 
267 static SIMPLE_DEV_PM_OPS(palmas_pm_ops, palmas_usb_suspend, palmas_usb_resume);
268 
269 static const struct of_device_id of_palmas_match_tbl[] = {
270 	{ .compatible = "ti,palmas-usb", },
271 	{ .compatible = "ti,palmas-usb-vid", },
272 	{ .compatible = "ti,twl6035-usb", },
273 	{ .compatible = "ti,twl6035-usb-vid", },
274 	{ /* end */ }
275 };
276 
277 static struct platform_driver palmas_usb_driver = {
278 	.probe = palmas_usb_probe,
279 	.driver = {
280 		.name = "palmas-usb",
281 		.of_match_table = of_palmas_match_tbl,
282 		.pm = &palmas_pm_ops,
283 	},
284 };
285 
286 module_platform_driver(palmas_usb_driver);
287 
288 MODULE_ALIAS("platform:palmas-usb");
289 MODULE_AUTHOR("Graeme Gregory <gg@slimlogic.co.uk>");
290 MODULE_DESCRIPTION("Palmas USB transceiver driver");
291 MODULE_LICENSE("GPL");
292 MODULE_DEVICE_TABLE(of, of_palmas_match_tbl);
293