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/err.h>
27 #include <linux/mfd/palmas.h>
28 #include <linux/of.h>
29 #include <linux/of_platform.h>
30 
31 static const char *palmas_extcon_cable[] = {
32 	[0] = "USB",
33 	[1] = "USB-HOST",
34 	NULL,
35 };
36 
37 static const int mutually_exclusive[] = {0x3, 0x0};
38 
39 static void palmas_usb_wakeup(struct palmas *palmas, int enable)
40 {
41 	if (enable)
42 		palmas_write(palmas, PALMAS_USB_OTG_BASE, PALMAS_USB_WAKEUP,
43 			PALMAS_USB_WAKEUP_ID_WK_UP_COMP);
44 	else
45 		palmas_write(palmas, PALMAS_USB_OTG_BASE, PALMAS_USB_WAKEUP, 0);
46 }
47 
48 static irqreturn_t palmas_vbus_irq_handler(int irq, void *_palmas_usb)
49 {
50 	struct palmas_usb *palmas_usb = _palmas_usb;
51 	unsigned int vbus_line_state;
52 
53 	palmas_read(palmas_usb->palmas, PALMAS_INTERRUPT_BASE,
54 		PALMAS_INT3_LINE_STATE, &vbus_line_state);
55 
56 	if (vbus_line_state & PALMAS_INT3_LINE_STATE_VBUS) {
57 		if (palmas_usb->linkstat != PALMAS_USB_STATE_VBUS) {
58 			palmas_usb->linkstat = PALMAS_USB_STATE_VBUS;
59 			extcon_set_cable_state(&palmas_usb->edev, "USB", true);
60 		} else {
61 			dev_dbg(palmas_usb->dev,
62 				"Spurious connect event detected\n");
63 		}
64 	} else if (!(vbus_line_state & PALMAS_INT3_LINE_STATE_VBUS)) {
65 		if (palmas_usb->linkstat == PALMAS_USB_STATE_VBUS) {
66 			palmas_usb->linkstat = PALMAS_USB_STATE_DISCONNECT;
67 			extcon_set_cable_state(&palmas_usb->edev, "USB", false);
68 		} else {
69 			dev_dbg(palmas_usb->dev,
70 				"Spurious disconnect event detected\n");
71 		}
72 	}
73 
74 	return IRQ_HANDLED;
75 }
76 
77 static irqreturn_t palmas_id_irq_handler(int irq, void *_palmas_usb)
78 {
79 	unsigned int set;
80 	struct palmas_usb *palmas_usb = _palmas_usb;
81 
82 	palmas_read(palmas_usb->palmas, PALMAS_USB_OTG_BASE,
83 		PALMAS_USB_ID_INT_LATCH_SET, &set);
84 
85 	if (set & PALMAS_USB_ID_INT_SRC_ID_GND) {
86 		palmas_write(palmas_usb->palmas, PALMAS_USB_OTG_BASE,
87 			PALMAS_USB_ID_INT_EN_HI_SET,
88 			PALMAS_USB_ID_INT_EN_HI_SET_ID_FLOAT);
89 		palmas_write(palmas_usb->palmas, PALMAS_USB_OTG_BASE,
90 			PALMAS_USB_ID_INT_EN_HI_CLR,
91 			PALMAS_USB_ID_INT_EN_HI_CLR_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 	} else if (set & PALMAS_USB_ID_INT_SRC_ID_FLOAT) {
98 		palmas_write(palmas_usb->palmas, PALMAS_USB_OTG_BASE,
99 			PALMAS_USB_ID_INT_EN_HI_SET,
100 			PALMAS_USB_ID_INT_EN_HI_SET_ID_GND);
101 		palmas_write(palmas_usb->palmas, PALMAS_USB_OTG_BASE,
102 			PALMAS_USB_ID_INT_EN_HI_CLR,
103 			PALMAS_USB_ID_INT_EN_HI_CLR_ID_FLOAT);
104 		palmas_write(palmas_usb->palmas, PALMAS_USB_OTG_BASE,
105 			PALMAS_USB_ID_INT_LATCH_CLR,
106 			PALMAS_USB_ID_INT_EN_HI_CLR_ID_FLOAT);
107 		palmas_usb->linkstat = PALMAS_USB_STATE_DISCONNECT;
108 		extcon_set_cable_state(&palmas_usb->edev, "USB-HOST", false);
109 	}
110 
111 	return IRQ_HANDLED;
112 }
113 
114 static void palmas_enable_irq(struct palmas_usb *palmas_usb)
115 {
116 	palmas_write(palmas_usb->palmas, PALMAS_USB_OTG_BASE,
117 		PALMAS_USB_VBUS_CTRL_SET,
118 		PALMAS_USB_VBUS_CTRL_SET_VBUS_ACT_COMP);
119 
120 	palmas_write(palmas_usb->palmas, PALMAS_USB_OTG_BASE,
121 		PALMAS_USB_ID_CTRL_SET, PALMAS_USB_ID_CTRL_SET_ID_ACT_COMP);
122 
123 	palmas_write(palmas_usb->palmas, PALMAS_USB_OTG_BASE,
124 		PALMAS_USB_ID_INT_EN_HI_SET,
125 		PALMAS_USB_ID_INT_EN_HI_SET_ID_GND);
126 
127 	palmas_vbus_irq_handler(palmas_usb->vbus_irq, palmas_usb);
128 
129 	/* cold plug for host mode needs this delay */
130 	msleep(30);
131 	palmas_id_irq_handler(palmas_usb->id_irq, palmas_usb);
132 }
133 
134 static int palmas_usb_probe(struct platform_device *pdev)
135 {
136 	struct palmas *palmas = dev_get_drvdata(pdev->dev.parent);
137 	struct palmas_usb_platform_data	*pdata = pdev->dev.platform_data;
138 	struct device_node *node = pdev->dev.of_node;
139 	struct palmas_usb *palmas_usb;
140 	int status;
141 
142 	if (node && !pdata) {
143 		pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
144 
145 		if (!pdata)
146 			return -ENOMEM;
147 
148 		pdata->wakeup = of_property_read_bool(node, "ti,wakeup");
149 	} else if (!pdata) {
150 		return -EINVAL;
151 	}
152 
153 	palmas_usb = devm_kzalloc(&pdev->dev, sizeof(*palmas_usb), GFP_KERNEL);
154 	if (!palmas_usb)
155 		return -ENOMEM;
156 
157 	palmas->usb = palmas_usb;
158 	palmas_usb->palmas = palmas;
159 
160 	palmas_usb->dev	 = &pdev->dev;
161 
162 	palmas_usb->id_otg_irq = regmap_irq_get_virq(palmas->irq_data,
163 						PALMAS_ID_OTG_IRQ);
164 	palmas_usb->id_irq = regmap_irq_get_virq(palmas->irq_data,
165 						PALMAS_ID_IRQ);
166 	palmas_usb->vbus_otg_irq = regmap_irq_get_virq(palmas->irq_data,
167 						PALMAS_VBUS_OTG_IRQ);
168 	palmas_usb->vbus_irq = regmap_irq_get_virq(palmas->irq_data,
169 						PALMAS_VBUS_IRQ);
170 
171 	palmas_usb_wakeup(palmas, pdata->wakeup);
172 
173 	platform_set_drvdata(pdev, palmas_usb);
174 
175 	palmas_usb->edev.name = "palmas-usb";
176 	palmas_usb->edev.supported_cable = palmas_extcon_cable;
177 	palmas_usb->edev.mutually_exclusive = mutually_exclusive;
178 
179 	status = extcon_dev_register(&palmas_usb->edev, palmas_usb->dev);
180 	if (status) {
181 		dev_err(&pdev->dev, "failed to register extcon device\n");
182 		return status;
183 	}
184 
185 	status = devm_request_threaded_irq(palmas_usb->dev, palmas_usb->id_irq,
186 			NULL, palmas_id_irq_handler,
187 			IRQF_TRIGGER_FALLING | IRQF_TRIGGER_RISING,
188 			"palmas_usb_id", palmas_usb);
189 	if (status < 0) {
190 		dev_err(&pdev->dev, "can't get IRQ %d, err %d\n",
191 					palmas_usb->id_irq, status);
192 		goto fail_extcon;
193 	}
194 
195 	status = devm_request_threaded_irq(palmas_usb->dev,
196 			palmas_usb->vbus_irq, NULL, palmas_vbus_irq_handler,
197 			IRQF_TRIGGER_FALLING | IRQF_TRIGGER_RISING,
198 			"palmas_usb_vbus", palmas_usb);
199 	if (status < 0) {
200 		dev_err(&pdev->dev, "can't get IRQ %d, err %d\n",
201 					palmas_usb->vbus_irq, status);
202 		goto fail_extcon;
203 	}
204 
205 	palmas_enable_irq(palmas_usb);
206 
207 	return 0;
208 
209 fail_extcon:
210 	extcon_dev_unregister(&palmas_usb->edev);
211 
212 	return status;
213 }
214 
215 static int palmas_usb_remove(struct platform_device *pdev)
216 {
217 	struct palmas_usb *palmas_usb = platform_get_drvdata(pdev);
218 
219 	extcon_dev_unregister(&palmas_usb->edev);
220 
221 	return 0;
222 }
223 
224 static struct of_device_id of_palmas_match_tbl[] = {
225 	{ .compatible = "ti,palmas-usb", },
226 	{ .compatible = "ti,twl6035-usb", },
227 	{ /* end */ }
228 };
229 
230 static struct platform_driver palmas_usb_driver = {
231 	.probe = palmas_usb_probe,
232 	.remove = palmas_usb_remove,
233 	.driver = {
234 		.name = "palmas-usb",
235 		.of_match_table = of_palmas_match_tbl,
236 		.owner = THIS_MODULE,
237 	},
238 };
239 
240 module_platform_driver(palmas_usb_driver);
241 
242 MODULE_ALIAS("platform:palmas-usb");
243 MODULE_AUTHOR("Graeme Gregory <gg@slimlogic.co.uk>");
244 MODULE_DESCRIPTION("Palmas USB transceiver driver");
245 MODULE_LICENSE("GPL");
246 MODULE_DEVICE_TABLE(of, of_palmas_match_tbl);
247