xref: /openbmc/linux/drivers/misc/hisi_hikey_usb.c (revision da1d9caf)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Support for usb functionality of Hikey series boards
4  * based on Hisilicon Kirin Soc.
5  *
6  * Copyright (C) 2017-2018 Hilisicon Electronics Co., Ltd.
7  *		http://www.huawei.com
8  *
9  * Authors: Yu Chen <chenyu56@huawei.com>
10  */
11 
12 #include <linux/gpio/consumer.h>
13 #include <linux/kernel.h>
14 #include <linux/mod_devicetable.h>
15 #include <linux/module.h>
16 #include <linux/notifier.h>
17 #include <linux/of_gpio.h>
18 #include <linux/platform_device.h>
19 #include <linux/property.h>
20 #include <linux/regulator/consumer.h>
21 #include <linux/slab.h>
22 #include <linux/usb/role.h>
23 
24 #define DEVICE_DRIVER_NAME "hisi_hikey_usb"
25 
26 #define HUB_VBUS_POWER_ON 1
27 #define HUB_VBUS_POWER_OFF 0
28 #define USB_SWITCH_TO_HUB 1
29 #define USB_SWITCH_TO_TYPEC 0
30 #define TYPEC_VBUS_POWER_ON 1
31 #define TYPEC_VBUS_POWER_OFF 0
32 
33 struct hisi_hikey_usb {
34 	struct device *dev;
35 	struct gpio_desc *otg_switch;
36 	struct gpio_desc *typec_vbus;
37 	struct gpio_desc *reset;
38 
39 	struct regulator *regulator;
40 
41 	struct usb_role_switch *hub_role_sw;
42 
43 	struct usb_role_switch *dev_role_sw;
44 	enum usb_role role;
45 
46 	struct mutex lock;
47 	struct work_struct work;
48 
49 	struct notifier_block nb;
50 };
51 
52 static void hub_power_ctrl(struct hisi_hikey_usb *hisi_hikey_usb, int value)
53 {
54 	int ret, status;
55 
56 	if (!hisi_hikey_usb->regulator)
57 		return;
58 
59 	status = regulator_is_enabled(hisi_hikey_usb->regulator);
60 	if (status == !!value)
61 		return;
62 
63 	if (value)
64 		ret = regulator_enable(hisi_hikey_usb->regulator);
65 	else
66 		ret = regulator_disable(hisi_hikey_usb->regulator);
67 
68 	if (ret)
69 		dev_err(hisi_hikey_usb->dev,
70 			"Can't switch regulator state to %s\n",
71 			value ? "enabled" : "disabled");
72 }
73 
74 static void usb_switch_ctrl(struct hisi_hikey_usb *hisi_hikey_usb,
75 			    int switch_to)
76 {
77 	if (!hisi_hikey_usb->otg_switch)
78 		return;
79 
80 	gpiod_set_value_cansleep(hisi_hikey_usb->otg_switch, switch_to);
81 }
82 
83 static void usb_typec_power_ctrl(struct hisi_hikey_usb *hisi_hikey_usb,
84 				 int value)
85 {
86 	if (!hisi_hikey_usb->typec_vbus)
87 		return;
88 
89 	gpiod_set_value_cansleep(hisi_hikey_usb->typec_vbus, value);
90 }
91 
92 static void relay_set_role_switch(struct work_struct *work)
93 {
94 	struct hisi_hikey_usb *hisi_hikey_usb = container_of(work,
95 							struct hisi_hikey_usb,
96 							work);
97 	struct usb_role_switch *sw;
98 	enum usb_role role;
99 
100 	if (!hisi_hikey_usb || !hisi_hikey_usb->dev_role_sw)
101 		return;
102 
103 	mutex_lock(&hisi_hikey_usb->lock);
104 	switch (hisi_hikey_usb->role) {
105 	case USB_ROLE_NONE:
106 		usb_typec_power_ctrl(hisi_hikey_usb, TYPEC_VBUS_POWER_OFF);
107 		usb_switch_ctrl(hisi_hikey_usb, USB_SWITCH_TO_HUB);
108 		hub_power_ctrl(hisi_hikey_usb, HUB_VBUS_POWER_ON);
109 		break;
110 	case USB_ROLE_HOST:
111 		hub_power_ctrl(hisi_hikey_usb, HUB_VBUS_POWER_OFF);
112 		usb_switch_ctrl(hisi_hikey_usb, USB_SWITCH_TO_TYPEC);
113 		usb_typec_power_ctrl(hisi_hikey_usb, TYPEC_VBUS_POWER_ON);
114 		break;
115 	case USB_ROLE_DEVICE:
116 		hub_power_ctrl(hisi_hikey_usb, HUB_VBUS_POWER_OFF);
117 		usb_typec_power_ctrl(hisi_hikey_usb, TYPEC_VBUS_POWER_OFF);
118 		usb_switch_ctrl(hisi_hikey_usb, USB_SWITCH_TO_TYPEC);
119 		break;
120 	default:
121 		break;
122 	}
123 	sw = hisi_hikey_usb->dev_role_sw;
124 	role = hisi_hikey_usb->role;
125 	mutex_unlock(&hisi_hikey_usb->lock);
126 
127 	usb_role_switch_set_role(sw, role);
128 }
129 
130 static int hub_usb_role_switch_set(struct usb_role_switch *sw, enum usb_role role)
131 {
132 	struct hisi_hikey_usb *hisi_hikey_usb = usb_role_switch_get_drvdata(sw);
133 
134 	if (!hisi_hikey_usb || !hisi_hikey_usb->dev_role_sw)
135 		return -EINVAL;
136 
137 	mutex_lock(&hisi_hikey_usb->lock);
138 	hisi_hikey_usb->role = role;
139 	mutex_unlock(&hisi_hikey_usb->lock);
140 
141 	schedule_work(&hisi_hikey_usb->work);
142 
143 	return 0;
144 }
145 
146 static int hisi_hikey_usb_of_role_switch(struct platform_device *pdev,
147 					 struct hisi_hikey_usb *hisi_hikey_usb)
148 {
149 	struct device *dev = &pdev->dev;
150 	struct usb_role_switch_desc hub_role_switch = {NULL};
151 
152 	if (!device_property_read_bool(dev, "usb-role-switch"))
153 		return 0;
154 
155 	hisi_hikey_usb->otg_switch = devm_gpiod_get(dev, "otg-switch",
156 						    GPIOD_OUT_HIGH);
157 	if (IS_ERR(hisi_hikey_usb->otg_switch)) {
158 		dev_err(dev, "get otg-switch failed with error %ld\n",
159 			PTR_ERR(hisi_hikey_usb->otg_switch));
160 		return PTR_ERR(hisi_hikey_usb->otg_switch);
161 	}
162 
163 	hisi_hikey_usb->typec_vbus = devm_gpiod_get(dev, "typec-vbus",
164 						    GPIOD_OUT_LOW);
165 	if (IS_ERR(hisi_hikey_usb->typec_vbus)) {
166 		dev_err(dev, "get typec-vbus failed with error %ld\n",
167 			PTR_ERR(hisi_hikey_usb->typec_vbus));
168 		return PTR_ERR(hisi_hikey_usb->typec_vbus);
169 	}
170 
171 	hisi_hikey_usb->reset = devm_gpiod_get_optional(dev,
172 							"hub-reset-en",
173 							GPIOD_OUT_HIGH);
174 	if (IS_ERR(hisi_hikey_usb->reset)) {
175 		dev_err(dev, "get hub-reset-en failed with error %ld\n",
176 			PTR_ERR(hisi_hikey_usb->reset));
177 		return PTR_ERR(hisi_hikey_usb->reset);
178 	}
179 
180 	hisi_hikey_usb->dev_role_sw = usb_role_switch_get(dev);
181 	if (!hisi_hikey_usb->dev_role_sw)
182 		return -EPROBE_DEFER;
183 	if (IS_ERR(hisi_hikey_usb->dev_role_sw)) {
184 		dev_err(dev, "get device role switch failed with error %ld\n",
185 			PTR_ERR(hisi_hikey_usb->dev_role_sw));
186 		return PTR_ERR(hisi_hikey_usb->dev_role_sw);
187 	}
188 
189 	INIT_WORK(&hisi_hikey_usb->work, relay_set_role_switch);
190 
191 	hub_role_switch.fwnode = dev_fwnode(dev);
192 	hub_role_switch.set = hub_usb_role_switch_set;
193 	hub_role_switch.driver_data = hisi_hikey_usb;
194 
195 	hisi_hikey_usb->hub_role_sw = usb_role_switch_register(dev,
196 							       &hub_role_switch);
197 
198 	if (IS_ERR(hisi_hikey_usb->hub_role_sw)) {
199 		dev_err(dev,
200 			"failed to register hub role with error %ld\n",
201 			PTR_ERR(hisi_hikey_usb->hub_role_sw));
202 		usb_role_switch_put(hisi_hikey_usb->dev_role_sw);
203 		return PTR_ERR(hisi_hikey_usb->hub_role_sw);
204 	}
205 
206 	return 0;
207 }
208 
209 static int hisi_hikey_usb_probe(struct platform_device *pdev)
210 {
211 	struct device *dev = &pdev->dev;
212 	struct hisi_hikey_usb *hisi_hikey_usb;
213 	int ret;
214 
215 	hisi_hikey_usb = devm_kzalloc(dev, sizeof(*hisi_hikey_usb), GFP_KERNEL);
216 	if (!hisi_hikey_usb)
217 		return -ENOMEM;
218 
219 	hisi_hikey_usb->dev = &pdev->dev;
220 	mutex_init(&hisi_hikey_usb->lock);
221 
222 	hisi_hikey_usb->regulator = devm_regulator_get(dev, "hub-vdd");
223 	if (IS_ERR(hisi_hikey_usb->regulator)) {
224 		if (PTR_ERR(hisi_hikey_usb->regulator) == -EPROBE_DEFER) {
225 			dev_info(dev, "waiting for hub-vdd-supply\n");
226 			return PTR_ERR(hisi_hikey_usb->regulator);
227 		}
228 		dev_err(dev, "get hub-vdd-supply failed with error %ld\n",
229 			PTR_ERR(hisi_hikey_usb->regulator));
230 		return PTR_ERR(hisi_hikey_usb->regulator);
231 	}
232 
233 	ret = hisi_hikey_usb_of_role_switch(pdev, hisi_hikey_usb);
234 	if (ret)
235 		return ret;
236 
237 	platform_set_drvdata(pdev, hisi_hikey_usb);
238 
239 	return 0;
240 }
241 
242 static int  hisi_hikey_usb_remove(struct platform_device *pdev)
243 {
244 	struct hisi_hikey_usb *hisi_hikey_usb = platform_get_drvdata(pdev);
245 
246 	if (hisi_hikey_usb->hub_role_sw) {
247 		usb_role_switch_unregister(hisi_hikey_usb->hub_role_sw);
248 
249 		if (hisi_hikey_usb->dev_role_sw)
250 			usb_role_switch_put(hisi_hikey_usb->dev_role_sw);
251 	} else {
252 		hub_power_ctrl(hisi_hikey_usb, HUB_VBUS_POWER_OFF);
253 	}
254 
255 	return 0;
256 }
257 
258 static const struct of_device_id id_table_hisi_hikey_usb[] = {
259 	{ .compatible = "hisilicon,usbhub" },
260 	{}
261 };
262 MODULE_DEVICE_TABLE(of, id_table_hisi_hikey_usb);
263 
264 static struct platform_driver hisi_hikey_usb_driver = {
265 	.probe = hisi_hikey_usb_probe,
266 	.remove = hisi_hikey_usb_remove,
267 	.driver = {
268 		.name = DEVICE_DRIVER_NAME,
269 		.of_match_table = id_table_hisi_hikey_usb,
270 	},
271 };
272 
273 module_platform_driver(hisi_hikey_usb_driver);
274 
275 MODULE_AUTHOR("Yu Chen <chenyu56@huawei.com>");
276 MODULE_DESCRIPTION("Driver Support for USB functionality of Hikey");
277 MODULE_LICENSE("GPL v2");
278