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