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
33struct hisi_hikey_usb {
34	struct device *dev;
35	struct gpio_desc *otg_switch;
36	struct gpio_desc *typec_vbus;
37	struct gpio_desc *hub_vbus;
38	struct gpio_desc *reset;
39
40	struct regulator *regulator;
41
42	struct usb_role_switch *hub_role_sw;
43
44	struct usb_role_switch *dev_role_sw;
45	enum usb_role role;
46
47	struct mutex lock;
48	struct work_struct work;
49
50	struct notifier_block nb;
51};
52
53static void hub_power_ctrl(struct hisi_hikey_usb *hisi_hikey_usb, int value)
54{
55	int ret, status;
56
57	if (hisi_hikey_usb->hub_vbus)
58		gpiod_set_value_cansleep(hisi_hikey_usb->hub_vbus, value);
59
60	if (!hisi_hikey_usb->regulator)
61		return;
62
63	status = regulator_is_enabled(hisi_hikey_usb->regulator);
64	if (status == !!value)
65		return;
66
67	if (value)
68		ret = regulator_enable(hisi_hikey_usb->regulator);
69	else
70		ret = regulator_disable(hisi_hikey_usb->regulator);
71
72	if (ret)
73		dev_err(hisi_hikey_usb->dev,
74			"Can't switch regulator state to %s\n",
75			value ? "enabled" : "disabled");
76}
77
78static void usb_switch_ctrl(struct hisi_hikey_usb *hisi_hikey_usb,
79			    int switch_to)
80{
81	if (!hisi_hikey_usb->otg_switch)
82		return;
83
84	gpiod_set_value_cansleep(hisi_hikey_usb->otg_switch, switch_to);
85}
86
87static void usb_typec_power_ctrl(struct hisi_hikey_usb *hisi_hikey_usb,
88				 int value)
89{
90	if (!hisi_hikey_usb->typec_vbus)
91		return;
92
93	gpiod_set_value_cansleep(hisi_hikey_usb->typec_vbus, value);
94}
95
96static void relay_set_role_switch(struct work_struct *work)
97{
98	struct hisi_hikey_usb *hisi_hikey_usb = container_of(work,
99							struct hisi_hikey_usb,
100							work);
101	struct usb_role_switch *sw;
102	enum usb_role role;
103
104	if (!hisi_hikey_usb || !hisi_hikey_usb->dev_role_sw)
105		return;
106
107	mutex_lock(&hisi_hikey_usb->lock);
108	switch (hisi_hikey_usb->role) {
109	case USB_ROLE_NONE:
110		usb_typec_power_ctrl(hisi_hikey_usb, TYPEC_VBUS_POWER_OFF);
111		usb_switch_ctrl(hisi_hikey_usb, USB_SWITCH_TO_HUB);
112		hub_power_ctrl(hisi_hikey_usb, HUB_VBUS_POWER_ON);
113		break;
114	case USB_ROLE_HOST:
115		hub_power_ctrl(hisi_hikey_usb, HUB_VBUS_POWER_OFF);
116		usb_switch_ctrl(hisi_hikey_usb, USB_SWITCH_TO_TYPEC);
117		usb_typec_power_ctrl(hisi_hikey_usb, TYPEC_VBUS_POWER_ON);
118		break;
119	case USB_ROLE_DEVICE:
120		hub_power_ctrl(hisi_hikey_usb, HUB_VBUS_POWER_OFF);
121		usb_typec_power_ctrl(hisi_hikey_usb, TYPEC_VBUS_POWER_OFF);
122		usb_switch_ctrl(hisi_hikey_usb, USB_SWITCH_TO_TYPEC);
123		break;
124	default:
125		break;
126	}
127	sw = hisi_hikey_usb->dev_role_sw;
128	role = hisi_hikey_usb->role;
129	mutex_unlock(&hisi_hikey_usb->lock);
130
131	usb_role_switch_set_role(sw, role);
132}
133
134static int hub_usb_role_switch_set(struct usb_role_switch *sw, enum usb_role role)
135{
136	struct hisi_hikey_usb *hisi_hikey_usb = usb_role_switch_get_drvdata(sw);
137
138	if (!hisi_hikey_usb || !hisi_hikey_usb->dev_role_sw)
139		return -EINVAL;
140
141	mutex_lock(&hisi_hikey_usb->lock);
142	hisi_hikey_usb->role = role;
143	mutex_unlock(&hisi_hikey_usb->lock);
144
145	schedule_work(&hisi_hikey_usb->work);
146
147	return 0;
148}
149
150static int hisi_hikey_usb_parse_kirin970(struct platform_device *pdev,
151					 struct hisi_hikey_usb *hisi_hikey_usb)
152{
153	struct regulator *regulator;
154
155	regulator = devm_regulator_get(&pdev->dev, "hub-vdd");
156	if (IS_ERR(regulator)) {
157		if (PTR_ERR(regulator) == -EPROBE_DEFER) {
158			dev_info(&pdev->dev,
159				 "waiting for hub-vdd-supply to be probed\n");
160			return PTR_ERR(regulator);
161		}
162		dev_err(&pdev->dev,
163			"get hub-vdd-supply failed with error %ld\n",
164			PTR_ERR(regulator));
165		return PTR_ERR(regulator);
166	}
167	hisi_hikey_usb->regulator = regulator;
168
169	hisi_hikey_usb->reset = devm_gpiod_get(&pdev->dev, "hub_reset_en_gpio",
170					       GPIOD_OUT_HIGH);
171	if (IS_ERR(hisi_hikey_usb->reset))
172		return PTR_ERR(hisi_hikey_usb->reset);
173
174	return 0;
175}
176
177static int hisi_hikey_usb_probe(struct platform_device *pdev)
178{
179	struct device *dev = &pdev->dev;
180	struct hisi_hikey_usb *hisi_hikey_usb;
181	struct usb_role_switch_desc hub_role_switch = {NULL};
182	int ret;
183
184	hisi_hikey_usb = devm_kzalloc(dev, sizeof(*hisi_hikey_usb), GFP_KERNEL);
185	if (!hisi_hikey_usb)
186		return -ENOMEM;
187
188	hisi_hikey_usb->dev = &pdev->dev;
189
190	hisi_hikey_usb->otg_switch = devm_gpiod_get(dev, "otg-switch",
191						    GPIOD_OUT_HIGH);
192	if (IS_ERR(hisi_hikey_usb->otg_switch))
193		return PTR_ERR(hisi_hikey_usb->otg_switch);
194
195	hisi_hikey_usb->typec_vbus = devm_gpiod_get(dev, "typec-vbus",
196						    GPIOD_OUT_LOW);
197	if (IS_ERR(hisi_hikey_usb->typec_vbus))
198		return PTR_ERR(hisi_hikey_usb->typec_vbus);
199
200	/* Parse Kirin 970-specific OF data */
201	if (of_device_is_compatible(pdev->dev.of_node,
202				    "hisilicon,kirin970_hikey_usbhub")) {
203		ret = hisi_hikey_usb_parse_kirin970(pdev, hisi_hikey_usb);
204		if (ret)
205			return ret;
206	} else {
207		/* hub-vdd33-en is optional */
208		hisi_hikey_usb->hub_vbus = devm_gpiod_get_optional(dev, "hub-vdd33-en",
209								   GPIOD_OUT_HIGH);
210		if (IS_ERR(hisi_hikey_usb->hub_vbus))
211			return PTR_ERR(hisi_hikey_usb->hub_vbus);
212	}
213
214	hisi_hikey_usb->dev_role_sw = usb_role_switch_get(dev);
215	if (!hisi_hikey_usb->dev_role_sw)
216		return -EPROBE_DEFER;
217	if (IS_ERR(hisi_hikey_usb->dev_role_sw))
218		return PTR_ERR(hisi_hikey_usb->dev_role_sw);
219
220	INIT_WORK(&hisi_hikey_usb->work, relay_set_role_switch);
221	mutex_init(&hisi_hikey_usb->lock);
222
223	hub_role_switch.fwnode = dev_fwnode(dev);
224	hub_role_switch.set = hub_usb_role_switch_set;
225	hub_role_switch.driver_data = hisi_hikey_usb;
226
227	hisi_hikey_usb->hub_role_sw = usb_role_switch_register(dev,
228							       &hub_role_switch);
229
230	if (IS_ERR(hisi_hikey_usb->hub_role_sw)) {
231		usb_role_switch_put(hisi_hikey_usb->dev_role_sw);
232		return PTR_ERR(hisi_hikey_usb->hub_role_sw);
233	}
234
235	platform_set_drvdata(pdev, hisi_hikey_usb);
236
237	return 0;
238}
239
240static int  hisi_hikey_usb_remove(struct platform_device *pdev)
241{
242	struct hisi_hikey_usb *hisi_hikey_usb = platform_get_drvdata(pdev);
243
244	if (hisi_hikey_usb->hub_role_sw)
245		usb_role_switch_unregister(hisi_hikey_usb->hub_role_sw);
246
247	if (hisi_hikey_usb->dev_role_sw)
248		usb_role_switch_put(hisi_hikey_usb->dev_role_sw);
249
250	return 0;
251}
252
253static const struct of_device_id id_table_hisi_hikey_usb[] = {
254	{ .compatible = "hisilicon,gpio_hubv1" },
255	{ .compatible = "hisilicon,kirin970_hikey_usbhub" },
256	{}
257};
258MODULE_DEVICE_TABLE(of, id_table_hisi_hikey_usb);
259
260static struct platform_driver hisi_hikey_usb_driver = {
261	.probe = hisi_hikey_usb_probe,
262	.remove = hisi_hikey_usb_remove,
263	.driver = {
264		.name = DEVICE_DRIVER_NAME,
265		.of_match_table = id_table_hisi_hikey_usb,
266	},
267};
268
269module_platform_driver(hisi_hikey_usb_driver);
270
271MODULE_AUTHOR("Yu Chen <chenyu56@huawei.com>");
272MODULE_DESCRIPTION("Driver Support for USB functionality of Hikey");
273MODULE_LICENSE("GPL v2");
274