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12#include <linux/device.h>
13#include <linux/gpio/consumer.h>
14#include <linux/interrupt.h>
15#include <linux/irq.h>
16#include <linux/module.h>
17#include <linux/of.h>
18#include <linux/pinctrl/consumer.h>
19#include <linux/platform_device.h>
20#include <linux/regulator/consumer.h>
21#include <linux/usb/role.h>
22
23#define USB_GPIO_DEB_MS 20
24#define USB_GPIO_DEB_US ((USB_GPIO_DEB_MS) * 1000)
25
26#define USB_CONN_IRQF \
27 (IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING | IRQF_ONESHOT)
28
29struct usb_conn_info {
30 struct device *dev;
31 struct usb_role_switch *role_sw;
32 enum usb_role last_role;
33 struct regulator *vbus;
34 struct delayed_work dw_det;
35 unsigned long debounce_jiffies;
36
37 struct gpio_desc *id_gpiod;
38 struct gpio_desc *vbus_gpiod;
39 int id_irq;
40 int vbus_irq;
41};
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59
60static void usb_conn_detect_cable(struct work_struct *work)
61{
62 struct usb_conn_info *info;
63 enum usb_role role;
64 int id, vbus, ret;
65
66 info = container_of(to_delayed_work(work),
67 struct usb_conn_info, dw_det);
68
69
70 id = info->id_gpiod ?
71 gpiod_get_value_cansleep(info->id_gpiod) : 1;
72 vbus = info->vbus_gpiod ?
73 gpiod_get_value_cansleep(info->vbus_gpiod) : id;
74
75 if (!id)
76 role = USB_ROLE_HOST;
77 else if (vbus)
78 role = USB_ROLE_DEVICE;
79 else
80 role = USB_ROLE_NONE;
81
82 dev_dbg(info->dev, "role %d/%d, gpios: id %d, vbus %d\n",
83 info->last_role, role, id, vbus);
84
85 if (info->last_role == role) {
86 dev_warn(info->dev, "repeated role: %d\n", role);
87 return;
88 }
89
90 if (info->last_role == USB_ROLE_HOST)
91 regulator_disable(info->vbus);
92
93 ret = usb_role_switch_set_role(info->role_sw, role);
94 if (ret)
95 dev_err(info->dev, "failed to set role: %d\n", ret);
96
97 if (role == USB_ROLE_HOST) {
98 ret = regulator_enable(info->vbus);
99 if (ret)
100 dev_err(info->dev, "enable vbus regulator failed\n");
101 }
102
103 info->last_role = role;
104
105 dev_dbg(info->dev, "vbus regulator is %s\n",
106 regulator_is_enabled(info->vbus) ? "enabled" : "disabled");
107}
108
109static void usb_conn_queue_dwork(struct usb_conn_info *info,
110 unsigned long delay)
111{
112 queue_delayed_work(system_power_efficient_wq, &info->dw_det, delay);
113}
114
115static irqreturn_t usb_conn_isr(int irq, void *dev_id)
116{
117 struct usb_conn_info *info = dev_id;
118
119 usb_conn_queue_dwork(info, info->debounce_jiffies);
120
121 return IRQ_HANDLED;
122}
123
124static int usb_conn_probe(struct platform_device *pdev)
125{
126 struct device *dev = &pdev->dev;
127 struct usb_conn_info *info;
128 int ret = 0;
129
130 info = devm_kzalloc(dev, sizeof(*info), GFP_KERNEL);
131 if (!info)
132 return -ENOMEM;
133
134 info->dev = dev;
135 info->id_gpiod = devm_gpiod_get_optional(dev, "id", GPIOD_IN);
136 if (IS_ERR(info->id_gpiod))
137 return PTR_ERR(info->id_gpiod);
138
139 info->vbus_gpiod = devm_gpiod_get_optional(dev, "vbus", GPIOD_IN);
140 if (IS_ERR(info->vbus_gpiod))
141 return PTR_ERR(info->vbus_gpiod);
142
143 if (!info->id_gpiod && !info->vbus_gpiod) {
144 dev_err(dev, "failed to get gpios\n");
145 return -ENODEV;
146 }
147
148 if (info->id_gpiod)
149 ret = gpiod_set_debounce(info->id_gpiod, USB_GPIO_DEB_US);
150 if (!ret && info->vbus_gpiod)
151 ret = gpiod_set_debounce(info->vbus_gpiod, USB_GPIO_DEB_US);
152 if (ret < 0)
153 info->debounce_jiffies = msecs_to_jiffies(USB_GPIO_DEB_MS);
154
155 INIT_DELAYED_WORK(&info->dw_det, usb_conn_detect_cable);
156
157 info->vbus = devm_regulator_get(dev, "vbus");
158 if (IS_ERR(info->vbus)) {
159 if (PTR_ERR(info->vbus) != -EPROBE_DEFER)
160 dev_err(dev, "failed to get vbus\n");
161 return PTR_ERR(info->vbus);
162 }
163
164 info->role_sw = usb_role_switch_get(dev);
165 if (IS_ERR(info->role_sw)) {
166 if (PTR_ERR(info->role_sw) != -EPROBE_DEFER)
167 dev_err(dev, "failed to get role switch\n");
168
169 return PTR_ERR(info->role_sw);
170 }
171
172 if (info->id_gpiod) {
173 info->id_irq = gpiod_to_irq(info->id_gpiod);
174 if (info->id_irq < 0) {
175 dev_err(dev, "failed to get ID IRQ\n");
176 ret = info->id_irq;
177 goto put_role_sw;
178 }
179
180 ret = devm_request_threaded_irq(dev, info->id_irq, NULL,
181 usb_conn_isr, USB_CONN_IRQF,
182 pdev->name, info);
183 if (ret < 0) {
184 dev_err(dev, "failed to request ID IRQ\n");
185 goto put_role_sw;
186 }
187 }
188
189 if (info->vbus_gpiod) {
190 info->vbus_irq = gpiod_to_irq(info->vbus_gpiod);
191 if (info->vbus_irq < 0) {
192 dev_err(dev, "failed to get VBUS IRQ\n");
193 ret = info->vbus_irq;
194 goto put_role_sw;
195 }
196
197 ret = devm_request_threaded_irq(dev, info->vbus_irq, NULL,
198 usb_conn_isr, USB_CONN_IRQF,
199 pdev->name, info);
200 if (ret < 0) {
201 dev_err(dev, "failed to request VBUS IRQ\n");
202 goto put_role_sw;
203 }
204 }
205
206 platform_set_drvdata(pdev, info);
207
208
209 usb_conn_queue_dwork(info, 0);
210
211 return 0;
212
213put_role_sw:
214 usb_role_switch_put(info->role_sw);
215 return ret;
216}
217
218static int usb_conn_remove(struct platform_device *pdev)
219{
220 struct usb_conn_info *info = platform_get_drvdata(pdev);
221
222 cancel_delayed_work_sync(&info->dw_det);
223
224 if (info->last_role == USB_ROLE_HOST)
225 regulator_disable(info->vbus);
226
227 usb_role_switch_put(info->role_sw);
228
229 return 0;
230}
231
232static int __maybe_unused usb_conn_suspend(struct device *dev)
233{
234 struct usb_conn_info *info = dev_get_drvdata(dev);
235
236 if (info->id_gpiod)
237 disable_irq(info->id_irq);
238 if (info->vbus_gpiod)
239 disable_irq(info->vbus_irq);
240
241 pinctrl_pm_select_sleep_state(dev);
242
243 return 0;
244}
245
246static int __maybe_unused usb_conn_resume(struct device *dev)
247{
248 struct usb_conn_info *info = dev_get_drvdata(dev);
249
250 pinctrl_pm_select_default_state(dev);
251
252 if (info->id_gpiod)
253 enable_irq(info->id_irq);
254 if (info->vbus_gpiod)
255 enable_irq(info->vbus_irq);
256
257 usb_conn_queue_dwork(info, 0);
258
259 return 0;
260}
261
262static SIMPLE_DEV_PM_OPS(usb_conn_pm_ops,
263 usb_conn_suspend, usb_conn_resume);
264
265static const struct of_device_id usb_conn_dt_match[] = {
266 { .compatible = "gpio-usb-b-connector", },
267 { }
268};
269MODULE_DEVICE_TABLE(of, usb_conn_dt_match);
270
271static struct platform_driver usb_conn_driver = {
272 .probe = usb_conn_probe,
273 .remove = usb_conn_remove,
274 .driver = {
275 .name = "usb-conn-gpio",
276 .pm = &usb_conn_pm_ops,
277 .of_match_table = usb_conn_dt_match,
278 },
279};
280
281module_platform_driver(usb_conn_driver);
282
283MODULE_AUTHOR("Chunfeng Yun <chunfeng.yun@mediatek.com>");
284MODULE_DESCRIPTION("USB GPIO based connection detection driver");
285MODULE_LICENSE("GPL v2");
286
