1 // SPDX-License-Identifier: GPL-2.0+
2 //
3 // extcon-ptn5150.c - PTN5150 CC logic extcon driver to support USB detection
4 //
5 // Based on extcon-sm5502.c driver
6 // Copyright (c) 2018-2019 by Vijai Kumar K
7 // Author: Vijai Kumar K <vijaikumar.kanagarajan@gmail.com>
8 // Copyright (c) 2020 Krzysztof Kozlowski <krzk@kernel.org>
9 
10 #include <linux/bitfield.h>
11 #include <linux/err.h>
12 #include <linux/i2c.h>
13 #include <linux/interrupt.h>
14 #include <linux/kernel.h>
15 #include <linux/module.h>
16 #include <linux/regmap.h>
17 #include <linux/slab.h>
18 #include <linux/extcon-provider.h>
19 #include <linux/gpio/consumer.h>
20 #include <linux/usb/role.h>
21 
22 /* PTN5150 registers */
23 #define PTN5150_REG_DEVICE_ID			0x01
24 #define PTN5150_REG_CONTROL			0x02
25 #define PTN5150_REG_INT_STATUS			0x03
26 #define PTN5150_REG_CC_STATUS			0x04
27 #define PTN5150_REG_CON_DET			0x09
28 #define PTN5150_REG_VCONN_STATUS		0x0a
29 #define PTN5150_REG_RESET			0x0b
30 #define PTN5150_REG_INT_MASK			0x18
31 #define PTN5150_REG_INT_REG_STATUS		0x19
32 #define PTN5150_REG_END				PTN5150_REG_INT_REG_STATUS
33 
34 #define PTN5150_DFP_ATTACHED			0x1
35 #define PTN5150_UFP_ATTACHED			0x2
36 
37 /* Define PTN5150 MASK/SHIFT constant */
38 #define PTN5150_REG_DEVICE_ID_VERSION		GENMASK(7, 3)
39 #define PTN5150_REG_DEVICE_ID_VENDOR		GENMASK(2, 0)
40 
41 #define PTN5150_REG_CC_PORT_ATTACHMENT		GENMASK(4, 2)
42 #define PTN5150_REG_CC_VBUS_DETECTION		BIT(7)
43 #define PTN5150_REG_INT_CABLE_ATTACH_MASK	BIT(0)
44 #define PTN5150_REG_INT_CABLE_DETACH_MASK	BIT(1)
45 
46 struct ptn5150_info {
47 	struct device *dev;
48 	struct extcon_dev *edev;
49 	struct i2c_client *i2c;
50 	struct regmap *regmap;
51 	struct gpio_desc *int_gpiod;
52 	struct gpio_desc *vbus_gpiod;
53 	int irq;
54 	struct work_struct irq_work;
55 	struct mutex mutex;
56 	struct usb_role_switch *role_sw;
57 };
58 
59 /* List of detectable cables */
60 static const unsigned int ptn5150_extcon_cable[] = {
61 	EXTCON_USB,
62 	EXTCON_USB_HOST,
63 	EXTCON_NONE,
64 };
65 
66 static const struct regmap_config ptn5150_regmap_config = {
67 	.reg_bits	= 8,
68 	.val_bits	= 8,
69 	.max_register	= PTN5150_REG_END,
70 };
71 
ptn5150_check_state(struct ptn5150_info * info)72 static void ptn5150_check_state(struct ptn5150_info *info)
73 {
74 	unsigned int port_status, reg_data, vbus;
75 	enum usb_role usb_role = USB_ROLE_NONE;
76 	int ret;
77 
78 	ret = regmap_read(info->regmap, PTN5150_REG_CC_STATUS, &reg_data);
79 	if (ret) {
80 		dev_err(info->dev, "failed to read CC STATUS %d\n", ret);
81 		return;
82 	}
83 
84 	port_status = FIELD_GET(PTN5150_REG_CC_PORT_ATTACHMENT, reg_data);
85 
86 	switch (port_status) {
87 	case PTN5150_DFP_ATTACHED:
88 		extcon_set_state_sync(info->edev, EXTCON_USB_HOST, false);
89 		gpiod_set_value_cansleep(info->vbus_gpiod, 0);
90 		extcon_set_state_sync(info->edev, EXTCON_USB, true);
91 		usb_role = USB_ROLE_DEVICE;
92 		break;
93 	case PTN5150_UFP_ATTACHED:
94 		extcon_set_state_sync(info->edev, EXTCON_USB, false);
95 		vbus = FIELD_GET(PTN5150_REG_CC_VBUS_DETECTION, reg_data);
96 		if (vbus)
97 			gpiod_set_value_cansleep(info->vbus_gpiod, 0);
98 		else
99 			gpiod_set_value_cansleep(info->vbus_gpiod, 1);
100 
101 		extcon_set_state_sync(info->edev, EXTCON_USB_HOST, true);
102 		usb_role = USB_ROLE_HOST;
103 		break;
104 	default:
105 		break;
106 	}
107 
108 	if (usb_role) {
109 		ret = usb_role_switch_set_role(info->role_sw, usb_role);
110 		if (ret)
111 			dev_err(info->dev, "failed to set %s role: %d\n",
112 				usb_role_string(usb_role), ret);
113 	}
114 }
115 
ptn5150_irq_work(struct work_struct * work)116 static void ptn5150_irq_work(struct work_struct *work)
117 {
118 	struct ptn5150_info *info = container_of(work,
119 			struct ptn5150_info, irq_work);
120 	int ret = 0;
121 	unsigned int int_status;
122 
123 	if (!info->edev)
124 		return;
125 
126 	mutex_lock(&info->mutex);
127 
128 	/* Clear interrupt. Read would clear the register */
129 	ret = regmap_read(info->regmap, PTN5150_REG_INT_STATUS, &int_status);
130 	if (ret) {
131 		dev_err(info->dev, "failed to read INT STATUS %d\n", ret);
132 		mutex_unlock(&info->mutex);
133 		return;
134 	}
135 
136 	if (int_status) {
137 		unsigned int cable_attach;
138 
139 		cable_attach = int_status & PTN5150_REG_INT_CABLE_ATTACH_MASK;
140 		if (cable_attach) {
141 			ptn5150_check_state(info);
142 		} else {
143 			extcon_set_state_sync(info->edev,
144 					EXTCON_USB_HOST, false);
145 			extcon_set_state_sync(info->edev,
146 					EXTCON_USB, false);
147 			gpiod_set_value_cansleep(info->vbus_gpiod, 0);
148 
149 			ret = usb_role_switch_set_role(info->role_sw,
150 						       USB_ROLE_NONE);
151 			if (ret)
152 				dev_err(info->dev,
153 					"failed to set none role: %d\n",
154 					ret);
155 		}
156 	}
157 
158 	/* Clear interrupt. Read would clear the register */
159 	ret = regmap_read(info->regmap, PTN5150_REG_INT_REG_STATUS,
160 			&int_status);
161 	if (ret) {
162 		dev_err(info->dev,
163 			"failed to read INT REG STATUS %d\n", ret);
164 		mutex_unlock(&info->mutex);
165 		return;
166 	}
167 
168 	mutex_unlock(&info->mutex);
169 }
170 
171 
ptn5150_irq_handler(int irq,void * data)172 static irqreturn_t ptn5150_irq_handler(int irq, void *data)
173 {
174 	struct ptn5150_info *info = data;
175 
176 	schedule_work(&info->irq_work);
177 
178 	return IRQ_HANDLED;
179 }
180 
ptn5150_init_dev_type(struct ptn5150_info * info)181 static int ptn5150_init_dev_type(struct ptn5150_info *info)
182 {
183 	unsigned int reg_data, vendor_id, version_id;
184 	int ret;
185 
186 	ret = regmap_read(info->regmap, PTN5150_REG_DEVICE_ID, &reg_data);
187 	if (ret) {
188 		dev_err(info->dev, "failed to read DEVICE_ID %d\n", ret);
189 		return -EINVAL;
190 	}
191 
192 	vendor_id = FIELD_GET(PTN5150_REG_DEVICE_ID_VENDOR, reg_data);
193 	version_id = FIELD_GET(PTN5150_REG_DEVICE_ID_VERSION, reg_data);
194 	dev_dbg(info->dev, "Device type: version: 0x%x, vendor: 0x%x\n",
195 		version_id, vendor_id);
196 
197 	/* Clear any existing interrupts */
198 	ret = regmap_read(info->regmap, PTN5150_REG_INT_STATUS, &reg_data);
199 	if (ret) {
200 		dev_err(info->dev,
201 			"failed to read PTN5150_REG_INT_STATUS %d\n",
202 			ret);
203 		return -EINVAL;
204 	}
205 
206 	ret = regmap_read(info->regmap, PTN5150_REG_INT_REG_STATUS, &reg_data);
207 	if (ret) {
208 		dev_err(info->dev,
209 			"failed to read PTN5150_REG_INT_REG_STATUS %d\n", ret);
210 		return -EINVAL;
211 	}
212 
213 	return 0;
214 }
215 
ptn5150_work_sync_and_put(void * data)216 static void ptn5150_work_sync_and_put(void *data)
217 {
218 	struct ptn5150_info *info = data;
219 
220 	cancel_work_sync(&info->irq_work);
221 	usb_role_switch_put(info->role_sw);
222 }
223 
ptn5150_i2c_probe(struct i2c_client * i2c)224 static int ptn5150_i2c_probe(struct i2c_client *i2c)
225 {
226 	struct device *dev = &i2c->dev;
227 	struct device_node *np = i2c->dev.of_node;
228 	struct ptn5150_info *info;
229 	int ret;
230 
231 	if (!np)
232 		return -EINVAL;
233 
234 	info = devm_kzalloc(&i2c->dev, sizeof(*info), GFP_KERNEL);
235 	if (!info)
236 		return -ENOMEM;
237 	i2c_set_clientdata(i2c, info);
238 
239 	info->dev = &i2c->dev;
240 	info->i2c = i2c;
241 	info->vbus_gpiod = devm_gpiod_get(&i2c->dev, "vbus", GPIOD_OUT_LOW);
242 	if (IS_ERR(info->vbus_gpiod)) {
243 		ret = PTR_ERR(info->vbus_gpiod);
244 		if (ret == -ENOENT) {
245 			dev_info(dev, "No VBUS GPIO, ignoring VBUS control\n");
246 			info->vbus_gpiod = NULL;
247 		} else {
248 			return dev_err_probe(dev, ret, "failed to get VBUS GPIO\n");
249 		}
250 	}
251 
252 	mutex_init(&info->mutex);
253 
254 	INIT_WORK(&info->irq_work, ptn5150_irq_work);
255 
256 	info->regmap = devm_regmap_init_i2c(i2c, &ptn5150_regmap_config);
257 	if (IS_ERR(info->regmap)) {
258 		return dev_err_probe(info->dev, PTR_ERR(info->regmap),
259 				     "failed to allocate register map\n");
260 	}
261 
262 	if (i2c->irq > 0) {
263 		info->irq = i2c->irq;
264 	} else {
265 		info->int_gpiod = devm_gpiod_get(&i2c->dev, "int", GPIOD_IN);
266 		if (IS_ERR(info->int_gpiod)) {
267 			return dev_err_probe(dev, PTR_ERR(info->int_gpiod),
268 					     "failed to get INT GPIO\n");
269 		}
270 
271 		info->irq = gpiod_to_irq(info->int_gpiod);
272 		if (info->irq < 0) {
273 			dev_err(dev, "failed to get INTB IRQ\n");
274 			return info->irq;
275 		}
276 	}
277 
278 	ret = devm_request_threaded_irq(dev, info->irq, NULL,
279 					ptn5150_irq_handler,
280 					IRQF_TRIGGER_FALLING |
281 					IRQF_ONESHOT,
282 					i2c->name, info);
283 	if (ret < 0) {
284 		dev_err(dev, "failed to request handler for INTB IRQ\n");
285 		return ret;
286 	}
287 
288 	/* Allocate extcon device */
289 	info->edev = devm_extcon_dev_allocate(info->dev, ptn5150_extcon_cable);
290 	if (IS_ERR(info->edev)) {
291 		dev_err(info->dev, "failed to allocate memory for extcon\n");
292 		return -ENOMEM;
293 	}
294 
295 	/* Register extcon device */
296 	ret = devm_extcon_dev_register(info->dev, info->edev);
297 	if (ret) {
298 		dev_err(info->dev, "failed to register extcon device\n");
299 		return ret;
300 	}
301 
302 	extcon_set_property_capability(info->edev, EXTCON_USB,
303 					EXTCON_PROP_USB_VBUS);
304 	extcon_set_property_capability(info->edev, EXTCON_USB_HOST,
305 					EXTCON_PROP_USB_VBUS);
306 	extcon_set_property_capability(info->edev, EXTCON_USB_HOST,
307 					EXTCON_PROP_USB_TYPEC_POLARITY);
308 
309 	/* Initialize PTN5150 device and print vendor id and version id */
310 	ret = ptn5150_init_dev_type(info);
311 	if (ret)
312 		return -EINVAL;
313 
314 	info->role_sw = usb_role_switch_get(info->dev);
315 	if (IS_ERR(info->role_sw))
316 		return dev_err_probe(info->dev, PTR_ERR(info->role_sw),
317 				     "failed to get role switch\n");
318 
319 	ret = devm_add_action_or_reset(dev, ptn5150_work_sync_and_put, info);
320 	if (ret)
321 		return ret;
322 
323 	/*
324 	 * Update current extcon state if for example OTG connection was there
325 	 * before the probe
326 	 */
327 	mutex_lock(&info->mutex);
328 	ptn5150_check_state(info);
329 	mutex_unlock(&info->mutex);
330 
331 	return 0;
332 }
333 
334 static const struct of_device_id ptn5150_dt_match[] = {
335 	{ .compatible = "nxp,ptn5150" },
336 	{ },
337 };
338 MODULE_DEVICE_TABLE(of, ptn5150_dt_match);
339 
340 static const struct i2c_device_id ptn5150_i2c_id[] = {
341 	{ "ptn5150", 0 },
342 	{ }
343 };
344 MODULE_DEVICE_TABLE(i2c, ptn5150_i2c_id);
345 
346 static struct i2c_driver ptn5150_i2c_driver = {
347 	.driver		= {
348 		.name	= "ptn5150",
349 		.of_match_table = ptn5150_dt_match,
350 	},
351 	.probe_new	= ptn5150_i2c_probe,
352 	.id_table = ptn5150_i2c_id,
353 };
354 module_i2c_driver(ptn5150_i2c_driver);
355 
356 MODULE_DESCRIPTION("NXP PTN5150 CC logic Extcon driver");
357 MODULE_AUTHOR("Vijai Kumar K <vijaikumar.kanagarajan@gmail.com>");
358 MODULE_AUTHOR("Krzysztof Kozlowski <krzk@kernel.org>");
359 MODULE_LICENSE("GPL v2");
360