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 
21 /* PTN5150 registers */
22 #define PTN5150_REG_DEVICE_ID			0x01
23 #define PTN5150_REG_CONTROL			0x02
24 #define PTN5150_REG_INT_STATUS			0x03
25 #define PTN5150_REG_CC_STATUS			0x04
26 #define PTN5150_REG_CON_DET			0x09
27 #define PTN5150_REG_VCONN_STATUS		0x0a
28 #define PTN5150_REG_RESET			0x0b
29 #define PTN5150_REG_INT_MASK			0x18
30 #define PTN5150_REG_INT_REG_STATUS		0x19
31 #define PTN5150_REG_END				PTN5150_REG_INT_REG_STATUS
32 
33 #define PTN5150_DFP_ATTACHED			0x1
34 #define PTN5150_UFP_ATTACHED			0x2
35 
36 /* Define PTN5150 MASK/SHIFT constant */
37 #define PTN5150_REG_DEVICE_ID_VERSION		GENMASK(7, 3)
38 #define PTN5150_REG_DEVICE_ID_VENDOR		GENMASK(2, 0)
39 
40 #define PTN5150_REG_CC_PORT_ATTACHMENT		GENMASK(4, 2)
41 #define PTN5150_REG_CC_VBUS_DETECTION		BIT(7)
42 #define PTN5150_REG_INT_CABLE_ATTACH_MASK	BIT(0)
43 #define PTN5150_REG_INT_CABLE_DETACH_MASK	BIT(1)
44 
45 struct ptn5150_info {
46 	struct device *dev;
47 	struct extcon_dev *edev;
48 	struct i2c_client *i2c;
49 	struct regmap *regmap;
50 	struct gpio_desc *int_gpiod;
51 	struct gpio_desc *vbus_gpiod;
52 	int irq;
53 	struct work_struct irq_work;
54 	struct mutex mutex;
55 };
56 
57 /* List of detectable cables */
58 static const unsigned int ptn5150_extcon_cable[] = {
59 	EXTCON_USB,
60 	EXTCON_USB_HOST,
61 	EXTCON_NONE,
62 };
63 
64 static const struct regmap_config ptn5150_regmap_config = {
65 	.reg_bits	= 8,
66 	.val_bits	= 8,
67 	.max_register	= PTN5150_REG_END,
68 };
69 
70 static void ptn5150_check_state(struct ptn5150_info *info)
71 {
72 	unsigned int port_status, reg_data, vbus;
73 	int ret;
74 
75 	ret = regmap_read(info->regmap, PTN5150_REG_CC_STATUS, &reg_data);
76 	if (ret) {
77 		dev_err(info->dev, "failed to read CC STATUS %d\n", ret);
78 		return;
79 	}
80 
81 	port_status = FIELD_GET(PTN5150_REG_CC_PORT_ATTACHMENT, reg_data);
82 
83 	switch (port_status) {
84 	case PTN5150_DFP_ATTACHED:
85 		extcon_set_state_sync(info->edev, EXTCON_USB_HOST, false);
86 		gpiod_set_value_cansleep(info->vbus_gpiod, 0);
87 		extcon_set_state_sync(info->edev, EXTCON_USB, true);
88 		break;
89 	case PTN5150_UFP_ATTACHED:
90 		extcon_set_state_sync(info->edev, EXTCON_USB, false);
91 		vbus = FIELD_GET(PTN5150_REG_CC_VBUS_DETECTION, reg_data);
92 		if (vbus)
93 			gpiod_set_value_cansleep(info->vbus_gpiod, 0);
94 		else
95 			gpiod_set_value_cansleep(info->vbus_gpiod, 1);
96 
97 		extcon_set_state_sync(info->edev, EXTCON_USB_HOST, true);
98 		break;
99 	default:
100 		break;
101 	}
102 }
103 
104 static void ptn5150_irq_work(struct work_struct *work)
105 {
106 	struct ptn5150_info *info = container_of(work,
107 			struct ptn5150_info, irq_work);
108 	int ret = 0;
109 	unsigned int int_status;
110 
111 	if (!info->edev)
112 		return;
113 
114 	mutex_lock(&info->mutex);
115 
116 	/* Clear interrupt. Read would clear the register */
117 	ret = regmap_read(info->regmap, PTN5150_REG_INT_STATUS, &int_status);
118 	if (ret) {
119 		dev_err(info->dev, "failed to read INT STATUS %d\n", ret);
120 		mutex_unlock(&info->mutex);
121 		return;
122 	}
123 
124 	if (int_status) {
125 		unsigned int cable_attach;
126 
127 		cable_attach = int_status & PTN5150_REG_INT_CABLE_ATTACH_MASK;
128 		if (cable_attach) {
129 			ptn5150_check_state(info);
130 		} else {
131 			extcon_set_state_sync(info->edev,
132 					EXTCON_USB_HOST, false);
133 			extcon_set_state_sync(info->edev,
134 					EXTCON_USB, false);
135 			gpiod_set_value_cansleep(info->vbus_gpiod, 0);
136 		}
137 	}
138 
139 	/* Clear interrupt. Read would clear the register */
140 	ret = regmap_read(info->regmap, PTN5150_REG_INT_REG_STATUS,
141 			&int_status);
142 	if (ret) {
143 		dev_err(info->dev,
144 			"failed to read INT REG STATUS %d\n", ret);
145 		mutex_unlock(&info->mutex);
146 		return;
147 	}
148 
149 	mutex_unlock(&info->mutex);
150 }
151 
152 
153 static irqreturn_t ptn5150_irq_handler(int irq, void *data)
154 {
155 	struct ptn5150_info *info = data;
156 
157 	schedule_work(&info->irq_work);
158 
159 	return IRQ_HANDLED;
160 }
161 
162 static int ptn5150_init_dev_type(struct ptn5150_info *info)
163 {
164 	unsigned int reg_data, vendor_id, version_id;
165 	int ret;
166 
167 	ret = regmap_read(info->regmap, PTN5150_REG_DEVICE_ID, &reg_data);
168 	if (ret) {
169 		dev_err(info->dev, "failed to read DEVICE_ID %d\n", ret);
170 		return -EINVAL;
171 	}
172 
173 	vendor_id = FIELD_GET(PTN5150_REG_DEVICE_ID_VENDOR, reg_data);
174 	version_id = FIELD_GET(PTN5150_REG_DEVICE_ID_VERSION, reg_data);
175 	dev_dbg(info->dev, "Device type: version: 0x%x, vendor: 0x%x\n",
176 		version_id, vendor_id);
177 
178 	/* Clear any existing interrupts */
179 	ret = regmap_read(info->regmap, PTN5150_REG_INT_STATUS, &reg_data);
180 	if (ret) {
181 		dev_err(info->dev,
182 			"failed to read PTN5150_REG_INT_STATUS %d\n",
183 			ret);
184 		return -EINVAL;
185 	}
186 
187 	ret = regmap_read(info->regmap, PTN5150_REG_INT_REG_STATUS, &reg_data);
188 	if (ret) {
189 		dev_err(info->dev,
190 			"failed to read PTN5150_REG_INT_REG_STATUS %d\n", ret);
191 		return -EINVAL;
192 	}
193 
194 	return 0;
195 }
196 
197 static int ptn5150_i2c_probe(struct i2c_client *i2c)
198 {
199 	struct device *dev = &i2c->dev;
200 	struct device_node *np = i2c->dev.of_node;
201 	struct ptn5150_info *info;
202 	int ret;
203 
204 	if (!np)
205 		return -EINVAL;
206 
207 	info = devm_kzalloc(&i2c->dev, sizeof(*info), GFP_KERNEL);
208 	if (!info)
209 		return -ENOMEM;
210 	i2c_set_clientdata(i2c, info);
211 
212 	info->dev = &i2c->dev;
213 	info->i2c = i2c;
214 	info->vbus_gpiod = devm_gpiod_get(&i2c->dev, "vbus", GPIOD_OUT_LOW);
215 	if (IS_ERR(info->vbus_gpiod)) {
216 		ret = PTR_ERR(info->vbus_gpiod);
217 		if (ret == -ENOENT) {
218 			dev_info(dev, "No VBUS GPIO, ignoring VBUS control\n");
219 			info->vbus_gpiod = NULL;
220 		} else {
221 			return dev_err_probe(dev, ret, "failed to get VBUS GPIO\n");
222 		}
223 	}
224 
225 	mutex_init(&info->mutex);
226 
227 	INIT_WORK(&info->irq_work, ptn5150_irq_work);
228 
229 	info->regmap = devm_regmap_init_i2c(i2c, &ptn5150_regmap_config);
230 	if (IS_ERR(info->regmap)) {
231 		return dev_err_probe(info->dev, PTR_ERR(info->regmap),
232 				     "failed to allocate register map\n");
233 	}
234 
235 	if (i2c->irq > 0) {
236 		info->irq = i2c->irq;
237 	} else {
238 		info->int_gpiod = devm_gpiod_get(&i2c->dev, "int", GPIOD_IN);
239 		if (IS_ERR(info->int_gpiod)) {
240 			return dev_err_probe(dev, PTR_ERR(info->int_gpiod),
241 					     "failed to get INT GPIO\n");
242 		}
243 
244 		info->irq = gpiod_to_irq(info->int_gpiod);
245 		if (info->irq < 0) {
246 			dev_err(dev, "failed to get INTB IRQ\n");
247 			return info->irq;
248 		}
249 	}
250 
251 	ret = devm_request_threaded_irq(dev, info->irq, NULL,
252 					ptn5150_irq_handler,
253 					IRQF_TRIGGER_FALLING |
254 					IRQF_ONESHOT,
255 					i2c->name, info);
256 	if (ret < 0) {
257 		dev_err(dev, "failed to request handler for INTB IRQ\n");
258 		return ret;
259 	}
260 
261 	/* Allocate extcon device */
262 	info->edev = devm_extcon_dev_allocate(info->dev, ptn5150_extcon_cable);
263 	if (IS_ERR(info->edev)) {
264 		dev_err(info->dev, "failed to allocate memory for extcon\n");
265 		return -ENOMEM;
266 	}
267 
268 	/* Register extcon device */
269 	ret = devm_extcon_dev_register(info->dev, info->edev);
270 	if (ret) {
271 		dev_err(info->dev, "failed to register extcon device\n");
272 		return ret;
273 	}
274 
275 	extcon_set_property_capability(info->edev, EXTCON_USB,
276 					EXTCON_PROP_USB_VBUS);
277 	extcon_set_property_capability(info->edev, EXTCON_USB_HOST,
278 					EXTCON_PROP_USB_VBUS);
279 	extcon_set_property_capability(info->edev, EXTCON_USB_HOST,
280 					EXTCON_PROP_USB_TYPEC_POLARITY);
281 
282 	/* Initialize PTN5150 device and print vendor id and version id */
283 	ret = ptn5150_init_dev_type(info);
284 	if (ret)
285 		return -EINVAL;
286 
287 	/*
288 	 * Update current extcon state if for example OTG connection was there
289 	 * before the probe
290 	 */
291 	mutex_lock(&info->mutex);
292 	ptn5150_check_state(info);
293 	mutex_unlock(&info->mutex);
294 
295 	return 0;
296 }
297 
298 static const struct of_device_id ptn5150_dt_match[] = {
299 	{ .compatible = "nxp,ptn5150" },
300 	{ },
301 };
302 MODULE_DEVICE_TABLE(of, ptn5150_dt_match);
303 
304 static const struct i2c_device_id ptn5150_i2c_id[] = {
305 	{ "ptn5150", 0 },
306 	{ }
307 };
308 MODULE_DEVICE_TABLE(i2c, ptn5150_i2c_id);
309 
310 static struct i2c_driver ptn5150_i2c_driver = {
311 	.driver		= {
312 		.name	= "ptn5150",
313 		.of_match_table = ptn5150_dt_match,
314 	},
315 	.probe_new	= ptn5150_i2c_probe,
316 	.id_table = ptn5150_i2c_id,
317 };
318 module_i2c_driver(ptn5150_i2c_driver);
319 
320 MODULE_DESCRIPTION("NXP PTN5150 CC logic Extcon driver");
321 MODULE_AUTHOR("Vijai Kumar K <vijaikumar.kanagarajan@gmail.com>");
322 MODULE_AUTHOR("Krzysztof Kozlowski <krzk@kernel.org>");
323 MODULE_LICENSE("GPL v2");
324