1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Palmas USB transceiver driver
4  *
5  * Copyright (C) 2013 Texas Instruments Incorporated - http://www.ti.com
6  * Author: Graeme Gregory <gg@slimlogic.co.uk>
7  * Author: Kishon Vijay Abraham I <kishon@ti.com>
8  * Based on twl6030_usb.c
9  * Author: Hema HK <hemahk@ti.com>
10  */
11 
12 #include <linux/module.h>
13 #include <linux/interrupt.h>
14 #include <linux/platform_device.h>
15 #include <linux/slab.h>
16 #include <linux/err.h>
17 #include <linux/mfd/palmas.h>
18 #include <linux/of.h>
19 #include <linux/of_platform.h>
20 #include <linux/of_gpio.h>
21 #include <linux/gpio/consumer.h>
22 #include <linux/workqueue.h>
23 
24 #define USB_GPIO_DEBOUNCE_MS	20	/* ms */
25 
26 static const unsigned int palmas_extcon_cable[] = {
27 	EXTCON_USB,
28 	EXTCON_USB_HOST,
29 	EXTCON_NONE,
30 };
31 
32 static void palmas_usb_wakeup(struct palmas *palmas, int enable)
33 {
34 	if (enable)
35 		palmas_write(palmas, PALMAS_USB_OTG_BASE, PALMAS_USB_WAKEUP,
36 			PALMAS_USB_WAKEUP_ID_WK_UP_COMP);
37 	else
38 		palmas_write(palmas, PALMAS_USB_OTG_BASE, PALMAS_USB_WAKEUP, 0);
39 }
40 
41 static irqreturn_t palmas_vbus_irq_handler(int irq, void *_palmas_usb)
42 {
43 	struct palmas_usb *palmas_usb = _palmas_usb;
44 	struct extcon_dev *edev = palmas_usb->edev;
45 	unsigned int vbus_line_state;
46 
47 	palmas_read(palmas_usb->palmas, PALMAS_INTERRUPT_BASE,
48 		PALMAS_INT3_LINE_STATE, &vbus_line_state);
49 
50 	if (vbus_line_state & PALMAS_INT3_LINE_STATE_VBUS) {
51 		if (palmas_usb->linkstat != PALMAS_USB_STATE_VBUS) {
52 			palmas_usb->linkstat = PALMAS_USB_STATE_VBUS;
53 			extcon_set_state_sync(edev, EXTCON_USB, true);
54 			dev_dbg(palmas_usb->dev, "USB cable is attached\n");
55 		} else {
56 			dev_dbg(palmas_usb->dev,
57 				"Spurious connect event detected\n");
58 		}
59 	} else if (!(vbus_line_state & PALMAS_INT3_LINE_STATE_VBUS)) {
60 		if (palmas_usb->linkstat == PALMAS_USB_STATE_VBUS) {
61 			palmas_usb->linkstat = PALMAS_USB_STATE_DISCONNECT;
62 			extcon_set_state_sync(edev, EXTCON_USB, false);
63 			dev_dbg(palmas_usb->dev, "USB cable is detached\n");
64 		} else {
65 			dev_dbg(palmas_usb->dev,
66 				"Spurious disconnect event detected\n");
67 		}
68 	}
69 
70 	return IRQ_HANDLED;
71 }
72 
73 static irqreturn_t palmas_id_irq_handler(int irq, void *_palmas_usb)
74 {
75 	unsigned int set, id_src;
76 	struct palmas_usb *palmas_usb = _palmas_usb;
77 	struct extcon_dev *edev = palmas_usb->edev;
78 
79 	palmas_read(palmas_usb->palmas, PALMAS_USB_OTG_BASE,
80 		PALMAS_USB_ID_INT_LATCH_SET, &set);
81 	palmas_read(palmas_usb->palmas, PALMAS_USB_OTG_BASE,
82 		PALMAS_USB_ID_INT_SRC, &id_src);
83 
84 	if ((set & PALMAS_USB_ID_INT_SRC_ID_GND) &&
85 				(id_src & PALMAS_USB_ID_INT_SRC_ID_GND)) {
86 		palmas_write(palmas_usb->palmas, PALMAS_USB_OTG_BASE,
87 			PALMAS_USB_ID_INT_LATCH_CLR,
88 			PALMAS_USB_ID_INT_EN_HI_CLR_ID_GND);
89 		palmas_usb->linkstat = PALMAS_USB_STATE_ID;
90 		extcon_set_state_sync(edev, EXTCON_USB_HOST, true);
91 		dev_dbg(palmas_usb->dev, "USB-HOST cable is attached\n");
92 	} else if ((set & PALMAS_USB_ID_INT_SRC_ID_FLOAT) &&
93 				(id_src & PALMAS_USB_ID_INT_SRC_ID_FLOAT)) {
94 		palmas_write(palmas_usb->palmas, PALMAS_USB_OTG_BASE,
95 			PALMAS_USB_ID_INT_LATCH_CLR,
96 			PALMAS_USB_ID_INT_EN_HI_CLR_ID_FLOAT);
97 		palmas_usb->linkstat = PALMAS_USB_STATE_DISCONNECT;
98 		extcon_set_state_sync(edev, EXTCON_USB_HOST, false);
99 		dev_dbg(palmas_usb->dev, "USB-HOST cable is detached\n");
100 	} else if ((palmas_usb->linkstat == PALMAS_USB_STATE_ID) &&
101 				(!(set & PALMAS_USB_ID_INT_SRC_ID_GND))) {
102 		palmas_usb->linkstat = PALMAS_USB_STATE_DISCONNECT;
103 		extcon_set_state_sync(edev, EXTCON_USB_HOST, false);
104 		dev_dbg(palmas_usb->dev, "USB-HOST cable is detached\n");
105 	} else if ((palmas_usb->linkstat == PALMAS_USB_STATE_DISCONNECT) &&
106 				(id_src & PALMAS_USB_ID_INT_SRC_ID_GND)) {
107 		palmas_usb->linkstat = PALMAS_USB_STATE_ID;
108 		extcon_set_state_sync(edev, EXTCON_USB_HOST, true);
109 		dev_dbg(palmas_usb->dev, " USB-HOST cable is attached\n");
110 	}
111 
112 	return IRQ_HANDLED;
113 }
114 
115 static void palmas_gpio_id_detect(struct work_struct *work)
116 {
117 	int id;
118 	struct palmas_usb *palmas_usb = container_of(to_delayed_work(work),
119 						     struct palmas_usb,
120 						     wq_detectid);
121 	struct extcon_dev *edev = palmas_usb->edev;
122 
123 	if (!palmas_usb->id_gpiod)
124 		return;
125 
126 	id = gpiod_get_value_cansleep(palmas_usb->id_gpiod);
127 
128 	if (id) {
129 		extcon_set_state_sync(edev, EXTCON_USB_HOST, false);
130 		dev_dbg(palmas_usb->dev, "USB-HOST cable is detached\n");
131 	} else {
132 		extcon_set_state_sync(edev, EXTCON_USB_HOST, true);
133 		dev_dbg(palmas_usb->dev, "USB-HOST cable is attached\n");
134 	}
135 }
136 
137 static irqreturn_t palmas_gpio_id_irq_handler(int irq, void *_palmas_usb)
138 {
139 	struct palmas_usb *palmas_usb = _palmas_usb;
140 
141 	queue_delayed_work(system_power_efficient_wq, &palmas_usb->wq_detectid,
142 			   palmas_usb->sw_debounce_jiffies);
143 
144 	return IRQ_HANDLED;
145 }
146 
147 static void palmas_enable_irq(struct palmas_usb *palmas_usb)
148 {
149 	palmas_write(palmas_usb->palmas, PALMAS_USB_OTG_BASE,
150 		PALMAS_USB_VBUS_CTRL_SET,
151 		PALMAS_USB_VBUS_CTRL_SET_VBUS_ACT_COMP);
152 
153 	if (palmas_usb->enable_id_detection) {
154 		palmas_write(palmas_usb->palmas, PALMAS_USB_OTG_BASE,
155 			     PALMAS_USB_ID_CTRL_SET,
156 			     PALMAS_USB_ID_CTRL_SET_ID_ACT_COMP);
157 
158 		palmas_write(palmas_usb->palmas, PALMAS_USB_OTG_BASE,
159 			     PALMAS_USB_ID_INT_EN_HI_SET,
160 			     PALMAS_USB_ID_INT_EN_HI_SET_ID_GND |
161 			     PALMAS_USB_ID_INT_EN_HI_SET_ID_FLOAT);
162 	}
163 
164 	if (palmas_usb->enable_vbus_detection)
165 		palmas_vbus_irq_handler(palmas_usb->vbus_irq, palmas_usb);
166 
167 	/* cold plug for host mode needs this delay */
168 	if (palmas_usb->enable_id_detection) {
169 		msleep(30);
170 		palmas_id_irq_handler(palmas_usb->id_irq, palmas_usb);
171 	}
172 }
173 
174 static int palmas_usb_probe(struct platform_device *pdev)
175 {
176 	struct palmas *palmas = dev_get_drvdata(pdev->dev.parent);
177 	struct palmas_usb_platform_data	*pdata = dev_get_platdata(&pdev->dev);
178 	struct device_node *node = pdev->dev.of_node;
179 	struct palmas_usb *palmas_usb;
180 	int status;
181 
182 	if (!palmas) {
183 		dev_err(&pdev->dev, "failed to get valid parent\n");
184 		return -EINVAL;
185 	}
186 
187 	palmas_usb = devm_kzalloc(&pdev->dev, sizeof(*palmas_usb), GFP_KERNEL);
188 	if (!palmas_usb)
189 		return -ENOMEM;
190 
191 	if (node && !pdata) {
192 		palmas_usb->wakeup = of_property_read_bool(node, "ti,wakeup");
193 		palmas_usb->enable_id_detection = of_property_read_bool(node,
194 						"ti,enable-id-detection");
195 		palmas_usb->enable_vbus_detection = of_property_read_bool(node,
196 						"ti,enable-vbus-detection");
197 	} else {
198 		palmas_usb->wakeup = true;
199 		palmas_usb->enable_id_detection = true;
200 		palmas_usb->enable_vbus_detection = true;
201 
202 		if (pdata)
203 			palmas_usb->wakeup = pdata->wakeup;
204 	}
205 
206 	palmas_usb->id_gpiod = devm_gpiod_get_optional(&pdev->dev, "id",
207 							GPIOD_IN);
208 	if (IS_ERR(palmas_usb->id_gpiod)) {
209 		dev_err(&pdev->dev, "failed to get id gpio\n");
210 		return PTR_ERR(palmas_usb->id_gpiod);
211 	}
212 
213 	palmas_usb->vbus_gpiod = devm_gpiod_get_optional(&pdev->dev, "vbus",
214 							GPIOD_IN);
215 	if (IS_ERR(palmas_usb->vbus_gpiod)) {
216 		dev_err(&pdev->dev, "failed to get vbus gpio\n");
217 		return PTR_ERR(palmas_usb->vbus_gpiod);
218 	}
219 
220 	if (palmas_usb->enable_id_detection && palmas_usb->id_gpiod) {
221 		palmas_usb->enable_id_detection = false;
222 		palmas_usb->enable_gpio_id_detection = true;
223 	}
224 
225 	if (palmas_usb->enable_vbus_detection && palmas_usb->vbus_gpiod) {
226 		palmas_usb->enable_vbus_detection = false;
227 		palmas_usb->enable_gpio_vbus_detection = true;
228 	}
229 
230 	if (palmas_usb->enable_gpio_id_detection) {
231 		u32 debounce;
232 
233 		if (of_property_read_u32(node, "debounce-delay-ms", &debounce))
234 			debounce = USB_GPIO_DEBOUNCE_MS;
235 
236 		status = gpiod_set_debounce(palmas_usb->id_gpiod,
237 					    debounce * 1000);
238 		if (status < 0)
239 			palmas_usb->sw_debounce_jiffies = msecs_to_jiffies(debounce);
240 	}
241 
242 	INIT_DELAYED_WORK(&palmas_usb->wq_detectid, palmas_gpio_id_detect);
243 
244 	palmas->usb = palmas_usb;
245 	palmas_usb->palmas = palmas;
246 
247 	palmas_usb->dev	 = &pdev->dev;
248 
249 	palmas_usb_wakeup(palmas, palmas_usb->wakeup);
250 
251 	platform_set_drvdata(pdev, palmas_usb);
252 
253 	palmas_usb->edev = devm_extcon_dev_allocate(&pdev->dev,
254 						    palmas_extcon_cable);
255 	if (IS_ERR(palmas_usb->edev)) {
256 		dev_err(&pdev->dev, "failed to allocate extcon device\n");
257 		return -ENOMEM;
258 	}
259 
260 	status = devm_extcon_dev_register(&pdev->dev, palmas_usb->edev);
261 	if (status) {
262 		dev_err(&pdev->dev, "failed to register extcon device\n");
263 		return status;
264 	}
265 
266 	if (palmas_usb->enable_id_detection) {
267 		palmas_usb->id_otg_irq = regmap_irq_get_virq(palmas->irq_data,
268 							     PALMAS_ID_OTG_IRQ);
269 		palmas_usb->id_irq = regmap_irq_get_virq(palmas->irq_data,
270 							 PALMAS_ID_IRQ);
271 		status = devm_request_threaded_irq(palmas_usb->dev,
272 				palmas_usb->id_irq,
273 				NULL, palmas_id_irq_handler,
274 				IRQF_TRIGGER_FALLING | IRQF_TRIGGER_RISING |
275 				IRQF_ONESHOT,
276 				"palmas_usb_id", palmas_usb);
277 		if (status < 0) {
278 			dev_err(&pdev->dev, "can't get IRQ %d, err %d\n",
279 					palmas_usb->id_irq, status);
280 			return status;
281 		}
282 	} else if (palmas_usb->enable_gpio_id_detection) {
283 		palmas_usb->gpio_id_irq = gpiod_to_irq(palmas_usb->id_gpiod);
284 		if (palmas_usb->gpio_id_irq < 0) {
285 			dev_err(&pdev->dev, "failed to get id irq\n");
286 			return palmas_usb->gpio_id_irq;
287 		}
288 		status = devm_request_threaded_irq(&pdev->dev,
289 						   palmas_usb->gpio_id_irq,
290 						   NULL,
291 						   palmas_gpio_id_irq_handler,
292 						   IRQF_TRIGGER_RISING |
293 						   IRQF_TRIGGER_FALLING |
294 						   IRQF_ONESHOT,
295 						   "palmas_usb_id",
296 						   palmas_usb);
297 		if (status < 0) {
298 			dev_err(&pdev->dev,
299 				"failed to request handler for id irq\n");
300 			return status;
301 		}
302 	}
303 
304 	if (palmas_usb->enable_vbus_detection) {
305 		palmas_usb->vbus_otg_irq = regmap_irq_get_virq(palmas->irq_data,
306 						       PALMAS_VBUS_OTG_IRQ);
307 		palmas_usb->vbus_irq = regmap_irq_get_virq(palmas->irq_data,
308 							   PALMAS_VBUS_IRQ);
309 		status = devm_request_threaded_irq(palmas_usb->dev,
310 				palmas_usb->vbus_irq, NULL,
311 				palmas_vbus_irq_handler,
312 				IRQF_TRIGGER_FALLING | IRQF_TRIGGER_RISING |
313 				IRQF_ONESHOT,
314 				"palmas_usb_vbus", palmas_usb);
315 		if (status < 0) {
316 			dev_err(&pdev->dev, "can't get IRQ %d, err %d\n",
317 					palmas_usb->vbus_irq, status);
318 			return status;
319 		}
320 	} else if (palmas_usb->enable_gpio_vbus_detection) {
321 		/* remux GPIO_1 as VBUSDET */
322 		status = palmas_update_bits(palmas,
323 			PALMAS_PU_PD_OD_BASE,
324 			PALMAS_PRIMARY_SECONDARY_PAD1,
325 			PALMAS_PRIMARY_SECONDARY_PAD1_GPIO_1_MASK,
326 			(1 << PALMAS_PRIMARY_SECONDARY_PAD1_GPIO_1_SHIFT));
327 		if (status < 0) {
328 			dev_err(&pdev->dev, "can't remux GPIO1\n");
329 			return status;
330 		}
331 
332 		palmas_usb->vbus_otg_irq = regmap_irq_get_virq(palmas->irq_data,
333 						       PALMAS_VBUS_OTG_IRQ);
334 		palmas_usb->gpio_vbus_irq = gpiod_to_irq(palmas_usb->vbus_gpiod);
335 		if (palmas_usb->gpio_vbus_irq < 0) {
336 			dev_err(&pdev->dev, "failed to get vbus irq\n");
337 			return palmas_usb->gpio_vbus_irq;
338 		}
339 		status = devm_request_threaded_irq(&pdev->dev,
340 						palmas_usb->gpio_vbus_irq,
341 						NULL,
342 						palmas_vbus_irq_handler,
343 						IRQF_TRIGGER_FALLING |
344 						IRQF_TRIGGER_RISING |
345 						IRQF_ONESHOT,
346 						"palmas_usb_vbus",
347 						palmas_usb);
348 		if (status < 0) {
349 			dev_err(&pdev->dev,
350 				"failed to request handler for vbus irq\n");
351 			return status;
352 		}
353 	}
354 
355 	palmas_enable_irq(palmas_usb);
356 	/* perform initial detection */
357 	if (palmas_usb->enable_gpio_vbus_detection)
358 		palmas_vbus_irq_handler(palmas_usb->gpio_vbus_irq, palmas_usb);
359 	palmas_gpio_id_detect(&palmas_usb->wq_detectid.work);
360 	device_set_wakeup_capable(&pdev->dev, true);
361 	return 0;
362 }
363 
364 static int palmas_usb_remove(struct platform_device *pdev)
365 {
366 	struct palmas_usb *palmas_usb = platform_get_drvdata(pdev);
367 
368 	cancel_delayed_work_sync(&palmas_usb->wq_detectid);
369 
370 	return 0;
371 }
372 
373 #ifdef CONFIG_PM_SLEEP
374 static int palmas_usb_suspend(struct device *dev)
375 {
376 	struct palmas_usb *palmas_usb = dev_get_drvdata(dev);
377 
378 	if (device_may_wakeup(dev)) {
379 		if (palmas_usb->enable_vbus_detection)
380 			enable_irq_wake(palmas_usb->vbus_irq);
381 		if (palmas_usb->enable_gpio_vbus_detection)
382 			enable_irq_wake(palmas_usb->gpio_vbus_irq);
383 		if (palmas_usb->enable_id_detection)
384 			enable_irq_wake(palmas_usb->id_irq);
385 		if (palmas_usb->enable_gpio_id_detection)
386 			enable_irq_wake(palmas_usb->gpio_id_irq);
387 	}
388 	return 0;
389 }
390 
391 static int palmas_usb_resume(struct device *dev)
392 {
393 	struct palmas_usb *palmas_usb = dev_get_drvdata(dev);
394 
395 	if (device_may_wakeup(dev)) {
396 		if (palmas_usb->enable_vbus_detection)
397 			disable_irq_wake(palmas_usb->vbus_irq);
398 		if (palmas_usb->enable_gpio_vbus_detection)
399 			disable_irq_wake(palmas_usb->gpio_vbus_irq);
400 		if (palmas_usb->enable_id_detection)
401 			disable_irq_wake(palmas_usb->id_irq);
402 		if (palmas_usb->enable_gpio_id_detection)
403 			disable_irq_wake(palmas_usb->gpio_id_irq);
404 	}
405 
406 	/* check if GPIO states changed while suspend/resume */
407 	if (palmas_usb->enable_gpio_vbus_detection)
408 		palmas_vbus_irq_handler(palmas_usb->gpio_vbus_irq, palmas_usb);
409 	palmas_gpio_id_detect(&palmas_usb->wq_detectid.work);
410 
411 	return 0;
412 };
413 #endif
414 
415 static SIMPLE_DEV_PM_OPS(palmas_pm_ops, palmas_usb_suspend, palmas_usb_resume);
416 
417 static const struct of_device_id of_palmas_match_tbl[] = {
418 	{ .compatible = "ti,palmas-usb", },
419 	{ .compatible = "ti,palmas-usb-vid", },
420 	{ .compatible = "ti,twl6035-usb", },
421 	{ .compatible = "ti,twl6035-usb-vid", },
422 	{ /* end */ }
423 };
424 
425 static struct platform_driver palmas_usb_driver = {
426 	.probe = palmas_usb_probe,
427 	.remove = palmas_usb_remove,
428 	.driver = {
429 		.name = "palmas-usb",
430 		.of_match_table = of_palmas_match_tbl,
431 		.pm = &palmas_pm_ops,
432 	},
433 };
434 
435 module_platform_driver(palmas_usb_driver);
436 
437 MODULE_ALIAS("platform:palmas-usb");
438 MODULE_AUTHOR("Graeme Gregory <gg@slimlogic.co.uk>");
439 MODULE_DESCRIPTION("Palmas USB transceiver driver");
440 MODULE_LICENSE("GPL");
441 MODULE_DEVICE_TABLE(of, of_palmas_match_tbl);
442