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 (PTR_ERR(palmas_usb->id_gpiod) == -EPROBE_DEFER) {
209 		return -EPROBE_DEFER;
210 	} else if (IS_ERR(palmas_usb->id_gpiod)) {
211 		dev_err(&pdev->dev, "failed to get id gpio\n");
212 		return PTR_ERR(palmas_usb->id_gpiod);
213 	}
214 
215 	palmas_usb->vbus_gpiod = devm_gpiod_get_optional(&pdev->dev, "vbus",
216 							GPIOD_IN);
217 	if (PTR_ERR(palmas_usb->vbus_gpiod) == -EPROBE_DEFER) {
218 		return -EPROBE_DEFER;
219 	} else if (IS_ERR(palmas_usb->vbus_gpiod)) {
220 		dev_err(&pdev->dev, "failed to get vbus gpio\n");
221 		return PTR_ERR(palmas_usb->vbus_gpiod);
222 	}
223 
224 	if (palmas_usb->enable_id_detection && palmas_usb->id_gpiod) {
225 		palmas_usb->enable_id_detection = false;
226 		palmas_usb->enable_gpio_id_detection = true;
227 	}
228 
229 	if (palmas_usb->enable_vbus_detection && palmas_usb->vbus_gpiod) {
230 		palmas_usb->enable_vbus_detection = false;
231 		palmas_usb->enable_gpio_vbus_detection = true;
232 	}
233 
234 	if (palmas_usb->enable_gpio_id_detection) {
235 		u32 debounce;
236 
237 		if (of_property_read_u32(node, "debounce-delay-ms", &debounce))
238 			debounce = USB_GPIO_DEBOUNCE_MS;
239 
240 		status = gpiod_set_debounce(palmas_usb->id_gpiod,
241 					    debounce * 1000);
242 		if (status < 0)
243 			palmas_usb->sw_debounce_jiffies = msecs_to_jiffies(debounce);
244 	}
245 
246 	INIT_DELAYED_WORK(&palmas_usb->wq_detectid, palmas_gpio_id_detect);
247 
248 	palmas->usb = palmas_usb;
249 	palmas_usb->palmas = palmas;
250 
251 	palmas_usb->dev	 = &pdev->dev;
252 
253 	palmas_usb_wakeup(palmas, palmas_usb->wakeup);
254 
255 	platform_set_drvdata(pdev, palmas_usb);
256 
257 	palmas_usb->edev = devm_extcon_dev_allocate(&pdev->dev,
258 						    palmas_extcon_cable);
259 	if (IS_ERR(palmas_usb->edev)) {
260 		dev_err(&pdev->dev, "failed to allocate extcon device\n");
261 		return -ENOMEM;
262 	}
263 
264 	status = devm_extcon_dev_register(&pdev->dev, palmas_usb->edev);
265 	if (status) {
266 		dev_err(&pdev->dev, "failed to register extcon device\n");
267 		return status;
268 	}
269 
270 	if (palmas_usb->enable_id_detection) {
271 		palmas_usb->id_otg_irq = regmap_irq_get_virq(palmas->irq_data,
272 							     PALMAS_ID_OTG_IRQ);
273 		palmas_usb->id_irq = regmap_irq_get_virq(palmas->irq_data,
274 							 PALMAS_ID_IRQ);
275 		status = devm_request_threaded_irq(palmas_usb->dev,
276 				palmas_usb->id_irq,
277 				NULL, palmas_id_irq_handler,
278 				IRQF_TRIGGER_FALLING | IRQF_TRIGGER_RISING |
279 				IRQF_ONESHOT,
280 				"palmas_usb_id", palmas_usb);
281 		if (status < 0) {
282 			dev_err(&pdev->dev, "can't get IRQ %d, err %d\n",
283 					palmas_usb->id_irq, status);
284 			return status;
285 		}
286 	} else if (palmas_usb->enable_gpio_id_detection) {
287 		palmas_usb->gpio_id_irq = gpiod_to_irq(palmas_usb->id_gpiod);
288 		if (palmas_usb->gpio_id_irq < 0) {
289 			dev_err(&pdev->dev, "failed to get id irq\n");
290 			return palmas_usb->gpio_id_irq;
291 		}
292 		status = devm_request_threaded_irq(&pdev->dev,
293 						   palmas_usb->gpio_id_irq,
294 						   NULL,
295 						   palmas_gpio_id_irq_handler,
296 						   IRQF_TRIGGER_RISING |
297 						   IRQF_TRIGGER_FALLING |
298 						   IRQF_ONESHOT,
299 						   "palmas_usb_id",
300 						   palmas_usb);
301 		if (status < 0) {
302 			dev_err(&pdev->dev,
303 				"failed to request handler for id irq\n");
304 			return status;
305 		}
306 	}
307 
308 	if (palmas_usb->enable_vbus_detection) {
309 		palmas_usb->vbus_otg_irq = regmap_irq_get_virq(palmas->irq_data,
310 						       PALMAS_VBUS_OTG_IRQ);
311 		palmas_usb->vbus_irq = regmap_irq_get_virq(palmas->irq_data,
312 							   PALMAS_VBUS_IRQ);
313 		status = devm_request_threaded_irq(palmas_usb->dev,
314 				palmas_usb->vbus_irq, NULL,
315 				palmas_vbus_irq_handler,
316 				IRQF_TRIGGER_FALLING | IRQF_TRIGGER_RISING |
317 				IRQF_ONESHOT,
318 				"palmas_usb_vbus", palmas_usb);
319 		if (status < 0) {
320 			dev_err(&pdev->dev, "can't get IRQ %d, err %d\n",
321 					palmas_usb->vbus_irq, status);
322 			return status;
323 		}
324 	} else if (palmas_usb->enable_gpio_vbus_detection) {
325 		/* remux GPIO_1 as VBUSDET */
326 		status = palmas_update_bits(palmas,
327 			PALMAS_PU_PD_OD_BASE,
328 			PALMAS_PRIMARY_SECONDARY_PAD1,
329 			PALMAS_PRIMARY_SECONDARY_PAD1_GPIO_1_MASK,
330 			(1 << PALMAS_PRIMARY_SECONDARY_PAD1_GPIO_1_SHIFT));
331 		if (status < 0) {
332 			dev_err(&pdev->dev, "can't remux GPIO1\n");
333 			return status;
334 		}
335 
336 		palmas_usb->vbus_otg_irq = regmap_irq_get_virq(palmas->irq_data,
337 						       PALMAS_VBUS_OTG_IRQ);
338 		palmas_usb->gpio_vbus_irq = gpiod_to_irq(palmas_usb->vbus_gpiod);
339 		if (palmas_usb->gpio_vbus_irq < 0) {
340 			dev_err(&pdev->dev, "failed to get vbus irq\n");
341 			return palmas_usb->gpio_vbus_irq;
342 		}
343 		status = devm_request_threaded_irq(&pdev->dev,
344 						palmas_usb->gpio_vbus_irq,
345 						NULL,
346 						palmas_vbus_irq_handler,
347 						IRQF_TRIGGER_FALLING |
348 						IRQF_TRIGGER_RISING |
349 						IRQF_ONESHOT,
350 						"palmas_usb_vbus",
351 						palmas_usb);
352 		if (status < 0) {
353 			dev_err(&pdev->dev,
354 				"failed to request handler for vbus irq\n");
355 			return status;
356 		}
357 	}
358 
359 	palmas_enable_irq(palmas_usb);
360 	/* perform initial detection */
361 	if (palmas_usb->enable_gpio_vbus_detection)
362 		palmas_vbus_irq_handler(palmas_usb->gpio_vbus_irq, palmas_usb);
363 	palmas_gpio_id_detect(&palmas_usb->wq_detectid.work);
364 	device_set_wakeup_capable(&pdev->dev, true);
365 	return 0;
366 }
367 
368 static int palmas_usb_remove(struct platform_device *pdev)
369 {
370 	struct palmas_usb *palmas_usb = platform_get_drvdata(pdev);
371 
372 	cancel_delayed_work_sync(&palmas_usb->wq_detectid);
373 
374 	return 0;
375 }
376 
377 #ifdef CONFIG_PM_SLEEP
378 static int palmas_usb_suspend(struct device *dev)
379 {
380 	struct palmas_usb *palmas_usb = dev_get_drvdata(dev);
381 
382 	if (device_may_wakeup(dev)) {
383 		if (palmas_usb->enable_vbus_detection)
384 			enable_irq_wake(palmas_usb->vbus_irq);
385 		if (palmas_usb->enable_gpio_vbus_detection)
386 			enable_irq_wake(palmas_usb->gpio_vbus_irq);
387 		if (palmas_usb->enable_id_detection)
388 			enable_irq_wake(palmas_usb->id_irq);
389 		if (palmas_usb->enable_gpio_id_detection)
390 			enable_irq_wake(palmas_usb->gpio_id_irq);
391 	}
392 	return 0;
393 }
394 
395 static int palmas_usb_resume(struct device *dev)
396 {
397 	struct palmas_usb *palmas_usb = dev_get_drvdata(dev);
398 
399 	if (device_may_wakeup(dev)) {
400 		if (palmas_usb->enable_vbus_detection)
401 			disable_irq_wake(palmas_usb->vbus_irq);
402 		if (palmas_usb->enable_gpio_vbus_detection)
403 			disable_irq_wake(palmas_usb->gpio_vbus_irq);
404 		if (palmas_usb->enable_id_detection)
405 			disable_irq_wake(palmas_usb->id_irq);
406 		if (palmas_usb->enable_gpio_id_detection)
407 			disable_irq_wake(palmas_usb->gpio_id_irq);
408 	}
409 
410 	/* check if GPIO states changed while suspend/resume */
411 	if (palmas_usb->enable_gpio_vbus_detection)
412 		palmas_vbus_irq_handler(palmas_usb->gpio_vbus_irq, palmas_usb);
413 	palmas_gpio_id_detect(&palmas_usb->wq_detectid.work);
414 
415 	return 0;
416 };
417 #endif
418 
419 static SIMPLE_DEV_PM_OPS(palmas_pm_ops, palmas_usb_suspend, palmas_usb_resume);
420 
421 static const struct of_device_id of_palmas_match_tbl[] = {
422 	{ .compatible = "ti,palmas-usb", },
423 	{ .compatible = "ti,palmas-usb-vid", },
424 	{ .compatible = "ti,twl6035-usb", },
425 	{ .compatible = "ti,twl6035-usb-vid", },
426 	{ /* end */ }
427 };
428 
429 static struct platform_driver palmas_usb_driver = {
430 	.probe = palmas_usb_probe,
431 	.remove = palmas_usb_remove,
432 	.driver = {
433 		.name = "palmas-usb",
434 		.of_match_table = of_palmas_match_tbl,
435 		.pm = &palmas_pm_ops,
436 	},
437 };
438 
439 module_platform_driver(palmas_usb_driver);
440 
441 MODULE_ALIAS("platform:palmas-usb");
442 MODULE_AUTHOR("Graeme Gregory <gg@slimlogic.co.uk>");
443 MODULE_DESCRIPTION("Palmas USB transceiver driver");
444 MODULE_LICENSE("GPL");
445 MODULE_DEVICE_TABLE(of, of_palmas_match_tbl);
446