1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * twl6030_usb - TWL6030 USB transceiver, talking to OMAP OTG driver.
4  *
5  * Copyright (C) 2010 Texas Instruments Incorporated - https://www.ti.com
6  *
7  * Author: Hema HK <hemahk@ti.com>
8  */
9 
10 #include <linux/module.h>
11 #include <linux/init.h>
12 #include <linux/interrupt.h>
13 #include <linux/platform_device.h>
14 #include <linux/io.h>
15 #include <linux/usb/musb.h>
16 #include <linux/usb/phy_companion.h>
17 #include <linux/phy/omap_usb.h>
18 #include <linux/mfd/twl.h>
19 #include <linux/regulator/consumer.h>
20 #include <linux/err.h>
21 #include <linux/slab.h>
22 #include <linux/delay.h>
23 #include <linux/of.h>
24 
25 /* usb register definitions */
26 #define USB_VENDOR_ID_LSB		0x00
27 #define USB_VENDOR_ID_MSB		0x01
28 #define USB_PRODUCT_ID_LSB		0x02
29 #define USB_PRODUCT_ID_MSB		0x03
30 #define USB_VBUS_CTRL_SET		0x04
31 #define USB_VBUS_CTRL_CLR		0x05
32 #define USB_ID_CTRL_SET			0x06
33 #define USB_ID_CTRL_CLR			0x07
34 #define USB_VBUS_INT_SRC		0x08
35 #define USB_VBUS_INT_LATCH_SET		0x09
36 #define USB_VBUS_INT_LATCH_CLR		0x0A
37 #define USB_VBUS_INT_EN_LO_SET		0x0B
38 #define USB_VBUS_INT_EN_LO_CLR		0x0C
39 #define USB_VBUS_INT_EN_HI_SET		0x0D
40 #define USB_VBUS_INT_EN_HI_CLR		0x0E
41 #define USB_ID_INT_SRC			0x0F
42 #define USB_ID_INT_LATCH_SET		0x10
43 #define USB_ID_INT_LATCH_CLR		0x11
44 
45 #define USB_ID_INT_EN_LO_SET		0x12
46 #define USB_ID_INT_EN_LO_CLR		0x13
47 #define USB_ID_INT_EN_HI_SET		0x14
48 #define USB_ID_INT_EN_HI_CLR		0x15
49 #define USB_OTG_ADP_CTRL		0x16
50 #define USB_OTG_ADP_HIGH		0x17
51 #define USB_OTG_ADP_LOW			0x18
52 #define USB_OTG_ADP_RISE		0x19
53 #define USB_OTG_REVISION		0x1A
54 
55 /* to be moved to LDO */
56 #define TWL6030_MISC2			0xE5
57 #define TWL6030_CFG_LDO_PD2		0xF5
58 #define TWL6030_BACKUP_REG		0xFA
59 
60 #define STS_HW_CONDITIONS		0x21
61 
62 /* In module TWL6030_MODULE_PM_MASTER */
63 #define STS_HW_CONDITIONS		0x21
64 #define STS_USB_ID			BIT(2)
65 
66 /* In module TWL6030_MODULE_PM_RECEIVER */
67 #define VUSB_CFG_TRANS			0x71
68 #define VUSB_CFG_STATE			0x72
69 #define VUSB_CFG_VOLTAGE		0x73
70 
71 /* in module TWL6030_MODULE_MAIN_CHARGE */
72 
73 #define CHARGERUSB_CTRL1		0x8
74 
75 #define CONTROLLER_STAT1		0x03
76 #define	VBUS_DET			BIT(2)
77 
78 struct twl6030_usb {
79 	struct phy_companion	comparator;
80 	struct device		*dev;
81 
82 	/* for vbus reporting with irqs disabled */
83 	spinlock_t		lock;
84 
85 	struct regulator		*usb3v3;
86 
87 	/* used to check initial cable status after probe */
88 	struct delayed_work	get_status_work;
89 
90 	/* used to set vbus, in atomic path */
91 	struct work_struct	set_vbus_work;
92 
93 	int			irq1;
94 	int			irq2;
95 	enum musb_vbus_id_status linkstat;
96 	u8			asleep;
97 	bool			vbus_enable;
98 };
99 
100 #define	comparator_to_twl(x) container_of((x), struct twl6030_usb, comparator)
101 
102 /*-------------------------------------------------------------------------*/
103 
104 static inline int twl6030_writeb(struct twl6030_usb *twl, u8 module,
105 						u8 data, u8 address)
106 {
107 	int ret = 0;
108 
109 	ret = twl_i2c_write_u8(module, data, address);
110 	if (ret < 0)
111 		dev_err(twl->dev,
112 			"Write[0x%x] Error %d\n", address, ret);
113 	return ret;
114 }
115 
116 static inline u8 twl6030_readb(struct twl6030_usb *twl, u8 module, u8 address)
117 {
118 	u8 data;
119 	int ret;
120 
121 	ret = twl_i2c_read_u8(module, &data, address);
122 	if (ret >= 0)
123 		ret = data;
124 	else
125 		dev_err(twl->dev,
126 			"readb[0x%x,0x%x] Error %d\n",
127 					module, address, ret);
128 	return ret;
129 }
130 
131 static int twl6030_start_srp(struct phy_companion *comparator)
132 {
133 	struct twl6030_usb *twl = comparator_to_twl(comparator);
134 
135 	twl6030_writeb(twl, TWL_MODULE_USB, 0x24, USB_VBUS_CTRL_SET);
136 	twl6030_writeb(twl, TWL_MODULE_USB, 0x84, USB_VBUS_CTRL_SET);
137 
138 	mdelay(100);
139 	twl6030_writeb(twl, TWL_MODULE_USB, 0xa0, USB_VBUS_CTRL_CLR);
140 
141 	return 0;
142 }
143 
144 static int twl6030_usb_ldo_init(struct twl6030_usb *twl)
145 {
146 	/* Set to OTG_REV 1.3 and turn on the ID_WAKEUP_COMP */
147 	twl6030_writeb(twl, TWL6030_MODULE_ID0, 0x1, TWL6030_BACKUP_REG);
148 
149 	/* Program CFG_LDO_PD2 register and set VUSB bit */
150 	twl6030_writeb(twl, TWL6030_MODULE_ID0, 0x1, TWL6030_CFG_LDO_PD2);
151 
152 	/* Program MISC2 register and set bit VUSB_IN_VBAT */
153 	twl6030_writeb(twl, TWL6030_MODULE_ID0, 0x10, TWL6030_MISC2);
154 
155 	twl->usb3v3 = regulator_get(twl->dev, "usb");
156 	if (IS_ERR(twl->usb3v3))
157 		return -ENODEV;
158 
159 	/* Program the USB_VBUS_CTRL_SET and set VBUS_ACT_COMP bit */
160 	twl6030_writeb(twl, TWL_MODULE_USB, 0x4, USB_VBUS_CTRL_SET);
161 
162 	/*
163 	 * Program the USB_ID_CTRL_SET register to enable GND drive
164 	 * and the ID comparators
165 	 */
166 	twl6030_writeb(twl, TWL_MODULE_USB, 0x14, USB_ID_CTRL_SET);
167 
168 	return 0;
169 }
170 
171 static ssize_t vbus_show(struct device *dev,
172 			struct device_attribute *attr, char *buf)
173 {
174 	struct twl6030_usb *twl = dev_get_drvdata(dev);
175 	unsigned long flags;
176 	int ret = -EINVAL;
177 
178 	spin_lock_irqsave(&twl->lock, flags);
179 
180 	switch (twl->linkstat) {
181 	case MUSB_VBUS_VALID:
182 	       ret = snprintf(buf, PAGE_SIZE, "vbus\n");
183 	       break;
184 	case MUSB_ID_GROUND:
185 	       ret = snprintf(buf, PAGE_SIZE, "id\n");
186 	       break;
187 	case MUSB_VBUS_OFF:
188 	       ret = snprintf(buf, PAGE_SIZE, "none\n");
189 	       break;
190 	default:
191 	       ret = snprintf(buf, PAGE_SIZE, "UNKNOWN\n");
192 	}
193 	spin_unlock_irqrestore(&twl->lock, flags);
194 
195 	return ret;
196 }
197 static DEVICE_ATTR_RO(vbus);
198 
199 static struct attribute *twl6030_attrs[] = {
200 	&dev_attr_vbus.attr,
201 	NULL,
202 };
203 ATTRIBUTE_GROUPS(twl6030);
204 
205 static irqreturn_t twl6030_usb_irq(int irq, void *_twl)
206 {
207 	struct twl6030_usb *twl = _twl;
208 	enum musb_vbus_id_status status = MUSB_UNKNOWN;
209 	u8 vbus_state, hw_state;
210 	int ret;
211 
212 	hw_state = twl6030_readb(twl, TWL6030_MODULE_ID0, STS_HW_CONDITIONS);
213 
214 	vbus_state = twl6030_readb(twl, TWL_MODULE_MAIN_CHARGE,
215 						CONTROLLER_STAT1);
216 	if (!(hw_state & STS_USB_ID)) {
217 		if (vbus_state & VBUS_DET) {
218 			ret = regulator_enable(twl->usb3v3);
219 			if (ret)
220 				dev_err(twl->dev, "Failed to enable usb3v3\n");
221 
222 			twl->asleep = 1;
223 			status = MUSB_VBUS_VALID;
224 			twl->linkstat = status;
225 			ret = musb_mailbox(status);
226 			if (ret)
227 				twl->linkstat = MUSB_UNKNOWN;
228 		} else {
229 			if (twl->linkstat != MUSB_UNKNOWN) {
230 				status = MUSB_VBUS_OFF;
231 				twl->linkstat = status;
232 				ret = musb_mailbox(status);
233 				if (ret)
234 					twl->linkstat = MUSB_UNKNOWN;
235 				if (twl->asleep) {
236 					regulator_disable(twl->usb3v3);
237 					twl->asleep = 0;
238 				}
239 			}
240 		}
241 	}
242 	sysfs_notify(&twl->dev->kobj, NULL, "vbus");
243 
244 	return IRQ_HANDLED;
245 }
246 
247 static irqreturn_t twl6030_usbotg_irq(int irq, void *_twl)
248 {
249 	struct twl6030_usb *twl = _twl;
250 	enum musb_vbus_id_status status = MUSB_UNKNOWN;
251 	u8 hw_state;
252 	int ret;
253 
254 	hw_state = twl6030_readb(twl, TWL6030_MODULE_ID0, STS_HW_CONDITIONS);
255 
256 	if (hw_state & STS_USB_ID) {
257 		ret = regulator_enable(twl->usb3v3);
258 		if (ret)
259 			dev_err(twl->dev, "Failed to enable usb3v3\n");
260 
261 		twl->asleep = 1;
262 		twl6030_writeb(twl, TWL_MODULE_USB, 0x1, USB_ID_INT_EN_HI_CLR);
263 		twl6030_writeb(twl, TWL_MODULE_USB, 0x10, USB_ID_INT_EN_HI_SET);
264 		status = MUSB_ID_GROUND;
265 		twl->linkstat = status;
266 		ret = musb_mailbox(status);
267 		if (ret)
268 			twl->linkstat = MUSB_UNKNOWN;
269 	} else  {
270 		twl6030_writeb(twl, TWL_MODULE_USB, 0x10, USB_ID_INT_EN_HI_CLR);
271 		twl6030_writeb(twl, TWL_MODULE_USB, 0x1, USB_ID_INT_EN_HI_SET);
272 	}
273 	twl6030_writeb(twl, TWL_MODULE_USB, status, USB_ID_INT_LATCH_CLR);
274 
275 	return IRQ_HANDLED;
276 }
277 
278 static void twl6030_status_work(struct work_struct *work)
279 {
280 	struct twl6030_usb *twl = container_of(work, struct twl6030_usb,
281 					       get_status_work.work);
282 
283 	twl6030_usb_irq(twl->irq2, twl);
284 	twl6030_usbotg_irq(twl->irq1, twl);
285 }
286 
287 static int twl6030_enable_irq(struct twl6030_usb *twl)
288 {
289 	twl6030_writeb(twl, TWL_MODULE_USB, 0x1, USB_ID_INT_EN_HI_SET);
290 	twl6030_interrupt_unmask(0x05, REG_INT_MSK_LINE_C);
291 	twl6030_interrupt_unmask(0x05, REG_INT_MSK_STS_C);
292 
293 	twl6030_interrupt_unmask(TWL6030_CHARGER_CTRL_INT_MASK,
294 				REG_INT_MSK_LINE_C);
295 	twl6030_interrupt_unmask(TWL6030_CHARGER_CTRL_INT_MASK,
296 				REG_INT_MSK_STS_C);
297 
298 	return 0;
299 }
300 
301 static void otg_set_vbus_work(struct work_struct *data)
302 {
303 	struct twl6030_usb *twl = container_of(data, struct twl6030_usb,
304 								set_vbus_work);
305 
306 	/*
307 	 * Start driving VBUS. Set OPA_MODE bit in CHARGERUSB_CTRL1
308 	 * register. This enables boost mode.
309 	 */
310 
311 	if (twl->vbus_enable)
312 		twl6030_writeb(twl, TWL_MODULE_MAIN_CHARGE, 0x40,
313 							CHARGERUSB_CTRL1);
314 	else
315 		twl6030_writeb(twl, TWL_MODULE_MAIN_CHARGE, 0x00,
316 							CHARGERUSB_CTRL1);
317 }
318 
319 static int twl6030_set_vbus(struct phy_companion *comparator, bool enabled)
320 {
321 	struct twl6030_usb *twl = comparator_to_twl(comparator);
322 
323 	twl->vbus_enable = enabled;
324 	schedule_work(&twl->set_vbus_work);
325 
326 	return 0;
327 }
328 
329 static int twl6030_usb_probe(struct platform_device *pdev)
330 {
331 	u32 ret;
332 	struct twl6030_usb	*twl;
333 	int			status, err;
334 	struct device_node	*np = pdev->dev.of_node;
335 	struct device		*dev = &pdev->dev;
336 
337 	if (!np) {
338 		dev_err(dev, "no DT info\n");
339 		return -EINVAL;
340 	}
341 
342 	twl = devm_kzalloc(dev, sizeof(*twl), GFP_KERNEL);
343 	if (!twl)
344 		return -ENOMEM;
345 
346 	twl->dev		= &pdev->dev;
347 	twl->irq1		= platform_get_irq(pdev, 0);
348 	twl->irq2		= platform_get_irq(pdev, 1);
349 	twl->linkstat		= MUSB_UNKNOWN;
350 
351 	if (twl->irq1 < 0)
352 		return twl->irq1;
353 	if (twl->irq2 < 0)
354 		return twl->irq2;
355 
356 	twl->comparator.set_vbus	= twl6030_set_vbus;
357 	twl->comparator.start_srp	= twl6030_start_srp;
358 
359 	ret = omap_usb2_set_comparator(&twl->comparator);
360 	if (ret == -ENODEV) {
361 		dev_info(&pdev->dev, "phy not ready, deferring probe");
362 		return -EPROBE_DEFER;
363 	}
364 
365 	/* init spinlock for workqueue */
366 	spin_lock_init(&twl->lock);
367 
368 	err = twl6030_usb_ldo_init(twl);
369 	if (err) {
370 		dev_err(&pdev->dev, "ldo init failed\n");
371 		return err;
372 	}
373 
374 	platform_set_drvdata(pdev, twl);
375 
376 	INIT_WORK(&twl->set_vbus_work, otg_set_vbus_work);
377 	INIT_DELAYED_WORK(&twl->get_status_work, twl6030_status_work);
378 
379 	status = request_threaded_irq(twl->irq1, NULL, twl6030_usbotg_irq,
380 			IRQF_TRIGGER_FALLING | IRQF_TRIGGER_RISING | IRQF_ONESHOT,
381 			"twl6030_usb", twl);
382 	if (status < 0) {
383 		dev_err(&pdev->dev, "can't get IRQ %d, err %d\n",
384 			twl->irq1, status);
385 		goto err_put_regulator;
386 	}
387 
388 	status = request_threaded_irq(twl->irq2, NULL, twl6030_usb_irq,
389 			IRQF_TRIGGER_FALLING | IRQF_TRIGGER_RISING | IRQF_ONESHOT,
390 			"twl6030_usb", twl);
391 	if (status < 0) {
392 		dev_err(&pdev->dev, "can't get IRQ %d, err %d\n",
393 			twl->irq2, status);
394 		goto err_free_irq1;
395 	}
396 
397 	twl->asleep = 0;
398 	twl6030_enable_irq(twl);
399 	schedule_delayed_work(&twl->get_status_work, HZ);
400 	dev_info(&pdev->dev, "Initialized TWL6030 USB module\n");
401 
402 	return 0;
403 
404 err_free_irq1:
405 	free_irq(twl->irq1, twl);
406 err_put_regulator:
407 	regulator_put(twl->usb3v3);
408 
409 	return status;
410 }
411 
412 static int twl6030_usb_remove(struct platform_device *pdev)
413 {
414 	struct twl6030_usb *twl = platform_get_drvdata(pdev);
415 
416 	cancel_delayed_work_sync(&twl->get_status_work);
417 	twl6030_interrupt_mask(TWL6030_USBOTG_INT_MASK,
418 		REG_INT_MSK_LINE_C);
419 	twl6030_interrupt_mask(TWL6030_USBOTG_INT_MASK,
420 			REG_INT_MSK_STS_C);
421 	free_irq(twl->irq1, twl);
422 	free_irq(twl->irq2, twl);
423 	regulator_put(twl->usb3v3);
424 	cancel_work_sync(&twl->set_vbus_work);
425 
426 	return 0;
427 }
428 
429 static const struct of_device_id twl6030_usb_id_table[] = {
430 	{ .compatible = "ti,twl6030-usb" },
431 	{}
432 };
433 MODULE_DEVICE_TABLE(of, twl6030_usb_id_table);
434 
435 static struct platform_driver twl6030_usb_driver = {
436 	.probe		= twl6030_usb_probe,
437 	.remove		= twl6030_usb_remove,
438 	.driver		= {
439 		.name	= "twl6030_usb",
440 		.of_match_table = of_match_ptr(twl6030_usb_id_table),
441 		.dev_groups = twl6030_groups,
442 	},
443 };
444 
445 static int __init twl6030_usb_init(void)
446 {
447 	return platform_driver_register(&twl6030_usb_driver);
448 }
449 subsys_initcall(twl6030_usb_init);
450 
451 static void __exit twl6030_usb_exit(void)
452 {
453 	platform_driver_unregister(&twl6030_usb_driver);
454 }
455 module_exit(twl6030_usb_exit);
456 
457 MODULE_ALIAS("platform:twl6030_usb");
458 MODULE_AUTHOR("Hema HK <hemahk@ti.com>");
459 MODULE_DESCRIPTION("TWL6030 USB transceiver driver");
460 MODULE_LICENSE("GPL");
461