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 - http://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 irqreturn_t twl6030_usb_irq(int irq, void *_twl)
200 {
201 	struct twl6030_usb *twl = _twl;
202 	enum musb_vbus_id_status status = MUSB_UNKNOWN;
203 	u8 vbus_state, hw_state;
204 	int ret;
205 
206 	hw_state = twl6030_readb(twl, TWL6030_MODULE_ID0, STS_HW_CONDITIONS);
207 
208 	vbus_state = twl6030_readb(twl, TWL_MODULE_MAIN_CHARGE,
209 						CONTROLLER_STAT1);
210 	if (!(hw_state & STS_USB_ID)) {
211 		if (vbus_state & VBUS_DET) {
212 			ret = regulator_enable(twl->usb3v3);
213 			if (ret)
214 				dev_err(twl->dev, "Failed to enable usb3v3\n");
215 
216 			twl->asleep = 1;
217 			status = MUSB_VBUS_VALID;
218 			twl->linkstat = status;
219 			ret = musb_mailbox(status);
220 			if (ret)
221 				twl->linkstat = MUSB_UNKNOWN;
222 		} else {
223 			if (twl->linkstat != MUSB_UNKNOWN) {
224 				status = MUSB_VBUS_OFF;
225 				twl->linkstat = status;
226 				ret = musb_mailbox(status);
227 				if (ret)
228 					twl->linkstat = MUSB_UNKNOWN;
229 				if (twl->asleep) {
230 					regulator_disable(twl->usb3v3);
231 					twl->asleep = 0;
232 				}
233 			}
234 		}
235 	}
236 	sysfs_notify(&twl->dev->kobj, NULL, "vbus");
237 
238 	return IRQ_HANDLED;
239 }
240 
241 static irqreturn_t twl6030_usbotg_irq(int irq, void *_twl)
242 {
243 	struct twl6030_usb *twl = _twl;
244 	enum musb_vbus_id_status status = MUSB_UNKNOWN;
245 	u8 hw_state;
246 	int ret;
247 
248 	hw_state = twl6030_readb(twl, TWL6030_MODULE_ID0, STS_HW_CONDITIONS);
249 
250 	if (hw_state & STS_USB_ID) {
251 		ret = regulator_enable(twl->usb3v3);
252 		if (ret)
253 			dev_err(twl->dev, "Failed to enable usb3v3\n");
254 
255 		twl->asleep = 1;
256 		twl6030_writeb(twl, TWL_MODULE_USB, 0x1, USB_ID_INT_EN_HI_CLR);
257 		twl6030_writeb(twl, TWL_MODULE_USB, 0x10, USB_ID_INT_EN_HI_SET);
258 		status = MUSB_ID_GROUND;
259 		twl->linkstat = status;
260 		ret = musb_mailbox(status);
261 		if (ret)
262 			twl->linkstat = MUSB_UNKNOWN;
263 	} else  {
264 		twl6030_writeb(twl, TWL_MODULE_USB, 0x10, USB_ID_INT_EN_HI_CLR);
265 		twl6030_writeb(twl, TWL_MODULE_USB, 0x1, USB_ID_INT_EN_HI_SET);
266 	}
267 	twl6030_writeb(twl, TWL_MODULE_USB, status, USB_ID_INT_LATCH_CLR);
268 
269 	return IRQ_HANDLED;
270 }
271 
272 static void twl6030_status_work(struct work_struct *work)
273 {
274 	struct twl6030_usb *twl = container_of(work, struct twl6030_usb,
275 					       get_status_work.work);
276 
277 	twl6030_usb_irq(twl->irq2, twl);
278 	twl6030_usbotg_irq(twl->irq1, twl);
279 }
280 
281 static int twl6030_enable_irq(struct twl6030_usb *twl)
282 {
283 	twl6030_writeb(twl, TWL_MODULE_USB, 0x1, USB_ID_INT_EN_HI_SET);
284 	twl6030_interrupt_unmask(0x05, REG_INT_MSK_LINE_C);
285 	twl6030_interrupt_unmask(0x05, REG_INT_MSK_STS_C);
286 
287 	twl6030_interrupt_unmask(TWL6030_CHARGER_CTRL_INT_MASK,
288 				REG_INT_MSK_LINE_C);
289 	twl6030_interrupt_unmask(TWL6030_CHARGER_CTRL_INT_MASK,
290 				REG_INT_MSK_STS_C);
291 
292 	return 0;
293 }
294 
295 static void otg_set_vbus_work(struct work_struct *data)
296 {
297 	struct twl6030_usb *twl = container_of(data, struct twl6030_usb,
298 								set_vbus_work);
299 
300 	/*
301 	 * Start driving VBUS. Set OPA_MODE bit in CHARGERUSB_CTRL1
302 	 * register. This enables boost mode.
303 	 */
304 
305 	if (twl->vbus_enable)
306 		twl6030_writeb(twl, TWL_MODULE_MAIN_CHARGE, 0x40,
307 							CHARGERUSB_CTRL1);
308 	else
309 		twl6030_writeb(twl, TWL_MODULE_MAIN_CHARGE, 0x00,
310 							CHARGERUSB_CTRL1);
311 }
312 
313 static int twl6030_set_vbus(struct phy_companion *comparator, bool enabled)
314 {
315 	struct twl6030_usb *twl = comparator_to_twl(comparator);
316 
317 	twl->vbus_enable = enabled;
318 	schedule_work(&twl->set_vbus_work);
319 
320 	return 0;
321 }
322 
323 static int twl6030_usb_probe(struct platform_device *pdev)
324 {
325 	u32 ret;
326 	struct twl6030_usb	*twl;
327 	int			status, err;
328 	struct device_node	*np = pdev->dev.of_node;
329 	struct device		*dev = &pdev->dev;
330 
331 	if (!np) {
332 		dev_err(dev, "no DT info\n");
333 		return -EINVAL;
334 	}
335 
336 	twl = devm_kzalloc(dev, sizeof(*twl), GFP_KERNEL);
337 	if (!twl)
338 		return -ENOMEM;
339 
340 	twl->dev		= &pdev->dev;
341 	twl->irq1		= platform_get_irq(pdev, 0);
342 	twl->irq2		= platform_get_irq(pdev, 1);
343 	twl->linkstat		= MUSB_UNKNOWN;
344 
345 	twl->comparator.set_vbus	= twl6030_set_vbus;
346 	twl->comparator.start_srp	= twl6030_start_srp;
347 
348 	ret = omap_usb2_set_comparator(&twl->comparator);
349 	if (ret == -ENODEV) {
350 		dev_info(&pdev->dev, "phy not ready, deferring probe");
351 		return -EPROBE_DEFER;
352 	}
353 
354 	/* init spinlock for workqueue */
355 	spin_lock_init(&twl->lock);
356 
357 	err = twl6030_usb_ldo_init(twl);
358 	if (err) {
359 		dev_err(&pdev->dev, "ldo init failed\n");
360 		return err;
361 	}
362 
363 	platform_set_drvdata(pdev, twl);
364 	if (device_create_file(&pdev->dev, &dev_attr_vbus))
365 		dev_warn(&pdev->dev, "could not create sysfs file\n");
366 
367 	INIT_WORK(&twl->set_vbus_work, otg_set_vbus_work);
368 	INIT_DELAYED_WORK(&twl->get_status_work, twl6030_status_work);
369 
370 	status = request_threaded_irq(twl->irq1, NULL, twl6030_usbotg_irq,
371 			IRQF_TRIGGER_FALLING | IRQF_TRIGGER_RISING | IRQF_ONESHOT,
372 			"twl6030_usb", twl);
373 	if (status < 0) {
374 		dev_err(&pdev->dev, "can't get IRQ %d, err %d\n",
375 			twl->irq1, status);
376 		device_remove_file(twl->dev, &dev_attr_vbus);
377 		return status;
378 	}
379 
380 	status = request_threaded_irq(twl->irq2, NULL, twl6030_usb_irq,
381 			IRQF_TRIGGER_FALLING | IRQF_TRIGGER_RISING | IRQF_ONESHOT,
382 			"twl6030_usb", twl);
383 	if (status < 0) {
384 		dev_err(&pdev->dev, "can't get IRQ %d, err %d\n",
385 			twl->irq2, status);
386 		free_irq(twl->irq1, twl);
387 		device_remove_file(twl->dev, &dev_attr_vbus);
388 		return status;
389 	}
390 
391 	twl->asleep = 0;
392 	twl6030_enable_irq(twl);
393 	schedule_delayed_work(&twl->get_status_work, HZ);
394 	dev_info(&pdev->dev, "Initialized TWL6030 USB module\n");
395 
396 	return 0;
397 }
398 
399 static int twl6030_usb_remove(struct platform_device *pdev)
400 {
401 	struct twl6030_usb *twl = platform_get_drvdata(pdev);
402 
403 	cancel_delayed_work_sync(&twl->get_status_work);
404 	twl6030_interrupt_mask(TWL6030_USBOTG_INT_MASK,
405 		REG_INT_MSK_LINE_C);
406 	twl6030_interrupt_mask(TWL6030_USBOTG_INT_MASK,
407 			REG_INT_MSK_STS_C);
408 	free_irq(twl->irq1, twl);
409 	free_irq(twl->irq2, twl);
410 	regulator_put(twl->usb3v3);
411 	device_remove_file(twl->dev, &dev_attr_vbus);
412 	cancel_work_sync(&twl->set_vbus_work);
413 
414 	return 0;
415 }
416 
417 static const struct of_device_id twl6030_usb_id_table[] = {
418 	{ .compatible = "ti,twl6030-usb" },
419 	{}
420 };
421 MODULE_DEVICE_TABLE(of, twl6030_usb_id_table);
422 
423 static struct platform_driver twl6030_usb_driver = {
424 	.probe		= twl6030_usb_probe,
425 	.remove		= twl6030_usb_remove,
426 	.driver		= {
427 		.name	= "twl6030_usb",
428 		.of_match_table = of_match_ptr(twl6030_usb_id_table),
429 	},
430 };
431 
432 static int __init twl6030_usb_init(void)
433 {
434 	return platform_driver_register(&twl6030_usb_driver);
435 }
436 subsys_initcall(twl6030_usb_init);
437 
438 static void __exit twl6030_usb_exit(void)
439 {
440 	platform_driver_unregister(&twl6030_usb_driver);
441 }
442 module_exit(twl6030_usb_exit);
443 
444 MODULE_ALIAS("platform:twl6030_usb");
445 MODULE_AUTHOR("Hema HK <hemahk@ti.com>");
446 MODULE_DESCRIPTION("TWL6030 USB transceiver driver");
447 MODULE_LICENSE("GPL");
448