1 /*
2  * twl6030_usb - TWL6030 USB transceiver, talking to OMAP OTG driver.
3  *
4  * Copyright (C) 2010 Texas Instruments Incorporated - http://www.ti.com
5  * This program is free software; you can redistribute it and/or modify
6  * it under the terms of the GNU General Public License as published by
7  * the Free Software Foundation; either version 2 of the License, or
8  * (at your option) any later version.
9  *
10  * Author: Hema HK <hemahk@ti.com>
11  *
12  * This program is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15  * GNU General Public License for more details.
16  *
17  * You should have received a copy of the GNU General Public License
18  * along with this program; if not, write to the Free Software
19  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
20  *
21  */
22 
23 #include <linux/module.h>
24 #include <linux/init.h>
25 #include <linux/interrupt.h>
26 #include <linux/platform_device.h>
27 #include <linux/io.h>
28 #include <linux/usb/musb-omap.h>
29 #include <linux/usb/phy_companion.h>
30 #include <linux/usb/omap_usb.h>
31 #include <linux/i2c/twl.h>
32 #include <linux/regulator/consumer.h>
33 #include <linux/err.h>
34 #include <linux/slab.h>
35 #include <linux/delay.h>
36 #include <linux/of.h>
37 
38 /* usb register definitions */
39 #define USB_VENDOR_ID_LSB		0x00
40 #define USB_VENDOR_ID_MSB		0x01
41 #define USB_PRODUCT_ID_LSB		0x02
42 #define USB_PRODUCT_ID_MSB		0x03
43 #define USB_VBUS_CTRL_SET		0x04
44 #define USB_VBUS_CTRL_CLR		0x05
45 #define USB_ID_CTRL_SET			0x06
46 #define USB_ID_CTRL_CLR			0x07
47 #define USB_VBUS_INT_SRC		0x08
48 #define USB_VBUS_INT_LATCH_SET		0x09
49 #define USB_VBUS_INT_LATCH_CLR		0x0A
50 #define USB_VBUS_INT_EN_LO_SET		0x0B
51 #define USB_VBUS_INT_EN_LO_CLR		0x0C
52 #define USB_VBUS_INT_EN_HI_SET		0x0D
53 #define USB_VBUS_INT_EN_HI_CLR		0x0E
54 #define USB_ID_INT_SRC			0x0F
55 #define USB_ID_INT_LATCH_SET		0x10
56 #define USB_ID_INT_LATCH_CLR		0x11
57 
58 #define USB_ID_INT_EN_LO_SET		0x12
59 #define USB_ID_INT_EN_LO_CLR		0x13
60 #define USB_ID_INT_EN_HI_SET		0x14
61 #define USB_ID_INT_EN_HI_CLR		0x15
62 #define USB_OTG_ADP_CTRL		0x16
63 #define USB_OTG_ADP_HIGH		0x17
64 #define USB_OTG_ADP_LOW			0x18
65 #define USB_OTG_ADP_RISE		0x19
66 #define USB_OTG_REVISION		0x1A
67 
68 /* to be moved to LDO */
69 #define TWL6030_MISC2			0xE5
70 #define TWL6030_CFG_LDO_PD2		0xF5
71 #define TWL6030_BACKUP_REG		0xFA
72 
73 #define STS_HW_CONDITIONS		0x21
74 
75 /* In module TWL6030_MODULE_PM_MASTER */
76 #define STS_HW_CONDITIONS		0x21
77 #define STS_USB_ID			BIT(2)
78 
79 /* In module TWL6030_MODULE_PM_RECEIVER */
80 #define VUSB_CFG_TRANS			0x71
81 #define VUSB_CFG_STATE			0x72
82 #define VUSB_CFG_VOLTAGE		0x73
83 
84 /* in module TWL6030_MODULE_MAIN_CHARGE */
85 
86 #define CHARGERUSB_CTRL1		0x8
87 
88 #define CONTROLLER_STAT1		0x03
89 #define	VBUS_DET			BIT(2)
90 
91 struct twl6030_usb {
92 	struct phy_companion	comparator;
93 	struct device		*dev;
94 
95 	/* for vbus reporting with irqs disabled */
96 	spinlock_t		lock;
97 
98 	struct regulator		*usb3v3;
99 
100 	/* used to set vbus, in atomic path */
101 	struct work_struct	set_vbus_work;
102 
103 	int			irq1;
104 	int			irq2;
105 	enum omap_musb_vbus_id_status linkstat;
106 	u8			asleep;
107 	bool			irq_enabled;
108 	bool			vbus_enable;
109 	const char		*regulator;
110 };
111 
112 #define	comparator_to_twl(x) container_of((x), struct twl6030_usb, comparator)
113 
114 /*-------------------------------------------------------------------------*/
115 
116 static inline int twl6030_writeb(struct twl6030_usb *twl, u8 module,
117 						u8 data, u8 address)
118 {
119 	int ret = 0;
120 
121 	ret = twl_i2c_write_u8(module, data, address);
122 	if (ret < 0)
123 		dev_err(twl->dev,
124 			"Write[0x%x] Error %d\n", address, ret);
125 	return ret;
126 }
127 
128 static inline u8 twl6030_readb(struct twl6030_usb *twl, u8 module, u8 address)
129 {
130 	u8 data, ret = 0;
131 
132 	ret = twl_i2c_read_u8(module, &data, address);
133 	if (ret >= 0)
134 		ret = data;
135 	else
136 		dev_err(twl->dev,
137 			"readb[0x%x,0x%x] Error %d\n",
138 					module, address, ret);
139 	return ret;
140 }
141 
142 static int twl6030_start_srp(struct phy_companion *comparator)
143 {
144 	struct twl6030_usb *twl = comparator_to_twl(comparator);
145 
146 	twl6030_writeb(twl, TWL_MODULE_USB, 0x24, USB_VBUS_CTRL_SET);
147 	twl6030_writeb(twl, TWL_MODULE_USB, 0x84, USB_VBUS_CTRL_SET);
148 
149 	mdelay(100);
150 	twl6030_writeb(twl, TWL_MODULE_USB, 0xa0, USB_VBUS_CTRL_CLR);
151 
152 	return 0;
153 }
154 
155 static int twl6030_usb_ldo_init(struct twl6030_usb *twl)
156 {
157 	/* Set to OTG_REV 1.3 and turn on the ID_WAKEUP_COMP */
158 	twl6030_writeb(twl, TWL6030_MODULE_ID0 , 0x1, TWL6030_BACKUP_REG);
159 
160 	/* Program CFG_LDO_PD2 register and set VUSB bit */
161 	twl6030_writeb(twl, TWL6030_MODULE_ID0 , 0x1, TWL6030_CFG_LDO_PD2);
162 
163 	/* Program MISC2 register and set bit VUSB_IN_VBAT */
164 	twl6030_writeb(twl, TWL6030_MODULE_ID0 , 0x10, TWL6030_MISC2);
165 
166 	twl->usb3v3 = regulator_get(twl->dev, twl->regulator);
167 	if (IS_ERR(twl->usb3v3))
168 		return -ENODEV;
169 
170 	/* Program the USB_VBUS_CTRL_SET and set VBUS_ACT_COMP bit */
171 	twl6030_writeb(twl, TWL_MODULE_USB, 0x4, USB_VBUS_CTRL_SET);
172 
173 	/*
174 	 * Program the USB_ID_CTRL_SET register to enable GND drive
175 	 * and the ID comparators
176 	 */
177 	twl6030_writeb(twl, TWL_MODULE_USB, 0x14, USB_ID_CTRL_SET);
178 
179 	return 0;
180 }
181 
182 static ssize_t twl6030_usb_vbus_show(struct device *dev,
183 			struct device_attribute *attr, char *buf)
184 {
185 	struct twl6030_usb *twl = dev_get_drvdata(dev);
186 	unsigned long flags;
187 	int ret = -EINVAL;
188 
189 	spin_lock_irqsave(&twl->lock, flags);
190 
191 	switch (twl->linkstat) {
192 	case OMAP_MUSB_VBUS_VALID:
193 	       ret = snprintf(buf, PAGE_SIZE, "vbus\n");
194 	       break;
195 	case OMAP_MUSB_ID_GROUND:
196 	       ret = snprintf(buf, PAGE_SIZE, "id\n");
197 	       break;
198 	case OMAP_MUSB_VBUS_OFF:
199 	       ret = snprintf(buf, PAGE_SIZE, "none\n");
200 	       break;
201 	default:
202 	       ret = snprintf(buf, PAGE_SIZE, "UNKNOWN\n");
203 	}
204 	spin_unlock_irqrestore(&twl->lock, flags);
205 
206 	return ret;
207 }
208 static DEVICE_ATTR(vbus, 0444, twl6030_usb_vbus_show, NULL);
209 
210 static irqreturn_t twl6030_usb_irq(int irq, void *_twl)
211 {
212 	struct twl6030_usb *twl = _twl;
213 	enum omap_musb_vbus_id_status status = OMAP_MUSB_UNKNOWN;
214 	u8 vbus_state, hw_state;
215 	int ret;
216 
217 	hw_state = twl6030_readb(twl, TWL6030_MODULE_ID0, STS_HW_CONDITIONS);
218 
219 	vbus_state = twl6030_readb(twl, TWL_MODULE_MAIN_CHARGE,
220 						CONTROLLER_STAT1);
221 	if (!(hw_state & STS_USB_ID)) {
222 		if (vbus_state & VBUS_DET) {
223 			ret = regulator_enable(twl->usb3v3);
224 			if (ret)
225 				dev_err(twl->dev, "Failed to enable usb3v3\n");
226 
227 			twl->asleep = 1;
228 			status = OMAP_MUSB_VBUS_VALID;
229 			twl->linkstat = status;
230 			omap_musb_mailbox(status);
231 		} else {
232 			if (twl->linkstat != OMAP_MUSB_UNKNOWN) {
233 				status = OMAP_MUSB_VBUS_OFF;
234 				twl->linkstat = status;
235 				omap_musb_mailbox(status);
236 				if (twl->asleep) {
237 					regulator_disable(twl->usb3v3);
238 					twl->asleep = 0;
239 				}
240 			}
241 		}
242 	}
243 	sysfs_notify(&twl->dev->kobj, NULL, "vbus");
244 
245 	return IRQ_HANDLED;
246 }
247 
248 static irqreturn_t twl6030_usbotg_irq(int irq, void *_twl)
249 {
250 	struct twl6030_usb *twl = _twl;
251 	enum omap_musb_vbus_id_status status = OMAP_MUSB_UNKNOWN;
252 	u8 hw_state;
253 	int ret;
254 
255 	hw_state = twl6030_readb(twl, TWL6030_MODULE_ID0, STS_HW_CONDITIONS);
256 
257 	if (hw_state & STS_USB_ID) {
258 		ret = regulator_enable(twl->usb3v3);
259 		if (ret)
260 			dev_err(twl->dev, "Failed to enable usb3v3\n");
261 
262 		twl->asleep = 1;
263 		twl6030_writeb(twl, TWL_MODULE_USB, 0x1, USB_ID_INT_EN_HI_CLR);
264 		twl6030_writeb(twl, TWL_MODULE_USB, 0x10, USB_ID_INT_EN_HI_SET);
265 		status = OMAP_MUSB_ID_GROUND;
266 		twl->linkstat = status;
267 		omap_musb_mailbox(status);
268 	} else  {
269 		twl6030_writeb(twl, TWL_MODULE_USB, 0x10, USB_ID_INT_EN_HI_CLR);
270 		twl6030_writeb(twl, TWL_MODULE_USB, 0x1, USB_ID_INT_EN_HI_SET);
271 	}
272 	twl6030_writeb(twl, TWL_MODULE_USB, status, USB_ID_INT_LATCH_CLR);
273 
274 	return IRQ_HANDLED;
275 }
276 
277 static int twl6030_enable_irq(struct twl6030_usb *twl)
278 {
279 	twl6030_writeb(twl, TWL_MODULE_USB, 0x1, USB_ID_INT_EN_HI_SET);
280 	twl6030_interrupt_unmask(0x05, REG_INT_MSK_LINE_C);
281 	twl6030_interrupt_unmask(0x05, REG_INT_MSK_STS_C);
282 
283 	twl6030_interrupt_unmask(TWL6030_CHARGER_CTRL_INT_MASK,
284 				REG_INT_MSK_LINE_C);
285 	twl6030_interrupt_unmask(TWL6030_CHARGER_CTRL_INT_MASK,
286 				REG_INT_MSK_STS_C);
287 	twl6030_usb_irq(twl->irq2, twl);
288 	twl6030_usbotg_irq(twl->irq1, twl);
289 
290 	return 0;
291 }
292 
293 static void otg_set_vbus_work(struct work_struct *data)
294 {
295 	struct twl6030_usb *twl = container_of(data, struct twl6030_usb,
296 								set_vbus_work);
297 
298 	/*
299 	 * Start driving VBUS. Set OPA_MODE bit in CHARGERUSB_CTRL1
300 	 * register. This enables boost mode.
301 	 */
302 
303 	if (twl->vbus_enable)
304 		twl6030_writeb(twl, TWL_MODULE_MAIN_CHARGE , 0x40,
305 							CHARGERUSB_CTRL1);
306 	else
307 		twl6030_writeb(twl, TWL_MODULE_MAIN_CHARGE , 0x00,
308 							CHARGERUSB_CTRL1);
309 }
310 
311 static int twl6030_set_vbus(struct phy_companion *comparator, bool enabled)
312 {
313 	struct twl6030_usb *twl = comparator_to_twl(comparator);
314 
315 	twl->vbus_enable = enabled;
316 	schedule_work(&twl->set_vbus_work);
317 
318 	return 0;
319 }
320 
321 static int twl6030_usb_probe(struct platform_device *pdev)
322 {
323 	u32 ret;
324 	struct twl6030_usb	*twl;
325 	int			status, err;
326 	struct device_node	*np = pdev->dev.of_node;
327 	struct device		*dev = &pdev->dev;
328 	struct twl4030_usb_data	*pdata = dev_get_platdata(dev);
329 
330 	twl = devm_kzalloc(dev, sizeof *twl, GFP_KERNEL);
331 	if (!twl)
332 		return -ENOMEM;
333 
334 	twl->dev		= &pdev->dev;
335 	twl->irq1		= platform_get_irq(pdev, 0);
336 	twl->irq2		= platform_get_irq(pdev, 1);
337 	twl->linkstat		= OMAP_MUSB_UNKNOWN;
338 
339 	twl->comparator.set_vbus	= twl6030_set_vbus;
340 	twl->comparator.start_srp	= twl6030_start_srp;
341 
342 	ret = omap_usb2_set_comparator(&twl->comparator);
343 	if (ret == -ENODEV) {
344 		dev_info(&pdev->dev, "phy not ready, deferring probe");
345 		return -EPROBE_DEFER;
346 	}
347 
348 	if (np) {
349 		twl->regulator = "usb";
350 	} else if (pdata) {
351 		if (pdata->features & TWL6032_SUBCLASS)
352 			twl->regulator = "ldousb";
353 		else
354 			twl->regulator = "vusb";
355 	} else {
356 		dev_err(&pdev->dev, "twl6030 initialized without pdata\n");
357 		return -EINVAL;
358 	}
359 
360 	/* init spinlock for workqueue */
361 	spin_lock_init(&twl->lock);
362 
363 	err = twl6030_usb_ldo_init(twl);
364 	if (err) {
365 		dev_err(&pdev->dev, "ldo init failed\n");
366 		return err;
367 	}
368 
369 	platform_set_drvdata(pdev, twl);
370 	if (device_create_file(&pdev->dev, &dev_attr_vbus))
371 		dev_warn(&pdev->dev, "could not create sysfs file\n");
372 
373 	INIT_WORK(&twl->set_vbus_work, otg_set_vbus_work);
374 
375 	twl->irq_enabled = true;
376 	status = request_threaded_irq(twl->irq1, NULL, twl6030_usbotg_irq,
377 			IRQF_TRIGGER_FALLING | IRQF_TRIGGER_RISING | IRQF_ONESHOT,
378 			"twl6030_usb", twl);
379 	if (status < 0) {
380 		dev_err(&pdev->dev, "can't get IRQ %d, err %d\n",
381 			twl->irq1, status);
382 		device_remove_file(twl->dev, &dev_attr_vbus);
383 		return status;
384 	}
385 
386 	status = request_threaded_irq(twl->irq2, NULL, twl6030_usb_irq,
387 			IRQF_TRIGGER_FALLING | IRQF_TRIGGER_RISING | IRQF_ONESHOT,
388 			"twl6030_usb", twl);
389 	if (status < 0) {
390 		dev_err(&pdev->dev, "can't get IRQ %d, err %d\n",
391 			twl->irq2, status);
392 		free_irq(twl->irq1, twl);
393 		device_remove_file(twl->dev, &dev_attr_vbus);
394 		return status;
395 	}
396 
397 	twl->asleep = 0;
398 	twl6030_enable_irq(twl);
399 	dev_info(&pdev->dev, "Initialized TWL6030 USB module\n");
400 
401 	return 0;
402 }
403 
404 static int twl6030_usb_remove(struct platform_device *pdev)
405 {
406 	struct twl6030_usb *twl = platform_get_drvdata(pdev);
407 
408 	twl6030_interrupt_mask(TWL6030_USBOTG_INT_MASK,
409 		REG_INT_MSK_LINE_C);
410 	twl6030_interrupt_mask(TWL6030_USBOTG_INT_MASK,
411 			REG_INT_MSK_STS_C);
412 	free_irq(twl->irq1, twl);
413 	free_irq(twl->irq2, twl);
414 	regulator_put(twl->usb3v3);
415 	device_remove_file(twl->dev, &dev_attr_vbus);
416 	cancel_work_sync(&twl->set_vbus_work);
417 
418 	return 0;
419 }
420 
421 #ifdef CONFIG_OF
422 static const struct of_device_id twl6030_usb_id_table[] = {
423 	{ .compatible = "ti,twl6030-usb" },
424 	{}
425 };
426 MODULE_DEVICE_TABLE(of, twl6030_usb_id_table);
427 #endif
428 
429 static struct platform_driver twl6030_usb_driver = {
430 	.probe		= twl6030_usb_probe,
431 	.remove		= twl6030_usb_remove,
432 	.driver		= {
433 		.name	= "twl6030_usb",
434 		.owner	= THIS_MODULE,
435 		.of_match_table = of_match_ptr(twl6030_usb_id_table),
436 	},
437 };
438 
439 static int __init twl6030_usb_init(void)
440 {
441 	return platform_driver_register(&twl6030_usb_driver);
442 }
443 subsys_initcall(twl6030_usb_init);
444 
445 static void __exit twl6030_usb_exit(void)
446 {
447 	platform_driver_unregister(&twl6030_usb_driver);
448 }
449 module_exit(twl6030_usb_exit);
450 
451 MODULE_ALIAS("platform:twl6030_usb");
452 MODULE_AUTHOR("Hema HK <hemahk@ti.com>");
453 MODULE_DESCRIPTION("TWL6030 USB transceiver driver");
454 MODULE_LICENSE("GPL");
455