xref: /openbmc/linux/drivers/w1/masters/omap_hdq.c (revision 78560d41)
1 /*
2  * drivers/w1/masters/omap_hdq.c
3  *
4  * Copyright (C) 2007,2012 Texas Instruments, Inc.
5  *
6  * This file is licensed under the terms of the GNU General Public License
7  * version 2. This program is licensed "as is" without any warranty of any
8  * kind, whether express or implied.
9  *
10  */
11 #include <linux/kernel.h>
12 #include <linux/module.h>
13 #include <linux/platform_device.h>
14 #include <linux/interrupt.h>
15 #include <linux/slab.h>
16 #include <linux/err.h>
17 #include <linux/io.h>
18 #include <linux/sched.h>
19 #include <linux/pm_runtime.h>
20 #include <linux/of.h>
21 
22 #include <linux/w1.h>
23 
24 #define	MOD_NAME	"OMAP_HDQ:"
25 
26 #define OMAP_HDQ_REVISION			0x00
27 #define OMAP_HDQ_TX_DATA			0x04
28 #define OMAP_HDQ_RX_DATA			0x08
29 #define OMAP_HDQ_CTRL_STATUS			0x0c
30 #define OMAP_HDQ_CTRL_STATUS_SINGLE		BIT(7)
31 #define OMAP_HDQ_CTRL_STATUS_INTERRUPTMASK	BIT(6)
32 #define OMAP_HDQ_CTRL_STATUS_CLOCKENABLE	BIT(5)
33 #define OMAP_HDQ_CTRL_STATUS_GO                 BIT(4)
34 #define OMAP_HDQ_CTRL_STATUS_PRESENCE		BIT(3)
35 #define OMAP_HDQ_CTRL_STATUS_INITIALIZATION	BIT(2)
36 #define OMAP_HDQ_CTRL_STATUS_DIR		BIT(1)
37 #define OMAP_HDQ_INT_STATUS			0x10
38 #define OMAP_HDQ_INT_STATUS_TXCOMPLETE		BIT(2)
39 #define OMAP_HDQ_INT_STATUS_RXCOMPLETE		BIT(1)
40 #define OMAP_HDQ_INT_STATUS_TIMEOUT		BIT(0)
41 
42 #define OMAP_HDQ_FLAG_CLEAR			0
43 #define OMAP_HDQ_FLAG_SET			1
44 #define OMAP_HDQ_TIMEOUT			(HZ/5)
45 
46 #define OMAP_HDQ_MAX_USER			4
47 
48 static DECLARE_WAIT_QUEUE_HEAD(hdq_wait_queue);
49 
50 static int w1_id;
51 module_param(w1_id, int, S_IRUSR);
52 MODULE_PARM_DESC(w1_id, "1-wire id for the slave detection in HDQ mode");
53 
54 struct hdq_data {
55 	struct device		*dev;
56 	void __iomem		*hdq_base;
57 	/* lock status update */
58 	struct  mutex		hdq_mutex;
59 	u8			hdq_irqstatus;
60 	/* device lock */
61 	spinlock_t		hdq_spinlock;
62 	/* mode: 0-HDQ 1-W1 */
63 	int                     mode;
64 
65 };
66 
67 /* HDQ register I/O routines */
68 static inline u8 hdq_reg_in(struct hdq_data *hdq_data, u32 offset)
69 {
70 	return __raw_readl(hdq_data->hdq_base + offset);
71 }
72 
73 static inline void hdq_reg_out(struct hdq_data *hdq_data, u32 offset, u8 val)
74 {
75 	__raw_writel(val, hdq_data->hdq_base + offset);
76 }
77 
78 static inline u8 hdq_reg_merge(struct hdq_data *hdq_data, u32 offset,
79 			u8 val, u8 mask)
80 {
81 	u8 new_val = (__raw_readl(hdq_data->hdq_base + offset) & ~mask)
82 			| (val & mask);
83 	__raw_writel(new_val, hdq_data->hdq_base + offset);
84 
85 	return new_val;
86 }
87 
88 /*
89  * Wait for one or more bits in flag change.
90  * HDQ_FLAG_SET: wait until any bit in the flag is set.
91  * HDQ_FLAG_CLEAR: wait until all bits in the flag are cleared.
92  * return 0 on success and -ETIMEDOUT in the case of timeout.
93  */
94 static int hdq_wait_for_flag(struct hdq_data *hdq_data, u32 offset,
95 		u8 flag, u8 flag_set, u8 *status)
96 {
97 	int ret = 0;
98 	unsigned long timeout = jiffies + OMAP_HDQ_TIMEOUT;
99 
100 	if (flag_set == OMAP_HDQ_FLAG_CLEAR) {
101 		/* wait for the flag clear */
102 		while (((*status = hdq_reg_in(hdq_data, offset)) & flag)
103 			&& time_before(jiffies, timeout)) {
104 			schedule_timeout_uninterruptible(1);
105 		}
106 		if (*status & flag)
107 			ret = -ETIMEDOUT;
108 	} else if (flag_set == OMAP_HDQ_FLAG_SET) {
109 		/* wait for the flag set */
110 		while (!((*status = hdq_reg_in(hdq_data, offset)) & flag)
111 			&& time_before(jiffies, timeout)) {
112 			schedule_timeout_uninterruptible(1);
113 		}
114 		if (!(*status & flag))
115 			ret = -ETIMEDOUT;
116 	} else
117 		return -EINVAL;
118 
119 	return ret;
120 }
121 
122 /* Clear saved irqstatus after using an interrupt */
123 static void hdq_reset_irqstatus(struct hdq_data *hdq_data)
124 {
125 	unsigned long irqflags;
126 
127 	spin_lock_irqsave(&hdq_data->hdq_spinlock, irqflags);
128 	hdq_data->hdq_irqstatus = 0;
129 	spin_unlock_irqrestore(&hdq_data->hdq_spinlock, irqflags);
130 }
131 
132 /* write out a byte and fill *status with HDQ_INT_STATUS */
133 static int hdq_write_byte(struct hdq_data *hdq_data, u8 val, u8 *status)
134 {
135 	int ret;
136 	u8 tmp_status;
137 
138 	*status = 0;
139 
140 	hdq_reg_out(hdq_data, OMAP_HDQ_TX_DATA, val);
141 
142 	/* set the GO bit */
143 	hdq_reg_merge(hdq_data, OMAP_HDQ_CTRL_STATUS, OMAP_HDQ_CTRL_STATUS_GO,
144 		OMAP_HDQ_CTRL_STATUS_DIR | OMAP_HDQ_CTRL_STATUS_GO);
145 	/* wait for the TXCOMPLETE bit */
146 	ret = wait_event_timeout(hdq_wait_queue,
147 		hdq_data->hdq_irqstatus, OMAP_HDQ_TIMEOUT);
148 	if (ret == 0) {
149 		dev_dbg(hdq_data->dev, "TX wait elapsed\n");
150 		ret = -ETIMEDOUT;
151 		goto out;
152 	}
153 
154 	*status = hdq_data->hdq_irqstatus;
155 	/* check irqstatus */
156 	if (!(*status & OMAP_HDQ_INT_STATUS_TXCOMPLETE)) {
157 		dev_dbg(hdq_data->dev, "timeout waiting for"
158 			" TXCOMPLETE/RXCOMPLETE, %x", *status);
159 		ret = -ETIMEDOUT;
160 		goto out;
161 	}
162 
163 	/* wait for the GO bit return to zero */
164 	ret = hdq_wait_for_flag(hdq_data, OMAP_HDQ_CTRL_STATUS,
165 			OMAP_HDQ_CTRL_STATUS_GO,
166 			OMAP_HDQ_FLAG_CLEAR, &tmp_status);
167 	if (ret) {
168 		dev_dbg(hdq_data->dev, "timeout waiting GO bit"
169 			" return to zero, %x", tmp_status);
170 	}
171 
172 out:
173 	hdq_reset_irqstatus(hdq_data);
174 	return ret;
175 }
176 
177 /* HDQ Interrupt service routine */
178 static irqreturn_t hdq_isr(int irq, void *_hdq)
179 {
180 	struct hdq_data *hdq_data = _hdq;
181 	unsigned long irqflags;
182 
183 	spin_lock_irqsave(&hdq_data->hdq_spinlock, irqflags);
184 	hdq_data->hdq_irqstatus = hdq_reg_in(hdq_data, OMAP_HDQ_INT_STATUS);
185 	spin_unlock_irqrestore(&hdq_data->hdq_spinlock, irqflags);
186 	dev_dbg(hdq_data->dev, "hdq_isr: %x", hdq_data->hdq_irqstatus);
187 
188 	if (hdq_data->hdq_irqstatus &
189 		(OMAP_HDQ_INT_STATUS_TXCOMPLETE | OMAP_HDQ_INT_STATUS_RXCOMPLETE
190 		| OMAP_HDQ_INT_STATUS_TIMEOUT)) {
191 		/* wake up sleeping process */
192 		wake_up(&hdq_wait_queue);
193 	}
194 
195 	return IRQ_HANDLED;
196 }
197 
198 /* W1 search callback function  in HDQ mode */
199 static void omap_w1_search_bus(void *_hdq, struct w1_master *master_dev,
200 		u8 search_type, w1_slave_found_callback slave_found)
201 {
202 	u64 module_id, rn_le, cs, id;
203 
204 	if (w1_id)
205 		module_id = w1_id;
206 	else
207 		module_id = 0x1;
208 
209 	rn_le = cpu_to_le64(module_id);
210 	/*
211 	 * HDQ might not obey truly the 1-wire spec.
212 	 * So calculate CRC based on module parameter.
213 	 */
214 	cs = w1_calc_crc8((u8 *)&rn_le, 7);
215 	id = (cs << 56) | module_id;
216 
217 	slave_found(master_dev, id);
218 }
219 
220 /* Issue break pulse to the device */
221 static int omap_hdq_break(struct hdq_data *hdq_data)
222 {
223 	int ret = 0;
224 	u8 tmp_status;
225 
226 	ret = mutex_lock_interruptible(&hdq_data->hdq_mutex);
227 	if (ret < 0) {
228 		dev_dbg(hdq_data->dev, "Could not acquire mutex\n");
229 		ret = -EINTR;
230 		goto rtn;
231 	}
232 
233 	/* set the INIT and GO bit */
234 	hdq_reg_merge(hdq_data, OMAP_HDQ_CTRL_STATUS,
235 		OMAP_HDQ_CTRL_STATUS_INITIALIZATION | OMAP_HDQ_CTRL_STATUS_GO,
236 		OMAP_HDQ_CTRL_STATUS_DIR | OMAP_HDQ_CTRL_STATUS_INITIALIZATION |
237 		OMAP_HDQ_CTRL_STATUS_GO);
238 
239 	/* wait for the TIMEOUT bit */
240 	ret = wait_event_timeout(hdq_wait_queue,
241 		hdq_data->hdq_irqstatus, OMAP_HDQ_TIMEOUT);
242 	if (ret == 0) {
243 		dev_dbg(hdq_data->dev, "break wait elapsed\n");
244 		ret = -EINTR;
245 		goto out;
246 	}
247 
248 	tmp_status = hdq_data->hdq_irqstatus;
249 	/* check irqstatus */
250 	if (!(tmp_status & OMAP_HDQ_INT_STATUS_TIMEOUT)) {
251 		dev_dbg(hdq_data->dev, "timeout waiting for TIMEOUT, %x",
252 				tmp_status);
253 		ret = -ETIMEDOUT;
254 		goto out;
255 	}
256 
257 	/*
258 	 * check for the presence detect bit to get
259 	 * set to show that the slave is responding
260 	 */
261 	if (!(hdq_reg_in(hdq_data, OMAP_HDQ_CTRL_STATUS) &
262 			OMAP_HDQ_CTRL_STATUS_PRESENCE)) {
263 		dev_dbg(hdq_data->dev, "Presence bit not set\n");
264 		ret = -ETIMEDOUT;
265 		goto out;
266 	}
267 
268 	/*
269 	 * wait for both INIT and GO bits rerurn to zero.
270 	 * zero wait time expected for interrupt mode.
271 	 */
272 	ret = hdq_wait_for_flag(hdq_data, OMAP_HDQ_CTRL_STATUS,
273 			OMAP_HDQ_CTRL_STATUS_INITIALIZATION |
274 			OMAP_HDQ_CTRL_STATUS_GO, OMAP_HDQ_FLAG_CLEAR,
275 			&tmp_status);
276 	if (ret)
277 		dev_dbg(hdq_data->dev, "timeout waiting INIT&GO bits"
278 			" return to zero, %x", tmp_status);
279 
280 out:
281 	hdq_reset_irqstatus(hdq_data);
282 	mutex_unlock(&hdq_data->hdq_mutex);
283 rtn:
284 	return ret;
285 }
286 
287 static int hdq_read_byte(struct hdq_data *hdq_data, u8 *val)
288 {
289 	int ret = 0;
290 	u8 status;
291 
292 	ret = mutex_lock_interruptible(&hdq_data->hdq_mutex);
293 	if (ret < 0) {
294 		ret = -EINTR;
295 		goto rtn;
296 	}
297 
298 	if (pm_runtime_suspended(hdq_data->dev)) {
299 		ret = -EINVAL;
300 		goto out;
301 	}
302 
303 	if (!(hdq_data->hdq_irqstatus & OMAP_HDQ_INT_STATUS_RXCOMPLETE)) {
304 		hdq_reg_merge(hdq_data, OMAP_HDQ_CTRL_STATUS,
305 			OMAP_HDQ_CTRL_STATUS_DIR | OMAP_HDQ_CTRL_STATUS_GO,
306 			OMAP_HDQ_CTRL_STATUS_DIR | OMAP_HDQ_CTRL_STATUS_GO);
307 		/*
308 		 * The RX comes immediately after TX.
309 		 */
310 		wait_event_timeout(hdq_wait_queue,
311 				   (hdq_data->hdq_irqstatus
312 				    & OMAP_HDQ_INT_STATUS_RXCOMPLETE),
313 				   OMAP_HDQ_TIMEOUT);
314 
315 		hdq_reg_merge(hdq_data, OMAP_HDQ_CTRL_STATUS, 0,
316 			OMAP_HDQ_CTRL_STATUS_DIR);
317 		status = hdq_data->hdq_irqstatus;
318 		/* check irqstatus */
319 		if (!(status & OMAP_HDQ_INT_STATUS_RXCOMPLETE)) {
320 			dev_dbg(hdq_data->dev, "timeout waiting for"
321 				" RXCOMPLETE, %x", status);
322 			ret = -ETIMEDOUT;
323 			goto out;
324 		}
325 	}
326 	/* the data is ready. Read it in! */
327 	*val = hdq_reg_in(hdq_data, OMAP_HDQ_RX_DATA);
328 out:
329 	hdq_reset_irqstatus(hdq_data);
330 	mutex_unlock(&hdq_data->hdq_mutex);
331 rtn:
332 	return ret;
333 
334 }
335 
336 /*
337  * W1 triplet callback function - used for searching ROM addresses.
338  * Registered only when controller is in 1-wire mode.
339  */
340 static u8 omap_w1_triplet(void *_hdq, u8 bdir)
341 {
342 	u8 id_bit, comp_bit;
343 	int err;
344 	u8 ret = 0x3; /* no slaves responded */
345 	struct hdq_data *hdq_data = _hdq;
346 	u8 ctrl = OMAP_HDQ_CTRL_STATUS_SINGLE | OMAP_HDQ_CTRL_STATUS_GO |
347 		  OMAP_HDQ_CTRL_STATUS_INTERRUPTMASK;
348 	u8 mask = ctrl | OMAP_HDQ_CTRL_STATUS_DIR;
349 
350 	err = pm_runtime_get_sync(hdq_data->dev);
351 	if (err < 0) {
352 		pm_runtime_put_noidle(hdq_data->dev);
353 
354 		return err;
355 	}
356 
357 	err = mutex_lock_interruptible(&hdq_data->hdq_mutex);
358 	if (err < 0) {
359 		dev_dbg(hdq_data->dev, "Could not acquire mutex\n");
360 		goto rtn;
361 	}
362 
363 	/* read id_bit */
364 	hdq_reg_merge(_hdq, OMAP_HDQ_CTRL_STATUS,
365 		      ctrl | OMAP_HDQ_CTRL_STATUS_DIR, mask);
366 	err = wait_event_timeout(hdq_wait_queue,
367 				 (hdq_data->hdq_irqstatus
368 				  & OMAP_HDQ_INT_STATUS_RXCOMPLETE),
369 				 OMAP_HDQ_TIMEOUT);
370 	if (err == 0) {
371 		dev_dbg(hdq_data->dev, "RX wait elapsed\n");
372 		goto out;
373 	}
374 	id_bit = (hdq_reg_in(_hdq, OMAP_HDQ_RX_DATA) & 0x01);
375 
376 	/* Must clear irqstatus for another RXCOMPLETE interrupt */
377 	hdq_reset_irqstatus(hdq_data);
378 
379 	/* read comp_bit */
380 	hdq_reg_merge(_hdq, OMAP_HDQ_CTRL_STATUS,
381 		      ctrl | OMAP_HDQ_CTRL_STATUS_DIR, mask);
382 	err = wait_event_timeout(hdq_wait_queue,
383 				 (hdq_data->hdq_irqstatus
384 				  & OMAP_HDQ_INT_STATUS_RXCOMPLETE),
385 				 OMAP_HDQ_TIMEOUT);
386 	if (err == 0) {
387 		dev_dbg(hdq_data->dev, "RX wait elapsed\n");
388 		goto out;
389 	}
390 	comp_bit = (hdq_reg_in(_hdq, OMAP_HDQ_RX_DATA) & 0x01);
391 
392 	if (id_bit && comp_bit) {
393 		ret = 0x03;  /* no slaves responded */
394 		goto out;
395 	}
396 	if (!id_bit && !comp_bit) {
397 		/* Both bits are valid, take the direction given */
398 		ret = bdir ? 0x04 : 0;
399 	} else {
400 		/* Only one bit is valid, take that direction */
401 		bdir = id_bit;
402 		ret = id_bit ? 0x05 : 0x02;
403 	}
404 
405 	/* write bdir bit */
406 	hdq_reg_out(_hdq, OMAP_HDQ_TX_DATA, bdir);
407 	hdq_reg_merge(_hdq, OMAP_HDQ_CTRL_STATUS, ctrl, mask);
408 	err = wait_event_timeout(hdq_wait_queue,
409 				 (hdq_data->hdq_irqstatus
410 				  & OMAP_HDQ_INT_STATUS_TXCOMPLETE),
411 				 OMAP_HDQ_TIMEOUT);
412 	if (err == 0) {
413 		dev_dbg(hdq_data->dev, "TX wait elapsed\n");
414 		goto out;
415 	}
416 
417 	hdq_reg_merge(_hdq, OMAP_HDQ_CTRL_STATUS, 0,
418 		      OMAP_HDQ_CTRL_STATUS_SINGLE);
419 
420 out:
421 	hdq_reset_irqstatus(hdq_data);
422 	mutex_unlock(&hdq_data->hdq_mutex);
423 rtn:
424 	pm_runtime_mark_last_busy(hdq_data->dev);
425 	pm_runtime_put_autosuspend(hdq_data->dev);
426 
427 	return ret;
428 }
429 
430 /* reset callback */
431 static u8 omap_w1_reset_bus(void *_hdq)
432 {
433 	struct hdq_data *hdq_data = _hdq;
434 	int err;
435 
436 	err = pm_runtime_get_sync(hdq_data->dev);
437 	if (err < 0) {
438 		pm_runtime_put_noidle(hdq_data->dev);
439 
440 		return err;
441 	}
442 
443 	omap_hdq_break(hdq_data);
444 
445 	pm_runtime_mark_last_busy(hdq_data->dev);
446 	pm_runtime_put_autosuspend(hdq_data->dev);
447 
448 	return 0;
449 }
450 
451 /* Read a byte of data from the device */
452 static u8 omap_w1_read_byte(void *_hdq)
453 {
454 	struct hdq_data *hdq_data = _hdq;
455 	u8 val = 0;
456 	int ret;
457 
458 	ret = pm_runtime_get_sync(hdq_data->dev);
459 	if (ret < 0) {
460 		pm_runtime_put_noidle(hdq_data->dev);
461 
462 		return -1;
463 	}
464 
465 	ret = hdq_read_byte(hdq_data, &val);
466 	if (ret)
467 		ret = -1;
468 
469 	pm_runtime_mark_last_busy(hdq_data->dev);
470 	pm_runtime_put_autosuspend(hdq_data->dev);
471 
472 	return val;
473 }
474 
475 /* Write a byte of data to the device */
476 static void omap_w1_write_byte(void *_hdq, u8 byte)
477 {
478 	struct hdq_data *hdq_data = _hdq;
479 	int ret;
480 	u8 status;
481 
482 	ret = pm_runtime_get_sync(hdq_data->dev);
483 	if (ret < 0) {
484 		pm_runtime_put_noidle(hdq_data->dev);
485 
486 		return;
487 	}
488 
489 	/*
490 	 * We need to reset the slave before
491 	 * issuing the SKIP ROM command, else
492 	 * the slave will not work.
493 	 */
494 	if (byte == W1_SKIP_ROM)
495 		omap_hdq_break(hdq_data);
496 
497 	ret = hdq_write_byte(hdq_data, byte, &status);
498 	if (ret < 0) {
499 		dev_dbg(hdq_data->dev, "TX failure:Ctrl status %x\n", status);
500 		goto out_err;
501 	}
502 
503 out_err:
504 	pm_runtime_mark_last_busy(hdq_data->dev);
505 	pm_runtime_put_autosuspend(hdq_data->dev);
506 }
507 
508 static struct w1_bus_master omap_w1_master = {
509 	.read_byte	= omap_w1_read_byte,
510 	.write_byte	= omap_w1_write_byte,
511 	.reset_bus	= omap_w1_reset_bus,
512 };
513 
514 static int __maybe_unused omap_hdq_runtime_suspend(struct device *dev)
515 {
516 	struct hdq_data *hdq_data = dev_get_drvdata(dev);
517 
518 	hdq_reg_out(hdq_data, 0, hdq_data->mode);
519 	hdq_reg_in(hdq_data, OMAP_HDQ_INT_STATUS);
520 
521 	return 0;
522 }
523 
524 static int __maybe_unused omap_hdq_runtime_resume(struct device *dev)
525 {
526 	struct hdq_data *hdq_data = dev_get_drvdata(dev);
527 
528 	/* select HDQ/1W mode & enable clocks */
529 	hdq_reg_out(hdq_data, OMAP_HDQ_CTRL_STATUS,
530 		    OMAP_HDQ_CTRL_STATUS_CLOCKENABLE |
531 		    OMAP_HDQ_CTRL_STATUS_INTERRUPTMASK |
532 		    hdq_data->mode);
533 	hdq_reg_in(hdq_data, OMAP_HDQ_INT_STATUS);
534 
535 	return 0;
536 }
537 
538 static const struct dev_pm_ops omap_hdq_pm_ops = {
539 	SET_RUNTIME_PM_OPS(omap_hdq_runtime_suspend,
540 			   omap_hdq_runtime_resume, NULL)
541 };
542 
543 static int omap_hdq_probe(struct platform_device *pdev)
544 {
545 	struct device *dev = &pdev->dev;
546 	struct hdq_data *hdq_data;
547 	int ret, irq;
548 	u8 rev;
549 	const char *mode;
550 
551 	hdq_data = devm_kzalloc(dev, sizeof(*hdq_data), GFP_KERNEL);
552 	if (!hdq_data) {
553 		dev_dbg(&pdev->dev, "unable to allocate memory\n");
554 		return -ENOMEM;
555 	}
556 
557 	hdq_data->dev = dev;
558 	platform_set_drvdata(pdev, hdq_data);
559 
560 	hdq_data->hdq_base = devm_platform_ioremap_resource(pdev, 0);
561 	if (IS_ERR(hdq_data->hdq_base))
562 		return PTR_ERR(hdq_data->hdq_base);
563 
564 	mutex_init(&hdq_data->hdq_mutex);
565 
566 	ret = of_property_read_string(pdev->dev.of_node, "ti,mode", &mode);
567 	if (ret < 0 || !strcmp(mode, "hdq")) {
568 		hdq_data->mode = 0;
569 		omap_w1_master.search = omap_w1_search_bus;
570 	} else {
571 		hdq_data->mode = 1;
572 		omap_w1_master.triplet = omap_w1_triplet;
573 	}
574 
575 	pm_runtime_enable(&pdev->dev);
576 	pm_runtime_use_autosuspend(&pdev->dev);
577 	pm_runtime_set_autosuspend_delay(&pdev->dev, 300);
578 	ret = pm_runtime_get_sync(&pdev->dev);
579 	if (ret < 0) {
580 		pm_runtime_put_noidle(&pdev->dev);
581 		dev_dbg(&pdev->dev, "pm_runtime_get_sync failed\n");
582 		goto err_w1;
583 	}
584 
585 	rev = hdq_reg_in(hdq_data, OMAP_HDQ_REVISION);
586 	dev_info(&pdev->dev, "OMAP HDQ Hardware Rev %c.%c. Driver in %s mode\n",
587 		(rev >> 4) + '0', (rev & 0x0f) + '0', "Interrupt");
588 
589 	spin_lock_init(&hdq_data->hdq_spinlock);
590 
591 	irq = platform_get_irq(pdev, 0);
592 	if (irq	< 0) {
593 		dev_dbg(&pdev->dev, "Failed to get IRQ: %d\n", irq);
594 		ret = irq;
595 		goto err_irq;
596 	}
597 
598 	ret = devm_request_irq(dev, irq, hdq_isr, 0, "omap_hdq", hdq_data);
599 	if (ret < 0) {
600 		dev_dbg(&pdev->dev, "could not request irq\n");
601 		goto err_irq;
602 	}
603 
604 	omap_hdq_break(hdq_data);
605 
606 	pm_runtime_mark_last_busy(&pdev->dev);
607 	pm_runtime_put_autosuspend(&pdev->dev);
608 
609 	omap_w1_master.data = hdq_data;
610 
611 	ret = w1_add_master_device(&omap_w1_master);
612 	if (ret) {
613 		dev_dbg(&pdev->dev, "Failure in registering w1 master\n");
614 		goto err_w1;
615 	}
616 
617 	return 0;
618 
619 err_irq:
620 	pm_runtime_put_sync(&pdev->dev);
621 err_w1:
622 	pm_runtime_dont_use_autosuspend(&pdev->dev);
623 	pm_runtime_disable(&pdev->dev);
624 
625 	return ret;
626 }
627 
628 static int omap_hdq_remove(struct platform_device *pdev)
629 {
630 	int active;
631 
632 	active = pm_runtime_get_sync(&pdev->dev);
633 	if (active < 0)
634 		pm_runtime_put_noidle(&pdev->dev);
635 
636 	w1_remove_master_device(&omap_w1_master);
637 
638 	pm_runtime_dont_use_autosuspend(&pdev->dev);
639 	if (active >= 0)
640 		pm_runtime_put_sync(&pdev->dev);
641 	pm_runtime_disable(&pdev->dev);
642 
643 	return 0;
644 }
645 
646 static const struct of_device_id omap_hdq_dt_ids[] = {
647 	{ .compatible = "ti,omap3-1w" },
648 	{ .compatible = "ti,am4372-hdq" },
649 	{}
650 };
651 MODULE_DEVICE_TABLE(of, omap_hdq_dt_ids);
652 
653 static struct platform_driver omap_hdq_driver = {
654 	.probe = omap_hdq_probe,
655 	.remove = omap_hdq_remove,
656 	.driver = {
657 		.name =	"omap_hdq",
658 		.of_match_table = omap_hdq_dt_ids,
659 		.pm = &omap_hdq_pm_ops,
660 	},
661 };
662 module_platform_driver(omap_hdq_driver);
663 
664 MODULE_AUTHOR("Texas Instruments");
665 MODULE_DESCRIPTION("HDQ-1W driver Library");
666 MODULE_LICENSE("GPL");
667