xref: /openbmc/linux/drivers/i3c/master.c (revision 2cf1c348)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (C) 2018 Cadence Design Systems Inc.
4  *
5  * Author: Boris Brezillon <boris.brezillon@bootlin.com>
6  */
7 
8 #include <linux/atomic.h>
9 #include <linux/bug.h>
10 #include <linux/device.h>
11 #include <linux/err.h>
12 #include <linux/export.h>
13 #include <linux/kernel.h>
14 #include <linux/list.h>
15 #include <linux/of.h>
16 #include <linux/slab.h>
17 #include <linux/spinlock.h>
18 #include <linux/workqueue.h>
19 
20 #include "internals.h"
21 
22 static DEFINE_IDR(i3c_bus_idr);
23 static DEFINE_MUTEX(i3c_core_lock);
24 
25 /**
26  * i3c_bus_maintenance_lock - Lock the bus for a maintenance operation
27  * @bus: I3C bus to take the lock on
28  *
29  * This function takes the bus lock so that no other operations can occur on
30  * the bus. This is needed for all kind of bus maintenance operation, like
31  * - enabling/disabling slave events
32  * - re-triggering DAA
33  * - changing the dynamic address of a device
34  * - relinquishing mastership
35  * - ...
36  *
37  * The reason for this kind of locking is that we don't want drivers and core
38  * logic to rely on I3C device information that could be changed behind their
39  * back.
40  */
41 static void i3c_bus_maintenance_lock(struct i3c_bus *bus)
42 {
43 	down_write(&bus->lock);
44 }
45 
46 /**
47  * i3c_bus_maintenance_unlock - Release the bus lock after a maintenance
48  *			      operation
49  * @bus: I3C bus to release the lock on
50  *
51  * Should be called when the bus maintenance operation is done. See
52  * i3c_bus_maintenance_lock() for more details on what these maintenance
53  * operations are.
54  */
55 static void i3c_bus_maintenance_unlock(struct i3c_bus *bus)
56 {
57 	up_write(&bus->lock);
58 }
59 
60 /**
61  * i3c_bus_normaluse_lock - Lock the bus for a normal operation
62  * @bus: I3C bus to take the lock on
63  *
64  * This function takes the bus lock for any operation that is not a maintenance
65  * operation (see i3c_bus_maintenance_lock() for a non-exhaustive list of
66  * maintenance operations). Basically all communications with I3C devices are
67  * normal operations (HDR, SDR transfers or CCC commands that do not change bus
68  * state or I3C dynamic address).
69  *
70  * Note that this lock is not guaranteeing serialization of normal operations.
71  * In other words, transfer requests passed to the I3C master can be submitted
72  * in parallel and I3C master drivers have to use their own locking to make
73  * sure two different communications are not inter-mixed, or access to the
74  * output/input queue is not done while the engine is busy.
75  */
76 void i3c_bus_normaluse_lock(struct i3c_bus *bus)
77 {
78 	down_read(&bus->lock);
79 }
80 
81 /**
82  * i3c_bus_normaluse_unlock - Release the bus lock after a normal operation
83  * @bus: I3C bus to release the lock on
84  *
85  * Should be called when a normal operation is done. See
86  * i3c_bus_normaluse_lock() for more details on what these normal operations
87  * are.
88  */
89 void i3c_bus_normaluse_unlock(struct i3c_bus *bus)
90 {
91 	up_read(&bus->lock);
92 }
93 
94 static struct i3c_master_controller *
95 i3c_bus_to_i3c_master(struct i3c_bus *i3cbus)
96 {
97 	return container_of(i3cbus, struct i3c_master_controller, bus);
98 }
99 
100 static struct i3c_master_controller *dev_to_i3cmaster(struct device *dev)
101 {
102 	return container_of(dev, struct i3c_master_controller, dev);
103 }
104 
105 static const struct device_type i3c_device_type;
106 
107 static struct i3c_bus *dev_to_i3cbus(struct device *dev)
108 {
109 	struct i3c_master_controller *master;
110 
111 	if (dev->type == &i3c_device_type)
112 		return dev_to_i3cdev(dev)->bus;
113 
114 	master = dev_to_i3cmaster(dev);
115 
116 	return &master->bus;
117 }
118 
119 static struct i3c_dev_desc *dev_to_i3cdesc(struct device *dev)
120 {
121 	struct i3c_master_controller *master;
122 
123 	if (dev->type == &i3c_device_type)
124 		return dev_to_i3cdev(dev)->desc;
125 
126 	master = dev_to_i3cmaster(dev);
127 
128 	return master->this;
129 }
130 
131 static ssize_t bcr_show(struct device *dev,
132 			struct device_attribute *da,
133 			char *buf)
134 {
135 	struct i3c_bus *bus = dev_to_i3cbus(dev);
136 	struct i3c_dev_desc *desc;
137 	ssize_t ret;
138 
139 	i3c_bus_normaluse_lock(bus);
140 	desc = dev_to_i3cdesc(dev);
141 	ret = sprintf(buf, "%x\n", desc->info.bcr);
142 	i3c_bus_normaluse_unlock(bus);
143 
144 	return ret;
145 }
146 static DEVICE_ATTR_RO(bcr);
147 
148 static ssize_t dcr_show(struct device *dev,
149 			struct device_attribute *da,
150 			char *buf)
151 {
152 	struct i3c_bus *bus = dev_to_i3cbus(dev);
153 	struct i3c_dev_desc *desc;
154 	ssize_t ret;
155 
156 	i3c_bus_normaluse_lock(bus);
157 	desc = dev_to_i3cdesc(dev);
158 	ret = sprintf(buf, "%x\n", desc->info.dcr);
159 	i3c_bus_normaluse_unlock(bus);
160 
161 	return ret;
162 }
163 static DEVICE_ATTR_RO(dcr);
164 
165 static ssize_t pid_show(struct device *dev,
166 			struct device_attribute *da,
167 			char *buf)
168 {
169 	struct i3c_bus *bus = dev_to_i3cbus(dev);
170 	struct i3c_dev_desc *desc;
171 	ssize_t ret;
172 
173 	i3c_bus_normaluse_lock(bus);
174 	desc = dev_to_i3cdesc(dev);
175 	ret = sprintf(buf, "%llx\n", desc->info.pid);
176 	i3c_bus_normaluse_unlock(bus);
177 
178 	return ret;
179 }
180 static DEVICE_ATTR_RO(pid);
181 
182 static ssize_t dynamic_address_show(struct device *dev,
183 				    struct device_attribute *da,
184 				    char *buf)
185 {
186 	struct i3c_bus *bus = dev_to_i3cbus(dev);
187 	struct i3c_dev_desc *desc;
188 	ssize_t ret;
189 
190 	i3c_bus_normaluse_lock(bus);
191 	desc = dev_to_i3cdesc(dev);
192 	ret = sprintf(buf, "%02x\n", desc->info.dyn_addr);
193 	i3c_bus_normaluse_unlock(bus);
194 
195 	return ret;
196 }
197 static DEVICE_ATTR_RO(dynamic_address);
198 
199 static const char * const hdrcap_strings[] = {
200 	"hdr-ddr", "hdr-tsp", "hdr-tsl",
201 };
202 
203 static ssize_t hdrcap_show(struct device *dev,
204 			   struct device_attribute *da,
205 			   char *buf)
206 {
207 	struct i3c_bus *bus = dev_to_i3cbus(dev);
208 	struct i3c_dev_desc *desc;
209 	ssize_t offset = 0, ret;
210 	unsigned long caps;
211 	int mode;
212 
213 	i3c_bus_normaluse_lock(bus);
214 	desc = dev_to_i3cdesc(dev);
215 	caps = desc->info.hdr_cap;
216 	for_each_set_bit(mode, &caps, 8) {
217 		if (mode >= ARRAY_SIZE(hdrcap_strings))
218 			break;
219 
220 		if (!hdrcap_strings[mode])
221 			continue;
222 
223 		ret = sprintf(buf + offset, offset ? " %s" : "%s",
224 			      hdrcap_strings[mode]);
225 		if (ret < 0)
226 			goto out;
227 
228 		offset += ret;
229 	}
230 
231 	ret = sprintf(buf + offset, "\n");
232 	if (ret < 0)
233 		goto out;
234 
235 	ret = offset + ret;
236 
237 out:
238 	i3c_bus_normaluse_unlock(bus);
239 
240 	return ret;
241 }
242 static DEVICE_ATTR_RO(hdrcap);
243 
244 static ssize_t modalias_show(struct device *dev,
245 			     struct device_attribute *da, char *buf)
246 {
247 	struct i3c_device *i3c = dev_to_i3cdev(dev);
248 	struct i3c_device_info devinfo;
249 	u16 manuf, part, ext;
250 
251 	i3c_device_get_info(i3c, &devinfo);
252 	manuf = I3C_PID_MANUF_ID(devinfo.pid);
253 	part = I3C_PID_PART_ID(devinfo.pid);
254 	ext = I3C_PID_EXTRA_INFO(devinfo.pid);
255 
256 	if (I3C_PID_RND_LOWER_32BITS(devinfo.pid))
257 		return sprintf(buf, "i3c:dcr%02Xmanuf%04X", devinfo.dcr,
258 			       manuf);
259 
260 	return sprintf(buf, "i3c:dcr%02Xmanuf%04Xpart%04Xext%04X",
261 		       devinfo.dcr, manuf, part, ext);
262 }
263 static DEVICE_ATTR_RO(modalias);
264 
265 static struct attribute *i3c_device_attrs[] = {
266 	&dev_attr_bcr.attr,
267 	&dev_attr_dcr.attr,
268 	&dev_attr_pid.attr,
269 	&dev_attr_dynamic_address.attr,
270 	&dev_attr_hdrcap.attr,
271 	&dev_attr_modalias.attr,
272 	NULL,
273 };
274 ATTRIBUTE_GROUPS(i3c_device);
275 
276 static int i3c_device_uevent(struct device *dev, struct kobj_uevent_env *env)
277 {
278 	struct i3c_device *i3cdev = dev_to_i3cdev(dev);
279 	struct i3c_device_info devinfo;
280 	u16 manuf, part, ext;
281 
282 	i3c_device_get_info(i3cdev, &devinfo);
283 	manuf = I3C_PID_MANUF_ID(devinfo.pid);
284 	part = I3C_PID_PART_ID(devinfo.pid);
285 	ext = I3C_PID_EXTRA_INFO(devinfo.pid);
286 
287 	if (I3C_PID_RND_LOWER_32BITS(devinfo.pid))
288 		return add_uevent_var(env, "MODALIAS=i3c:dcr%02Xmanuf%04X",
289 				      devinfo.dcr, manuf);
290 
291 	return add_uevent_var(env,
292 			      "MODALIAS=i3c:dcr%02Xmanuf%04Xpart%04Xext%04X",
293 			      devinfo.dcr, manuf, part, ext);
294 }
295 
296 static const struct device_type i3c_device_type = {
297 	.groups	= i3c_device_groups,
298 	.uevent = i3c_device_uevent,
299 };
300 
301 static int i3c_device_match(struct device *dev, struct device_driver *drv)
302 {
303 	struct i3c_device *i3cdev;
304 	struct i3c_driver *i3cdrv;
305 
306 	if (dev->type != &i3c_device_type)
307 		return 0;
308 
309 	i3cdev = dev_to_i3cdev(dev);
310 	i3cdrv = drv_to_i3cdrv(drv);
311 	if (i3c_device_match_id(i3cdev, i3cdrv->id_table))
312 		return 1;
313 
314 	return 0;
315 }
316 
317 static int i3c_device_probe(struct device *dev)
318 {
319 	struct i3c_device *i3cdev = dev_to_i3cdev(dev);
320 	struct i3c_driver *driver = drv_to_i3cdrv(dev->driver);
321 
322 	return driver->probe(i3cdev);
323 }
324 
325 static void i3c_device_remove(struct device *dev)
326 {
327 	struct i3c_device *i3cdev = dev_to_i3cdev(dev);
328 	struct i3c_driver *driver = drv_to_i3cdrv(dev->driver);
329 
330 	if (driver->remove)
331 		driver->remove(i3cdev);
332 
333 	i3c_device_free_ibi(i3cdev);
334 }
335 
336 struct bus_type i3c_bus_type = {
337 	.name = "i3c",
338 	.match = i3c_device_match,
339 	.probe = i3c_device_probe,
340 	.remove = i3c_device_remove,
341 };
342 
343 static enum i3c_addr_slot_status
344 i3c_bus_get_addr_slot_status(struct i3c_bus *bus, u16 addr)
345 {
346 	unsigned long status;
347 	int bitpos = addr * 2;
348 
349 	if (addr > I2C_MAX_ADDR)
350 		return I3C_ADDR_SLOT_RSVD;
351 
352 	status = bus->addrslots[bitpos / BITS_PER_LONG];
353 	status >>= bitpos % BITS_PER_LONG;
354 
355 	return status & I3C_ADDR_SLOT_STATUS_MASK;
356 }
357 
358 static void i3c_bus_set_addr_slot_status(struct i3c_bus *bus, u16 addr,
359 					 enum i3c_addr_slot_status status)
360 {
361 	int bitpos = addr * 2;
362 	unsigned long *ptr;
363 
364 	if (addr > I2C_MAX_ADDR)
365 		return;
366 
367 	ptr = bus->addrslots + (bitpos / BITS_PER_LONG);
368 	*ptr &= ~((unsigned long)I3C_ADDR_SLOT_STATUS_MASK <<
369 						(bitpos % BITS_PER_LONG));
370 	*ptr |= (unsigned long)status << (bitpos % BITS_PER_LONG);
371 }
372 
373 static bool i3c_bus_dev_addr_is_avail(struct i3c_bus *bus, u8 addr)
374 {
375 	enum i3c_addr_slot_status status;
376 
377 	status = i3c_bus_get_addr_slot_status(bus, addr);
378 
379 	return status == I3C_ADDR_SLOT_FREE;
380 }
381 
382 static int i3c_bus_get_free_addr(struct i3c_bus *bus, u8 start_addr)
383 {
384 	enum i3c_addr_slot_status status;
385 	u8 addr;
386 
387 	for (addr = start_addr; addr < I3C_MAX_ADDR; addr++) {
388 		status = i3c_bus_get_addr_slot_status(bus, addr);
389 		if (status == I3C_ADDR_SLOT_FREE)
390 			return addr;
391 	}
392 
393 	return -ENOMEM;
394 }
395 
396 static void i3c_bus_init_addrslots(struct i3c_bus *bus)
397 {
398 	int i;
399 
400 	/* Addresses 0 to 7 are reserved. */
401 	for (i = 0; i < 8; i++)
402 		i3c_bus_set_addr_slot_status(bus, i, I3C_ADDR_SLOT_RSVD);
403 
404 	/*
405 	 * Reserve broadcast address and all addresses that might collide
406 	 * with the broadcast address when facing a single bit error.
407 	 */
408 	i3c_bus_set_addr_slot_status(bus, I3C_BROADCAST_ADDR,
409 				     I3C_ADDR_SLOT_RSVD);
410 	for (i = 0; i < 7; i++)
411 		i3c_bus_set_addr_slot_status(bus, I3C_BROADCAST_ADDR ^ BIT(i),
412 					     I3C_ADDR_SLOT_RSVD);
413 }
414 
415 static void i3c_bus_cleanup(struct i3c_bus *i3cbus)
416 {
417 	mutex_lock(&i3c_core_lock);
418 	idr_remove(&i3c_bus_idr, i3cbus->id);
419 	mutex_unlock(&i3c_core_lock);
420 }
421 
422 static int i3c_bus_init(struct i3c_bus *i3cbus)
423 {
424 	int ret;
425 
426 	init_rwsem(&i3cbus->lock);
427 	INIT_LIST_HEAD(&i3cbus->devs.i2c);
428 	INIT_LIST_HEAD(&i3cbus->devs.i3c);
429 	i3c_bus_init_addrslots(i3cbus);
430 	i3cbus->mode = I3C_BUS_MODE_PURE;
431 
432 	mutex_lock(&i3c_core_lock);
433 	ret = idr_alloc(&i3c_bus_idr, i3cbus, 0, 0, GFP_KERNEL);
434 	mutex_unlock(&i3c_core_lock);
435 
436 	if (ret < 0)
437 		return ret;
438 
439 	i3cbus->id = ret;
440 
441 	return 0;
442 }
443 
444 static const char * const i3c_bus_mode_strings[] = {
445 	[I3C_BUS_MODE_PURE] = "pure",
446 	[I3C_BUS_MODE_MIXED_FAST] = "mixed-fast",
447 	[I3C_BUS_MODE_MIXED_LIMITED] = "mixed-limited",
448 	[I3C_BUS_MODE_MIXED_SLOW] = "mixed-slow",
449 };
450 
451 static ssize_t mode_show(struct device *dev,
452 			 struct device_attribute *da,
453 			 char *buf)
454 {
455 	struct i3c_bus *i3cbus = dev_to_i3cbus(dev);
456 	ssize_t ret;
457 
458 	i3c_bus_normaluse_lock(i3cbus);
459 	if (i3cbus->mode < 0 ||
460 	    i3cbus->mode >= ARRAY_SIZE(i3c_bus_mode_strings) ||
461 	    !i3c_bus_mode_strings[i3cbus->mode])
462 		ret = sprintf(buf, "unknown\n");
463 	else
464 		ret = sprintf(buf, "%s\n", i3c_bus_mode_strings[i3cbus->mode]);
465 	i3c_bus_normaluse_unlock(i3cbus);
466 
467 	return ret;
468 }
469 static DEVICE_ATTR_RO(mode);
470 
471 static ssize_t current_master_show(struct device *dev,
472 				   struct device_attribute *da,
473 				   char *buf)
474 {
475 	struct i3c_bus *i3cbus = dev_to_i3cbus(dev);
476 	ssize_t ret;
477 
478 	i3c_bus_normaluse_lock(i3cbus);
479 	ret = sprintf(buf, "%d-%llx\n", i3cbus->id,
480 		      i3cbus->cur_master->info.pid);
481 	i3c_bus_normaluse_unlock(i3cbus);
482 
483 	return ret;
484 }
485 static DEVICE_ATTR_RO(current_master);
486 
487 static ssize_t i3c_scl_frequency_show(struct device *dev,
488 				      struct device_attribute *da,
489 				      char *buf)
490 {
491 	struct i3c_bus *i3cbus = dev_to_i3cbus(dev);
492 	ssize_t ret;
493 
494 	i3c_bus_normaluse_lock(i3cbus);
495 	ret = sprintf(buf, "%ld\n", i3cbus->scl_rate.i3c);
496 	i3c_bus_normaluse_unlock(i3cbus);
497 
498 	return ret;
499 }
500 static DEVICE_ATTR_RO(i3c_scl_frequency);
501 
502 static ssize_t i2c_scl_frequency_show(struct device *dev,
503 				      struct device_attribute *da,
504 				      char *buf)
505 {
506 	struct i3c_bus *i3cbus = dev_to_i3cbus(dev);
507 	ssize_t ret;
508 
509 	i3c_bus_normaluse_lock(i3cbus);
510 	ret = sprintf(buf, "%ld\n", i3cbus->scl_rate.i2c);
511 	i3c_bus_normaluse_unlock(i3cbus);
512 
513 	return ret;
514 }
515 static DEVICE_ATTR_RO(i2c_scl_frequency);
516 
517 static struct attribute *i3c_masterdev_attrs[] = {
518 	&dev_attr_mode.attr,
519 	&dev_attr_current_master.attr,
520 	&dev_attr_i3c_scl_frequency.attr,
521 	&dev_attr_i2c_scl_frequency.attr,
522 	&dev_attr_bcr.attr,
523 	&dev_attr_dcr.attr,
524 	&dev_attr_pid.attr,
525 	&dev_attr_dynamic_address.attr,
526 	&dev_attr_hdrcap.attr,
527 	NULL,
528 };
529 ATTRIBUTE_GROUPS(i3c_masterdev);
530 
531 static void i3c_masterdev_release(struct device *dev)
532 {
533 	struct i3c_master_controller *master = dev_to_i3cmaster(dev);
534 	struct i3c_bus *bus = dev_to_i3cbus(dev);
535 
536 	if (master->wq)
537 		destroy_workqueue(master->wq);
538 
539 	WARN_ON(!list_empty(&bus->devs.i2c) || !list_empty(&bus->devs.i3c));
540 	i3c_bus_cleanup(bus);
541 
542 	of_node_put(dev->of_node);
543 }
544 
545 static const struct device_type i3c_masterdev_type = {
546 	.groups	= i3c_masterdev_groups,
547 };
548 
549 static int i3c_bus_set_mode(struct i3c_bus *i3cbus, enum i3c_bus_mode mode,
550 			    unsigned long max_i2c_scl_rate)
551 {
552 	struct i3c_master_controller *master = i3c_bus_to_i3c_master(i3cbus);
553 
554 	i3cbus->mode = mode;
555 
556 	switch (i3cbus->mode) {
557 	case I3C_BUS_MODE_PURE:
558 		if (!i3cbus->scl_rate.i3c)
559 			i3cbus->scl_rate.i3c = I3C_BUS_TYP_I3C_SCL_RATE;
560 		break;
561 	case I3C_BUS_MODE_MIXED_FAST:
562 	case I3C_BUS_MODE_MIXED_LIMITED:
563 		if (!i3cbus->scl_rate.i3c)
564 			i3cbus->scl_rate.i3c = I3C_BUS_TYP_I3C_SCL_RATE;
565 		if (!i3cbus->scl_rate.i2c)
566 			i3cbus->scl_rate.i2c = max_i2c_scl_rate;
567 		break;
568 	case I3C_BUS_MODE_MIXED_SLOW:
569 		if (!i3cbus->scl_rate.i2c)
570 			i3cbus->scl_rate.i2c = max_i2c_scl_rate;
571 		if (!i3cbus->scl_rate.i3c ||
572 		    i3cbus->scl_rate.i3c > i3cbus->scl_rate.i2c)
573 			i3cbus->scl_rate.i3c = i3cbus->scl_rate.i2c;
574 		break;
575 	default:
576 		return -EINVAL;
577 	}
578 
579 	dev_dbg(&master->dev, "i2c-scl = %ld Hz i3c-scl = %ld Hz\n",
580 		i3cbus->scl_rate.i2c, i3cbus->scl_rate.i3c);
581 
582 	/*
583 	 * I3C/I2C frequency may have been overridden, check that user-provided
584 	 * values are not exceeding max possible frequency.
585 	 */
586 	if (i3cbus->scl_rate.i3c > I3C_BUS_MAX_I3C_SCL_RATE ||
587 	    i3cbus->scl_rate.i2c > I3C_BUS_I2C_FM_PLUS_SCL_RATE)
588 		return -EINVAL;
589 
590 	return 0;
591 }
592 
593 static struct i3c_master_controller *
594 i2c_adapter_to_i3c_master(struct i2c_adapter *adap)
595 {
596 	return container_of(adap, struct i3c_master_controller, i2c);
597 }
598 
599 static struct i2c_adapter *
600 i3c_master_to_i2c_adapter(struct i3c_master_controller *master)
601 {
602 	return &master->i2c;
603 }
604 
605 static void i3c_master_free_i2c_dev(struct i2c_dev_desc *dev)
606 {
607 	kfree(dev);
608 }
609 
610 static struct i2c_dev_desc *
611 i3c_master_alloc_i2c_dev(struct i3c_master_controller *master,
612 			 const struct i2c_dev_boardinfo *boardinfo)
613 {
614 	struct i2c_dev_desc *dev;
615 
616 	dev = kzalloc(sizeof(*dev), GFP_KERNEL);
617 	if (!dev)
618 		return ERR_PTR(-ENOMEM);
619 
620 	dev->common.master = master;
621 	dev->boardinfo = boardinfo;
622 	dev->addr = boardinfo->base.addr;
623 	dev->lvr = boardinfo->lvr;
624 
625 	return dev;
626 }
627 
628 static void *i3c_ccc_cmd_dest_init(struct i3c_ccc_cmd_dest *dest, u8 addr,
629 				   u16 payloadlen)
630 {
631 	dest->addr = addr;
632 	dest->payload.len = payloadlen;
633 	if (payloadlen)
634 		dest->payload.data = kzalloc(payloadlen, GFP_KERNEL);
635 	else
636 		dest->payload.data = NULL;
637 
638 	return dest->payload.data;
639 }
640 
641 static void i3c_ccc_cmd_dest_cleanup(struct i3c_ccc_cmd_dest *dest)
642 {
643 	kfree(dest->payload.data);
644 }
645 
646 static void i3c_ccc_cmd_init(struct i3c_ccc_cmd *cmd, bool rnw, u8 id,
647 			     struct i3c_ccc_cmd_dest *dests,
648 			     unsigned int ndests)
649 {
650 	cmd->rnw = rnw ? 1 : 0;
651 	cmd->id = id;
652 	cmd->dests = dests;
653 	cmd->ndests = ndests;
654 	cmd->err = I3C_ERROR_UNKNOWN;
655 }
656 
657 static int i3c_master_send_ccc_cmd_locked(struct i3c_master_controller *master,
658 					  struct i3c_ccc_cmd *cmd)
659 {
660 	int ret;
661 
662 	if (!cmd || !master)
663 		return -EINVAL;
664 
665 	if (WARN_ON(master->init_done &&
666 		    !rwsem_is_locked(&master->bus.lock)))
667 		return -EINVAL;
668 
669 	if (!master->ops->send_ccc_cmd)
670 		return -ENOTSUPP;
671 
672 	if ((cmd->id & I3C_CCC_DIRECT) && (!cmd->dests || !cmd->ndests))
673 		return -EINVAL;
674 
675 	if (master->ops->supports_ccc_cmd &&
676 	    !master->ops->supports_ccc_cmd(master, cmd))
677 		return -ENOTSUPP;
678 
679 	ret = master->ops->send_ccc_cmd(master, cmd);
680 	if (ret) {
681 		if (cmd->err != I3C_ERROR_UNKNOWN)
682 			return cmd->err;
683 
684 		return ret;
685 	}
686 
687 	return 0;
688 }
689 
690 static struct i2c_dev_desc *
691 i3c_master_find_i2c_dev_by_addr(const struct i3c_master_controller *master,
692 				u16 addr)
693 {
694 	struct i2c_dev_desc *dev;
695 
696 	i3c_bus_for_each_i2cdev(&master->bus, dev) {
697 		if (dev->boardinfo->base.addr == addr)
698 			return dev;
699 	}
700 
701 	return NULL;
702 }
703 
704 /**
705  * i3c_master_get_free_addr() - get a free address on the bus
706  * @master: I3C master object
707  * @start_addr: where to start searching
708  *
709  * This function must be called with the bus lock held in write mode.
710  *
711  * Return: the first free address starting at @start_addr (included) or -ENOMEM
712  * if there's no more address available.
713  */
714 int i3c_master_get_free_addr(struct i3c_master_controller *master,
715 			     u8 start_addr)
716 {
717 	return i3c_bus_get_free_addr(&master->bus, start_addr);
718 }
719 EXPORT_SYMBOL_GPL(i3c_master_get_free_addr);
720 
721 static void i3c_device_release(struct device *dev)
722 {
723 	struct i3c_device *i3cdev = dev_to_i3cdev(dev);
724 
725 	WARN_ON(i3cdev->desc);
726 
727 	of_node_put(i3cdev->dev.of_node);
728 	kfree(i3cdev);
729 }
730 
731 static void i3c_master_free_i3c_dev(struct i3c_dev_desc *dev)
732 {
733 	kfree(dev);
734 }
735 
736 static struct i3c_dev_desc *
737 i3c_master_alloc_i3c_dev(struct i3c_master_controller *master,
738 			 const struct i3c_device_info *info)
739 {
740 	struct i3c_dev_desc *dev;
741 
742 	dev = kzalloc(sizeof(*dev), GFP_KERNEL);
743 	if (!dev)
744 		return ERR_PTR(-ENOMEM);
745 
746 	dev->common.master = master;
747 	dev->info = *info;
748 	mutex_init(&dev->ibi_lock);
749 
750 	return dev;
751 }
752 
753 static int i3c_master_rstdaa_locked(struct i3c_master_controller *master,
754 				    u8 addr)
755 {
756 	enum i3c_addr_slot_status addrstat;
757 	struct i3c_ccc_cmd_dest dest;
758 	struct i3c_ccc_cmd cmd;
759 	int ret;
760 
761 	if (!master)
762 		return -EINVAL;
763 
764 	addrstat = i3c_bus_get_addr_slot_status(&master->bus, addr);
765 	if (addr != I3C_BROADCAST_ADDR && addrstat != I3C_ADDR_SLOT_I3C_DEV)
766 		return -EINVAL;
767 
768 	i3c_ccc_cmd_dest_init(&dest, addr, 0);
769 	i3c_ccc_cmd_init(&cmd, false,
770 			 I3C_CCC_RSTDAA(addr == I3C_BROADCAST_ADDR),
771 			 &dest, 1);
772 	ret = i3c_master_send_ccc_cmd_locked(master, &cmd);
773 	i3c_ccc_cmd_dest_cleanup(&dest);
774 
775 	return ret;
776 }
777 
778 /**
779  * i3c_master_entdaa_locked() - start a DAA (Dynamic Address Assignment)
780  *				procedure
781  * @master: master used to send frames on the bus
782  *
783  * Send a ENTDAA CCC command to start a DAA procedure.
784  *
785  * Note that this function only sends the ENTDAA CCC command, all the logic
786  * behind dynamic address assignment has to be handled in the I3C master
787  * driver.
788  *
789  * This function must be called with the bus lock held in write mode.
790  *
791  * Return: 0 in case of success, a positive I3C error code if the error is
792  * one of the official Mx error codes, and a negative error code otherwise.
793  */
794 int i3c_master_entdaa_locked(struct i3c_master_controller *master)
795 {
796 	struct i3c_ccc_cmd_dest dest;
797 	struct i3c_ccc_cmd cmd;
798 	int ret;
799 
800 	i3c_ccc_cmd_dest_init(&dest, I3C_BROADCAST_ADDR, 0);
801 	i3c_ccc_cmd_init(&cmd, false, I3C_CCC_ENTDAA, &dest, 1);
802 	ret = i3c_master_send_ccc_cmd_locked(master, &cmd);
803 	i3c_ccc_cmd_dest_cleanup(&dest);
804 
805 	return ret;
806 }
807 EXPORT_SYMBOL_GPL(i3c_master_entdaa_locked);
808 
809 static int i3c_master_enec_disec_locked(struct i3c_master_controller *master,
810 					u8 addr, bool enable, u8 evts)
811 {
812 	struct i3c_ccc_events *events;
813 	struct i3c_ccc_cmd_dest dest;
814 	struct i3c_ccc_cmd cmd;
815 	int ret;
816 
817 	events = i3c_ccc_cmd_dest_init(&dest, addr, sizeof(*events));
818 	if (!events)
819 		return -ENOMEM;
820 
821 	events->events = evts;
822 	i3c_ccc_cmd_init(&cmd, false,
823 			 enable ?
824 			 I3C_CCC_ENEC(addr == I3C_BROADCAST_ADDR) :
825 			 I3C_CCC_DISEC(addr == I3C_BROADCAST_ADDR),
826 			 &dest, 1);
827 	ret = i3c_master_send_ccc_cmd_locked(master, &cmd);
828 	i3c_ccc_cmd_dest_cleanup(&dest);
829 
830 	return ret;
831 }
832 
833 /**
834  * i3c_master_disec_locked() - send a DISEC CCC command
835  * @master: master used to send frames on the bus
836  * @addr: a valid I3C slave address or %I3C_BROADCAST_ADDR
837  * @evts: events to disable
838  *
839  * Send a DISEC CCC command to disable some or all events coming from a
840  * specific slave, or all devices if @addr is %I3C_BROADCAST_ADDR.
841  *
842  * This function must be called with the bus lock held in write mode.
843  *
844  * Return: 0 in case of success, a positive I3C error code if the error is
845  * one of the official Mx error codes, and a negative error code otherwise.
846  */
847 int i3c_master_disec_locked(struct i3c_master_controller *master, u8 addr,
848 			    u8 evts)
849 {
850 	return i3c_master_enec_disec_locked(master, addr, false, evts);
851 }
852 EXPORT_SYMBOL_GPL(i3c_master_disec_locked);
853 
854 /**
855  * i3c_master_enec_locked() - send an ENEC CCC command
856  * @master: master used to send frames on the bus
857  * @addr: a valid I3C slave address or %I3C_BROADCAST_ADDR
858  * @evts: events to disable
859  *
860  * Sends an ENEC CCC command to enable some or all events coming from a
861  * specific slave, or all devices if @addr is %I3C_BROADCAST_ADDR.
862  *
863  * This function must be called with the bus lock held in write mode.
864  *
865  * Return: 0 in case of success, a positive I3C error code if the error is
866  * one of the official Mx error codes, and a negative error code otherwise.
867  */
868 int i3c_master_enec_locked(struct i3c_master_controller *master, u8 addr,
869 			   u8 evts)
870 {
871 	return i3c_master_enec_disec_locked(master, addr, true, evts);
872 }
873 EXPORT_SYMBOL_GPL(i3c_master_enec_locked);
874 
875 /**
876  * i3c_master_defslvs_locked() - send a DEFSLVS CCC command
877  * @master: master used to send frames on the bus
878  *
879  * Send a DEFSLVS CCC command containing all the devices known to the @master.
880  * This is useful when you have secondary masters on the bus to propagate
881  * device information.
882  *
883  * This should be called after all I3C devices have been discovered (in other
884  * words, after the DAA procedure has finished) and instantiated in
885  * &i3c_master_controller_ops->bus_init().
886  * It should also be called if a master ACKed an Hot-Join request and assigned
887  * a dynamic address to the device joining the bus.
888  *
889  * This function must be called with the bus lock held in write mode.
890  *
891  * Return: 0 in case of success, a positive I3C error code if the error is
892  * one of the official Mx error codes, and a negative error code otherwise.
893  */
894 int i3c_master_defslvs_locked(struct i3c_master_controller *master)
895 {
896 	struct i3c_ccc_defslvs *defslvs;
897 	struct i3c_ccc_dev_desc *desc;
898 	struct i3c_ccc_cmd_dest dest;
899 	struct i3c_dev_desc *i3cdev;
900 	struct i2c_dev_desc *i2cdev;
901 	struct i3c_ccc_cmd cmd;
902 	struct i3c_bus *bus;
903 	bool send = false;
904 	int ndevs = 0, ret;
905 
906 	if (!master)
907 		return -EINVAL;
908 
909 	bus = i3c_master_get_bus(master);
910 	i3c_bus_for_each_i3cdev(bus, i3cdev) {
911 		ndevs++;
912 
913 		if (i3cdev == master->this)
914 			continue;
915 
916 		if (I3C_BCR_DEVICE_ROLE(i3cdev->info.bcr) ==
917 		    I3C_BCR_I3C_MASTER)
918 			send = true;
919 	}
920 
921 	/* No other master on the bus, skip DEFSLVS. */
922 	if (!send)
923 		return 0;
924 
925 	i3c_bus_for_each_i2cdev(bus, i2cdev)
926 		ndevs++;
927 
928 	defslvs = i3c_ccc_cmd_dest_init(&dest, I3C_BROADCAST_ADDR,
929 					struct_size(defslvs, slaves,
930 						    ndevs - 1));
931 	if (!defslvs)
932 		return -ENOMEM;
933 
934 	defslvs->count = ndevs;
935 	defslvs->master.bcr = master->this->info.bcr;
936 	defslvs->master.dcr = master->this->info.dcr;
937 	defslvs->master.dyn_addr = master->this->info.dyn_addr << 1;
938 	defslvs->master.static_addr = I3C_BROADCAST_ADDR << 1;
939 
940 	desc = defslvs->slaves;
941 	i3c_bus_for_each_i2cdev(bus, i2cdev) {
942 		desc->lvr = i2cdev->lvr;
943 		desc->static_addr = i2cdev->addr << 1;
944 		desc++;
945 	}
946 
947 	i3c_bus_for_each_i3cdev(bus, i3cdev) {
948 		/* Skip the I3C dev representing this master. */
949 		if (i3cdev == master->this)
950 			continue;
951 
952 		desc->bcr = i3cdev->info.bcr;
953 		desc->dcr = i3cdev->info.dcr;
954 		desc->dyn_addr = i3cdev->info.dyn_addr << 1;
955 		desc->static_addr = i3cdev->info.static_addr << 1;
956 		desc++;
957 	}
958 
959 	i3c_ccc_cmd_init(&cmd, false, I3C_CCC_DEFSLVS, &dest, 1);
960 	ret = i3c_master_send_ccc_cmd_locked(master, &cmd);
961 	i3c_ccc_cmd_dest_cleanup(&dest);
962 
963 	return ret;
964 }
965 EXPORT_SYMBOL_GPL(i3c_master_defslvs_locked);
966 
967 static int i3c_master_setda_locked(struct i3c_master_controller *master,
968 				   u8 oldaddr, u8 newaddr, bool setdasa)
969 {
970 	struct i3c_ccc_cmd_dest dest;
971 	struct i3c_ccc_setda *setda;
972 	struct i3c_ccc_cmd cmd;
973 	int ret;
974 
975 	if (!oldaddr || !newaddr)
976 		return -EINVAL;
977 
978 	setda = i3c_ccc_cmd_dest_init(&dest, oldaddr, sizeof(*setda));
979 	if (!setda)
980 		return -ENOMEM;
981 
982 	setda->addr = newaddr << 1;
983 	i3c_ccc_cmd_init(&cmd, false,
984 			 setdasa ? I3C_CCC_SETDASA : I3C_CCC_SETNEWDA,
985 			 &dest, 1);
986 	ret = i3c_master_send_ccc_cmd_locked(master, &cmd);
987 	i3c_ccc_cmd_dest_cleanup(&dest);
988 
989 	return ret;
990 }
991 
992 static int i3c_master_setdasa_locked(struct i3c_master_controller *master,
993 				     u8 static_addr, u8 dyn_addr)
994 {
995 	return i3c_master_setda_locked(master, static_addr, dyn_addr, true);
996 }
997 
998 static int i3c_master_setnewda_locked(struct i3c_master_controller *master,
999 				      u8 oldaddr, u8 newaddr)
1000 {
1001 	return i3c_master_setda_locked(master, oldaddr, newaddr, false);
1002 }
1003 
1004 static int i3c_master_getmrl_locked(struct i3c_master_controller *master,
1005 				    struct i3c_device_info *info)
1006 {
1007 	struct i3c_ccc_cmd_dest dest;
1008 	struct i3c_ccc_mrl *mrl;
1009 	struct i3c_ccc_cmd cmd;
1010 	int ret;
1011 
1012 	mrl = i3c_ccc_cmd_dest_init(&dest, info->dyn_addr, sizeof(*mrl));
1013 	if (!mrl)
1014 		return -ENOMEM;
1015 
1016 	/*
1017 	 * When the device does not have IBI payload GETMRL only returns 2
1018 	 * bytes of data.
1019 	 */
1020 	if (!(info->bcr & I3C_BCR_IBI_PAYLOAD))
1021 		dest.payload.len -= 1;
1022 
1023 	i3c_ccc_cmd_init(&cmd, true, I3C_CCC_GETMRL, &dest, 1);
1024 	ret = i3c_master_send_ccc_cmd_locked(master, &cmd);
1025 	if (ret)
1026 		goto out;
1027 
1028 	switch (dest.payload.len) {
1029 	case 3:
1030 		info->max_ibi_len = mrl->ibi_len;
1031 		fallthrough;
1032 	case 2:
1033 		info->max_read_len = be16_to_cpu(mrl->read_len);
1034 		break;
1035 	default:
1036 		ret = -EIO;
1037 		goto out;
1038 	}
1039 
1040 out:
1041 	i3c_ccc_cmd_dest_cleanup(&dest);
1042 
1043 	return ret;
1044 }
1045 
1046 static int i3c_master_getmwl_locked(struct i3c_master_controller *master,
1047 				    struct i3c_device_info *info)
1048 {
1049 	struct i3c_ccc_cmd_dest dest;
1050 	struct i3c_ccc_mwl *mwl;
1051 	struct i3c_ccc_cmd cmd;
1052 	int ret;
1053 
1054 	mwl = i3c_ccc_cmd_dest_init(&dest, info->dyn_addr, sizeof(*mwl));
1055 	if (!mwl)
1056 		return -ENOMEM;
1057 
1058 	i3c_ccc_cmd_init(&cmd, true, I3C_CCC_GETMWL, &dest, 1);
1059 	ret = i3c_master_send_ccc_cmd_locked(master, &cmd);
1060 	if (ret)
1061 		goto out;
1062 
1063 	if (dest.payload.len != sizeof(*mwl)) {
1064 		ret = -EIO;
1065 		goto out;
1066 	}
1067 
1068 	info->max_write_len = be16_to_cpu(mwl->len);
1069 
1070 out:
1071 	i3c_ccc_cmd_dest_cleanup(&dest);
1072 
1073 	return ret;
1074 }
1075 
1076 static int i3c_master_getmxds_locked(struct i3c_master_controller *master,
1077 				     struct i3c_device_info *info)
1078 {
1079 	struct i3c_ccc_getmxds *getmaxds;
1080 	struct i3c_ccc_cmd_dest dest;
1081 	struct i3c_ccc_cmd cmd;
1082 	int ret;
1083 
1084 	getmaxds = i3c_ccc_cmd_dest_init(&dest, info->dyn_addr,
1085 					 sizeof(*getmaxds));
1086 	if (!getmaxds)
1087 		return -ENOMEM;
1088 
1089 	i3c_ccc_cmd_init(&cmd, true, I3C_CCC_GETMXDS, &dest, 1);
1090 	ret = i3c_master_send_ccc_cmd_locked(master, &cmd);
1091 	if (ret)
1092 		goto out;
1093 
1094 	if (dest.payload.len != 2 && dest.payload.len != 5) {
1095 		ret = -EIO;
1096 		goto out;
1097 	}
1098 
1099 	info->max_read_ds = getmaxds->maxrd;
1100 	info->max_write_ds = getmaxds->maxwr;
1101 	if (dest.payload.len == 5)
1102 		info->max_read_turnaround = getmaxds->maxrdturn[0] |
1103 					    ((u32)getmaxds->maxrdturn[1] << 8) |
1104 					    ((u32)getmaxds->maxrdturn[2] << 16);
1105 
1106 out:
1107 	i3c_ccc_cmd_dest_cleanup(&dest);
1108 
1109 	return ret;
1110 }
1111 
1112 static int i3c_master_gethdrcap_locked(struct i3c_master_controller *master,
1113 				       struct i3c_device_info *info)
1114 {
1115 	struct i3c_ccc_gethdrcap *gethdrcap;
1116 	struct i3c_ccc_cmd_dest dest;
1117 	struct i3c_ccc_cmd cmd;
1118 	int ret;
1119 
1120 	gethdrcap = i3c_ccc_cmd_dest_init(&dest, info->dyn_addr,
1121 					  sizeof(*gethdrcap));
1122 	if (!gethdrcap)
1123 		return -ENOMEM;
1124 
1125 	i3c_ccc_cmd_init(&cmd, true, I3C_CCC_GETHDRCAP, &dest, 1);
1126 	ret = i3c_master_send_ccc_cmd_locked(master, &cmd);
1127 	if (ret)
1128 		goto out;
1129 
1130 	if (dest.payload.len != 1) {
1131 		ret = -EIO;
1132 		goto out;
1133 	}
1134 
1135 	info->hdr_cap = gethdrcap->modes;
1136 
1137 out:
1138 	i3c_ccc_cmd_dest_cleanup(&dest);
1139 
1140 	return ret;
1141 }
1142 
1143 static int i3c_master_getpid_locked(struct i3c_master_controller *master,
1144 				    struct i3c_device_info *info)
1145 {
1146 	struct i3c_ccc_getpid *getpid;
1147 	struct i3c_ccc_cmd_dest dest;
1148 	struct i3c_ccc_cmd cmd;
1149 	int ret, i;
1150 
1151 	getpid = i3c_ccc_cmd_dest_init(&dest, info->dyn_addr, sizeof(*getpid));
1152 	if (!getpid)
1153 		return -ENOMEM;
1154 
1155 	i3c_ccc_cmd_init(&cmd, true, I3C_CCC_GETPID, &dest, 1);
1156 	ret = i3c_master_send_ccc_cmd_locked(master, &cmd);
1157 	if (ret)
1158 		goto out;
1159 
1160 	info->pid = 0;
1161 	for (i = 0; i < sizeof(getpid->pid); i++) {
1162 		int sft = (sizeof(getpid->pid) - i - 1) * 8;
1163 
1164 		info->pid |= (u64)getpid->pid[i] << sft;
1165 	}
1166 
1167 out:
1168 	i3c_ccc_cmd_dest_cleanup(&dest);
1169 
1170 	return ret;
1171 }
1172 
1173 static int i3c_master_getbcr_locked(struct i3c_master_controller *master,
1174 				    struct i3c_device_info *info)
1175 {
1176 	struct i3c_ccc_getbcr *getbcr;
1177 	struct i3c_ccc_cmd_dest dest;
1178 	struct i3c_ccc_cmd cmd;
1179 	int ret;
1180 
1181 	getbcr = i3c_ccc_cmd_dest_init(&dest, info->dyn_addr, sizeof(*getbcr));
1182 	if (!getbcr)
1183 		return -ENOMEM;
1184 
1185 	i3c_ccc_cmd_init(&cmd, true, I3C_CCC_GETBCR, &dest, 1);
1186 	ret = i3c_master_send_ccc_cmd_locked(master, &cmd);
1187 	if (ret)
1188 		goto out;
1189 
1190 	info->bcr = getbcr->bcr;
1191 
1192 out:
1193 	i3c_ccc_cmd_dest_cleanup(&dest);
1194 
1195 	return ret;
1196 }
1197 
1198 static int i3c_master_getdcr_locked(struct i3c_master_controller *master,
1199 				    struct i3c_device_info *info)
1200 {
1201 	struct i3c_ccc_getdcr *getdcr;
1202 	struct i3c_ccc_cmd_dest dest;
1203 	struct i3c_ccc_cmd cmd;
1204 	int ret;
1205 
1206 	getdcr = i3c_ccc_cmd_dest_init(&dest, info->dyn_addr, sizeof(*getdcr));
1207 	if (!getdcr)
1208 		return -ENOMEM;
1209 
1210 	i3c_ccc_cmd_init(&cmd, true, I3C_CCC_GETDCR, &dest, 1);
1211 	ret = i3c_master_send_ccc_cmd_locked(master, &cmd);
1212 	if (ret)
1213 		goto out;
1214 
1215 	info->dcr = getdcr->dcr;
1216 
1217 out:
1218 	i3c_ccc_cmd_dest_cleanup(&dest);
1219 
1220 	return ret;
1221 }
1222 
1223 static int i3c_master_retrieve_dev_info(struct i3c_dev_desc *dev)
1224 {
1225 	struct i3c_master_controller *master = i3c_dev_get_master(dev);
1226 	enum i3c_addr_slot_status slot_status;
1227 	int ret;
1228 
1229 	if (!dev->info.dyn_addr)
1230 		return -EINVAL;
1231 
1232 	slot_status = i3c_bus_get_addr_slot_status(&master->bus,
1233 						   dev->info.dyn_addr);
1234 	if (slot_status == I3C_ADDR_SLOT_RSVD ||
1235 	    slot_status == I3C_ADDR_SLOT_I2C_DEV)
1236 		return -EINVAL;
1237 
1238 	ret = i3c_master_getpid_locked(master, &dev->info);
1239 	if (ret)
1240 		return ret;
1241 
1242 	ret = i3c_master_getbcr_locked(master, &dev->info);
1243 	if (ret)
1244 		return ret;
1245 
1246 	ret = i3c_master_getdcr_locked(master, &dev->info);
1247 	if (ret)
1248 		return ret;
1249 
1250 	if (dev->info.bcr & I3C_BCR_MAX_DATA_SPEED_LIM) {
1251 		ret = i3c_master_getmxds_locked(master, &dev->info);
1252 		if (ret)
1253 			return ret;
1254 	}
1255 
1256 	if (dev->info.bcr & I3C_BCR_IBI_PAYLOAD)
1257 		dev->info.max_ibi_len = 1;
1258 
1259 	i3c_master_getmrl_locked(master, &dev->info);
1260 	i3c_master_getmwl_locked(master, &dev->info);
1261 
1262 	if (dev->info.bcr & I3C_BCR_HDR_CAP) {
1263 		ret = i3c_master_gethdrcap_locked(master, &dev->info);
1264 		if (ret)
1265 			return ret;
1266 	}
1267 
1268 	return 0;
1269 }
1270 
1271 static void i3c_master_put_i3c_addrs(struct i3c_dev_desc *dev)
1272 {
1273 	struct i3c_master_controller *master = i3c_dev_get_master(dev);
1274 
1275 	if (dev->info.static_addr)
1276 		i3c_bus_set_addr_slot_status(&master->bus,
1277 					     dev->info.static_addr,
1278 					     I3C_ADDR_SLOT_FREE);
1279 
1280 	if (dev->info.dyn_addr)
1281 		i3c_bus_set_addr_slot_status(&master->bus, dev->info.dyn_addr,
1282 					     I3C_ADDR_SLOT_FREE);
1283 
1284 	if (dev->boardinfo && dev->boardinfo->init_dyn_addr)
1285 		i3c_bus_set_addr_slot_status(&master->bus, dev->info.dyn_addr,
1286 					     I3C_ADDR_SLOT_FREE);
1287 }
1288 
1289 static int i3c_master_get_i3c_addrs(struct i3c_dev_desc *dev)
1290 {
1291 	struct i3c_master_controller *master = i3c_dev_get_master(dev);
1292 	enum i3c_addr_slot_status status;
1293 
1294 	if (!dev->info.static_addr && !dev->info.dyn_addr)
1295 		return 0;
1296 
1297 	if (dev->info.static_addr) {
1298 		status = i3c_bus_get_addr_slot_status(&master->bus,
1299 						      dev->info.static_addr);
1300 		if (status != I3C_ADDR_SLOT_FREE)
1301 			return -EBUSY;
1302 
1303 		i3c_bus_set_addr_slot_status(&master->bus,
1304 					     dev->info.static_addr,
1305 					     I3C_ADDR_SLOT_I3C_DEV);
1306 	}
1307 
1308 	/*
1309 	 * ->init_dyn_addr should have been reserved before that, so, if we're
1310 	 * trying to apply a pre-reserved dynamic address, we should not try
1311 	 * to reserve the address slot a second time.
1312 	 */
1313 	if (dev->info.dyn_addr &&
1314 	    (!dev->boardinfo ||
1315 	     dev->boardinfo->init_dyn_addr != dev->info.dyn_addr)) {
1316 		status = i3c_bus_get_addr_slot_status(&master->bus,
1317 						      dev->info.dyn_addr);
1318 		if (status != I3C_ADDR_SLOT_FREE)
1319 			goto err_release_static_addr;
1320 
1321 		i3c_bus_set_addr_slot_status(&master->bus, dev->info.dyn_addr,
1322 					     I3C_ADDR_SLOT_I3C_DEV);
1323 	}
1324 
1325 	return 0;
1326 
1327 err_release_static_addr:
1328 	if (dev->info.static_addr)
1329 		i3c_bus_set_addr_slot_status(&master->bus,
1330 					     dev->info.static_addr,
1331 					     I3C_ADDR_SLOT_FREE);
1332 
1333 	return -EBUSY;
1334 }
1335 
1336 static int i3c_master_attach_i3c_dev(struct i3c_master_controller *master,
1337 				     struct i3c_dev_desc *dev)
1338 {
1339 	int ret;
1340 
1341 	/*
1342 	 * We don't attach devices to the controller until they are
1343 	 * addressable on the bus.
1344 	 */
1345 	if (!dev->info.static_addr && !dev->info.dyn_addr)
1346 		return 0;
1347 
1348 	ret = i3c_master_get_i3c_addrs(dev);
1349 	if (ret)
1350 		return ret;
1351 
1352 	/* Do not attach the master device itself. */
1353 	if (master->this != dev && master->ops->attach_i3c_dev) {
1354 		ret = master->ops->attach_i3c_dev(dev);
1355 		if (ret) {
1356 			i3c_master_put_i3c_addrs(dev);
1357 			return ret;
1358 		}
1359 	}
1360 
1361 	list_add_tail(&dev->common.node, &master->bus.devs.i3c);
1362 
1363 	return 0;
1364 }
1365 
1366 static int i3c_master_reattach_i3c_dev(struct i3c_dev_desc *dev,
1367 				       u8 old_dyn_addr)
1368 {
1369 	struct i3c_master_controller *master = i3c_dev_get_master(dev);
1370 	enum i3c_addr_slot_status status;
1371 	int ret;
1372 
1373 	if (dev->info.dyn_addr != old_dyn_addr &&
1374 	    (!dev->boardinfo ||
1375 	     dev->info.dyn_addr != dev->boardinfo->init_dyn_addr)) {
1376 		status = i3c_bus_get_addr_slot_status(&master->bus,
1377 						      dev->info.dyn_addr);
1378 		if (status != I3C_ADDR_SLOT_FREE)
1379 			return -EBUSY;
1380 		i3c_bus_set_addr_slot_status(&master->bus,
1381 					     dev->info.dyn_addr,
1382 					     I3C_ADDR_SLOT_I3C_DEV);
1383 	}
1384 
1385 	if (master->ops->reattach_i3c_dev) {
1386 		ret = master->ops->reattach_i3c_dev(dev, old_dyn_addr);
1387 		if (ret) {
1388 			i3c_master_put_i3c_addrs(dev);
1389 			return ret;
1390 		}
1391 	}
1392 
1393 	return 0;
1394 }
1395 
1396 static void i3c_master_detach_i3c_dev(struct i3c_dev_desc *dev)
1397 {
1398 	struct i3c_master_controller *master = i3c_dev_get_master(dev);
1399 
1400 	/* Do not detach the master device itself. */
1401 	if (master->this != dev && master->ops->detach_i3c_dev)
1402 		master->ops->detach_i3c_dev(dev);
1403 
1404 	i3c_master_put_i3c_addrs(dev);
1405 	list_del(&dev->common.node);
1406 }
1407 
1408 static int i3c_master_attach_i2c_dev(struct i3c_master_controller *master,
1409 				     struct i2c_dev_desc *dev)
1410 {
1411 	int ret;
1412 
1413 	if (master->ops->attach_i2c_dev) {
1414 		ret = master->ops->attach_i2c_dev(dev);
1415 		if (ret)
1416 			return ret;
1417 	}
1418 
1419 	list_add_tail(&dev->common.node, &master->bus.devs.i2c);
1420 
1421 	return 0;
1422 }
1423 
1424 static void i3c_master_detach_i2c_dev(struct i2c_dev_desc *dev)
1425 {
1426 	struct i3c_master_controller *master = i2c_dev_get_master(dev);
1427 
1428 	list_del(&dev->common.node);
1429 
1430 	if (master->ops->detach_i2c_dev)
1431 		master->ops->detach_i2c_dev(dev);
1432 }
1433 
1434 static int i3c_master_early_i3c_dev_add(struct i3c_master_controller *master,
1435 					  struct i3c_dev_boardinfo *boardinfo)
1436 {
1437 	struct i3c_device_info info = {
1438 		.static_addr = boardinfo->static_addr,
1439 	};
1440 	struct i3c_dev_desc *i3cdev;
1441 	int ret;
1442 
1443 	i3cdev = i3c_master_alloc_i3c_dev(master, &info);
1444 	if (IS_ERR(i3cdev))
1445 		return -ENOMEM;
1446 
1447 	i3cdev->boardinfo = boardinfo;
1448 
1449 	ret = i3c_master_attach_i3c_dev(master, i3cdev);
1450 	if (ret)
1451 		goto err_free_dev;
1452 
1453 	ret = i3c_master_setdasa_locked(master, i3cdev->info.static_addr,
1454 					i3cdev->boardinfo->init_dyn_addr);
1455 	if (ret)
1456 		goto err_detach_dev;
1457 
1458 	i3cdev->info.dyn_addr = i3cdev->boardinfo->init_dyn_addr;
1459 	ret = i3c_master_reattach_i3c_dev(i3cdev, 0);
1460 	if (ret)
1461 		goto err_rstdaa;
1462 
1463 	ret = i3c_master_retrieve_dev_info(i3cdev);
1464 	if (ret)
1465 		goto err_rstdaa;
1466 
1467 	return 0;
1468 
1469 err_rstdaa:
1470 	i3c_master_rstdaa_locked(master, i3cdev->boardinfo->init_dyn_addr);
1471 err_detach_dev:
1472 	i3c_master_detach_i3c_dev(i3cdev);
1473 err_free_dev:
1474 	i3c_master_free_i3c_dev(i3cdev);
1475 
1476 	return ret;
1477 }
1478 
1479 static void
1480 i3c_master_register_new_i3c_devs(struct i3c_master_controller *master)
1481 {
1482 	struct i3c_dev_desc *desc;
1483 	int ret;
1484 
1485 	if (!master->init_done)
1486 		return;
1487 
1488 	i3c_bus_for_each_i3cdev(&master->bus, desc) {
1489 		if (desc->dev || !desc->info.dyn_addr || desc == master->this)
1490 			continue;
1491 
1492 		desc->dev = kzalloc(sizeof(*desc->dev), GFP_KERNEL);
1493 		if (!desc->dev)
1494 			continue;
1495 
1496 		desc->dev->bus = &master->bus;
1497 		desc->dev->desc = desc;
1498 		desc->dev->dev.parent = &master->dev;
1499 		desc->dev->dev.type = &i3c_device_type;
1500 		desc->dev->dev.bus = &i3c_bus_type;
1501 		desc->dev->dev.release = i3c_device_release;
1502 		dev_set_name(&desc->dev->dev, "%d-%llx", master->bus.id,
1503 			     desc->info.pid);
1504 
1505 		if (desc->boardinfo)
1506 			desc->dev->dev.of_node = desc->boardinfo->of_node;
1507 
1508 		ret = device_register(&desc->dev->dev);
1509 		if (ret)
1510 			dev_err(&master->dev,
1511 				"Failed to add I3C device (err = %d)\n", ret);
1512 	}
1513 }
1514 
1515 /**
1516  * i3c_master_do_daa() - do a DAA (Dynamic Address Assignment)
1517  * @master: master doing the DAA
1518  *
1519  * This function is instantiating an I3C device object and adding it to the
1520  * I3C device list. All device information are automatically retrieved using
1521  * standard CCC commands.
1522  *
1523  * The I3C device object is returned in case the master wants to attach
1524  * private data to it using i3c_dev_set_master_data().
1525  *
1526  * This function must be called with the bus lock held in write mode.
1527  *
1528  * Return: a 0 in case of success, an negative error code otherwise.
1529  */
1530 int i3c_master_do_daa(struct i3c_master_controller *master)
1531 {
1532 	int ret;
1533 
1534 	i3c_bus_maintenance_lock(&master->bus);
1535 	ret = master->ops->do_daa(master);
1536 	i3c_bus_maintenance_unlock(&master->bus);
1537 
1538 	if (ret)
1539 		return ret;
1540 
1541 	i3c_bus_normaluse_lock(&master->bus);
1542 	i3c_master_register_new_i3c_devs(master);
1543 	i3c_bus_normaluse_unlock(&master->bus);
1544 
1545 	return 0;
1546 }
1547 EXPORT_SYMBOL_GPL(i3c_master_do_daa);
1548 
1549 /**
1550  * i3c_master_set_info() - set master device information
1551  * @master: master used to send frames on the bus
1552  * @info: I3C device information
1553  *
1554  * Set master device info. This should be called from
1555  * &i3c_master_controller_ops->bus_init().
1556  *
1557  * Not all &i3c_device_info fields are meaningful for a master device.
1558  * Here is a list of fields that should be properly filled:
1559  *
1560  * - &i3c_device_info->dyn_addr
1561  * - &i3c_device_info->bcr
1562  * - &i3c_device_info->dcr
1563  * - &i3c_device_info->pid
1564  * - &i3c_device_info->hdr_cap if %I3C_BCR_HDR_CAP bit is set in
1565  *   &i3c_device_info->bcr
1566  *
1567  * This function must be called with the bus lock held in maintenance mode.
1568  *
1569  * Return: 0 if @info contains valid information (not every piece of
1570  * information can be checked, but we can at least make sure @info->dyn_addr
1571  * and @info->bcr are correct), -EINVAL otherwise.
1572  */
1573 int i3c_master_set_info(struct i3c_master_controller *master,
1574 			const struct i3c_device_info *info)
1575 {
1576 	struct i3c_dev_desc *i3cdev;
1577 	int ret;
1578 
1579 	if (!i3c_bus_dev_addr_is_avail(&master->bus, info->dyn_addr))
1580 		return -EINVAL;
1581 
1582 	if (I3C_BCR_DEVICE_ROLE(info->bcr) == I3C_BCR_I3C_MASTER &&
1583 	    master->secondary)
1584 		return -EINVAL;
1585 
1586 	if (master->this)
1587 		return -EINVAL;
1588 
1589 	i3cdev = i3c_master_alloc_i3c_dev(master, info);
1590 	if (IS_ERR(i3cdev))
1591 		return PTR_ERR(i3cdev);
1592 
1593 	master->this = i3cdev;
1594 	master->bus.cur_master = master->this;
1595 
1596 	ret = i3c_master_attach_i3c_dev(master, i3cdev);
1597 	if (ret)
1598 		goto err_free_dev;
1599 
1600 	return 0;
1601 
1602 err_free_dev:
1603 	i3c_master_free_i3c_dev(i3cdev);
1604 
1605 	return ret;
1606 }
1607 EXPORT_SYMBOL_GPL(i3c_master_set_info);
1608 
1609 static void i3c_master_detach_free_devs(struct i3c_master_controller *master)
1610 {
1611 	struct i3c_dev_desc *i3cdev, *i3ctmp;
1612 	struct i2c_dev_desc *i2cdev, *i2ctmp;
1613 
1614 	list_for_each_entry_safe(i3cdev, i3ctmp, &master->bus.devs.i3c,
1615 				 common.node) {
1616 		i3c_master_detach_i3c_dev(i3cdev);
1617 
1618 		if (i3cdev->boardinfo && i3cdev->boardinfo->init_dyn_addr)
1619 			i3c_bus_set_addr_slot_status(&master->bus,
1620 					i3cdev->boardinfo->init_dyn_addr,
1621 					I3C_ADDR_SLOT_FREE);
1622 
1623 		i3c_master_free_i3c_dev(i3cdev);
1624 	}
1625 
1626 	list_for_each_entry_safe(i2cdev, i2ctmp, &master->bus.devs.i2c,
1627 				 common.node) {
1628 		i3c_master_detach_i2c_dev(i2cdev);
1629 		i3c_bus_set_addr_slot_status(&master->bus,
1630 					     i2cdev->addr,
1631 					     I3C_ADDR_SLOT_FREE);
1632 		i3c_master_free_i2c_dev(i2cdev);
1633 	}
1634 }
1635 
1636 /**
1637  * i3c_master_bus_init() - initialize an I3C bus
1638  * @master: main master initializing the bus
1639  *
1640  * This function is following all initialisation steps described in the I3C
1641  * specification:
1642  *
1643  * 1. Attach I2C devs to the master so that the master can fill its internal
1644  *    device table appropriately
1645  *
1646  * 2. Call &i3c_master_controller_ops->bus_init() method to initialize
1647  *    the master controller. That's usually where the bus mode is selected
1648  *    (pure bus or mixed fast/slow bus)
1649  *
1650  * 3. Instruct all devices on the bus to drop their dynamic address. This is
1651  *    particularly important when the bus was previously configured by someone
1652  *    else (for example the bootloader)
1653  *
1654  * 4. Disable all slave events.
1655  *
1656  * 5. Reserve address slots for I3C devices with init_dyn_addr. And if devices
1657  *    also have static_addr, try to pre-assign dynamic addresses requested by
1658  *    the FW with SETDASA and attach corresponding statically defined I3C
1659  *    devices to the master.
1660  *
1661  * 6. Do a DAA (Dynamic Address Assignment) to assign dynamic addresses to all
1662  *    remaining I3C devices
1663  *
1664  * Once this is done, all I3C and I2C devices should be usable.
1665  *
1666  * Return: a 0 in case of success, an negative error code otherwise.
1667  */
1668 static int i3c_master_bus_init(struct i3c_master_controller *master)
1669 {
1670 	enum i3c_addr_slot_status status;
1671 	struct i2c_dev_boardinfo *i2cboardinfo;
1672 	struct i3c_dev_boardinfo *i3cboardinfo;
1673 	struct i2c_dev_desc *i2cdev;
1674 	int ret;
1675 
1676 	/*
1677 	 * First attach all devices with static definitions provided by the
1678 	 * FW.
1679 	 */
1680 	list_for_each_entry(i2cboardinfo, &master->boardinfo.i2c, node) {
1681 		status = i3c_bus_get_addr_slot_status(&master->bus,
1682 						      i2cboardinfo->base.addr);
1683 		if (status != I3C_ADDR_SLOT_FREE) {
1684 			ret = -EBUSY;
1685 			goto err_detach_devs;
1686 		}
1687 
1688 		i3c_bus_set_addr_slot_status(&master->bus,
1689 					     i2cboardinfo->base.addr,
1690 					     I3C_ADDR_SLOT_I2C_DEV);
1691 
1692 		i2cdev = i3c_master_alloc_i2c_dev(master, i2cboardinfo);
1693 		if (IS_ERR(i2cdev)) {
1694 			ret = PTR_ERR(i2cdev);
1695 			goto err_detach_devs;
1696 		}
1697 
1698 		ret = i3c_master_attach_i2c_dev(master, i2cdev);
1699 		if (ret) {
1700 			i3c_master_free_i2c_dev(i2cdev);
1701 			goto err_detach_devs;
1702 		}
1703 	}
1704 
1705 	/*
1706 	 * Now execute the controller specific ->bus_init() routine, which
1707 	 * might configure its internal logic to match the bus limitations.
1708 	 */
1709 	ret = master->ops->bus_init(master);
1710 	if (ret)
1711 		goto err_detach_devs;
1712 
1713 	/*
1714 	 * The master device should have been instantiated in ->bus_init(),
1715 	 * complain if this was not the case.
1716 	 */
1717 	if (!master->this) {
1718 		dev_err(&master->dev,
1719 			"master_set_info() was not called in ->bus_init()\n");
1720 		ret = -EINVAL;
1721 		goto err_bus_cleanup;
1722 	}
1723 
1724 	/*
1725 	 * Reset all dynamic address that may have been assigned before
1726 	 * (assigned by the bootloader for example).
1727 	 */
1728 	ret = i3c_master_rstdaa_locked(master, I3C_BROADCAST_ADDR);
1729 	if (ret && ret != I3C_ERROR_M2)
1730 		goto err_bus_cleanup;
1731 
1732 	/* Disable all slave events before starting DAA. */
1733 	ret = i3c_master_disec_locked(master, I3C_BROADCAST_ADDR,
1734 				      I3C_CCC_EVENT_SIR | I3C_CCC_EVENT_MR |
1735 				      I3C_CCC_EVENT_HJ);
1736 	if (ret && ret != I3C_ERROR_M2)
1737 		goto err_bus_cleanup;
1738 
1739 	/*
1740 	 * Reserve init_dyn_addr first, and then try to pre-assign dynamic
1741 	 * address and retrieve device information if needed.
1742 	 * In case pre-assign dynamic address fails, setting dynamic address to
1743 	 * the requested init_dyn_addr is retried after DAA is done in
1744 	 * i3c_master_add_i3c_dev_locked().
1745 	 */
1746 	list_for_each_entry(i3cboardinfo, &master->boardinfo.i3c, node) {
1747 
1748 		/*
1749 		 * We don't reserve a dynamic address for devices that
1750 		 * don't explicitly request one.
1751 		 */
1752 		if (!i3cboardinfo->init_dyn_addr)
1753 			continue;
1754 
1755 		ret = i3c_bus_get_addr_slot_status(&master->bus,
1756 						   i3cboardinfo->init_dyn_addr);
1757 		if (ret != I3C_ADDR_SLOT_FREE) {
1758 			ret = -EBUSY;
1759 			goto err_rstdaa;
1760 		}
1761 
1762 		i3c_bus_set_addr_slot_status(&master->bus,
1763 					     i3cboardinfo->init_dyn_addr,
1764 					     I3C_ADDR_SLOT_I3C_DEV);
1765 
1766 		/*
1767 		 * Only try to create/attach devices that have a static
1768 		 * address. Other devices will be created/attached when
1769 		 * DAA happens, and the requested dynamic address will
1770 		 * be set using SETNEWDA once those devices become
1771 		 * addressable.
1772 		 */
1773 
1774 		if (i3cboardinfo->static_addr)
1775 			i3c_master_early_i3c_dev_add(master, i3cboardinfo);
1776 	}
1777 
1778 	ret = i3c_master_do_daa(master);
1779 	if (ret)
1780 		goto err_rstdaa;
1781 
1782 	return 0;
1783 
1784 err_rstdaa:
1785 	i3c_master_rstdaa_locked(master, I3C_BROADCAST_ADDR);
1786 
1787 err_bus_cleanup:
1788 	if (master->ops->bus_cleanup)
1789 		master->ops->bus_cleanup(master);
1790 
1791 err_detach_devs:
1792 	i3c_master_detach_free_devs(master);
1793 
1794 	return ret;
1795 }
1796 
1797 static void i3c_master_bus_cleanup(struct i3c_master_controller *master)
1798 {
1799 	if (master->ops->bus_cleanup)
1800 		master->ops->bus_cleanup(master);
1801 
1802 	i3c_master_detach_free_devs(master);
1803 }
1804 
1805 static void i3c_master_attach_boardinfo(struct i3c_dev_desc *i3cdev)
1806 {
1807 	struct i3c_master_controller *master = i3cdev->common.master;
1808 	struct i3c_dev_boardinfo *i3cboardinfo;
1809 
1810 	list_for_each_entry(i3cboardinfo, &master->boardinfo.i3c, node) {
1811 		if (i3cdev->info.pid != i3cboardinfo->pid)
1812 			continue;
1813 
1814 		i3cdev->boardinfo = i3cboardinfo;
1815 		i3cdev->info.static_addr = i3cboardinfo->static_addr;
1816 		return;
1817 	}
1818 }
1819 
1820 static struct i3c_dev_desc *
1821 i3c_master_search_i3c_dev_duplicate(struct i3c_dev_desc *refdev)
1822 {
1823 	struct i3c_master_controller *master = i3c_dev_get_master(refdev);
1824 	struct i3c_dev_desc *i3cdev;
1825 
1826 	i3c_bus_for_each_i3cdev(&master->bus, i3cdev) {
1827 		if (i3cdev != refdev && i3cdev->info.pid == refdev->info.pid)
1828 			return i3cdev;
1829 	}
1830 
1831 	return NULL;
1832 }
1833 
1834 /**
1835  * i3c_master_add_i3c_dev_locked() - add an I3C slave to the bus
1836  * @master: master used to send frames on the bus
1837  * @addr: I3C slave dynamic address assigned to the device
1838  *
1839  * This function is instantiating an I3C device object and adding it to the
1840  * I3C device list. All device information are automatically retrieved using
1841  * standard CCC commands.
1842  *
1843  * The I3C device object is returned in case the master wants to attach
1844  * private data to it using i3c_dev_set_master_data().
1845  *
1846  * This function must be called with the bus lock held in write mode.
1847  *
1848  * Return: a 0 in case of success, an negative error code otherwise.
1849  */
1850 int i3c_master_add_i3c_dev_locked(struct i3c_master_controller *master,
1851 				  u8 addr)
1852 {
1853 	struct i3c_device_info info = { .dyn_addr = addr };
1854 	struct i3c_dev_desc *newdev, *olddev;
1855 	u8 old_dyn_addr = addr, expected_dyn_addr;
1856 	struct i3c_ibi_setup ibireq = { };
1857 	bool enable_ibi = false;
1858 	int ret;
1859 
1860 	if (!master)
1861 		return -EINVAL;
1862 
1863 	newdev = i3c_master_alloc_i3c_dev(master, &info);
1864 	if (IS_ERR(newdev))
1865 		return PTR_ERR(newdev);
1866 
1867 	ret = i3c_master_attach_i3c_dev(master, newdev);
1868 	if (ret)
1869 		goto err_free_dev;
1870 
1871 	ret = i3c_master_retrieve_dev_info(newdev);
1872 	if (ret)
1873 		goto err_detach_dev;
1874 
1875 	i3c_master_attach_boardinfo(newdev);
1876 
1877 	olddev = i3c_master_search_i3c_dev_duplicate(newdev);
1878 	if (olddev) {
1879 		newdev->dev = olddev->dev;
1880 		if (newdev->dev)
1881 			newdev->dev->desc = newdev;
1882 
1883 		/*
1884 		 * We need to restore the IBI state too, so let's save the
1885 		 * IBI information and try to restore them after olddev has
1886 		 * been detached+released and its IBI has been stopped and
1887 		 * the associated resources have been freed.
1888 		 */
1889 		mutex_lock(&olddev->ibi_lock);
1890 		if (olddev->ibi) {
1891 			ibireq.handler = olddev->ibi->handler;
1892 			ibireq.max_payload_len = olddev->ibi->max_payload_len;
1893 			ibireq.num_slots = olddev->ibi->num_slots;
1894 
1895 			if (olddev->ibi->enabled) {
1896 				enable_ibi = true;
1897 				i3c_dev_disable_ibi_locked(olddev);
1898 			}
1899 
1900 			i3c_dev_free_ibi_locked(olddev);
1901 		}
1902 		mutex_unlock(&olddev->ibi_lock);
1903 
1904 		old_dyn_addr = olddev->info.dyn_addr;
1905 
1906 		i3c_master_detach_i3c_dev(olddev);
1907 		i3c_master_free_i3c_dev(olddev);
1908 	}
1909 
1910 	ret = i3c_master_reattach_i3c_dev(newdev, old_dyn_addr);
1911 	if (ret)
1912 		goto err_detach_dev;
1913 
1914 	/*
1915 	 * Depending on our previous state, the expected dynamic address might
1916 	 * differ:
1917 	 * - if the device already had a dynamic address assigned, let's try to
1918 	 *   re-apply this one
1919 	 * - if the device did not have a dynamic address and the firmware
1920 	 *   requested a specific address, pick this one
1921 	 * - in any other case, keep the address automatically assigned by the
1922 	 *   master
1923 	 */
1924 	if (old_dyn_addr && old_dyn_addr != newdev->info.dyn_addr)
1925 		expected_dyn_addr = old_dyn_addr;
1926 	else if (newdev->boardinfo && newdev->boardinfo->init_dyn_addr)
1927 		expected_dyn_addr = newdev->boardinfo->init_dyn_addr;
1928 	else
1929 		expected_dyn_addr = newdev->info.dyn_addr;
1930 
1931 	if (newdev->info.dyn_addr != expected_dyn_addr) {
1932 		/*
1933 		 * Try to apply the expected dynamic address. If it fails, keep
1934 		 * the address assigned by the master.
1935 		 */
1936 		ret = i3c_master_setnewda_locked(master,
1937 						 newdev->info.dyn_addr,
1938 						 expected_dyn_addr);
1939 		if (!ret) {
1940 			old_dyn_addr = newdev->info.dyn_addr;
1941 			newdev->info.dyn_addr = expected_dyn_addr;
1942 			i3c_master_reattach_i3c_dev(newdev, old_dyn_addr);
1943 		} else {
1944 			dev_err(&master->dev,
1945 				"Failed to assign reserved/old address to device %d%llx",
1946 				master->bus.id, newdev->info.pid);
1947 		}
1948 	}
1949 
1950 	/*
1951 	 * Now is time to try to restore the IBI setup. If we're lucky,
1952 	 * everything works as before, otherwise, all we can do is complain.
1953 	 * FIXME: maybe we should add callback to inform the driver that it
1954 	 * should request the IBI again instead of trying to hide that from
1955 	 * him.
1956 	 */
1957 	if (ibireq.handler) {
1958 		mutex_lock(&newdev->ibi_lock);
1959 		ret = i3c_dev_request_ibi_locked(newdev, &ibireq);
1960 		if (ret) {
1961 			dev_err(&master->dev,
1962 				"Failed to request IBI on device %d-%llx",
1963 				master->bus.id, newdev->info.pid);
1964 		} else if (enable_ibi) {
1965 			ret = i3c_dev_enable_ibi_locked(newdev);
1966 			if (ret)
1967 				dev_err(&master->dev,
1968 					"Failed to re-enable IBI on device %d-%llx",
1969 					master->bus.id, newdev->info.pid);
1970 		}
1971 		mutex_unlock(&newdev->ibi_lock);
1972 	}
1973 
1974 	return 0;
1975 
1976 err_detach_dev:
1977 	if (newdev->dev && newdev->dev->desc)
1978 		newdev->dev->desc = NULL;
1979 
1980 	i3c_master_detach_i3c_dev(newdev);
1981 
1982 err_free_dev:
1983 	i3c_master_free_i3c_dev(newdev);
1984 
1985 	return ret;
1986 }
1987 EXPORT_SYMBOL_GPL(i3c_master_add_i3c_dev_locked);
1988 
1989 #define OF_I3C_REG1_IS_I2C_DEV			BIT(31)
1990 
1991 static int
1992 of_i3c_master_add_i2c_boardinfo(struct i3c_master_controller *master,
1993 				struct device_node *node, u32 *reg)
1994 {
1995 	struct i2c_dev_boardinfo *boardinfo;
1996 	struct device *dev = &master->dev;
1997 	int ret;
1998 
1999 	boardinfo = devm_kzalloc(dev, sizeof(*boardinfo), GFP_KERNEL);
2000 	if (!boardinfo)
2001 		return -ENOMEM;
2002 
2003 	ret = of_i2c_get_board_info(dev, node, &boardinfo->base);
2004 	if (ret)
2005 		return ret;
2006 
2007 	/*
2008 	 * The I3C Specification does not clearly say I2C devices with 10-bit
2009 	 * address are supported. These devices can't be passed properly through
2010 	 * DEFSLVS command.
2011 	 */
2012 	if (boardinfo->base.flags & I2C_CLIENT_TEN) {
2013 		dev_err(dev, "I2C device with 10 bit address not supported.");
2014 		return -ENOTSUPP;
2015 	}
2016 
2017 	/* LVR is encoded in reg[2]. */
2018 	boardinfo->lvr = reg[2];
2019 
2020 	list_add_tail(&boardinfo->node, &master->boardinfo.i2c);
2021 	of_node_get(node);
2022 
2023 	return 0;
2024 }
2025 
2026 static int
2027 of_i3c_master_add_i3c_boardinfo(struct i3c_master_controller *master,
2028 				struct device_node *node, u32 *reg)
2029 {
2030 	struct i3c_dev_boardinfo *boardinfo;
2031 	struct device *dev = &master->dev;
2032 	enum i3c_addr_slot_status addrstatus;
2033 	u32 init_dyn_addr = 0;
2034 
2035 	boardinfo = devm_kzalloc(dev, sizeof(*boardinfo), GFP_KERNEL);
2036 	if (!boardinfo)
2037 		return -ENOMEM;
2038 
2039 	if (reg[0]) {
2040 		if (reg[0] > I3C_MAX_ADDR)
2041 			return -EINVAL;
2042 
2043 		addrstatus = i3c_bus_get_addr_slot_status(&master->bus,
2044 							  reg[0]);
2045 		if (addrstatus != I3C_ADDR_SLOT_FREE)
2046 			return -EINVAL;
2047 	}
2048 
2049 	boardinfo->static_addr = reg[0];
2050 
2051 	if (!of_property_read_u32(node, "assigned-address", &init_dyn_addr)) {
2052 		if (init_dyn_addr > I3C_MAX_ADDR)
2053 			return -EINVAL;
2054 
2055 		addrstatus = i3c_bus_get_addr_slot_status(&master->bus,
2056 							  init_dyn_addr);
2057 		if (addrstatus != I3C_ADDR_SLOT_FREE)
2058 			return -EINVAL;
2059 	}
2060 
2061 	boardinfo->pid = ((u64)reg[1] << 32) | reg[2];
2062 
2063 	if ((boardinfo->pid & GENMASK_ULL(63, 48)) ||
2064 	    I3C_PID_RND_LOWER_32BITS(boardinfo->pid))
2065 		return -EINVAL;
2066 
2067 	boardinfo->init_dyn_addr = init_dyn_addr;
2068 	boardinfo->of_node = of_node_get(node);
2069 	list_add_tail(&boardinfo->node, &master->boardinfo.i3c);
2070 
2071 	return 0;
2072 }
2073 
2074 static int of_i3c_master_add_dev(struct i3c_master_controller *master,
2075 				 struct device_node *node)
2076 {
2077 	u32 reg[3];
2078 	int ret;
2079 
2080 	if (!master || !node)
2081 		return -EINVAL;
2082 
2083 	ret = of_property_read_u32_array(node, "reg", reg, ARRAY_SIZE(reg));
2084 	if (ret)
2085 		return ret;
2086 
2087 	/*
2088 	 * The manufacturer ID can't be 0. If reg[1] == 0 that means we're
2089 	 * dealing with an I2C device.
2090 	 */
2091 	if (!reg[1])
2092 		ret = of_i3c_master_add_i2c_boardinfo(master, node, reg);
2093 	else
2094 		ret = of_i3c_master_add_i3c_boardinfo(master, node, reg);
2095 
2096 	return ret;
2097 }
2098 
2099 static int of_populate_i3c_bus(struct i3c_master_controller *master)
2100 {
2101 	struct device *dev = &master->dev;
2102 	struct device_node *i3cbus_np = dev->of_node;
2103 	struct device_node *node;
2104 	int ret;
2105 	u32 val;
2106 
2107 	if (!i3cbus_np)
2108 		return 0;
2109 
2110 	for_each_available_child_of_node(i3cbus_np, node) {
2111 		ret = of_i3c_master_add_dev(master, node);
2112 		if (ret) {
2113 			of_node_put(node);
2114 			return ret;
2115 		}
2116 	}
2117 
2118 	/*
2119 	 * The user might want to limit I2C and I3C speed in case some devices
2120 	 * on the bus are not supporting typical rates, or if the bus topology
2121 	 * prevents it from using max possible rate.
2122 	 */
2123 	if (!of_property_read_u32(i3cbus_np, "i2c-scl-hz", &val))
2124 		master->bus.scl_rate.i2c = val;
2125 
2126 	if (!of_property_read_u32(i3cbus_np, "i3c-scl-hz", &val))
2127 		master->bus.scl_rate.i3c = val;
2128 
2129 	return 0;
2130 }
2131 
2132 static int i3c_master_i2c_adapter_xfer(struct i2c_adapter *adap,
2133 				       struct i2c_msg *xfers, int nxfers)
2134 {
2135 	struct i3c_master_controller *master = i2c_adapter_to_i3c_master(adap);
2136 	struct i2c_dev_desc *dev;
2137 	int i, ret;
2138 	u16 addr;
2139 
2140 	if (!xfers || !master || nxfers <= 0)
2141 		return -EINVAL;
2142 
2143 	if (!master->ops->i2c_xfers)
2144 		return -ENOTSUPP;
2145 
2146 	/* Doing transfers to different devices is not supported. */
2147 	addr = xfers[0].addr;
2148 	for (i = 1; i < nxfers; i++) {
2149 		if (addr != xfers[i].addr)
2150 			return -ENOTSUPP;
2151 	}
2152 
2153 	i3c_bus_normaluse_lock(&master->bus);
2154 	dev = i3c_master_find_i2c_dev_by_addr(master, addr);
2155 	if (!dev)
2156 		ret = -ENOENT;
2157 	else
2158 		ret = master->ops->i2c_xfers(dev, xfers, nxfers);
2159 	i3c_bus_normaluse_unlock(&master->bus);
2160 
2161 	return ret ? ret : nxfers;
2162 }
2163 
2164 static u32 i3c_master_i2c_funcs(struct i2c_adapter *adapter)
2165 {
2166 	return I2C_FUNC_SMBUS_EMUL | I2C_FUNC_I2C;
2167 }
2168 
2169 static const struct i2c_algorithm i3c_master_i2c_algo = {
2170 	.master_xfer = i3c_master_i2c_adapter_xfer,
2171 	.functionality = i3c_master_i2c_funcs,
2172 };
2173 
2174 static int i3c_master_i2c_adapter_init(struct i3c_master_controller *master)
2175 {
2176 	struct i2c_adapter *adap = i3c_master_to_i2c_adapter(master);
2177 	struct i2c_dev_desc *i2cdev;
2178 	int ret;
2179 
2180 	adap->dev.parent = master->dev.parent;
2181 	adap->owner = master->dev.parent->driver->owner;
2182 	adap->algo = &i3c_master_i2c_algo;
2183 	strncpy(adap->name, dev_name(master->dev.parent), sizeof(adap->name));
2184 
2185 	/* FIXME: Should we allow i3c masters to override these values? */
2186 	adap->timeout = 1000;
2187 	adap->retries = 3;
2188 
2189 	ret = i2c_add_adapter(adap);
2190 	if (ret)
2191 		return ret;
2192 
2193 	/*
2194 	 * We silently ignore failures here. The bus should keep working
2195 	 * correctly even if one or more i2c devices are not registered.
2196 	 */
2197 	i3c_bus_for_each_i2cdev(&master->bus, i2cdev)
2198 		i2cdev->dev = i2c_new_client_device(adap, &i2cdev->boardinfo->base);
2199 
2200 	return 0;
2201 }
2202 
2203 static void i3c_master_i2c_adapter_cleanup(struct i3c_master_controller *master)
2204 {
2205 	struct i2c_dev_desc *i2cdev;
2206 
2207 	i2c_del_adapter(&master->i2c);
2208 
2209 	i3c_bus_for_each_i2cdev(&master->bus, i2cdev)
2210 		i2cdev->dev = NULL;
2211 }
2212 
2213 static void i3c_master_unregister_i3c_devs(struct i3c_master_controller *master)
2214 {
2215 	struct i3c_dev_desc *i3cdev;
2216 
2217 	i3c_bus_for_each_i3cdev(&master->bus, i3cdev) {
2218 		if (!i3cdev->dev)
2219 			continue;
2220 
2221 		i3cdev->dev->desc = NULL;
2222 		if (device_is_registered(&i3cdev->dev->dev))
2223 			device_unregister(&i3cdev->dev->dev);
2224 		else
2225 			put_device(&i3cdev->dev->dev);
2226 		i3cdev->dev = NULL;
2227 	}
2228 }
2229 
2230 /**
2231  * i3c_master_queue_ibi() - Queue an IBI
2232  * @dev: the device this IBI is coming from
2233  * @slot: the IBI slot used to store the payload
2234  *
2235  * Queue an IBI to the controller workqueue. The IBI handler attached to
2236  * the dev will be called from a workqueue context.
2237  */
2238 void i3c_master_queue_ibi(struct i3c_dev_desc *dev, struct i3c_ibi_slot *slot)
2239 {
2240 	atomic_inc(&dev->ibi->pending_ibis);
2241 	queue_work(dev->common.master->wq, &slot->work);
2242 }
2243 EXPORT_SYMBOL_GPL(i3c_master_queue_ibi);
2244 
2245 static void i3c_master_handle_ibi(struct work_struct *work)
2246 {
2247 	struct i3c_ibi_slot *slot = container_of(work, struct i3c_ibi_slot,
2248 						 work);
2249 	struct i3c_dev_desc *dev = slot->dev;
2250 	struct i3c_master_controller *master = i3c_dev_get_master(dev);
2251 	struct i3c_ibi_payload payload;
2252 
2253 	payload.data = slot->data;
2254 	payload.len = slot->len;
2255 
2256 	if (dev->dev)
2257 		dev->ibi->handler(dev->dev, &payload);
2258 
2259 	master->ops->recycle_ibi_slot(dev, slot);
2260 	if (atomic_dec_and_test(&dev->ibi->pending_ibis))
2261 		complete(&dev->ibi->all_ibis_handled);
2262 }
2263 
2264 static void i3c_master_init_ibi_slot(struct i3c_dev_desc *dev,
2265 				     struct i3c_ibi_slot *slot)
2266 {
2267 	slot->dev = dev;
2268 	INIT_WORK(&slot->work, i3c_master_handle_ibi);
2269 }
2270 
2271 struct i3c_generic_ibi_slot {
2272 	struct list_head node;
2273 	struct i3c_ibi_slot base;
2274 };
2275 
2276 struct i3c_generic_ibi_pool {
2277 	spinlock_t lock;
2278 	unsigned int num_slots;
2279 	struct i3c_generic_ibi_slot *slots;
2280 	void *payload_buf;
2281 	struct list_head free_slots;
2282 	struct list_head pending;
2283 };
2284 
2285 /**
2286  * i3c_generic_ibi_free_pool() - Free a generic IBI pool
2287  * @pool: the IBI pool to free
2288  *
2289  * Free all IBI slots allated by a generic IBI pool.
2290  */
2291 void i3c_generic_ibi_free_pool(struct i3c_generic_ibi_pool *pool)
2292 {
2293 	struct i3c_generic_ibi_slot *slot;
2294 	unsigned int nslots = 0;
2295 
2296 	while (!list_empty(&pool->free_slots)) {
2297 		slot = list_first_entry(&pool->free_slots,
2298 					struct i3c_generic_ibi_slot, node);
2299 		list_del(&slot->node);
2300 		nslots++;
2301 	}
2302 
2303 	/*
2304 	 * If the number of freed slots is not equal to the number of allocated
2305 	 * slots we have a leak somewhere.
2306 	 */
2307 	WARN_ON(nslots != pool->num_slots);
2308 
2309 	kfree(pool->payload_buf);
2310 	kfree(pool->slots);
2311 	kfree(pool);
2312 }
2313 EXPORT_SYMBOL_GPL(i3c_generic_ibi_free_pool);
2314 
2315 /**
2316  * i3c_generic_ibi_alloc_pool() - Create a generic IBI pool
2317  * @dev: the device this pool will be used for
2318  * @req: IBI setup request describing what the device driver expects
2319  *
2320  * Create a generic IBI pool based on the information provided in @req.
2321  *
2322  * Return: a valid IBI pool in case of success, an ERR_PTR() otherwise.
2323  */
2324 struct i3c_generic_ibi_pool *
2325 i3c_generic_ibi_alloc_pool(struct i3c_dev_desc *dev,
2326 			   const struct i3c_ibi_setup *req)
2327 {
2328 	struct i3c_generic_ibi_pool *pool;
2329 	struct i3c_generic_ibi_slot *slot;
2330 	unsigned int i;
2331 	int ret;
2332 
2333 	pool = kzalloc(sizeof(*pool), GFP_KERNEL);
2334 	if (!pool)
2335 		return ERR_PTR(-ENOMEM);
2336 
2337 	spin_lock_init(&pool->lock);
2338 	INIT_LIST_HEAD(&pool->free_slots);
2339 	INIT_LIST_HEAD(&pool->pending);
2340 
2341 	pool->slots = kcalloc(req->num_slots, sizeof(*slot), GFP_KERNEL);
2342 	if (!pool->slots) {
2343 		ret = -ENOMEM;
2344 		goto err_free_pool;
2345 	}
2346 
2347 	if (req->max_payload_len) {
2348 		pool->payload_buf = kcalloc(req->num_slots,
2349 					    req->max_payload_len, GFP_KERNEL);
2350 		if (!pool->payload_buf) {
2351 			ret = -ENOMEM;
2352 			goto err_free_pool;
2353 		}
2354 	}
2355 
2356 	for (i = 0; i < req->num_slots; i++) {
2357 		slot = &pool->slots[i];
2358 		i3c_master_init_ibi_slot(dev, &slot->base);
2359 
2360 		if (req->max_payload_len)
2361 			slot->base.data = pool->payload_buf +
2362 					  (i * req->max_payload_len);
2363 
2364 		list_add_tail(&slot->node, &pool->free_slots);
2365 		pool->num_slots++;
2366 	}
2367 
2368 	return pool;
2369 
2370 err_free_pool:
2371 	i3c_generic_ibi_free_pool(pool);
2372 	return ERR_PTR(ret);
2373 }
2374 EXPORT_SYMBOL_GPL(i3c_generic_ibi_alloc_pool);
2375 
2376 /**
2377  * i3c_generic_ibi_get_free_slot() - Get a free slot from a generic IBI pool
2378  * @pool: the pool to query an IBI slot on
2379  *
2380  * Search for a free slot in a generic IBI pool.
2381  * The slot should be returned to the pool using i3c_generic_ibi_recycle_slot()
2382  * when it's no longer needed.
2383  *
2384  * Return: a pointer to a free slot, or NULL if there's no free slot available.
2385  */
2386 struct i3c_ibi_slot *
2387 i3c_generic_ibi_get_free_slot(struct i3c_generic_ibi_pool *pool)
2388 {
2389 	struct i3c_generic_ibi_slot *slot;
2390 	unsigned long flags;
2391 
2392 	spin_lock_irqsave(&pool->lock, flags);
2393 	slot = list_first_entry_or_null(&pool->free_slots,
2394 					struct i3c_generic_ibi_slot, node);
2395 	if (slot)
2396 		list_del(&slot->node);
2397 	spin_unlock_irqrestore(&pool->lock, flags);
2398 
2399 	return slot ? &slot->base : NULL;
2400 }
2401 EXPORT_SYMBOL_GPL(i3c_generic_ibi_get_free_slot);
2402 
2403 /**
2404  * i3c_generic_ibi_recycle_slot() - Return a slot to a generic IBI pool
2405  * @pool: the pool to return the IBI slot to
2406  * @s: IBI slot to recycle
2407  *
2408  * Add an IBI slot back to its generic IBI pool. Should be called from the
2409  * master driver struct_master_controller_ops->recycle_ibi() method.
2410  */
2411 void i3c_generic_ibi_recycle_slot(struct i3c_generic_ibi_pool *pool,
2412 				  struct i3c_ibi_slot *s)
2413 {
2414 	struct i3c_generic_ibi_slot *slot;
2415 	unsigned long flags;
2416 
2417 	if (!s)
2418 		return;
2419 
2420 	slot = container_of(s, struct i3c_generic_ibi_slot, base);
2421 	spin_lock_irqsave(&pool->lock, flags);
2422 	list_add_tail(&slot->node, &pool->free_slots);
2423 	spin_unlock_irqrestore(&pool->lock, flags);
2424 }
2425 EXPORT_SYMBOL_GPL(i3c_generic_ibi_recycle_slot);
2426 
2427 static int i3c_master_check_ops(const struct i3c_master_controller_ops *ops)
2428 {
2429 	if (!ops || !ops->bus_init || !ops->priv_xfers ||
2430 	    !ops->send_ccc_cmd || !ops->do_daa || !ops->i2c_xfers)
2431 		return -EINVAL;
2432 
2433 	if (ops->request_ibi &&
2434 	    (!ops->enable_ibi || !ops->disable_ibi || !ops->free_ibi ||
2435 	     !ops->recycle_ibi_slot))
2436 		return -EINVAL;
2437 
2438 	return 0;
2439 }
2440 
2441 /**
2442  * i3c_master_register() - register an I3C master
2443  * @master: master used to send frames on the bus
2444  * @parent: the parent device (the one that provides this I3C master
2445  *	    controller)
2446  * @ops: the master controller operations
2447  * @secondary: true if you are registering a secondary master. Will return
2448  *	       -ENOTSUPP if set to true since secondary masters are not yet
2449  *	       supported
2450  *
2451  * This function takes care of everything for you:
2452  *
2453  * - creates and initializes the I3C bus
2454  * - populates the bus with static I2C devs if @parent->of_node is not
2455  *   NULL
2456  * - registers all I3C devices added by the controller during bus
2457  *   initialization
2458  * - registers the I2C adapter and all I2C devices
2459  *
2460  * Return: 0 in case of success, a negative error code otherwise.
2461  */
2462 int i3c_master_register(struct i3c_master_controller *master,
2463 			struct device *parent,
2464 			const struct i3c_master_controller_ops *ops,
2465 			bool secondary)
2466 {
2467 	unsigned long i2c_scl_rate = I3C_BUS_I2C_FM_PLUS_SCL_RATE;
2468 	struct i3c_bus *i3cbus = i3c_master_get_bus(master);
2469 	enum i3c_bus_mode mode = I3C_BUS_MODE_PURE;
2470 	struct i2c_dev_boardinfo *i2cbi;
2471 	int ret;
2472 
2473 	/* We do not support secondary masters yet. */
2474 	if (secondary)
2475 		return -ENOTSUPP;
2476 
2477 	ret = i3c_master_check_ops(ops);
2478 	if (ret)
2479 		return ret;
2480 
2481 	master->dev.parent = parent;
2482 	master->dev.of_node = of_node_get(parent->of_node);
2483 	master->dev.bus = &i3c_bus_type;
2484 	master->dev.type = &i3c_masterdev_type;
2485 	master->dev.release = i3c_masterdev_release;
2486 	master->ops = ops;
2487 	master->secondary = secondary;
2488 	INIT_LIST_HEAD(&master->boardinfo.i2c);
2489 	INIT_LIST_HEAD(&master->boardinfo.i3c);
2490 
2491 	ret = i3c_bus_init(i3cbus);
2492 	if (ret)
2493 		return ret;
2494 
2495 	device_initialize(&master->dev);
2496 	dev_set_name(&master->dev, "i3c-%d", i3cbus->id);
2497 
2498 	ret = of_populate_i3c_bus(master);
2499 	if (ret)
2500 		goto err_put_dev;
2501 
2502 	list_for_each_entry(i2cbi, &master->boardinfo.i2c, node) {
2503 		switch (i2cbi->lvr & I3C_LVR_I2C_INDEX_MASK) {
2504 		case I3C_LVR_I2C_INDEX(0):
2505 			if (mode < I3C_BUS_MODE_MIXED_FAST)
2506 				mode = I3C_BUS_MODE_MIXED_FAST;
2507 			break;
2508 		case I3C_LVR_I2C_INDEX(1):
2509 			if (mode < I3C_BUS_MODE_MIXED_LIMITED)
2510 				mode = I3C_BUS_MODE_MIXED_LIMITED;
2511 			break;
2512 		case I3C_LVR_I2C_INDEX(2):
2513 			if (mode < I3C_BUS_MODE_MIXED_SLOW)
2514 				mode = I3C_BUS_MODE_MIXED_SLOW;
2515 			break;
2516 		default:
2517 			ret = -EINVAL;
2518 			goto err_put_dev;
2519 		}
2520 
2521 		if (i2cbi->lvr & I3C_LVR_I2C_FM_MODE)
2522 			i2c_scl_rate = I3C_BUS_I2C_FM_SCL_RATE;
2523 	}
2524 
2525 	ret = i3c_bus_set_mode(i3cbus, mode, i2c_scl_rate);
2526 	if (ret)
2527 		goto err_put_dev;
2528 
2529 	master->wq = alloc_workqueue("%s", 0, 0, dev_name(parent));
2530 	if (!master->wq) {
2531 		ret = -ENOMEM;
2532 		goto err_put_dev;
2533 	}
2534 
2535 	ret = i3c_master_bus_init(master);
2536 	if (ret)
2537 		goto err_put_dev;
2538 
2539 	ret = device_add(&master->dev);
2540 	if (ret)
2541 		goto err_cleanup_bus;
2542 
2543 	/*
2544 	 * Expose our I3C bus as an I2C adapter so that I2C devices are exposed
2545 	 * through the I2C subsystem.
2546 	 */
2547 	ret = i3c_master_i2c_adapter_init(master);
2548 	if (ret)
2549 		goto err_del_dev;
2550 
2551 	/*
2552 	 * We're done initializing the bus and the controller, we can now
2553 	 * register I3C devices discovered during the initial DAA.
2554 	 */
2555 	master->init_done = true;
2556 	i3c_bus_normaluse_lock(&master->bus);
2557 	i3c_master_register_new_i3c_devs(master);
2558 	i3c_bus_normaluse_unlock(&master->bus);
2559 
2560 	return 0;
2561 
2562 err_del_dev:
2563 	device_del(&master->dev);
2564 
2565 err_cleanup_bus:
2566 	i3c_master_bus_cleanup(master);
2567 
2568 err_put_dev:
2569 	put_device(&master->dev);
2570 
2571 	return ret;
2572 }
2573 EXPORT_SYMBOL_GPL(i3c_master_register);
2574 
2575 /**
2576  * i3c_master_unregister() - unregister an I3C master
2577  * @master: master used to send frames on the bus
2578  *
2579  * Basically undo everything done in i3c_master_register().
2580  *
2581  * Return: 0 in case of success, a negative error code otherwise.
2582  */
2583 int i3c_master_unregister(struct i3c_master_controller *master)
2584 {
2585 	i3c_master_i2c_adapter_cleanup(master);
2586 	i3c_master_unregister_i3c_devs(master);
2587 	i3c_master_bus_cleanup(master);
2588 	device_unregister(&master->dev);
2589 
2590 	return 0;
2591 }
2592 EXPORT_SYMBOL_GPL(i3c_master_unregister);
2593 
2594 int i3c_dev_do_priv_xfers_locked(struct i3c_dev_desc *dev,
2595 				 struct i3c_priv_xfer *xfers,
2596 				 int nxfers)
2597 {
2598 	struct i3c_master_controller *master;
2599 
2600 	if (!dev)
2601 		return -ENOENT;
2602 
2603 	master = i3c_dev_get_master(dev);
2604 	if (!master || !xfers)
2605 		return -EINVAL;
2606 
2607 	if (!master->ops->priv_xfers)
2608 		return -ENOTSUPP;
2609 
2610 	return master->ops->priv_xfers(dev, xfers, nxfers);
2611 }
2612 
2613 int i3c_dev_disable_ibi_locked(struct i3c_dev_desc *dev)
2614 {
2615 	struct i3c_master_controller *master;
2616 	int ret;
2617 
2618 	if (!dev->ibi)
2619 		return -EINVAL;
2620 
2621 	master = i3c_dev_get_master(dev);
2622 	ret = master->ops->disable_ibi(dev);
2623 	if (ret)
2624 		return ret;
2625 
2626 	reinit_completion(&dev->ibi->all_ibis_handled);
2627 	if (atomic_read(&dev->ibi->pending_ibis))
2628 		wait_for_completion(&dev->ibi->all_ibis_handled);
2629 
2630 	dev->ibi->enabled = false;
2631 
2632 	return 0;
2633 }
2634 
2635 int i3c_dev_enable_ibi_locked(struct i3c_dev_desc *dev)
2636 {
2637 	struct i3c_master_controller *master = i3c_dev_get_master(dev);
2638 	int ret;
2639 
2640 	if (!dev->ibi)
2641 		return -EINVAL;
2642 
2643 	ret = master->ops->enable_ibi(dev);
2644 	if (!ret)
2645 		dev->ibi->enabled = true;
2646 
2647 	return ret;
2648 }
2649 
2650 int i3c_dev_request_ibi_locked(struct i3c_dev_desc *dev,
2651 			       const struct i3c_ibi_setup *req)
2652 {
2653 	struct i3c_master_controller *master = i3c_dev_get_master(dev);
2654 	struct i3c_device_ibi_info *ibi;
2655 	int ret;
2656 
2657 	if (!master->ops->request_ibi)
2658 		return -ENOTSUPP;
2659 
2660 	if (dev->ibi)
2661 		return -EBUSY;
2662 
2663 	ibi = kzalloc(sizeof(*ibi), GFP_KERNEL);
2664 	if (!ibi)
2665 		return -ENOMEM;
2666 
2667 	atomic_set(&ibi->pending_ibis, 0);
2668 	init_completion(&ibi->all_ibis_handled);
2669 	ibi->handler = req->handler;
2670 	ibi->max_payload_len = req->max_payload_len;
2671 	ibi->num_slots = req->num_slots;
2672 
2673 	dev->ibi = ibi;
2674 	ret = master->ops->request_ibi(dev, req);
2675 	if (ret) {
2676 		kfree(ibi);
2677 		dev->ibi = NULL;
2678 	}
2679 
2680 	return ret;
2681 }
2682 
2683 void i3c_dev_free_ibi_locked(struct i3c_dev_desc *dev)
2684 {
2685 	struct i3c_master_controller *master = i3c_dev_get_master(dev);
2686 
2687 	if (!dev->ibi)
2688 		return;
2689 
2690 	if (WARN_ON(dev->ibi->enabled))
2691 		WARN_ON(i3c_dev_disable_ibi_locked(dev));
2692 
2693 	master->ops->free_ibi(dev);
2694 	kfree(dev->ibi);
2695 	dev->ibi = NULL;
2696 }
2697 
2698 static int __init i3c_init(void)
2699 {
2700 	return bus_register(&i3c_bus_type);
2701 }
2702 subsys_initcall(i3c_init);
2703 
2704 static void __exit i3c_exit(void)
2705 {
2706 	idr_destroy(&i3c_bus_idr);
2707 	bus_unregister(&i3c_bus_type);
2708 }
2709 module_exit(i3c_exit);
2710 
2711 MODULE_AUTHOR("Boris Brezillon <boris.brezillon@bootlin.com>");
2712 MODULE_DESCRIPTION("I3C core");
2713 MODULE_LICENSE("GPL v2");
2714