xref: /openbmc/linux/drivers/i3c/master.c (revision 62eab49f)
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 int 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 	return 0;
336 }
337 
338 struct bus_type i3c_bus_type = {
339 	.name = "i3c",
340 	.match = i3c_device_match,
341 	.probe = i3c_device_probe,
342 	.remove = i3c_device_remove,
343 };
344 
345 static enum i3c_addr_slot_status
346 i3c_bus_get_addr_slot_status(struct i3c_bus *bus, u16 addr)
347 {
348 	int status, bitpos = addr * 2;
349 
350 	if (addr > I2C_MAX_ADDR)
351 		return I3C_ADDR_SLOT_RSVD;
352 
353 	status = bus->addrslots[bitpos / BITS_PER_LONG];
354 	status >>= bitpos % BITS_PER_LONG;
355 
356 	return status & I3C_ADDR_SLOT_STATUS_MASK;
357 }
358 
359 static void i3c_bus_set_addr_slot_status(struct i3c_bus *bus, u16 addr,
360 					 enum i3c_addr_slot_status status)
361 {
362 	int bitpos = addr * 2;
363 	unsigned long *ptr;
364 
365 	if (addr > I2C_MAX_ADDR)
366 		return;
367 
368 	ptr = bus->addrslots + (bitpos / BITS_PER_LONG);
369 	*ptr &= ~((unsigned long)I3C_ADDR_SLOT_STATUS_MASK <<
370 						(bitpos % BITS_PER_LONG));
371 	*ptr |= (unsigned long)status << (bitpos % BITS_PER_LONG);
372 }
373 
374 static bool i3c_bus_dev_addr_is_avail(struct i3c_bus *bus, u8 addr)
375 {
376 	enum i3c_addr_slot_status status;
377 
378 	status = i3c_bus_get_addr_slot_status(bus, addr);
379 
380 	return status == I3C_ADDR_SLOT_FREE;
381 }
382 
383 static int i3c_bus_get_free_addr(struct i3c_bus *bus, u8 start_addr)
384 {
385 	enum i3c_addr_slot_status status;
386 	u8 addr;
387 
388 	for (addr = start_addr; addr < I3C_MAX_ADDR; addr++) {
389 		status = i3c_bus_get_addr_slot_status(bus, addr);
390 		if (status == I3C_ADDR_SLOT_FREE)
391 			return addr;
392 	}
393 
394 	return -ENOMEM;
395 }
396 
397 static void i3c_bus_init_addrslots(struct i3c_bus *bus)
398 {
399 	int i;
400 
401 	/* Addresses 0 to 7 are reserved. */
402 	for (i = 0; i < 8; i++)
403 		i3c_bus_set_addr_slot_status(bus, i, I3C_ADDR_SLOT_RSVD);
404 
405 	/*
406 	 * Reserve broadcast address and all addresses that might collide
407 	 * with the broadcast address when facing a single bit error.
408 	 */
409 	i3c_bus_set_addr_slot_status(bus, I3C_BROADCAST_ADDR,
410 				     I3C_ADDR_SLOT_RSVD);
411 	for (i = 0; i < 7; i++)
412 		i3c_bus_set_addr_slot_status(bus, I3C_BROADCAST_ADDR ^ BIT(i),
413 					     I3C_ADDR_SLOT_RSVD);
414 }
415 
416 static void i3c_bus_cleanup(struct i3c_bus *i3cbus)
417 {
418 	mutex_lock(&i3c_core_lock);
419 	idr_remove(&i3c_bus_idr, i3cbus->id);
420 	mutex_unlock(&i3c_core_lock);
421 }
422 
423 static int i3c_bus_init(struct i3c_bus *i3cbus)
424 {
425 	int ret;
426 
427 	init_rwsem(&i3cbus->lock);
428 	INIT_LIST_HEAD(&i3cbus->devs.i2c);
429 	INIT_LIST_HEAD(&i3cbus->devs.i3c);
430 	i3c_bus_init_addrslots(i3cbus);
431 	i3cbus->mode = I3C_BUS_MODE_PURE;
432 
433 	mutex_lock(&i3c_core_lock);
434 	ret = idr_alloc(&i3c_bus_idr, i3cbus, 0, 0, GFP_KERNEL);
435 	mutex_unlock(&i3c_core_lock);
436 
437 	if (ret < 0)
438 		return ret;
439 
440 	i3cbus->id = ret;
441 
442 	return 0;
443 }
444 
445 static const char * const i3c_bus_mode_strings[] = {
446 	[I3C_BUS_MODE_PURE] = "pure",
447 	[I3C_BUS_MODE_MIXED_FAST] = "mixed-fast",
448 	[I3C_BUS_MODE_MIXED_LIMITED] = "mixed-limited",
449 	[I3C_BUS_MODE_MIXED_SLOW] = "mixed-slow",
450 };
451 
452 static ssize_t mode_show(struct device *dev,
453 			 struct device_attribute *da,
454 			 char *buf)
455 {
456 	struct i3c_bus *i3cbus = dev_to_i3cbus(dev);
457 	ssize_t ret;
458 
459 	i3c_bus_normaluse_lock(i3cbus);
460 	if (i3cbus->mode < 0 ||
461 	    i3cbus->mode >= ARRAY_SIZE(i3c_bus_mode_strings) ||
462 	    !i3c_bus_mode_strings[i3cbus->mode])
463 		ret = sprintf(buf, "unknown\n");
464 	else
465 		ret = sprintf(buf, "%s\n", i3c_bus_mode_strings[i3cbus->mode]);
466 	i3c_bus_normaluse_unlock(i3cbus);
467 
468 	return ret;
469 }
470 static DEVICE_ATTR_RO(mode);
471 
472 static ssize_t current_master_show(struct device *dev,
473 				   struct device_attribute *da,
474 				   char *buf)
475 {
476 	struct i3c_bus *i3cbus = dev_to_i3cbus(dev);
477 	ssize_t ret;
478 
479 	i3c_bus_normaluse_lock(i3cbus);
480 	ret = sprintf(buf, "%d-%llx\n", i3cbus->id,
481 		      i3cbus->cur_master->info.pid);
482 	i3c_bus_normaluse_unlock(i3cbus);
483 
484 	return ret;
485 }
486 static DEVICE_ATTR_RO(current_master);
487 
488 static ssize_t i3c_scl_frequency_show(struct device *dev,
489 				      struct device_attribute *da,
490 				      char *buf)
491 {
492 	struct i3c_bus *i3cbus = dev_to_i3cbus(dev);
493 	ssize_t ret;
494 
495 	i3c_bus_normaluse_lock(i3cbus);
496 	ret = sprintf(buf, "%ld\n", i3cbus->scl_rate.i3c);
497 	i3c_bus_normaluse_unlock(i3cbus);
498 
499 	return ret;
500 }
501 static DEVICE_ATTR_RO(i3c_scl_frequency);
502 
503 static ssize_t i2c_scl_frequency_show(struct device *dev,
504 				      struct device_attribute *da,
505 				      char *buf)
506 {
507 	struct i3c_bus *i3cbus = dev_to_i3cbus(dev);
508 	ssize_t ret;
509 
510 	i3c_bus_normaluse_lock(i3cbus);
511 	ret = sprintf(buf, "%ld\n", i3cbus->scl_rate.i2c);
512 	i3c_bus_normaluse_unlock(i3cbus);
513 
514 	return ret;
515 }
516 static DEVICE_ATTR_RO(i2c_scl_frequency);
517 
518 static struct attribute *i3c_masterdev_attrs[] = {
519 	&dev_attr_mode.attr,
520 	&dev_attr_current_master.attr,
521 	&dev_attr_i3c_scl_frequency.attr,
522 	&dev_attr_i2c_scl_frequency.attr,
523 	&dev_attr_bcr.attr,
524 	&dev_attr_dcr.attr,
525 	&dev_attr_pid.attr,
526 	&dev_attr_dynamic_address.attr,
527 	&dev_attr_hdrcap.attr,
528 	NULL,
529 };
530 ATTRIBUTE_GROUPS(i3c_masterdev);
531 
532 static void i3c_masterdev_release(struct device *dev)
533 {
534 	struct i3c_master_controller *master = dev_to_i3cmaster(dev);
535 	struct i3c_bus *bus = dev_to_i3cbus(dev);
536 
537 	if (master->wq)
538 		destroy_workqueue(master->wq);
539 
540 	WARN_ON(!list_empty(&bus->devs.i2c) || !list_empty(&bus->devs.i3c));
541 	i3c_bus_cleanup(bus);
542 
543 	of_node_put(dev->of_node);
544 }
545 
546 static const struct device_type i3c_masterdev_type = {
547 	.groups	= i3c_masterdev_groups,
548 };
549 
550 static int i3c_bus_set_mode(struct i3c_bus *i3cbus, enum i3c_bus_mode mode,
551 			    unsigned long max_i2c_scl_rate)
552 {
553 	struct i3c_master_controller *master = i3c_bus_to_i3c_master(i3cbus);
554 
555 	i3cbus->mode = mode;
556 
557 	switch (i3cbus->mode) {
558 	case I3C_BUS_MODE_PURE:
559 		if (!i3cbus->scl_rate.i3c)
560 			i3cbus->scl_rate.i3c = I3C_BUS_TYP_I3C_SCL_RATE;
561 		break;
562 	case I3C_BUS_MODE_MIXED_FAST:
563 	case I3C_BUS_MODE_MIXED_LIMITED:
564 		if (!i3cbus->scl_rate.i3c)
565 			i3cbus->scl_rate.i3c = I3C_BUS_TYP_I3C_SCL_RATE;
566 		if (!i3cbus->scl_rate.i2c)
567 			i3cbus->scl_rate.i2c = max_i2c_scl_rate;
568 		break;
569 	case I3C_BUS_MODE_MIXED_SLOW:
570 		if (!i3cbus->scl_rate.i2c)
571 			i3cbus->scl_rate.i2c = max_i2c_scl_rate;
572 		if (!i3cbus->scl_rate.i3c ||
573 		    i3cbus->scl_rate.i3c > i3cbus->scl_rate.i2c)
574 			i3cbus->scl_rate.i3c = i3cbus->scl_rate.i2c;
575 		break;
576 	default:
577 		return -EINVAL;
578 	}
579 
580 	dev_dbg(&master->dev, "i2c-scl = %ld Hz i3c-scl = %ld Hz\n",
581 		i3cbus->scl_rate.i2c, i3cbus->scl_rate.i3c);
582 
583 	/*
584 	 * I3C/I2C frequency may have been overridden, check that user-provided
585 	 * values are not exceeding max possible frequency.
586 	 */
587 	if (i3cbus->scl_rate.i3c > I3C_BUS_MAX_I3C_SCL_RATE ||
588 	    i3cbus->scl_rate.i2c > I3C_BUS_I2C_FM_PLUS_SCL_RATE)
589 		return -EINVAL;
590 
591 	return 0;
592 }
593 
594 static struct i3c_master_controller *
595 i2c_adapter_to_i3c_master(struct i2c_adapter *adap)
596 {
597 	return container_of(adap, struct i3c_master_controller, i2c);
598 }
599 
600 static struct i2c_adapter *
601 i3c_master_to_i2c_adapter(struct i3c_master_controller *master)
602 {
603 	return &master->i2c;
604 }
605 
606 static void i3c_master_free_i2c_dev(struct i2c_dev_desc *dev)
607 {
608 	kfree(dev);
609 }
610 
611 static struct i2c_dev_desc *
612 i3c_master_alloc_i2c_dev(struct i3c_master_controller *master,
613 			 const struct i2c_dev_boardinfo *boardinfo)
614 {
615 	struct i2c_dev_desc *dev;
616 
617 	dev = kzalloc(sizeof(*dev), GFP_KERNEL);
618 	if (!dev)
619 		return ERR_PTR(-ENOMEM);
620 
621 	dev->common.master = master;
622 	dev->boardinfo = boardinfo;
623 	dev->addr = boardinfo->base.addr;
624 	dev->lvr = boardinfo->lvr;
625 
626 	return dev;
627 }
628 
629 static void *i3c_ccc_cmd_dest_init(struct i3c_ccc_cmd_dest *dest, u8 addr,
630 				   u16 payloadlen)
631 {
632 	dest->addr = addr;
633 	dest->payload.len = payloadlen;
634 	if (payloadlen)
635 		dest->payload.data = kzalloc(payloadlen, GFP_KERNEL);
636 	else
637 		dest->payload.data = NULL;
638 
639 	return dest->payload.data;
640 }
641 
642 static void i3c_ccc_cmd_dest_cleanup(struct i3c_ccc_cmd_dest *dest)
643 {
644 	kfree(dest->payload.data);
645 }
646 
647 static void i3c_ccc_cmd_init(struct i3c_ccc_cmd *cmd, bool rnw, u8 id,
648 			     struct i3c_ccc_cmd_dest *dests,
649 			     unsigned int ndests)
650 {
651 	cmd->rnw = rnw ? 1 : 0;
652 	cmd->id = id;
653 	cmd->dests = dests;
654 	cmd->ndests = ndests;
655 	cmd->err = I3C_ERROR_UNKNOWN;
656 }
657 
658 static int i3c_master_send_ccc_cmd_locked(struct i3c_master_controller *master,
659 					  struct i3c_ccc_cmd *cmd)
660 {
661 	int ret;
662 
663 	if (!cmd || !master)
664 		return -EINVAL;
665 
666 	if (WARN_ON(master->init_done &&
667 		    !rwsem_is_locked(&master->bus.lock)))
668 		return -EINVAL;
669 
670 	if (!master->ops->send_ccc_cmd)
671 		return -ENOTSUPP;
672 
673 	if ((cmd->id & I3C_CCC_DIRECT) && (!cmd->dests || !cmd->ndests))
674 		return -EINVAL;
675 
676 	if (master->ops->supports_ccc_cmd &&
677 	    !master->ops->supports_ccc_cmd(master, cmd))
678 		return -ENOTSUPP;
679 
680 	ret = master->ops->send_ccc_cmd(master, cmd);
681 	if (ret) {
682 		if (cmd->err != I3C_ERROR_UNKNOWN)
683 			return cmd->err;
684 
685 		return ret;
686 	}
687 
688 	return 0;
689 }
690 
691 static struct i2c_dev_desc *
692 i3c_master_find_i2c_dev_by_addr(const struct i3c_master_controller *master,
693 				u16 addr)
694 {
695 	struct i2c_dev_desc *dev;
696 
697 	i3c_bus_for_each_i2cdev(&master->bus, dev) {
698 		if (dev->boardinfo->base.addr == addr)
699 			return dev;
700 	}
701 
702 	return NULL;
703 }
704 
705 /**
706  * i3c_master_get_free_addr() - get a free address on the bus
707  * @master: I3C master object
708  * @start_addr: where to start searching
709  *
710  * This function must be called with the bus lock held in write mode.
711  *
712  * Return: the first free address starting at @start_addr (included) or -ENOMEM
713  * if there's no more address available.
714  */
715 int i3c_master_get_free_addr(struct i3c_master_controller *master,
716 			     u8 start_addr)
717 {
718 	return i3c_bus_get_free_addr(&master->bus, start_addr);
719 }
720 EXPORT_SYMBOL_GPL(i3c_master_get_free_addr);
721 
722 static void i3c_device_release(struct device *dev)
723 {
724 	struct i3c_device *i3cdev = dev_to_i3cdev(dev);
725 
726 	WARN_ON(i3cdev->desc);
727 
728 	of_node_put(i3cdev->dev.of_node);
729 	kfree(i3cdev);
730 }
731 
732 static void i3c_master_free_i3c_dev(struct i3c_dev_desc *dev)
733 {
734 	kfree(dev);
735 }
736 
737 static struct i3c_dev_desc *
738 i3c_master_alloc_i3c_dev(struct i3c_master_controller *master,
739 			 const struct i3c_device_info *info)
740 {
741 	struct i3c_dev_desc *dev;
742 
743 	dev = kzalloc(sizeof(*dev), GFP_KERNEL);
744 	if (!dev)
745 		return ERR_PTR(-ENOMEM);
746 
747 	dev->common.master = master;
748 	dev->info = *info;
749 	mutex_init(&dev->ibi_lock);
750 
751 	return dev;
752 }
753 
754 static int i3c_master_rstdaa_locked(struct i3c_master_controller *master,
755 				    u8 addr)
756 {
757 	enum i3c_addr_slot_status addrstat;
758 	struct i3c_ccc_cmd_dest dest;
759 	struct i3c_ccc_cmd cmd;
760 	int ret;
761 
762 	if (!master)
763 		return -EINVAL;
764 
765 	addrstat = i3c_bus_get_addr_slot_status(&master->bus, addr);
766 	if (addr != I3C_BROADCAST_ADDR && addrstat != I3C_ADDR_SLOT_I3C_DEV)
767 		return -EINVAL;
768 
769 	i3c_ccc_cmd_dest_init(&dest, addr, 0);
770 	i3c_ccc_cmd_init(&cmd, false,
771 			 I3C_CCC_RSTDAA(addr == I3C_BROADCAST_ADDR),
772 			 &dest, 1);
773 	ret = i3c_master_send_ccc_cmd_locked(master, &cmd);
774 	i3c_ccc_cmd_dest_cleanup(&dest);
775 
776 	return ret;
777 }
778 
779 /**
780  * i3c_master_entdaa_locked() - start a DAA (Dynamic Address Assignment)
781  *				procedure
782  * @master: master used to send frames on the bus
783  *
784  * Send a ENTDAA CCC command to start a DAA procedure.
785  *
786  * Note that this function only sends the ENTDAA CCC command, all the logic
787  * behind dynamic address assignment has to be handled in the I3C master
788  * driver.
789  *
790  * This function must be called with the bus lock held in write mode.
791  *
792  * Return: 0 in case of success, a positive I3C error code if the error is
793  * one of the official Mx error codes, and a negative error code otherwise.
794  */
795 int i3c_master_entdaa_locked(struct i3c_master_controller *master)
796 {
797 	struct i3c_ccc_cmd_dest dest;
798 	struct i3c_ccc_cmd cmd;
799 	int ret;
800 
801 	i3c_ccc_cmd_dest_init(&dest, I3C_BROADCAST_ADDR, 0);
802 	i3c_ccc_cmd_init(&cmd, false, I3C_CCC_ENTDAA, &dest, 1);
803 	ret = i3c_master_send_ccc_cmd_locked(master, &cmd);
804 	i3c_ccc_cmd_dest_cleanup(&dest);
805 
806 	return ret;
807 }
808 EXPORT_SYMBOL_GPL(i3c_master_entdaa_locked);
809 
810 static int i3c_master_enec_disec_locked(struct i3c_master_controller *master,
811 					u8 addr, bool enable, u8 evts)
812 {
813 	struct i3c_ccc_events *events;
814 	struct i3c_ccc_cmd_dest dest;
815 	struct i3c_ccc_cmd cmd;
816 	int ret;
817 
818 	events = i3c_ccc_cmd_dest_init(&dest, addr, sizeof(*events));
819 	if (!events)
820 		return -ENOMEM;
821 
822 	events->events = evts;
823 	i3c_ccc_cmd_init(&cmd, false,
824 			 enable ?
825 			 I3C_CCC_ENEC(addr == I3C_BROADCAST_ADDR) :
826 			 I3C_CCC_DISEC(addr == I3C_BROADCAST_ADDR),
827 			 &dest, 1);
828 	ret = i3c_master_send_ccc_cmd_locked(master, &cmd);
829 	i3c_ccc_cmd_dest_cleanup(&dest);
830 
831 	return ret;
832 }
833 
834 /**
835  * i3c_master_disec_locked() - send a DISEC CCC command
836  * @master: master used to send frames on the bus
837  * @addr: a valid I3C slave address or %I3C_BROADCAST_ADDR
838  * @evts: events to disable
839  *
840  * Send a DISEC CCC command to disable some or all events coming from a
841  * specific slave, or all devices if @addr is %I3C_BROADCAST_ADDR.
842  *
843  * This function must be called with the bus lock held in write mode.
844  *
845  * Return: 0 in case of success, a positive I3C error code if the error is
846  * one of the official Mx error codes, and a negative error code otherwise.
847  */
848 int i3c_master_disec_locked(struct i3c_master_controller *master, u8 addr,
849 			    u8 evts)
850 {
851 	return i3c_master_enec_disec_locked(master, addr, false, evts);
852 }
853 EXPORT_SYMBOL_GPL(i3c_master_disec_locked);
854 
855 /**
856  * i3c_master_enec_locked() - send an ENEC CCC command
857  * @master: master used to send frames on the bus
858  * @addr: a valid I3C slave address or %I3C_BROADCAST_ADDR
859  * @evts: events to disable
860  *
861  * Sends an ENEC CCC command to enable some or all events coming from a
862  * specific slave, or all devices if @addr is %I3C_BROADCAST_ADDR.
863  *
864  * This function must be called with the bus lock held in write mode.
865  *
866  * Return: 0 in case of success, a positive I3C error code if the error is
867  * one of the official Mx error codes, and a negative error code otherwise.
868  */
869 int i3c_master_enec_locked(struct i3c_master_controller *master, u8 addr,
870 			   u8 evts)
871 {
872 	return i3c_master_enec_disec_locked(master, addr, true, evts);
873 }
874 EXPORT_SYMBOL_GPL(i3c_master_enec_locked);
875 
876 /**
877  * i3c_master_defslvs_locked() - send a DEFSLVS CCC command
878  * @master: master used to send frames on the bus
879  *
880  * Send a DEFSLVS CCC command containing all the devices known to the @master.
881  * This is useful when you have secondary masters on the bus to propagate
882  * device information.
883  *
884  * This should be called after all I3C devices have been discovered (in other
885  * words, after the DAA procedure has finished) and instantiated in
886  * &i3c_master_controller_ops->bus_init().
887  * It should also be called if a master ACKed an Hot-Join request and assigned
888  * a dynamic address to the device joining the bus.
889  *
890  * This function must be called with the bus lock held in write mode.
891  *
892  * Return: 0 in case of success, a positive I3C error code if the error is
893  * one of the official Mx error codes, and a negative error code otherwise.
894  */
895 int i3c_master_defslvs_locked(struct i3c_master_controller *master)
896 {
897 	struct i3c_ccc_defslvs *defslvs;
898 	struct i3c_ccc_dev_desc *desc;
899 	struct i3c_ccc_cmd_dest dest;
900 	struct i3c_dev_desc *i3cdev;
901 	struct i2c_dev_desc *i2cdev;
902 	struct i3c_ccc_cmd cmd;
903 	struct i3c_bus *bus;
904 	bool send = false;
905 	int ndevs = 0, ret;
906 
907 	if (!master)
908 		return -EINVAL;
909 
910 	bus = i3c_master_get_bus(master);
911 	i3c_bus_for_each_i3cdev(bus, i3cdev) {
912 		ndevs++;
913 
914 		if (i3cdev == master->this)
915 			continue;
916 
917 		if (I3C_BCR_DEVICE_ROLE(i3cdev->info.bcr) ==
918 		    I3C_BCR_I3C_MASTER)
919 			send = true;
920 	}
921 
922 	/* No other master on the bus, skip DEFSLVS. */
923 	if (!send)
924 		return 0;
925 
926 	i3c_bus_for_each_i2cdev(bus, i2cdev)
927 		ndevs++;
928 
929 	defslvs = i3c_ccc_cmd_dest_init(&dest, I3C_BROADCAST_ADDR,
930 					struct_size(defslvs, slaves,
931 						    ndevs - 1));
932 	if (!defslvs)
933 		return -ENOMEM;
934 
935 	defslvs->count = ndevs;
936 	defslvs->master.bcr = master->this->info.bcr;
937 	defslvs->master.dcr = master->this->info.dcr;
938 	defslvs->master.dyn_addr = master->this->info.dyn_addr << 1;
939 	defslvs->master.static_addr = I3C_BROADCAST_ADDR << 1;
940 
941 	desc = defslvs->slaves;
942 	i3c_bus_for_each_i2cdev(bus, i2cdev) {
943 		desc->lvr = i2cdev->lvr;
944 		desc->static_addr = i2cdev->addr << 1;
945 		desc++;
946 	}
947 
948 	i3c_bus_for_each_i3cdev(bus, i3cdev) {
949 		/* Skip the I3C dev representing this master. */
950 		if (i3cdev == master->this)
951 			continue;
952 
953 		desc->bcr = i3cdev->info.bcr;
954 		desc->dcr = i3cdev->info.dcr;
955 		desc->dyn_addr = i3cdev->info.dyn_addr << 1;
956 		desc->static_addr = i3cdev->info.static_addr << 1;
957 		desc++;
958 	}
959 
960 	i3c_ccc_cmd_init(&cmd, false, I3C_CCC_DEFSLVS, &dest, 1);
961 	ret = i3c_master_send_ccc_cmd_locked(master, &cmd);
962 	i3c_ccc_cmd_dest_cleanup(&dest);
963 
964 	return ret;
965 }
966 EXPORT_SYMBOL_GPL(i3c_master_defslvs_locked);
967 
968 static int i3c_master_setda_locked(struct i3c_master_controller *master,
969 				   u8 oldaddr, u8 newaddr, bool setdasa)
970 {
971 	struct i3c_ccc_cmd_dest dest;
972 	struct i3c_ccc_setda *setda;
973 	struct i3c_ccc_cmd cmd;
974 	int ret;
975 
976 	if (!oldaddr || !newaddr)
977 		return -EINVAL;
978 
979 	setda = i3c_ccc_cmd_dest_init(&dest, oldaddr, sizeof(*setda));
980 	if (!setda)
981 		return -ENOMEM;
982 
983 	setda->addr = newaddr << 1;
984 	i3c_ccc_cmd_init(&cmd, false,
985 			 setdasa ? I3C_CCC_SETDASA : I3C_CCC_SETNEWDA,
986 			 &dest, 1);
987 	ret = i3c_master_send_ccc_cmd_locked(master, &cmd);
988 	i3c_ccc_cmd_dest_cleanup(&dest);
989 
990 	return ret;
991 }
992 
993 static int i3c_master_setdasa_locked(struct i3c_master_controller *master,
994 				     u8 static_addr, u8 dyn_addr)
995 {
996 	return i3c_master_setda_locked(master, static_addr, dyn_addr, true);
997 }
998 
999 static int i3c_master_setnewda_locked(struct i3c_master_controller *master,
1000 				      u8 oldaddr, u8 newaddr)
1001 {
1002 	return i3c_master_setda_locked(master, oldaddr, newaddr, false);
1003 }
1004 
1005 static int i3c_master_getmrl_locked(struct i3c_master_controller *master,
1006 				    struct i3c_device_info *info)
1007 {
1008 	struct i3c_ccc_cmd_dest dest;
1009 	struct i3c_ccc_mrl *mrl;
1010 	struct i3c_ccc_cmd cmd;
1011 	int ret;
1012 
1013 	mrl = i3c_ccc_cmd_dest_init(&dest, info->dyn_addr, sizeof(*mrl));
1014 	if (!mrl)
1015 		return -ENOMEM;
1016 
1017 	/*
1018 	 * When the device does not have IBI payload GETMRL only returns 2
1019 	 * bytes of data.
1020 	 */
1021 	if (!(info->bcr & I3C_BCR_IBI_PAYLOAD))
1022 		dest.payload.len -= 1;
1023 
1024 	i3c_ccc_cmd_init(&cmd, true, I3C_CCC_GETMRL, &dest, 1);
1025 	ret = i3c_master_send_ccc_cmd_locked(master, &cmd);
1026 	if (ret)
1027 		goto out;
1028 
1029 	switch (dest.payload.len) {
1030 	case 3:
1031 		info->max_ibi_len = mrl->ibi_len;
1032 		fallthrough;
1033 	case 2:
1034 		info->max_read_len = be16_to_cpu(mrl->read_len);
1035 		break;
1036 	default:
1037 		ret = -EIO;
1038 		goto out;
1039 	}
1040 
1041 out:
1042 	i3c_ccc_cmd_dest_cleanup(&dest);
1043 
1044 	return ret;
1045 }
1046 
1047 static int i3c_master_getmwl_locked(struct i3c_master_controller *master,
1048 				    struct i3c_device_info *info)
1049 {
1050 	struct i3c_ccc_cmd_dest dest;
1051 	struct i3c_ccc_mwl *mwl;
1052 	struct i3c_ccc_cmd cmd;
1053 	int ret;
1054 
1055 	mwl = i3c_ccc_cmd_dest_init(&dest, info->dyn_addr, sizeof(*mwl));
1056 	if (!mwl)
1057 		return -ENOMEM;
1058 
1059 	i3c_ccc_cmd_init(&cmd, true, I3C_CCC_GETMWL, &dest, 1);
1060 	ret = i3c_master_send_ccc_cmd_locked(master, &cmd);
1061 	if (ret)
1062 		goto out;
1063 
1064 	if (dest.payload.len != sizeof(*mwl)) {
1065 		ret = -EIO;
1066 		goto out;
1067 	}
1068 
1069 	info->max_write_len = be16_to_cpu(mwl->len);
1070 
1071 out:
1072 	i3c_ccc_cmd_dest_cleanup(&dest);
1073 
1074 	return ret;
1075 }
1076 
1077 static int i3c_master_getmxds_locked(struct i3c_master_controller *master,
1078 				     struct i3c_device_info *info)
1079 {
1080 	struct i3c_ccc_getmxds *getmaxds;
1081 	struct i3c_ccc_cmd_dest dest;
1082 	struct i3c_ccc_cmd cmd;
1083 	int ret;
1084 
1085 	getmaxds = i3c_ccc_cmd_dest_init(&dest, info->dyn_addr,
1086 					 sizeof(*getmaxds));
1087 	if (!getmaxds)
1088 		return -ENOMEM;
1089 
1090 	i3c_ccc_cmd_init(&cmd, true, I3C_CCC_GETMXDS, &dest, 1);
1091 	ret = i3c_master_send_ccc_cmd_locked(master, &cmd);
1092 	if (ret)
1093 		goto out;
1094 
1095 	if (dest.payload.len != 2 && dest.payload.len != 5) {
1096 		ret = -EIO;
1097 		goto out;
1098 	}
1099 
1100 	info->max_read_ds = getmaxds->maxrd;
1101 	info->max_write_ds = getmaxds->maxwr;
1102 	if (dest.payload.len == 5)
1103 		info->max_read_turnaround = getmaxds->maxrdturn[0] |
1104 					    ((u32)getmaxds->maxrdturn[1] << 8) |
1105 					    ((u32)getmaxds->maxrdturn[2] << 16);
1106 
1107 out:
1108 	i3c_ccc_cmd_dest_cleanup(&dest);
1109 
1110 	return ret;
1111 }
1112 
1113 static int i3c_master_gethdrcap_locked(struct i3c_master_controller *master,
1114 				       struct i3c_device_info *info)
1115 {
1116 	struct i3c_ccc_gethdrcap *gethdrcap;
1117 	struct i3c_ccc_cmd_dest dest;
1118 	struct i3c_ccc_cmd cmd;
1119 	int ret;
1120 
1121 	gethdrcap = i3c_ccc_cmd_dest_init(&dest, info->dyn_addr,
1122 					  sizeof(*gethdrcap));
1123 	if (!gethdrcap)
1124 		return -ENOMEM;
1125 
1126 	i3c_ccc_cmd_init(&cmd, true, I3C_CCC_GETHDRCAP, &dest, 1);
1127 	ret = i3c_master_send_ccc_cmd_locked(master, &cmd);
1128 	if (ret)
1129 		goto out;
1130 
1131 	if (dest.payload.len != 1) {
1132 		ret = -EIO;
1133 		goto out;
1134 	}
1135 
1136 	info->hdr_cap = gethdrcap->modes;
1137 
1138 out:
1139 	i3c_ccc_cmd_dest_cleanup(&dest);
1140 
1141 	return ret;
1142 }
1143 
1144 static int i3c_master_getpid_locked(struct i3c_master_controller *master,
1145 				    struct i3c_device_info *info)
1146 {
1147 	struct i3c_ccc_getpid *getpid;
1148 	struct i3c_ccc_cmd_dest dest;
1149 	struct i3c_ccc_cmd cmd;
1150 	int ret, i;
1151 
1152 	getpid = i3c_ccc_cmd_dest_init(&dest, info->dyn_addr, sizeof(*getpid));
1153 	if (!getpid)
1154 		return -ENOMEM;
1155 
1156 	i3c_ccc_cmd_init(&cmd, true, I3C_CCC_GETPID, &dest, 1);
1157 	ret = i3c_master_send_ccc_cmd_locked(master, &cmd);
1158 	if (ret)
1159 		goto out;
1160 
1161 	info->pid = 0;
1162 	for (i = 0; i < sizeof(getpid->pid); i++) {
1163 		int sft = (sizeof(getpid->pid) - i - 1) * 8;
1164 
1165 		info->pid |= (u64)getpid->pid[i] << sft;
1166 	}
1167 
1168 out:
1169 	i3c_ccc_cmd_dest_cleanup(&dest);
1170 
1171 	return ret;
1172 }
1173 
1174 static int i3c_master_getbcr_locked(struct i3c_master_controller *master,
1175 				    struct i3c_device_info *info)
1176 {
1177 	struct i3c_ccc_getbcr *getbcr;
1178 	struct i3c_ccc_cmd_dest dest;
1179 	struct i3c_ccc_cmd cmd;
1180 	int ret;
1181 
1182 	getbcr = i3c_ccc_cmd_dest_init(&dest, info->dyn_addr, sizeof(*getbcr));
1183 	if (!getbcr)
1184 		return -ENOMEM;
1185 
1186 	i3c_ccc_cmd_init(&cmd, true, I3C_CCC_GETBCR, &dest, 1);
1187 	ret = i3c_master_send_ccc_cmd_locked(master, &cmd);
1188 	if (ret)
1189 		goto out;
1190 
1191 	info->bcr = getbcr->bcr;
1192 
1193 out:
1194 	i3c_ccc_cmd_dest_cleanup(&dest);
1195 
1196 	return ret;
1197 }
1198 
1199 static int i3c_master_getdcr_locked(struct i3c_master_controller *master,
1200 				    struct i3c_device_info *info)
1201 {
1202 	struct i3c_ccc_getdcr *getdcr;
1203 	struct i3c_ccc_cmd_dest dest;
1204 	struct i3c_ccc_cmd cmd;
1205 	int ret;
1206 
1207 	getdcr = i3c_ccc_cmd_dest_init(&dest, info->dyn_addr, sizeof(*getdcr));
1208 	if (!getdcr)
1209 		return -ENOMEM;
1210 
1211 	i3c_ccc_cmd_init(&cmd, true, I3C_CCC_GETDCR, &dest, 1);
1212 	ret = i3c_master_send_ccc_cmd_locked(master, &cmd);
1213 	if (ret)
1214 		goto out;
1215 
1216 	info->dcr = getdcr->dcr;
1217 
1218 out:
1219 	i3c_ccc_cmd_dest_cleanup(&dest);
1220 
1221 	return ret;
1222 }
1223 
1224 static int i3c_master_retrieve_dev_info(struct i3c_dev_desc *dev)
1225 {
1226 	struct i3c_master_controller *master = i3c_dev_get_master(dev);
1227 	enum i3c_addr_slot_status slot_status;
1228 	int ret;
1229 
1230 	if (!dev->info.dyn_addr)
1231 		return -EINVAL;
1232 
1233 	slot_status = i3c_bus_get_addr_slot_status(&master->bus,
1234 						   dev->info.dyn_addr);
1235 	if (slot_status == I3C_ADDR_SLOT_RSVD ||
1236 	    slot_status == I3C_ADDR_SLOT_I2C_DEV)
1237 		return -EINVAL;
1238 
1239 	ret = i3c_master_getpid_locked(master, &dev->info);
1240 	if (ret)
1241 		return ret;
1242 
1243 	ret = i3c_master_getbcr_locked(master, &dev->info);
1244 	if (ret)
1245 		return ret;
1246 
1247 	ret = i3c_master_getdcr_locked(master, &dev->info);
1248 	if (ret)
1249 		return ret;
1250 
1251 	if (dev->info.bcr & I3C_BCR_MAX_DATA_SPEED_LIM) {
1252 		ret = i3c_master_getmxds_locked(master, &dev->info);
1253 		if (ret)
1254 			return ret;
1255 	}
1256 
1257 	if (dev->info.bcr & I3C_BCR_IBI_PAYLOAD)
1258 		dev->info.max_ibi_len = 1;
1259 
1260 	i3c_master_getmrl_locked(master, &dev->info);
1261 	i3c_master_getmwl_locked(master, &dev->info);
1262 
1263 	if (dev->info.bcr & I3C_BCR_HDR_CAP) {
1264 		ret = i3c_master_gethdrcap_locked(master, &dev->info);
1265 		if (ret)
1266 			return ret;
1267 	}
1268 
1269 	return 0;
1270 }
1271 
1272 static void i3c_master_put_i3c_addrs(struct i3c_dev_desc *dev)
1273 {
1274 	struct i3c_master_controller *master = i3c_dev_get_master(dev);
1275 
1276 	if (dev->info.static_addr)
1277 		i3c_bus_set_addr_slot_status(&master->bus,
1278 					     dev->info.static_addr,
1279 					     I3C_ADDR_SLOT_FREE);
1280 
1281 	if (dev->info.dyn_addr)
1282 		i3c_bus_set_addr_slot_status(&master->bus, dev->info.dyn_addr,
1283 					     I3C_ADDR_SLOT_FREE);
1284 
1285 	if (dev->boardinfo && dev->boardinfo->init_dyn_addr)
1286 		i3c_bus_set_addr_slot_status(&master->bus, dev->info.dyn_addr,
1287 					     I3C_ADDR_SLOT_FREE);
1288 }
1289 
1290 static int i3c_master_get_i3c_addrs(struct i3c_dev_desc *dev)
1291 {
1292 	struct i3c_master_controller *master = i3c_dev_get_master(dev);
1293 	enum i3c_addr_slot_status status;
1294 
1295 	if (!dev->info.static_addr && !dev->info.dyn_addr)
1296 		return 0;
1297 
1298 	if (dev->info.static_addr) {
1299 		status = i3c_bus_get_addr_slot_status(&master->bus,
1300 						      dev->info.static_addr);
1301 		if (status != I3C_ADDR_SLOT_FREE)
1302 			return -EBUSY;
1303 
1304 		i3c_bus_set_addr_slot_status(&master->bus,
1305 					     dev->info.static_addr,
1306 					     I3C_ADDR_SLOT_I3C_DEV);
1307 	}
1308 
1309 	/*
1310 	 * ->init_dyn_addr should have been reserved before that, so, if we're
1311 	 * trying to apply a pre-reserved dynamic address, we should not try
1312 	 * to reserve the address slot a second time.
1313 	 */
1314 	if (dev->info.dyn_addr &&
1315 	    (!dev->boardinfo ||
1316 	     dev->boardinfo->init_dyn_addr != dev->info.dyn_addr)) {
1317 		status = i3c_bus_get_addr_slot_status(&master->bus,
1318 						      dev->info.dyn_addr);
1319 		if (status != I3C_ADDR_SLOT_FREE)
1320 			goto err_release_static_addr;
1321 
1322 		i3c_bus_set_addr_slot_status(&master->bus, dev->info.dyn_addr,
1323 					     I3C_ADDR_SLOT_I3C_DEV);
1324 	}
1325 
1326 	return 0;
1327 
1328 err_release_static_addr:
1329 	if (dev->info.static_addr)
1330 		i3c_bus_set_addr_slot_status(&master->bus,
1331 					     dev->info.static_addr,
1332 					     I3C_ADDR_SLOT_FREE);
1333 
1334 	return -EBUSY;
1335 }
1336 
1337 static int i3c_master_attach_i3c_dev(struct i3c_master_controller *master,
1338 				     struct i3c_dev_desc *dev)
1339 {
1340 	int ret;
1341 
1342 	/*
1343 	 * We don't attach devices to the controller until they are
1344 	 * addressable on the bus.
1345 	 */
1346 	if (!dev->info.static_addr && !dev->info.dyn_addr)
1347 		return 0;
1348 
1349 	ret = i3c_master_get_i3c_addrs(dev);
1350 	if (ret)
1351 		return ret;
1352 
1353 	/* Do not attach the master device itself. */
1354 	if (master->this != dev && master->ops->attach_i3c_dev) {
1355 		ret = master->ops->attach_i3c_dev(dev);
1356 		if (ret) {
1357 			i3c_master_put_i3c_addrs(dev);
1358 			return ret;
1359 		}
1360 	}
1361 
1362 	list_add_tail(&dev->common.node, &master->bus.devs.i3c);
1363 
1364 	return 0;
1365 }
1366 
1367 static int i3c_master_reattach_i3c_dev(struct i3c_dev_desc *dev,
1368 				       u8 old_dyn_addr)
1369 {
1370 	struct i3c_master_controller *master = i3c_dev_get_master(dev);
1371 	enum i3c_addr_slot_status status;
1372 	int ret;
1373 
1374 	if (dev->info.dyn_addr != old_dyn_addr &&
1375 	    (!dev->boardinfo ||
1376 	     dev->info.dyn_addr != dev->boardinfo->init_dyn_addr)) {
1377 		status = i3c_bus_get_addr_slot_status(&master->bus,
1378 						      dev->info.dyn_addr);
1379 		if (status != I3C_ADDR_SLOT_FREE)
1380 			return -EBUSY;
1381 		i3c_bus_set_addr_slot_status(&master->bus,
1382 					     dev->info.dyn_addr,
1383 					     I3C_ADDR_SLOT_I3C_DEV);
1384 	}
1385 
1386 	if (master->ops->reattach_i3c_dev) {
1387 		ret = master->ops->reattach_i3c_dev(dev, old_dyn_addr);
1388 		if (ret) {
1389 			i3c_master_put_i3c_addrs(dev);
1390 			return ret;
1391 		}
1392 	}
1393 
1394 	return 0;
1395 }
1396 
1397 static void i3c_master_detach_i3c_dev(struct i3c_dev_desc *dev)
1398 {
1399 	struct i3c_master_controller *master = i3c_dev_get_master(dev);
1400 
1401 	/* Do not detach the master device itself. */
1402 	if (master->this != dev && master->ops->detach_i3c_dev)
1403 		master->ops->detach_i3c_dev(dev);
1404 
1405 	i3c_master_put_i3c_addrs(dev);
1406 	list_del(&dev->common.node);
1407 }
1408 
1409 static int i3c_master_attach_i2c_dev(struct i3c_master_controller *master,
1410 				     struct i2c_dev_desc *dev)
1411 {
1412 	int ret;
1413 
1414 	if (master->ops->attach_i2c_dev) {
1415 		ret = master->ops->attach_i2c_dev(dev);
1416 		if (ret)
1417 			return ret;
1418 	}
1419 
1420 	list_add_tail(&dev->common.node, &master->bus.devs.i2c);
1421 
1422 	return 0;
1423 }
1424 
1425 static void i3c_master_detach_i2c_dev(struct i2c_dev_desc *dev)
1426 {
1427 	struct i3c_master_controller *master = i2c_dev_get_master(dev);
1428 
1429 	list_del(&dev->common.node);
1430 
1431 	if (master->ops->detach_i2c_dev)
1432 		master->ops->detach_i2c_dev(dev);
1433 }
1434 
1435 static int i3c_master_early_i3c_dev_add(struct i3c_master_controller *master,
1436 					  struct i3c_dev_boardinfo *boardinfo)
1437 {
1438 	struct i3c_device_info info = {
1439 		.static_addr = boardinfo->static_addr,
1440 	};
1441 	struct i3c_dev_desc *i3cdev;
1442 	int ret;
1443 
1444 	i3cdev = i3c_master_alloc_i3c_dev(master, &info);
1445 	if (IS_ERR(i3cdev))
1446 		return -ENOMEM;
1447 
1448 	i3cdev->boardinfo = boardinfo;
1449 
1450 	ret = i3c_master_attach_i3c_dev(master, i3cdev);
1451 	if (ret)
1452 		goto err_free_dev;
1453 
1454 	ret = i3c_master_setdasa_locked(master, i3cdev->info.static_addr,
1455 					i3cdev->boardinfo->init_dyn_addr);
1456 	if (ret)
1457 		goto err_detach_dev;
1458 
1459 	i3cdev->info.dyn_addr = i3cdev->boardinfo->init_dyn_addr;
1460 	ret = i3c_master_reattach_i3c_dev(i3cdev, 0);
1461 	if (ret)
1462 		goto err_rstdaa;
1463 
1464 	ret = i3c_master_retrieve_dev_info(i3cdev);
1465 	if (ret)
1466 		goto err_rstdaa;
1467 
1468 	return 0;
1469 
1470 err_rstdaa:
1471 	i3c_master_rstdaa_locked(master, i3cdev->boardinfo->init_dyn_addr);
1472 err_detach_dev:
1473 	i3c_master_detach_i3c_dev(i3cdev);
1474 err_free_dev:
1475 	i3c_master_free_i3c_dev(i3cdev);
1476 
1477 	return ret;
1478 }
1479 
1480 static void
1481 i3c_master_register_new_i3c_devs(struct i3c_master_controller *master)
1482 {
1483 	struct i3c_dev_desc *desc;
1484 	int ret;
1485 
1486 	if (!master->init_done)
1487 		return;
1488 
1489 	i3c_bus_for_each_i3cdev(&master->bus, desc) {
1490 		if (desc->dev || !desc->info.dyn_addr || desc == master->this)
1491 			continue;
1492 
1493 		desc->dev = kzalloc(sizeof(*desc->dev), GFP_KERNEL);
1494 		if (!desc->dev)
1495 			continue;
1496 
1497 		desc->dev->bus = &master->bus;
1498 		desc->dev->desc = desc;
1499 		desc->dev->dev.parent = &master->dev;
1500 		desc->dev->dev.type = &i3c_device_type;
1501 		desc->dev->dev.bus = &i3c_bus_type;
1502 		desc->dev->dev.release = i3c_device_release;
1503 		dev_set_name(&desc->dev->dev, "%d-%llx", master->bus.id,
1504 			     desc->info.pid);
1505 
1506 		if (desc->boardinfo)
1507 			desc->dev->dev.of_node = desc->boardinfo->of_node;
1508 
1509 		ret = device_register(&desc->dev->dev);
1510 		if (ret)
1511 			dev_err(&master->dev,
1512 				"Failed to add I3C device (err = %d)\n", ret);
1513 	}
1514 }
1515 
1516 /**
1517  * i3c_master_do_daa() - do a DAA (Dynamic Address Assignment)
1518  * @master: master doing the DAA
1519  *
1520  * This function is instantiating an I3C device object and adding it to the
1521  * I3C device list. All device information are automatically retrieved using
1522  * standard CCC commands.
1523  *
1524  * The I3C device object is returned in case the master wants to attach
1525  * private data to it using i3c_dev_set_master_data().
1526  *
1527  * This function must be called with the bus lock held in write mode.
1528  *
1529  * Return: a 0 in case of success, an negative error code otherwise.
1530  */
1531 int i3c_master_do_daa(struct i3c_master_controller *master)
1532 {
1533 	int ret;
1534 
1535 	i3c_bus_maintenance_lock(&master->bus);
1536 	ret = master->ops->do_daa(master);
1537 	i3c_bus_maintenance_unlock(&master->bus);
1538 
1539 	if (ret)
1540 		return ret;
1541 
1542 	i3c_bus_normaluse_lock(&master->bus);
1543 	i3c_master_register_new_i3c_devs(master);
1544 	i3c_bus_normaluse_unlock(&master->bus);
1545 
1546 	return 0;
1547 }
1548 EXPORT_SYMBOL_GPL(i3c_master_do_daa);
1549 
1550 /**
1551  * i3c_master_set_info() - set master device information
1552  * @master: master used to send frames on the bus
1553  * @info: I3C device information
1554  *
1555  * Set master device info. This should be called from
1556  * &i3c_master_controller_ops->bus_init().
1557  *
1558  * Not all &i3c_device_info fields are meaningful for a master device.
1559  * Here is a list of fields that should be properly filled:
1560  *
1561  * - &i3c_device_info->dyn_addr
1562  * - &i3c_device_info->bcr
1563  * - &i3c_device_info->dcr
1564  * - &i3c_device_info->pid
1565  * - &i3c_device_info->hdr_cap if %I3C_BCR_HDR_CAP bit is set in
1566  *   &i3c_device_info->bcr
1567  *
1568  * This function must be called with the bus lock held in maintenance mode.
1569  *
1570  * Return: 0 if @info contains valid information (not every piece of
1571  * information can be checked, but we can at least make sure @info->dyn_addr
1572  * and @info->bcr are correct), -EINVAL otherwise.
1573  */
1574 int i3c_master_set_info(struct i3c_master_controller *master,
1575 			const struct i3c_device_info *info)
1576 {
1577 	struct i3c_dev_desc *i3cdev;
1578 	int ret;
1579 
1580 	if (!i3c_bus_dev_addr_is_avail(&master->bus, info->dyn_addr))
1581 		return -EINVAL;
1582 
1583 	if (I3C_BCR_DEVICE_ROLE(info->bcr) == I3C_BCR_I3C_MASTER &&
1584 	    master->secondary)
1585 		return -EINVAL;
1586 
1587 	if (master->this)
1588 		return -EINVAL;
1589 
1590 	i3cdev = i3c_master_alloc_i3c_dev(master, info);
1591 	if (IS_ERR(i3cdev))
1592 		return PTR_ERR(i3cdev);
1593 
1594 	master->this = i3cdev;
1595 	master->bus.cur_master = master->this;
1596 
1597 	ret = i3c_master_attach_i3c_dev(master, i3cdev);
1598 	if (ret)
1599 		goto err_free_dev;
1600 
1601 	return 0;
1602 
1603 err_free_dev:
1604 	i3c_master_free_i3c_dev(i3cdev);
1605 
1606 	return ret;
1607 }
1608 EXPORT_SYMBOL_GPL(i3c_master_set_info);
1609 
1610 static void i3c_master_detach_free_devs(struct i3c_master_controller *master)
1611 {
1612 	struct i3c_dev_desc *i3cdev, *i3ctmp;
1613 	struct i2c_dev_desc *i2cdev, *i2ctmp;
1614 
1615 	list_for_each_entry_safe(i3cdev, i3ctmp, &master->bus.devs.i3c,
1616 				 common.node) {
1617 		i3c_master_detach_i3c_dev(i3cdev);
1618 
1619 		if (i3cdev->boardinfo && i3cdev->boardinfo->init_dyn_addr)
1620 			i3c_bus_set_addr_slot_status(&master->bus,
1621 					i3cdev->boardinfo->init_dyn_addr,
1622 					I3C_ADDR_SLOT_FREE);
1623 
1624 		i3c_master_free_i3c_dev(i3cdev);
1625 	}
1626 
1627 	list_for_each_entry_safe(i2cdev, i2ctmp, &master->bus.devs.i2c,
1628 				 common.node) {
1629 		i3c_master_detach_i2c_dev(i2cdev);
1630 		i3c_bus_set_addr_slot_status(&master->bus,
1631 					     i2cdev->addr,
1632 					     I3C_ADDR_SLOT_FREE);
1633 		i3c_master_free_i2c_dev(i2cdev);
1634 	}
1635 }
1636 
1637 /**
1638  * i3c_master_bus_init() - initialize an I3C bus
1639  * @master: main master initializing the bus
1640  *
1641  * This function is following all initialisation steps described in the I3C
1642  * specification:
1643  *
1644  * 1. Attach I2C devs to the master so that the master can fill its internal
1645  *    device table appropriately
1646  *
1647  * 2. Call &i3c_master_controller_ops->bus_init() method to initialize
1648  *    the master controller. That's usually where the bus mode is selected
1649  *    (pure bus or mixed fast/slow bus)
1650  *
1651  * 3. Instruct all devices on the bus to drop their dynamic address. This is
1652  *    particularly important when the bus was previously configured by someone
1653  *    else (for example the bootloader)
1654  *
1655  * 4. Disable all slave events.
1656  *
1657  * 5. Reserve address slots for I3C devices with init_dyn_addr. And if devices
1658  *    also have static_addr, try to pre-assign dynamic addresses requested by
1659  *    the FW with SETDASA and attach corresponding statically defined I3C
1660  *    devices to the master.
1661  *
1662  * 6. Do a DAA (Dynamic Address Assignment) to assign dynamic addresses to all
1663  *    remaining I3C devices
1664  *
1665  * Once this is done, all I3C and I2C devices should be usable.
1666  *
1667  * Return: a 0 in case of success, an negative error code otherwise.
1668  */
1669 static int i3c_master_bus_init(struct i3c_master_controller *master)
1670 {
1671 	enum i3c_addr_slot_status status;
1672 	struct i2c_dev_boardinfo *i2cboardinfo;
1673 	struct i3c_dev_boardinfo *i3cboardinfo;
1674 	struct i2c_dev_desc *i2cdev;
1675 	int ret;
1676 
1677 	/*
1678 	 * First attach all devices with static definitions provided by the
1679 	 * FW.
1680 	 */
1681 	list_for_each_entry(i2cboardinfo, &master->boardinfo.i2c, node) {
1682 		status = i3c_bus_get_addr_slot_status(&master->bus,
1683 						      i2cboardinfo->base.addr);
1684 		if (status != I3C_ADDR_SLOT_FREE) {
1685 			ret = -EBUSY;
1686 			goto err_detach_devs;
1687 		}
1688 
1689 		i3c_bus_set_addr_slot_status(&master->bus,
1690 					     i2cboardinfo->base.addr,
1691 					     I3C_ADDR_SLOT_I2C_DEV);
1692 
1693 		i2cdev = i3c_master_alloc_i2c_dev(master, i2cboardinfo);
1694 		if (IS_ERR(i2cdev)) {
1695 			ret = PTR_ERR(i2cdev);
1696 			goto err_detach_devs;
1697 		}
1698 
1699 		ret = i3c_master_attach_i2c_dev(master, i2cdev);
1700 		if (ret) {
1701 			i3c_master_free_i2c_dev(i2cdev);
1702 			goto err_detach_devs;
1703 		}
1704 	}
1705 
1706 	/*
1707 	 * Now execute the controller specific ->bus_init() routine, which
1708 	 * might configure its internal logic to match the bus limitations.
1709 	 */
1710 	ret = master->ops->bus_init(master);
1711 	if (ret)
1712 		goto err_detach_devs;
1713 
1714 	/*
1715 	 * The master device should have been instantiated in ->bus_init(),
1716 	 * complain if this was not the case.
1717 	 */
1718 	if (!master->this) {
1719 		dev_err(&master->dev,
1720 			"master_set_info() was not called in ->bus_init()\n");
1721 		ret = -EINVAL;
1722 		goto err_bus_cleanup;
1723 	}
1724 
1725 	/*
1726 	 * Reset all dynamic address that may have been assigned before
1727 	 * (assigned by the bootloader for example).
1728 	 */
1729 	ret = i3c_master_rstdaa_locked(master, I3C_BROADCAST_ADDR);
1730 	if (ret && ret != I3C_ERROR_M2)
1731 		goto err_bus_cleanup;
1732 
1733 	/* Disable all slave events before starting DAA. */
1734 	ret = i3c_master_disec_locked(master, I3C_BROADCAST_ADDR,
1735 				      I3C_CCC_EVENT_SIR | I3C_CCC_EVENT_MR |
1736 				      I3C_CCC_EVENT_HJ);
1737 	if (ret && ret != I3C_ERROR_M2)
1738 		goto err_bus_cleanup;
1739 
1740 	/*
1741 	 * Reserve init_dyn_addr first, and then try to pre-assign dynamic
1742 	 * address and retrieve device information if needed.
1743 	 * In case pre-assign dynamic address fails, setting dynamic address to
1744 	 * the requested init_dyn_addr is retried after DAA is done in
1745 	 * i3c_master_add_i3c_dev_locked().
1746 	 */
1747 	list_for_each_entry(i3cboardinfo, &master->boardinfo.i3c, node) {
1748 
1749 		/*
1750 		 * We don't reserve a dynamic address for devices that
1751 		 * don't explicitly request one.
1752 		 */
1753 		if (!i3cboardinfo->init_dyn_addr)
1754 			continue;
1755 
1756 		ret = i3c_bus_get_addr_slot_status(&master->bus,
1757 						   i3cboardinfo->init_dyn_addr);
1758 		if (ret != I3C_ADDR_SLOT_FREE) {
1759 			ret = -EBUSY;
1760 			goto err_rstdaa;
1761 		}
1762 
1763 		i3c_bus_set_addr_slot_status(&master->bus,
1764 					     i3cboardinfo->init_dyn_addr,
1765 					     I3C_ADDR_SLOT_I3C_DEV);
1766 
1767 		/*
1768 		 * Only try to create/attach devices that have a static
1769 		 * address. Other devices will be created/attached when
1770 		 * DAA happens, and the requested dynamic address will
1771 		 * be set using SETNEWDA once those devices become
1772 		 * addressable.
1773 		 */
1774 
1775 		if (i3cboardinfo->static_addr)
1776 			i3c_master_early_i3c_dev_add(master, i3cboardinfo);
1777 	}
1778 
1779 	ret = i3c_master_do_daa(master);
1780 	if (ret)
1781 		goto err_rstdaa;
1782 
1783 	return 0;
1784 
1785 err_rstdaa:
1786 	i3c_master_rstdaa_locked(master, I3C_BROADCAST_ADDR);
1787 
1788 err_bus_cleanup:
1789 	if (master->ops->bus_cleanup)
1790 		master->ops->bus_cleanup(master);
1791 
1792 err_detach_devs:
1793 	i3c_master_detach_free_devs(master);
1794 
1795 	return ret;
1796 }
1797 
1798 static void i3c_master_bus_cleanup(struct i3c_master_controller *master)
1799 {
1800 	if (master->ops->bus_cleanup)
1801 		master->ops->bus_cleanup(master);
1802 
1803 	i3c_master_detach_free_devs(master);
1804 }
1805 
1806 static void i3c_master_attach_boardinfo(struct i3c_dev_desc *i3cdev)
1807 {
1808 	struct i3c_master_controller *master = i3cdev->common.master;
1809 	struct i3c_dev_boardinfo *i3cboardinfo;
1810 
1811 	list_for_each_entry(i3cboardinfo, &master->boardinfo.i3c, node) {
1812 		if (i3cdev->info.pid != i3cboardinfo->pid)
1813 			continue;
1814 
1815 		i3cdev->boardinfo = i3cboardinfo;
1816 		i3cdev->info.static_addr = i3cboardinfo->static_addr;
1817 		return;
1818 	}
1819 }
1820 
1821 static struct i3c_dev_desc *
1822 i3c_master_search_i3c_dev_duplicate(struct i3c_dev_desc *refdev)
1823 {
1824 	struct i3c_master_controller *master = i3c_dev_get_master(refdev);
1825 	struct i3c_dev_desc *i3cdev;
1826 
1827 	i3c_bus_for_each_i3cdev(&master->bus, i3cdev) {
1828 		if (i3cdev != refdev && i3cdev->info.pid == refdev->info.pid)
1829 			return i3cdev;
1830 	}
1831 
1832 	return NULL;
1833 }
1834 
1835 /**
1836  * i3c_master_add_i3c_dev_locked() - add an I3C slave to the bus
1837  * @master: master used to send frames on the bus
1838  * @addr: I3C slave dynamic address assigned to the device
1839  *
1840  * This function is instantiating an I3C device object and adding it to the
1841  * I3C device list. All device information are automatically retrieved using
1842  * standard CCC commands.
1843  *
1844  * The I3C device object is returned in case the master wants to attach
1845  * private data to it using i3c_dev_set_master_data().
1846  *
1847  * This function must be called with the bus lock held in write mode.
1848  *
1849  * Return: a 0 in case of success, an negative error code otherwise.
1850  */
1851 int i3c_master_add_i3c_dev_locked(struct i3c_master_controller *master,
1852 				  u8 addr)
1853 {
1854 	struct i3c_device_info info = { .dyn_addr = addr };
1855 	struct i3c_dev_desc *newdev, *olddev;
1856 	u8 old_dyn_addr = addr, expected_dyn_addr;
1857 	struct i3c_ibi_setup ibireq = { };
1858 	bool enable_ibi = false;
1859 	int ret;
1860 
1861 	if (!master)
1862 		return -EINVAL;
1863 
1864 	newdev = i3c_master_alloc_i3c_dev(master, &info);
1865 	if (IS_ERR(newdev))
1866 		return PTR_ERR(newdev);
1867 
1868 	ret = i3c_master_attach_i3c_dev(master, newdev);
1869 	if (ret)
1870 		goto err_free_dev;
1871 
1872 	ret = i3c_master_retrieve_dev_info(newdev);
1873 	if (ret)
1874 		goto err_detach_dev;
1875 
1876 	i3c_master_attach_boardinfo(newdev);
1877 
1878 	olddev = i3c_master_search_i3c_dev_duplicate(newdev);
1879 	if (olddev) {
1880 		newdev->dev = olddev->dev;
1881 		if (newdev->dev)
1882 			newdev->dev->desc = newdev;
1883 
1884 		/*
1885 		 * We need to restore the IBI state too, so let's save the
1886 		 * IBI information and try to restore them after olddev has
1887 		 * been detached+released and its IBI has been stopped and
1888 		 * the associated resources have been freed.
1889 		 */
1890 		mutex_lock(&olddev->ibi_lock);
1891 		if (olddev->ibi) {
1892 			ibireq.handler = olddev->ibi->handler;
1893 			ibireq.max_payload_len = olddev->ibi->max_payload_len;
1894 			ibireq.num_slots = olddev->ibi->num_slots;
1895 
1896 			if (olddev->ibi->enabled) {
1897 				enable_ibi = true;
1898 				i3c_dev_disable_ibi_locked(olddev);
1899 			}
1900 
1901 			i3c_dev_free_ibi_locked(olddev);
1902 		}
1903 		mutex_unlock(&olddev->ibi_lock);
1904 
1905 		old_dyn_addr = olddev->info.dyn_addr;
1906 
1907 		i3c_master_detach_i3c_dev(olddev);
1908 		i3c_master_free_i3c_dev(olddev);
1909 	}
1910 
1911 	ret = i3c_master_reattach_i3c_dev(newdev, old_dyn_addr);
1912 	if (ret)
1913 		goto err_detach_dev;
1914 
1915 	/*
1916 	 * Depending on our previous state, the expected dynamic address might
1917 	 * differ:
1918 	 * - if the device already had a dynamic address assigned, let's try to
1919 	 *   re-apply this one
1920 	 * - if the device did not have a dynamic address and the firmware
1921 	 *   requested a specific address, pick this one
1922 	 * - in any other case, keep the address automatically assigned by the
1923 	 *   master
1924 	 */
1925 	if (old_dyn_addr && old_dyn_addr != newdev->info.dyn_addr)
1926 		expected_dyn_addr = old_dyn_addr;
1927 	else if (newdev->boardinfo && newdev->boardinfo->init_dyn_addr)
1928 		expected_dyn_addr = newdev->boardinfo->init_dyn_addr;
1929 	else
1930 		expected_dyn_addr = newdev->info.dyn_addr;
1931 
1932 	if (newdev->info.dyn_addr != expected_dyn_addr) {
1933 		/*
1934 		 * Try to apply the expected dynamic address. If it fails, keep
1935 		 * the address assigned by the master.
1936 		 */
1937 		ret = i3c_master_setnewda_locked(master,
1938 						 newdev->info.dyn_addr,
1939 						 expected_dyn_addr);
1940 		if (!ret) {
1941 			old_dyn_addr = newdev->info.dyn_addr;
1942 			newdev->info.dyn_addr = expected_dyn_addr;
1943 			i3c_master_reattach_i3c_dev(newdev, old_dyn_addr);
1944 		} else {
1945 			dev_err(&master->dev,
1946 				"Failed to assign reserved/old address to device %d%llx",
1947 				master->bus.id, newdev->info.pid);
1948 		}
1949 	}
1950 
1951 	/*
1952 	 * Now is time to try to restore the IBI setup. If we're lucky,
1953 	 * everything works as before, otherwise, all we can do is complain.
1954 	 * FIXME: maybe we should add callback to inform the driver that it
1955 	 * should request the IBI again instead of trying to hide that from
1956 	 * him.
1957 	 */
1958 	if (ibireq.handler) {
1959 		mutex_lock(&newdev->ibi_lock);
1960 		ret = i3c_dev_request_ibi_locked(newdev, &ibireq);
1961 		if (ret) {
1962 			dev_err(&master->dev,
1963 				"Failed to request IBI on device %d-%llx",
1964 				master->bus.id, newdev->info.pid);
1965 		} else if (enable_ibi) {
1966 			ret = i3c_dev_enable_ibi_locked(newdev);
1967 			if (ret)
1968 				dev_err(&master->dev,
1969 					"Failed to re-enable IBI on device %d-%llx",
1970 					master->bus.id, newdev->info.pid);
1971 		}
1972 		mutex_unlock(&newdev->ibi_lock);
1973 	}
1974 
1975 	return 0;
1976 
1977 err_detach_dev:
1978 	if (newdev->dev && newdev->dev->desc)
1979 		newdev->dev->desc = NULL;
1980 
1981 	i3c_master_detach_i3c_dev(newdev);
1982 
1983 err_free_dev:
1984 	i3c_master_free_i3c_dev(newdev);
1985 
1986 	return ret;
1987 }
1988 EXPORT_SYMBOL_GPL(i3c_master_add_i3c_dev_locked);
1989 
1990 #define OF_I3C_REG1_IS_I2C_DEV			BIT(31)
1991 
1992 static int
1993 of_i3c_master_add_i2c_boardinfo(struct i3c_master_controller *master,
1994 				struct device_node *node, u32 *reg)
1995 {
1996 	struct i2c_dev_boardinfo *boardinfo;
1997 	struct device *dev = &master->dev;
1998 	int ret;
1999 
2000 	boardinfo = devm_kzalloc(dev, sizeof(*boardinfo), GFP_KERNEL);
2001 	if (!boardinfo)
2002 		return -ENOMEM;
2003 
2004 	ret = of_i2c_get_board_info(dev, node, &boardinfo->base);
2005 	if (ret)
2006 		return ret;
2007 
2008 	/*
2009 	 * The I3C Specification does not clearly say I2C devices with 10-bit
2010 	 * address are supported. These devices can't be passed properly through
2011 	 * DEFSLVS command.
2012 	 */
2013 	if (boardinfo->base.flags & I2C_CLIENT_TEN) {
2014 		dev_err(dev, "I2C device with 10 bit address not supported.");
2015 		return -ENOTSUPP;
2016 	}
2017 
2018 	/* LVR is encoded in reg[2]. */
2019 	boardinfo->lvr = reg[2];
2020 
2021 	list_add_tail(&boardinfo->node, &master->boardinfo.i2c);
2022 	of_node_get(node);
2023 
2024 	return 0;
2025 }
2026 
2027 static int
2028 of_i3c_master_add_i3c_boardinfo(struct i3c_master_controller *master,
2029 				struct device_node *node, u32 *reg)
2030 {
2031 	struct i3c_dev_boardinfo *boardinfo;
2032 	struct device *dev = &master->dev;
2033 	enum i3c_addr_slot_status addrstatus;
2034 	u32 init_dyn_addr = 0;
2035 
2036 	boardinfo = devm_kzalloc(dev, sizeof(*boardinfo), GFP_KERNEL);
2037 	if (!boardinfo)
2038 		return -ENOMEM;
2039 
2040 	if (reg[0]) {
2041 		if (reg[0] > I3C_MAX_ADDR)
2042 			return -EINVAL;
2043 
2044 		addrstatus = i3c_bus_get_addr_slot_status(&master->bus,
2045 							  reg[0]);
2046 		if (addrstatus != I3C_ADDR_SLOT_FREE)
2047 			return -EINVAL;
2048 	}
2049 
2050 	boardinfo->static_addr = reg[0];
2051 
2052 	if (!of_property_read_u32(node, "assigned-address", &init_dyn_addr)) {
2053 		if (init_dyn_addr > I3C_MAX_ADDR)
2054 			return -EINVAL;
2055 
2056 		addrstatus = i3c_bus_get_addr_slot_status(&master->bus,
2057 							  init_dyn_addr);
2058 		if (addrstatus != I3C_ADDR_SLOT_FREE)
2059 			return -EINVAL;
2060 	}
2061 
2062 	boardinfo->pid = ((u64)reg[1] << 32) | reg[2];
2063 
2064 	if ((boardinfo->pid & GENMASK_ULL(63, 48)) ||
2065 	    I3C_PID_RND_LOWER_32BITS(boardinfo->pid))
2066 		return -EINVAL;
2067 
2068 	boardinfo->init_dyn_addr = init_dyn_addr;
2069 	boardinfo->of_node = of_node_get(node);
2070 	list_add_tail(&boardinfo->node, &master->boardinfo.i3c);
2071 
2072 	return 0;
2073 }
2074 
2075 static int of_i3c_master_add_dev(struct i3c_master_controller *master,
2076 				 struct device_node *node)
2077 {
2078 	u32 reg[3];
2079 	int ret;
2080 
2081 	if (!master || !node)
2082 		return -EINVAL;
2083 
2084 	ret = of_property_read_u32_array(node, "reg", reg, ARRAY_SIZE(reg));
2085 	if (ret)
2086 		return ret;
2087 
2088 	/*
2089 	 * The manufacturer ID can't be 0. If reg[1] == 0 that means we're
2090 	 * dealing with an I2C device.
2091 	 */
2092 	if (!reg[1])
2093 		ret = of_i3c_master_add_i2c_boardinfo(master, node, reg);
2094 	else
2095 		ret = of_i3c_master_add_i3c_boardinfo(master, node, reg);
2096 
2097 	return ret;
2098 }
2099 
2100 static int of_populate_i3c_bus(struct i3c_master_controller *master)
2101 {
2102 	struct device *dev = &master->dev;
2103 	struct device_node *i3cbus_np = dev->of_node;
2104 	struct device_node *node;
2105 	int ret;
2106 	u32 val;
2107 
2108 	if (!i3cbus_np)
2109 		return 0;
2110 
2111 	for_each_available_child_of_node(i3cbus_np, node) {
2112 		ret = of_i3c_master_add_dev(master, node);
2113 		if (ret) {
2114 			of_node_put(node);
2115 			return ret;
2116 		}
2117 	}
2118 
2119 	/*
2120 	 * The user might want to limit I2C and I3C speed in case some devices
2121 	 * on the bus are not supporting typical rates, or if the bus topology
2122 	 * prevents it from using max possible rate.
2123 	 */
2124 	if (!of_property_read_u32(i3cbus_np, "i2c-scl-hz", &val))
2125 		master->bus.scl_rate.i2c = val;
2126 
2127 	if (!of_property_read_u32(i3cbus_np, "i3c-scl-hz", &val))
2128 		master->bus.scl_rate.i3c = val;
2129 
2130 	return 0;
2131 }
2132 
2133 static int i3c_master_i2c_adapter_xfer(struct i2c_adapter *adap,
2134 				       struct i2c_msg *xfers, int nxfers)
2135 {
2136 	struct i3c_master_controller *master = i2c_adapter_to_i3c_master(adap);
2137 	struct i2c_dev_desc *dev;
2138 	int i, ret;
2139 	u16 addr;
2140 
2141 	if (!xfers || !master || nxfers <= 0)
2142 		return -EINVAL;
2143 
2144 	if (!master->ops->i2c_xfers)
2145 		return -ENOTSUPP;
2146 
2147 	/* Doing transfers to different devices is not supported. */
2148 	addr = xfers[0].addr;
2149 	for (i = 1; i < nxfers; i++) {
2150 		if (addr != xfers[i].addr)
2151 			return -ENOTSUPP;
2152 	}
2153 
2154 	i3c_bus_normaluse_lock(&master->bus);
2155 	dev = i3c_master_find_i2c_dev_by_addr(master, addr);
2156 	if (!dev)
2157 		ret = -ENOENT;
2158 	else
2159 		ret = master->ops->i2c_xfers(dev, xfers, nxfers);
2160 	i3c_bus_normaluse_unlock(&master->bus);
2161 
2162 	return ret ? ret : nxfers;
2163 }
2164 
2165 static u32 i3c_master_i2c_funcs(struct i2c_adapter *adapter)
2166 {
2167 	return I2C_FUNC_SMBUS_EMUL | I2C_FUNC_I2C;
2168 }
2169 
2170 static const struct i2c_algorithm i3c_master_i2c_algo = {
2171 	.master_xfer = i3c_master_i2c_adapter_xfer,
2172 	.functionality = i3c_master_i2c_funcs,
2173 };
2174 
2175 static int i3c_master_i2c_adapter_init(struct i3c_master_controller *master)
2176 {
2177 	struct i2c_adapter *adap = i3c_master_to_i2c_adapter(master);
2178 	struct i2c_dev_desc *i2cdev;
2179 	int ret;
2180 
2181 	adap->dev.parent = master->dev.parent;
2182 	adap->owner = master->dev.parent->driver->owner;
2183 	adap->algo = &i3c_master_i2c_algo;
2184 	strncpy(adap->name, dev_name(master->dev.parent), sizeof(adap->name));
2185 
2186 	/* FIXME: Should we allow i3c masters to override these values? */
2187 	adap->timeout = 1000;
2188 	adap->retries = 3;
2189 
2190 	ret = i2c_add_adapter(adap);
2191 	if (ret)
2192 		return ret;
2193 
2194 	/*
2195 	 * We silently ignore failures here. The bus should keep working
2196 	 * correctly even if one or more i2c devices are not registered.
2197 	 */
2198 	i3c_bus_for_each_i2cdev(&master->bus, i2cdev)
2199 		i2cdev->dev = i2c_new_client_device(adap, &i2cdev->boardinfo->base);
2200 
2201 	return 0;
2202 }
2203 
2204 static void i3c_master_i2c_adapter_cleanup(struct i3c_master_controller *master)
2205 {
2206 	struct i2c_dev_desc *i2cdev;
2207 
2208 	i2c_del_adapter(&master->i2c);
2209 
2210 	i3c_bus_for_each_i2cdev(&master->bus, i2cdev)
2211 		i2cdev->dev = NULL;
2212 }
2213 
2214 static void i3c_master_unregister_i3c_devs(struct i3c_master_controller *master)
2215 {
2216 	struct i3c_dev_desc *i3cdev;
2217 
2218 	i3c_bus_for_each_i3cdev(&master->bus, i3cdev) {
2219 		if (!i3cdev->dev)
2220 			continue;
2221 
2222 		i3cdev->dev->desc = NULL;
2223 		if (device_is_registered(&i3cdev->dev->dev))
2224 			device_unregister(&i3cdev->dev->dev);
2225 		else
2226 			put_device(&i3cdev->dev->dev);
2227 		i3cdev->dev = NULL;
2228 	}
2229 }
2230 
2231 /**
2232  * i3c_master_queue_ibi() - Queue an IBI
2233  * @dev: the device this IBI is coming from
2234  * @slot: the IBI slot used to store the payload
2235  *
2236  * Queue an IBI to the controller workqueue. The IBI handler attached to
2237  * the dev will be called from a workqueue context.
2238  */
2239 void i3c_master_queue_ibi(struct i3c_dev_desc *dev, struct i3c_ibi_slot *slot)
2240 {
2241 	atomic_inc(&dev->ibi->pending_ibis);
2242 	queue_work(dev->common.master->wq, &slot->work);
2243 }
2244 EXPORT_SYMBOL_GPL(i3c_master_queue_ibi);
2245 
2246 static void i3c_master_handle_ibi(struct work_struct *work)
2247 {
2248 	struct i3c_ibi_slot *slot = container_of(work, struct i3c_ibi_slot,
2249 						 work);
2250 	struct i3c_dev_desc *dev = slot->dev;
2251 	struct i3c_master_controller *master = i3c_dev_get_master(dev);
2252 	struct i3c_ibi_payload payload;
2253 
2254 	payload.data = slot->data;
2255 	payload.len = slot->len;
2256 
2257 	if (dev->dev)
2258 		dev->ibi->handler(dev->dev, &payload);
2259 
2260 	master->ops->recycle_ibi_slot(dev, slot);
2261 	if (atomic_dec_and_test(&dev->ibi->pending_ibis))
2262 		complete(&dev->ibi->all_ibis_handled);
2263 }
2264 
2265 static void i3c_master_init_ibi_slot(struct i3c_dev_desc *dev,
2266 				     struct i3c_ibi_slot *slot)
2267 {
2268 	slot->dev = dev;
2269 	INIT_WORK(&slot->work, i3c_master_handle_ibi);
2270 }
2271 
2272 struct i3c_generic_ibi_slot {
2273 	struct list_head node;
2274 	struct i3c_ibi_slot base;
2275 };
2276 
2277 struct i3c_generic_ibi_pool {
2278 	spinlock_t lock;
2279 	unsigned int num_slots;
2280 	struct i3c_generic_ibi_slot *slots;
2281 	void *payload_buf;
2282 	struct list_head free_slots;
2283 	struct list_head pending;
2284 };
2285 
2286 /**
2287  * i3c_generic_ibi_free_pool() - Free a generic IBI pool
2288  * @pool: the IBI pool to free
2289  *
2290  * Free all IBI slots allated by a generic IBI pool.
2291  */
2292 void i3c_generic_ibi_free_pool(struct i3c_generic_ibi_pool *pool)
2293 {
2294 	struct i3c_generic_ibi_slot *slot;
2295 	unsigned int nslots = 0;
2296 
2297 	while (!list_empty(&pool->free_slots)) {
2298 		slot = list_first_entry(&pool->free_slots,
2299 					struct i3c_generic_ibi_slot, node);
2300 		list_del(&slot->node);
2301 		nslots++;
2302 	}
2303 
2304 	/*
2305 	 * If the number of freed slots is not equal to the number of allocated
2306 	 * slots we have a leak somewhere.
2307 	 */
2308 	WARN_ON(nslots != pool->num_slots);
2309 
2310 	kfree(pool->payload_buf);
2311 	kfree(pool->slots);
2312 	kfree(pool);
2313 }
2314 EXPORT_SYMBOL_GPL(i3c_generic_ibi_free_pool);
2315 
2316 /**
2317  * i3c_generic_ibi_alloc_pool() - Create a generic IBI pool
2318  * @dev: the device this pool will be used for
2319  * @req: IBI setup request describing what the device driver expects
2320  *
2321  * Create a generic IBI pool based on the information provided in @req.
2322  *
2323  * Return: a valid IBI pool in case of success, an ERR_PTR() otherwise.
2324  */
2325 struct i3c_generic_ibi_pool *
2326 i3c_generic_ibi_alloc_pool(struct i3c_dev_desc *dev,
2327 			   const struct i3c_ibi_setup *req)
2328 {
2329 	struct i3c_generic_ibi_pool *pool;
2330 	struct i3c_generic_ibi_slot *slot;
2331 	unsigned int i;
2332 	int ret;
2333 
2334 	pool = kzalloc(sizeof(*pool), GFP_KERNEL);
2335 	if (!pool)
2336 		return ERR_PTR(-ENOMEM);
2337 
2338 	spin_lock_init(&pool->lock);
2339 	INIT_LIST_HEAD(&pool->free_slots);
2340 	INIT_LIST_HEAD(&pool->pending);
2341 
2342 	pool->slots = kcalloc(req->num_slots, sizeof(*slot), GFP_KERNEL);
2343 	if (!pool->slots) {
2344 		ret = -ENOMEM;
2345 		goto err_free_pool;
2346 	}
2347 
2348 	if (req->max_payload_len) {
2349 		pool->payload_buf = kcalloc(req->num_slots,
2350 					    req->max_payload_len, GFP_KERNEL);
2351 		if (!pool->payload_buf) {
2352 			ret = -ENOMEM;
2353 			goto err_free_pool;
2354 		}
2355 	}
2356 
2357 	for (i = 0; i < req->num_slots; i++) {
2358 		slot = &pool->slots[i];
2359 		i3c_master_init_ibi_slot(dev, &slot->base);
2360 
2361 		if (req->max_payload_len)
2362 			slot->base.data = pool->payload_buf +
2363 					  (i * req->max_payload_len);
2364 
2365 		list_add_tail(&slot->node, &pool->free_slots);
2366 		pool->num_slots++;
2367 	}
2368 
2369 	return pool;
2370 
2371 err_free_pool:
2372 	i3c_generic_ibi_free_pool(pool);
2373 	return ERR_PTR(ret);
2374 }
2375 EXPORT_SYMBOL_GPL(i3c_generic_ibi_alloc_pool);
2376 
2377 /**
2378  * i3c_generic_ibi_get_free_slot() - Get a free slot from a generic IBI pool
2379  * @pool: the pool to query an IBI slot on
2380  *
2381  * Search for a free slot in a generic IBI pool.
2382  * The slot should be returned to the pool using i3c_generic_ibi_recycle_slot()
2383  * when it's no longer needed.
2384  *
2385  * Return: a pointer to a free slot, or NULL if there's no free slot available.
2386  */
2387 struct i3c_ibi_slot *
2388 i3c_generic_ibi_get_free_slot(struct i3c_generic_ibi_pool *pool)
2389 {
2390 	struct i3c_generic_ibi_slot *slot;
2391 	unsigned long flags;
2392 
2393 	spin_lock_irqsave(&pool->lock, flags);
2394 	slot = list_first_entry_or_null(&pool->free_slots,
2395 					struct i3c_generic_ibi_slot, node);
2396 	if (slot)
2397 		list_del(&slot->node);
2398 	spin_unlock_irqrestore(&pool->lock, flags);
2399 
2400 	return slot ? &slot->base : NULL;
2401 }
2402 EXPORT_SYMBOL_GPL(i3c_generic_ibi_get_free_slot);
2403 
2404 /**
2405  * i3c_generic_ibi_recycle_slot() - Return a slot to a generic IBI pool
2406  * @pool: the pool to return the IBI slot to
2407  * @s: IBI slot to recycle
2408  *
2409  * Add an IBI slot back to its generic IBI pool. Should be called from the
2410  * master driver struct_master_controller_ops->recycle_ibi() method.
2411  */
2412 void i3c_generic_ibi_recycle_slot(struct i3c_generic_ibi_pool *pool,
2413 				  struct i3c_ibi_slot *s)
2414 {
2415 	struct i3c_generic_ibi_slot *slot;
2416 	unsigned long flags;
2417 
2418 	if (!s)
2419 		return;
2420 
2421 	slot = container_of(s, struct i3c_generic_ibi_slot, base);
2422 	spin_lock_irqsave(&pool->lock, flags);
2423 	list_add_tail(&slot->node, &pool->free_slots);
2424 	spin_unlock_irqrestore(&pool->lock, flags);
2425 }
2426 EXPORT_SYMBOL_GPL(i3c_generic_ibi_recycle_slot);
2427 
2428 static int i3c_master_check_ops(const struct i3c_master_controller_ops *ops)
2429 {
2430 	if (!ops || !ops->bus_init || !ops->priv_xfers ||
2431 	    !ops->send_ccc_cmd || !ops->do_daa || !ops->i2c_xfers)
2432 		return -EINVAL;
2433 
2434 	if (ops->request_ibi &&
2435 	    (!ops->enable_ibi || !ops->disable_ibi || !ops->free_ibi ||
2436 	     !ops->recycle_ibi_slot))
2437 		return -EINVAL;
2438 
2439 	return 0;
2440 }
2441 
2442 /**
2443  * i3c_master_register() - register an I3C master
2444  * @master: master used to send frames on the bus
2445  * @parent: the parent device (the one that provides this I3C master
2446  *	    controller)
2447  * @ops: the master controller operations
2448  * @secondary: true if you are registering a secondary master. Will return
2449  *	       -ENOTSUPP if set to true since secondary masters are not yet
2450  *	       supported
2451  *
2452  * This function takes care of everything for you:
2453  *
2454  * - creates and initializes the I3C bus
2455  * - populates the bus with static I2C devs if @parent->of_node is not
2456  *   NULL
2457  * - registers all I3C devices added by the controller during bus
2458  *   initialization
2459  * - registers the I2C adapter and all I2C devices
2460  *
2461  * Return: 0 in case of success, a negative error code otherwise.
2462  */
2463 int i3c_master_register(struct i3c_master_controller *master,
2464 			struct device *parent,
2465 			const struct i3c_master_controller_ops *ops,
2466 			bool secondary)
2467 {
2468 	unsigned long i2c_scl_rate = I3C_BUS_I2C_FM_PLUS_SCL_RATE;
2469 	struct i3c_bus *i3cbus = i3c_master_get_bus(master);
2470 	enum i3c_bus_mode mode = I3C_BUS_MODE_PURE;
2471 	struct i2c_dev_boardinfo *i2cbi;
2472 	int ret;
2473 
2474 	/* We do not support secondary masters yet. */
2475 	if (secondary)
2476 		return -ENOTSUPP;
2477 
2478 	ret = i3c_master_check_ops(ops);
2479 	if (ret)
2480 		return ret;
2481 
2482 	master->dev.parent = parent;
2483 	master->dev.of_node = of_node_get(parent->of_node);
2484 	master->dev.bus = &i3c_bus_type;
2485 	master->dev.type = &i3c_masterdev_type;
2486 	master->dev.release = i3c_masterdev_release;
2487 	master->ops = ops;
2488 	master->secondary = secondary;
2489 	INIT_LIST_HEAD(&master->boardinfo.i2c);
2490 	INIT_LIST_HEAD(&master->boardinfo.i3c);
2491 
2492 	ret = i3c_bus_init(i3cbus);
2493 	if (ret)
2494 		return ret;
2495 
2496 	device_initialize(&master->dev);
2497 	dev_set_name(&master->dev, "i3c-%d", i3cbus->id);
2498 
2499 	ret = of_populate_i3c_bus(master);
2500 	if (ret)
2501 		goto err_put_dev;
2502 
2503 	list_for_each_entry(i2cbi, &master->boardinfo.i2c, node) {
2504 		switch (i2cbi->lvr & I3C_LVR_I2C_INDEX_MASK) {
2505 		case I3C_LVR_I2C_INDEX(0):
2506 			if (mode < I3C_BUS_MODE_MIXED_FAST)
2507 				mode = I3C_BUS_MODE_MIXED_FAST;
2508 			break;
2509 		case I3C_LVR_I2C_INDEX(1):
2510 			if (mode < I3C_BUS_MODE_MIXED_LIMITED)
2511 				mode = I3C_BUS_MODE_MIXED_LIMITED;
2512 			break;
2513 		case I3C_LVR_I2C_INDEX(2):
2514 			if (mode < I3C_BUS_MODE_MIXED_SLOW)
2515 				mode = I3C_BUS_MODE_MIXED_SLOW;
2516 			break;
2517 		default:
2518 			ret = -EINVAL;
2519 			goto err_put_dev;
2520 		}
2521 
2522 		if (i2cbi->lvr & I3C_LVR_I2C_FM_MODE)
2523 			i2c_scl_rate = I3C_BUS_I2C_FM_SCL_RATE;
2524 	}
2525 
2526 	ret = i3c_bus_set_mode(i3cbus, mode, i2c_scl_rate);
2527 	if (ret)
2528 		goto err_put_dev;
2529 
2530 	master->wq = alloc_workqueue("%s", 0, 0, dev_name(parent));
2531 	if (!master->wq) {
2532 		ret = -ENOMEM;
2533 		goto err_put_dev;
2534 	}
2535 
2536 	ret = i3c_master_bus_init(master);
2537 	if (ret)
2538 		goto err_destroy_wq;
2539 
2540 	ret = device_add(&master->dev);
2541 	if (ret)
2542 		goto err_cleanup_bus;
2543 
2544 	/*
2545 	 * Expose our I3C bus as an I2C adapter so that I2C devices are exposed
2546 	 * through the I2C subsystem.
2547 	 */
2548 	ret = i3c_master_i2c_adapter_init(master);
2549 	if (ret)
2550 		goto err_del_dev;
2551 
2552 	/*
2553 	 * We're done initializing the bus and the controller, we can now
2554 	 * register I3C devices discovered during the initial DAA.
2555 	 */
2556 	master->init_done = true;
2557 	i3c_bus_normaluse_lock(&master->bus);
2558 	i3c_master_register_new_i3c_devs(master);
2559 	i3c_bus_normaluse_unlock(&master->bus);
2560 
2561 	return 0;
2562 
2563 err_del_dev:
2564 	device_del(&master->dev);
2565 
2566 err_cleanup_bus:
2567 	i3c_master_bus_cleanup(master);
2568 
2569 err_destroy_wq:
2570 	destroy_workqueue(master->wq);
2571 
2572 err_put_dev:
2573 	put_device(&master->dev);
2574 
2575 	return ret;
2576 }
2577 EXPORT_SYMBOL_GPL(i3c_master_register);
2578 
2579 /**
2580  * i3c_master_unregister() - unregister an I3C master
2581  * @master: master used to send frames on the bus
2582  *
2583  * Basically undo everything done in i3c_master_register().
2584  *
2585  * Return: 0 in case of success, a negative error code otherwise.
2586  */
2587 int i3c_master_unregister(struct i3c_master_controller *master)
2588 {
2589 	i3c_master_i2c_adapter_cleanup(master);
2590 	i3c_master_unregister_i3c_devs(master);
2591 	i3c_master_bus_cleanup(master);
2592 	device_unregister(&master->dev);
2593 
2594 	return 0;
2595 }
2596 EXPORT_SYMBOL_GPL(i3c_master_unregister);
2597 
2598 int i3c_dev_do_priv_xfers_locked(struct i3c_dev_desc *dev,
2599 				 struct i3c_priv_xfer *xfers,
2600 				 int nxfers)
2601 {
2602 	struct i3c_master_controller *master;
2603 
2604 	if (!dev)
2605 		return -ENOENT;
2606 
2607 	master = i3c_dev_get_master(dev);
2608 	if (!master || !xfers)
2609 		return -EINVAL;
2610 
2611 	if (!master->ops->priv_xfers)
2612 		return -ENOTSUPP;
2613 
2614 	return master->ops->priv_xfers(dev, xfers, nxfers);
2615 }
2616 
2617 int i3c_dev_disable_ibi_locked(struct i3c_dev_desc *dev)
2618 {
2619 	struct i3c_master_controller *master;
2620 	int ret;
2621 
2622 	if (!dev->ibi)
2623 		return -EINVAL;
2624 
2625 	master = i3c_dev_get_master(dev);
2626 	ret = master->ops->disable_ibi(dev);
2627 	if (ret)
2628 		return ret;
2629 
2630 	reinit_completion(&dev->ibi->all_ibis_handled);
2631 	if (atomic_read(&dev->ibi->pending_ibis))
2632 		wait_for_completion(&dev->ibi->all_ibis_handled);
2633 
2634 	dev->ibi->enabled = false;
2635 
2636 	return 0;
2637 }
2638 
2639 int i3c_dev_enable_ibi_locked(struct i3c_dev_desc *dev)
2640 {
2641 	struct i3c_master_controller *master = i3c_dev_get_master(dev);
2642 	int ret;
2643 
2644 	if (!dev->ibi)
2645 		return -EINVAL;
2646 
2647 	ret = master->ops->enable_ibi(dev);
2648 	if (!ret)
2649 		dev->ibi->enabled = true;
2650 
2651 	return ret;
2652 }
2653 
2654 int i3c_dev_request_ibi_locked(struct i3c_dev_desc *dev,
2655 			       const struct i3c_ibi_setup *req)
2656 {
2657 	struct i3c_master_controller *master = i3c_dev_get_master(dev);
2658 	struct i3c_device_ibi_info *ibi;
2659 	int ret;
2660 
2661 	if (!master->ops->request_ibi)
2662 		return -ENOTSUPP;
2663 
2664 	if (dev->ibi)
2665 		return -EBUSY;
2666 
2667 	ibi = kzalloc(sizeof(*ibi), GFP_KERNEL);
2668 	if (!ibi)
2669 		return -ENOMEM;
2670 
2671 	atomic_set(&ibi->pending_ibis, 0);
2672 	init_completion(&ibi->all_ibis_handled);
2673 	ibi->handler = req->handler;
2674 	ibi->max_payload_len = req->max_payload_len;
2675 	ibi->num_slots = req->num_slots;
2676 
2677 	dev->ibi = ibi;
2678 	ret = master->ops->request_ibi(dev, req);
2679 	if (ret) {
2680 		kfree(ibi);
2681 		dev->ibi = NULL;
2682 	}
2683 
2684 	return ret;
2685 }
2686 
2687 void i3c_dev_free_ibi_locked(struct i3c_dev_desc *dev)
2688 {
2689 	struct i3c_master_controller *master = i3c_dev_get_master(dev);
2690 
2691 	if (!dev->ibi)
2692 		return;
2693 
2694 	if (WARN_ON(dev->ibi->enabled))
2695 		WARN_ON(i3c_dev_disable_ibi_locked(dev));
2696 
2697 	master->ops->free_ibi(dev);
2698 	kfree(dev->ibi);
2699 	dev->ibi = NULL;
2700 }
2701 
2702 static int __init i3c_init(void)
2703 {
2704 	return bus_register(&i3c_bus_type);
2705 }
2706 subsys_initcall(i3c_init);
2707 
2708 static void __exit i3c_exit(void)
2709 {
2710 	idr_destroy(&i3c_bus_idr);
2711 	bus_unregister(&i3c_bus_type);
2712 }
2713 module_exit(i3c_exit);
2714 
2715 MODULE_AUTHOR("Boris Brezillon <boris.brezillon@bootlin.com>");
2716 MODULE_DESCRIPTION("I3C core");
2717 MODULE_LICENSE("GPL v2");
2718