xref: /kernel/linux/linux-5.10/drivers/i3c/master.c (revision 8c2ecf20)
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
22static DEFINE_IDR(i3c_bus_idr);
23static 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 */
41static 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 */
55static 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 */
76void 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 */
89void i3c_bus_normaluse_unlock(struct i3c_bus *bus)
90{
91	up_read(&bus->lock);
92}
93
94static struct i3c_master_controller *
95i3c_bus_to_i3c_master(struct i3c_bus *i3cbus)
96{
97	return container_of(i3cbus, struct i3c_master_controller, bus);
98}
99
100static struct i3c_master_controller *dev_to_i3cmaster(struct device *dev)
101{
102	return container_of(dev, struct i3c_master_controller, dev);
103}
104
105static const struct device_type i3c_device_type;
106
107static 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
119static 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
131static 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}
146static DEVICE_ATTR_RO(bcr);
147
148static 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}
163static DEVICE_ATTR_RO(dcr);
164
165static 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}
180static DEVICE_ATTR_RO(pid);
181
182static 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}
197static DEVICE_ATTR_RO(dynamic_address);
198
199static const char * const hdrcap_strings[] = {
200	"hdr-ddr", "hdr-tsp", "hdr-tsl",
201};
202
203static 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
237out:
238	i3c_bus_normaluse_unlock(bus);
239
240	return ret;
241}
242static DEVICE_ATTR_RO(hdrcap);
243
244static 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}
263static DEVICE_ATTR_RO(modalias);
264
265static 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};
274ATTRIBUTE_GROUPS(i3c_device);
275
276static 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
296static const struct device_type i3c_device_type = {
297	.groups	= i3c_device_groups,
298	.uevent = i3c_device_uevent,
299};
300
301static 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
317static 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
325static 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	int ret;
330
331	ret = driver->remove(i3cdev);
332	if (ret)
333		return ret;
334
335	i3c_device_free_ibi(i3cdev);
336
337	return ret;
338}
339
340struct bus_type i3c_bus_type = {
341	.name = "i3c",
342	.match = i3c_device_match,
343	.probe = i3c_device_probe,
344	.remove = i3c_device_remove,
345};
346
347static enum i3c_addr_slot_status
348i3c_bus_get_addr_slot_status(struct i3c_bus *bus, u16 addr)
349{
350	int status, bitpos = addr * 2;
351
352	if (addr > I2C_MAX_ADDR)
353		return I3C_ADDR_SLOT_RSVD;
354
355	status = bus->addrslots[bitpos / BITS_PER_LONG];
356	status >>= bitpos % BITS_PER_LONG;
357
358	return status & I3C_ADDR_SLOT_STATUS_MASK;
359}
360
361static void i3c_bus_set_addr_slot_status(struct i3c_bus *bus, u16 addr,
362					 enum i3c_addr_slot_status status)
363{
364	int bitpos = addr * 2;
365	unsigned long *ptr;
366
367	if (addr > I2C_MAX_ADDR)
368		return;
369
370	ptr = bus->addrslots + (bitpos / BITS_PER_LONG);
371	*ptr &= ~((unsigned long)I3C_ADDR_SLOT_STATUS_MASK <<
372						(bitpos % BITS_PER_LONG));
373	*ptr |= (unsigned long)status << (bitpos % BITS_PER_LONG);
374}
375
376static bool i3c_bus_dev_addr_is_avail(struct i3c_bus *bus, u8 addr)
377{
378	enum i3c_addr_slot_status status;
379
380	status = i3c_bus_get_addr_slot_status(bus, addr);
381
382	return status == I3C_ADDR_SLOT_FREE;
383}
384
385static int i3c_bus_get_free_addr(struct i3c_bus *bus, u8 start_addr)
386{
387	enum i3c_addr_slot_status status;
388	u8 addr;
389
390	for (addr = start_addr; addr < I3C_MAX_ADDR; addr++) {
391		status = i3c_bus_get_addr_slot_status(bus, addr);
392		if (status == I3C_ADDR_SLOT_FREE)
393			return addr;
394	}
395
396	return -ENOMEM;
397}
398
399static void i3c_bus_init_addrslots(struct i3c_bus *bus)
400{
401	int i;
402
403	/* Addresses 0 to 7 are reserved. */
404	for (i = 0; i < 8; i++)
405		i3c_bus_set_addr_slot_status(bus, i, I3C_ADDR_SLOT_RSVD);
406
407	/*
408	 * Reserve broadcast address and all addresses that might collide
409	 * with the broadcast address when facing a single bit error.
410	 */
411	i3c_bus_set_addr_slot_status(bus, I3C_BROADCAST_ADDR,
412				     I3C_ADDR_SLOT_RSVD);
413	for (i = 0; i < 7; i++)
414		i3c_bus_set_addr_slot_status(bus, I3C_BROADCAST_ADDR ^ BIT(i),
415					     I3C_ADDR_SLOT_RSVD);
416}
417
418static void i3c_bus_cleanup(struct i3c_bus *i3cbus)
419{
420	mutex_lock(&i3c_core_lock);
421	idr_remove(&i3c_bus_idr, i3cbus->id);
422	mutex_unlock(&i3c_core_lock);
423}
424
425static int i3c_bus_init(struct i3c_bus *i3cbus)
426{
427	int ret;
428
429	init_rwsem(&i3cbus->lock);
430	INIT_LIST_HEAD(&i3cbus->devs.i2c);
431	INIT_LIST_HEAD(&i3cbus->devs.i3c);
432	i3c_bus_init_addrslots(i3cbus);
433	i3cbus->mode = I3C_BUS_MODE_PURE;
434
435	mutex_lock(&i3c_core_lock);
436	ret = idr_alloc(&i3c_bus_idr, i3cbus, 0, 0, GFP_KERNEL);
437	mutex_unlock(&i3c_core_lock);
438
439	if (ret < 0)
440		return ret;
441
442	i3cbus->id = ret;
443
444	return 0;
445}
446
447static const char * const i3c_bus_mode_strings[] = {
448	[I3C_BUS_MODE_PURE] = "pure",
449	[I3C_BUS_MODE_MIXED_FAST] = "mixed-fast",
450	[I3C_BUS_MODE_MIXED_LIMITED] = "mixed-limited",
451	[I3C_BUS_MODE_MIXED_SLOW] = "mixed-slow",
452};
453
454static ssize_t mode_show(struct device *dev,
455			 struct device_attribute *da,
456			 char *buf)
457{
458	struct i3c_bus *i3cbus = dev_to_i3cbus(dev);
459	ssize_t ret;
460
461	i3c_bus_normaluse_lock(i3cbus);
462	if (i3cbus->mode < 0 ||
463	    i3cbus->mode >= ARRAY_SIZE(i3c_bus_mode_strings) ||
464	    !i3c_bus_mode_strings[i3cbus->mode])
465		ret = sprintf(buf, "unknown\n");
466	else
467		ret = sprintf(buf, "%s\n", i3c_bus_mode_strings[i3cbus->mode]);
468	i3c_bus_normaluse_unlock(i3cbus);
469
470	return ret;
471}
472static DEVICE_ATTR_RO(mode);
473
474static ssize_t current_master_show(struct device *dev,
475				   struct device_attribute *da,
476				   char *buf)
477{
478	struct i3c_bus *i3cbus = dev_to_i3cbus(dev);
479	ssize_t ret;
480
481	i3c_bus_normaluse_lock(i3cbus);
482	ret = sprintf(buf, "%d-%llx\n", i3cbus->id,
483		      i3cbus->cur_master->info.pid);
484	i3c_bus_normaluse_unlock(i3cbus);
485
486	return ret;
487}
488static DEVICE_ATTR_RO(current_master);
489
490static ssize_t i3c_scl_frequency_show(struct device *dev,
491				      struct device_attribute *da,
492				      char *buf)
493{
494	struct i3c_bus *i3cbus = dev_to_i3cbus(dev);
495	ssize_t ret;
496
497	i3c_bus_normaluse_lock(i3cbus);
498	ret = sprintf(buf, "%ld\n", i3cbus->scl_rate.i3c);
499	i3c_bus_normaluse_unlock(i3cbus);
500
501	return ret;
502}
503static DEVICE_ATTR_RO(i3c_scl_frequency);
504
505static ssize_t i2c_scl_frequency_show(struct device *dev,
506				      struct device_attribute *da,
507				      char *buf)
508{
509	struct i3c_bus *i3cbus = dev_to_i3cbus(dev);
510	ssize_t ret;
511
512	i3c_bus_normaluse_lock(i3cbus);
513	ret = sprintf(buf, "%ld\n", i3cbus->scl_rate.i2c);
514	i3c_bus_normaluse_unlock(i3cbus);
515
516	return ret;
517}
518static DEVICE_ATTR_RO(i2c_scl_frequency);
519
520static struct attribute *i3c_masterdev_attrs[] = {
521	&dev_attr_mode.attr,
522	&dev_attr_current_master.attr,
523	&dev_attr_i3c_scl_frequency.attr,
524	&dev_attr_i2c_scl_frequency.attr,
525	&dev_attr_bcr.attr,
526	&dev_attr_dcr.attr,
527	&dev_attr_pid.attr,
528	&dev_attr_dynamic_address.attr,
529	&dev_attr_hdrcap.attr,
530	NULL,
531};
532ATTRIBUTE_GROUPS(i3c_masterdev);
533
534static void i3c_masterdev_release(struct device *dev)
535{
536	struct i3c_master_controller *master = dev_to_i3cmaster(dev);
537	struct i3c_bus *bus = dev_to_i3cbus(dev);
538
539	if (master->wq)
540		destroy_workqueue(master->wq);
541
542	WARN_ON(!list_empty(&bus->devs.i2c) || !list_empty(&bus->devs.i3c));
543	i3c_bus_cleanup(bus);
544
545	of_node_put(dev->of_node);
546}
547
548static const struct device_type i3c_masterdev_type = {
549	.groups	= i3c_masterdev_groups,
550};
551
552static int i3c_bus_set_mode(struct i3c_bus *i3cbus, enum i3c_bus_mode mode,
553			    unsigned long max_i2c_scl_rate)
554{
555	struct i3c_master_controller *master = i3c_bus_to_i3c_master(i3cbus);
556
557	i3cbus->mode = mode;
558
559	switch (i3cbus->mode) {
560	case I3C_BUS_MODE_PURE:
561		if (!i3cbus->scl_rate.i3c)
562			i3cbus->scl_rate.i3c = I3C_BUS_TYP_I3C_SCL_RATE;
563		break;
564	case I3C_BUS_MODE_MIXED_FAST:
565	case I3C_BUS_MODE_MIXED_LIMITED:
566		if (!i3cbus->scl_rate.i3c)
567			i3cbus->scl_rate.i3c = I3C_BUS_TYP_I3C_SCL_RATE;
568		if (!i3cbus->scl_rate.i2c)
569			i3cbus->scl_rate.i2c = max_i2c_scl_rate;
570		break;
571	case I3C_BUS_MODE_MIXED_SLOW:
572		if (!i3cbus->scl_rate.i2c)
573			i3cbus->scl_rate.i2c = max_i2c_scl_rate;
574		if (!i3cbus->scl_rate.i3c ||
575		    i3cbus->scl_rate.i3c > i3cbus->scl_rate.i2c)
576			i3cbus->scl_rate.i3c = i3cbus->scl_rate.i2c;
577		break;
578	default:
579		return -EINVAL;
580	}
581
582	dev_dbg(&master->dev, "i2c-scl = %ld Hz i3c-scl = %ld Hz\n",
583		i3cbus->scl_rate.i2c, i3cbus->scl_rate.i3c);
584
585	/*
586	 * I3C/I2C frequency may have been overridden, check that user-provided
587	 * values are not exceeding max possible frequency.
588	 */
589	if (i3cbus->scl_rate.i3c > I3C_BUS_MAX_I3C_SCL_RATE ||
590	    i3cbus->scl_rate.i2c > I3C_BUS_I2C_FM_PLUS_SCL_RATE)
591		return -EINVAL;
592
593	return 0;
594}
595
596static struct i3c_master_controller *
597i2c_adapter_to_i3c_master(struct i2c_adapter *adap)
598{
599	return container_of(adap, struct i3c_master_controller, i2c);
600}
601
602static struct i2c_adapter *
603i3c_master_to_i2c_adapter(struct i3c_master_controller *master)
604{
605	return &master->i2c;
606}
607
608static void i3c_master_free_i2c_dev(struct i2c_dev_desc *dev)
609{
610	kfree(dev);
611}
612
613static struct i2c_dev_desc *
614i3c_master_alloc_i2c_dev(struct i3c_master_controller *master,
615			 const struct i2c_dev_boardinfo *boardinfo)
616{
617	struct i2c_dev_desc *dev;
618
619	dev = kzalloc(sizeof(*dev), GFP_KERNEL);
620	if (!dev)
621		return ERR_PTR(-ENOMEM);
622
623	dev->common.master = master;
624	dev->boardinfo = boardinfo;
625	dev->addr = boardinfo->base.addr;
626	dev->lvr = boardinfo->lvr;
627
628	return dev;
629}
630
631static void *i3c_ccc_cmd_dest_init(struct i3c_ccc_cmd_dest *dest, u8 addr,
632				   u16 payloadlen)
633{
634	dest->addr = addr;
635	dest->payload.len = payloadlen;
636	if (payloadlen)
637		dest->payload.data = kzalloc(payloadlen, GFP_KERNEL);
638	else
639		dest->payload.data = NULL;
640
641	return dest->payload.data;
642}
643
644static void i3c_ccc_cmd_dest_cleanup(struct i3c_ccc_cmd_dest *dest)
645{
646	kfree(dest->payload.data);
647}
648
649static void i3c_ccc_cmd_init(struct i3c_ccc_cmd *cmd, bool rnw, u8 id,
650			     struct i3c_ccc_cmd_dest *dests,
651			     unsigned int ndests)
652{
653	cmd->rnw = rnw ? 1 : 0;
654	cmd->id = id;
655	cmd->dests = dests;
656	cmd->ndests = ndests;
657	cmd->err = I3C_ERROR_UNKNOWN;
658}
659
660static int i3c_master_send_ccc_cmd_locked(struct i3c_master_controller *master,
661					  struct i3c_ccc_cmd *cmd)
662{
663	int ret;
664
665	if (!cmd || !master)
666		return -EINVAL;
667
668	if (WARN_ON(master->init_done &&
669		    !rwsem_is_locked(&master->bus.lock)))
670		return -EINVAL;
671
672	if (!master->ops->send_ccc_cmd)
673		return -ENOTSUPP;
674
675	if ((cmd->id & I3C_CCC_DIRECT) && (!cmd->dests || !cmd->ndests))
676		return -EINVAL;
677
678	if (master->ops->supports_ccc_cmd &&
679	    !master->ops->supports_ccc_cmd(master, cmd))
680		return -ENOTSUPP;
681
682	ret = master->ops->send_ccc_cmd(master, cmd);
683	if (ret) {
684		if (cmd->err != I3C_ERROR_UNKNOWN)
685			return cmd->err;
686
687		return ret;
688	}
689
690	return 0;
691}
692
693static struct i2c_dev_desc *
694i3c_master_find_i2c_dev_by_addr(const struct i3c_master_controller *master,
695				u16 addr)
696{
697	struct i2c_dev_desc *dev;
698
699	i3c_bus_for_each_i2cdev(&master->bus, dev) {
700		if (dev->boardinfo->base.addr == addr)
701			return dev;
702	}
703
704	return NULL;
705}
706
707/**
708 * i3c_master_get_free_addr() - get a free address on the bus
709 * @master: I3C master object
710 * @start_addr: where to start searching
711 *
712 * This function must be called with the bus lock held in write mode.
713 *
714 * Return: the first free address starting at @start_addr (included) or -ENOMEM
715 * if there's no more address available.
716 */
717int i3c_master_get_free_addr(struct i3c_master_controller *master,
718			     u8 start_addr)
719{
720	return i3c_bus_get_free_addr(&master->bus, start_addr);
721}
722EXPORT_SYMBOL_GPL(i3c_master_get_free_addr);
723
724static void i3c_device_release(struct device *dev)
725{
726	struct i3c_device *i3cdev = dev_to_i3cdev(dev);
727
728	WARN_ON(i3cdev->desc);
729
730	of_node_put(i3cdev->dev.of_node);
731	kfree(i3cdev);
732}
733
734static void i3c_master_free_i3c_dev(struct i3c_dev_desc *dev)
735{
736	kfree(dev);
737}
738
739static struct i3c_dev_desc *
740i3c_master_alloc_i3c_dev(struct i3c_master_controller *master,
741			 const struct i3c_device_info *info)
742{
743	struct i3c_dev_desc *dev;
744
745	dev = kzalloc(sizeof(*dev), GFP_KERNEL);
746	if (!dev)
747		return ERR_PTR(-ENOMEM);
748
749	dev->common.master = master;
750	dev->info = *info;
751	mutex_init(&dev->ibi_lock);
752
753	return dev;
754}
755
756static int i3c_master_rstdaa_locked(struct i3c_master_controller *master,
757				    u8 addr)
758{
759	enum i3c_addr_slot_status addrstat;
760	struct i3c_ccc_cmd_dest dest;
761	struct i3c_ccc_cmd cmd;
762	int ret;
763
764	if (!master)
765		return -EINVAL;
766
767	addrstat = i3c_bus_get_addr_slot_status(&master->bus, addr);
768	if (addr != I3C_BROADCAST_ADDR && addrstat != I3C_ADDR_SLOT_I3C_DEV)
769		return -EINVAL;
770
771	i3c_ccc_cmd_dest_init(&dest, addr, 0);
772	i3c_ccc_cmd_init(&cmd, false,
773			 I3C_CCC_RSTDAA(addr == I3C_BROADCAST_ADDR),
774			 &dest, 1);
775	ret = i3c_master_send_ccc_cmd_locked(master, &cmd);
776	i3c_ccc_cmd_dest_cleanup(&dest);
777
778	return ret;
779}
780
781/**
782 * i3c_master_entdaa_locked() - start a DAA (Dynamic Address Assignment)
783 *				procedure
784 * @master: master used to send frames on the bus
785 *
786 * Send a ENTDAA CCC command to start a DAA procedure.
787 *
788 * Note that this function only sends the ENTDAA CCC command, all the logic
789 * behind dynamic address assignment has to be handled in the I3C master
790 * driver.
791 *
792 * This function must be called with the bus lock held in write mode.
793 *
794 * Return: 0 in case of success, a positive I3C error code if the error is
795 * one of the official Mx error codes, and a negative error code otherwise.
796 */
797int i3c_master_entdaa_locked(struct i3c_master_controller *master)
798{
799	struct i3c_ccc_cmd_dest dest;
800	struct i3c_ccc_cmd cmd;
801	int ret;
802
803	i3c_ccc_cmd_dest_init(&dest, I3C_BROADCAST_ADDR, 0);
804	i3c_ccc_cmd_init(&cmd, false, I3C_CCC_ENTDAA, &dest, 1);
805	ret = i3c_master_send_ccc_cmd_locked(master, &cmd);
806	i3c_ccc_cmd_dest_cleanup(&dest);
807
808	return ret;
809}
810EXPORT_SYMBOL_GPL(i3c_master_entdaa_locked);
811
812static int i3c_master_enec_disec_locked(struct i3c_master_controller *master,
813					u8 addr, bool enable, u8 evts)
814{
815	struct i3c_ccc_events *events;
816	struct i3c_ccc_cmd_dest dest;
817	struct i3c_ccc_cmd cmd;
818	int ret;
819
820	events = i3c_ccc_cmd_dest_init(&dest, addr, sizeof(*events));
821	if (!events)
822		return -ENOMEM;
823
824	events->events = evts;
825	i3c_ccc_cmd_init(&cmd, false,
826			 enable ?
827			 I3C_CCC_ENEC(addr == I3C_BROADCAST_ADDR) :
828			 I3C_CCC_DISEC(addr == I3C_BROADCAST_ADDR),
829			 &dest, 1);
830	ret = i3c_master_send_ccc_cmd_locked(master, &cmd);
831	i3c_ccc_cmd_dest_cleanup(&dest);
832
833	return ret;
834}
835
836/**
837 * i3c_master_disec_locked() - send a DISEC CCC command
838 * @master: master used to send frames on the bus
839 * @addr: a valid I3C slave address or %I3C_BROADCAST_ADDR
840 * @evts: events to disable
841 *
842 * Send a DISEC CCC command to disable some or all events coming from a
843 * specific slave, or all devices if @addr is %I3C_BROADCAST_ADDR.
844 *
845 * This function must be called with the bus lock held in write mode.
846 *
847 * Return: 0 in case of success, a positive I3C error code if the error is
848 * one of the official Mx error codes, and a negative error code otherwise.
849 */
850int i3c_master_disec_locked(struct i3c_master_controller *master, u8 addr,
851			    u8 evts)
852{
853	return i3c_master_enec_disec_locked(master, addr, false, evts);
854}
855EXPORT_SYMBOL_GPL(i3c_master_disec_locked);
856
857/**
858 * i3c_master_enec_locked() - send an ENEC CCC command
859 * @master: master used to send frames on the bus
860 * @addr: a valid I3C slave address or %I3C_BROADCAST_ADDR
861 * @evts: events to disable
862 *
863 * Sends an ENEC CCC command to enable some or all events coming from a
864 * specific slave, or all devices if @addr is %I3C_BROADCAST_ADDR.
865 *
866 * This function must be called with the bus lock held in write mode.
867 *
868 * Return: 0 in case of success, a positive I3C error code if the error is
869 * one of the official Mx error codes, and a negative error code otherwise.
870 */
871int i3c_master_enec_locked(struct i3c_master_controller *master, u8 addr,
872			   u8 evts)
873{
874	return i3c_master_enec_disec_locked(master, addr, true, evts);
875}
876EXPORT_SYMBOL_GPL(i3c_master_enec_locked);
877
878/**
879 * i3c_master_defslvs_locked() - send a DEFSLVS CCC command
880 * @master: master used to send frames on the bus
881 *
882 * Send a DEFSLVS CCC command containing all the devices known to the @master.
883 * This is useful when you have secondary masters on the bus to propagate
884 * device information.
885 *
886 * This should be called after all I3C devices have been discovered (in other
887 * words, after the DAA procedure has finished) and instantiated in
888 * &i3c_master_controller_ops->bus_init().
889 * It should also be called if a master ACKed an Hot-Join request and assigned
890 * a dynamic address to the device joining the bus.
891 *
892 * This function must be called with the bus lock held in write mode.
893 *
894 * Return: 0 in case of success, a positive I3C error code if the error is
895 * one of the official Mx error codes, and a negative error code otherwise.
896 */
897int i3c_master_defslvs_locked(struct i3c_master_controller *master)
898{
899	struct i3c_ccc_defslvs *defslvs;
900	struct i3c_ccc_dev_desc *desc;
901	struct i3c_ccc_cmd_dest dest;
902	struct i3c_dev_desc *i3cdev;
903	struct i2c_dev_desc *i2cdev;
904	struct i3c_ccc_cmd cmd;
905	struct i3c_bus *bus;
906	bool send = false;
907	int ndevs = 0, ret;
908
909	if (!master)
910		return -EINVAL;
911
912	bus = i3c_master_get_bus(master);
913	i3c_bus_for_each_i3cdev(bus, i3cdev) {
914		ndevs++;
915
916		if (i3cdev == master->this)
917			continue;
918
919		if (I3C_BCR_DEVICE_ROLE(i3cdev->info.bcr) ==
920		    I3C_BCR_I3C_MASTER)
921			send = true;
922	}
923
924	/* No other master on the bus, skip DEFSLVS. */
925	if (!send)
926		return 0;
927
928	i3c_bus_for_each_i2cdev(bus, i2cdev)
929		ndevs++;
930
931	defslvs = i3c_ccc_cmd_dest_init(&dest, I3C_BROADCAST_ADDR,
932					struct_size(defslvs, slaves,
933						    ndevs - 1));
934	if (!defslvs)
935		return -ENOMEM;
936
937	defslvs->count = ndevs;
938	defslvs->master.bcr = master->this->info.bcr;
939	defslvs->master.dcr = master->this->info.dcr;
940	defslvs->master.dyn_addr = master->this->info.dyn_addr << 1;
941	defslvs->master.static_addr = I3C_BROADCAST_ADDR << 1;
942
943	desc = defslvs->slaves;
944	i3c_bus_for_each_i2cdev(bus, i2cdev) {
945		desc->lvr = i2cdev->lvr;
946		desc->static_addr = i2cdev->addr << 1;
947		desc++;
948	}
949
950	i3c_bus_for_each_i3cdev(bus, i3cdev) {
951		/* Skip the I3C dev representing this master. */
952		if (i3cdev == master->this)
953			continue;
954
955		desc->bcr = i3cdev->info.bcr;
956		desc->dcr = i3cdev->info.dcr;
957		desc->dyn_addr = i3cdev->info.dyn_addr << 1;
958		desc->static_addr = i3cdev->info.static_addr << 1;
959		desc++;
960	}
961
962	i3c_ccc_cmd_init(&cmd, false, I3C_CCC_DEFSLVS, &dest, 1);
963	ret = i3c_master_send_ccc_cmd_locked(master, &cmd);
964	i3c_ccc_cmd_dest_cleanup(&dest);
965
966	return ret;
967}
968EXPORT_SYMBOL_GPL(i3c_master_defslvs_locked);
969
970static int i3c_master_setda_locked(struct i3c_master_controller *master,
971				   u8 oldaddr, u8 newaddr, bool setdasa)
972{
973	struct i3c_ccc_cmd_dest dest;
974	struct i3c_ccc_setda *setda;
975	struct i3c_ccc_cmd cmd;
976	int ret;
977
978	if (!oldaddr || !newaddr)
979		return -EINVAL;
980
981	setda = i3c_ccc_cmd_dest_init(&dest, oldaddr, sizeof(*setda));
982	if (!setda)
983		return -ENOMEM;
984
985	setda->addr = newaddr << 1;
986	i3c_ccc_cmd_init(&cmd, false,
987			 setdasa ? I3C_CCC_SETDASA : I3C_CCC_SETNEWDA,
988			 &dest, 1);
989	ret = i3c_master_send_ccc_cmd_locked(master, &cmd);
990	i3c_ccc_cmd_dest_cleanup(&dest);
991
992	return ret;
993}
994
995static int i3c_master_setdasa_locked(struct i3c_master_controller *master,
996				     u8 static_addr, u8 dyn_addr)
997{
998	return i3c_master_setda_locked(master, static_addr, dyn_addr, true);
999}
1000
1001static int i3c_master_setnewda_locked(struct i3c_master_controller *master,
1002				      u8 oldaddr, u8 newaddr)
1003{
1004	return i3c_master_setda_locked(master, oldaddr, newaddr, false);
1005}
1006
1007static int i3c_master_getmrl_locked(struct i3c_master_controller *master,
1008				    struct i3c_device_info *info)
1009{
1010	struct i3c_ccc_cmd_dest dest;
1011	struct i3c_ccc_mrl *mrl;
1012	struct i3c_ccc_cmd cmd;
1013	int ret;
1014
1015	mrl = i3c_ccc_cmd_dest_init(&dest, info->dyn_addr, sizeof(*mrl));
1016	if (!mrl)
1017		return -ENOMEM;
1018
1019	/*
1020	 * When the device does not have IBI payload GETMRL only returns 2
1021	 * bytes of data.
1022	 */
1023	if (!(info->bcr & I3C_BCR_IBI_PAYLOAD))
1024		dest.payload.len -= 1;
1025
1026	i3c_ccc_cmd_init(&cmd, true, I3C_CCC_GETMRL, &dest, 1);
1027	ret = i3c_master_send_ccc_cmd_locked(master, &cmd);
1028	if (ret)
1029		goto out;
1030
1031	switch (dest.payload.len) {
1032	case 3:
1033		info->max_ibi_len = mrl->ibi_len;
1034		fallthrough;
1035	case 2:
1036		info->max_read_len = be16_to_cpu(mrl->read_len);
1037		break;
1038	default:
1039		ret = -EIO;
1040		goto out;
1041	}
1042
1043out:
1044	i3c_ccc_cmd_dest_cleanup(&dest);
1045
1046	return ret;
1047}
1048
1049static int i3c_master_getmwl_locked(struct i3c_master_controller *master,
1050				    struct i3c_device_info *info)
1051{
1052	struct i3c_ccc_cmd_dest dest;
1053	struct i3c_ccc_mwl *mwl;
1054	struct i3c_ccc_cmd cmd;
1055	int ret;
1056
1057	mwl = i3c_ccc_cmd_dest_init(&dest, info->dyn_addr, sizeof(*mwl));
1058	if (!mwl)
1059		return -ENOMEM;
1060
1061	i3c_ccc_cmd_init(&cmd, true, I3C_CCC_GETMWL, &dest, 1);
1062	ret = i3c_master_send_ccc_cmd_locked(master, &cmd);
1063	if (ret)
1064		goto out;
1065
1066	if (dest.payload.len != sizeof(*mwl)) {
1067		ret = -EIO;
1068		goto out;
1069	}
1070
1071	info->max_write_len = be16_to_cpu(mwl->len);
1072
1073out:
1074	i3c_ccc_cmd_dest_cleanup(&dest);
1075
1076	return ret;
1077}
1078
1079static int i3c_master_getmxds_locked(struct i3c_master_controller *master,
1080				     struct i3c_device_info *info)
1081{
1082	struct i3c_ccc_getmxds *getmaxds;
1083	struct i3c_ccc_cmd_dest dest;
1084	struct i3c_ccc_cmd cmd;
1085	int ret;
1086
1087	getmaxds = i3c_ccc_cmd_dest_init(&dest, info->dyn_addr,
1088					 sizeof(*getmaxds));
1089	if (!getmaxds)
1090		return -ENOMEM;
1091
1092	i3c_ccc_cmd_init(&cmd, true, I3C_CCC_GETMXDS, &dest, 1);
1093	ret = i3c_master_send_ccc_cmd_locked(master, &cmd);
1094	if (ret)
1095		goto out;
1096
1097	if (dest.payload.len != 2 && dest.payload.len != 5) {
1098		ret = -EIO;
1099		goto out;
1100	}
1101
1102	info->max_read_ds = getmaxds->maxrd;
1103	info->max_write_ds = getmaxds->maxwr;
1104	if (dest.payload.len == 5)
1105		info->max_read_turnaround = getmaxds->maxrdturn[0] |
1106					    ((u32)getmaxds->maxrdturn[1] << 8) |
1107					    ((u32)getmaxds->maxrdturn[2] << 16);
1108
1109out:
1110	i3c_ccc_cmd_dest_cleanup(&dest);
1111
1112	return ret;
1113}
1114
1115static int i3c_master_gethdrcap_locked(struct i3c_master_controller *master,
1116				       struct i3c_device_info *info)
1117{
1118	struct i3c_ccc_gethdrcap *gethdrcap;
1119	struct i3c_ccc_cmd_dest dest;
1120	struct i3c_ccc_cmd cmd;
1121	int ret;
1122
1123	gethdrcap = i3c_ccc_cmd_dest_init(&dest, info->dyn_addr,
1124					  sizeof(*gethdrcap));
1125	if (!gethdrcap)
1126		return -ENOMEM;
1127
1128	i3c_ccc_cmd_init(&cmd, true, I3C_CCC_GETHDRCAP, &dest, 1);
1129	ret = i3c_master_send_ccc_cmd_locked(master, &cmd);
1130	if (ret)
1131		goto out;
1132
1133	if (dest.payload.len != 1) {
1134		ret = -EIO;
1135		goto out;
1136	}
1137
1138	info->hdr_cap = gethdrcap->modes;
1139
1140out:
1141	i3c_ccc_cmd_dest_cleanup(&dest);
1142
1143	return ret;
1144}
1145
1146static int i3c_master_getpid_locked(struct i3c_master_controller *master,
1147				    struct i3c_device_info *info)
1148{
1149	struct i3c_ccc_getpid *getpid;
1150	struct i3c_ccc_cmd_dest dest;
1151	struct i3c_ccc_cmd cmd;
1152	int ret, i;
1153
1154	getpid = i3c_ccc_cmd_dest_init(&dest, info->dyn_addr, sizeof(*getpid));
1155	if (!getpid)
1156		return -ENOMEM;
1157
1158	i3c_ccc_cmd_init(&cmd, true, I3C_CCC_GETPID, &dest, 1);
1159	ret = i3c_master_send_ccc_cmd_locked(master, &cmd);
1160	if (ret)
1161		goto out;
1162
1163	info->pid = 0;
1164	for (i = 0; i < sizeof(getpid->pid); i++) {
1165		int sft = (sizeof(getpid->pid) - i - 1) * 8;
1166
1167		info->pid |= (u64)getpid->pid[i] << sft;
1168	}
1169
1170out:
1171	i3c_ccc_cmd_dest_cleanup(&dest);
1172
1173	return ret;
1174}
1175
1176static int i3c_master_getbcr_locked(struct i3c_master_controller *master,
1177				    struct i3c_device_info *info)
1178{
1179	struct i3c_ccc_getbcr *getbcr;
1180	struct i3c_ccc_cmd_dest dest;
1181	struct i3c_ccc_cmd cmd;
1182	int ret;
1183
1184	getbcr = i3c_ccc_cmd_dest_init(&dest, info->dyn_addr, sizeof(*getbcr));
1185	if (!getbcr)
1186		return -ENOMEM;
1187
1188	i3c_ccc_cmd_init(&cmd, true, I3C_CCC_GETBCR, &dest, 1);
1189	ret = i3c_master_send_ccc_cmd_locked(master, &cmd);
1190	if (ret)
1191		goto out;
1192
1193	info->bcr = getbcr->bcr;
1194
1195out:
1196	i3c_ccc_cmd_dest_cleanup(&dest);
1197
1198	return ret;
1199}
1200
1201static int i3c_master_getdcr_locked(struct i3c_master_controller *master,
1202				    struct i3c_device_info *info)
1203{
1204	struct i3c_ccc_getdcr *getdcr;
1205	struct i3c_ccc_cmd_dest dest;
1206	struct i3c_ccc_cmd cmd;
1207	int ret;
1208
1209	getdcr = i3c_ccc_cmd_dest_init(&dest, info->dyn_addr, sizeof(*getdcr));
1210	if (!getdcr)
1211		return -ENOMEM;
1212
1213	i3c_ccc_cmd_init(&cmd, true, I3C_CCC_GETDCR, &dest, 1);
1214	ret = i3c_master_send_ccc_cmd_locked(master, &cmd);
1215	if (ret)
1216		goto out;
1217
1218	info->dcr = getdcr->dcr;
1219
1220out:
1221	i3c_ccc_cmd_dest_cleanup(&dest);
1222
1223	return ret;
1224}
1225
1226static int i3c_master_retrieve_dev_info(struct i3c_dev_desc *dev)
1227{
1228	struct i3c_master_controller *master = i3c_dev_get_master(dev);
1229	enum i3c_addr_slot_status slot_status;
1230	int ret;
1231
1232	if (!dev->info.dyn_addr)
1233		return -EINVAL;
1234
1235	slot_status = i3c_bus_get_addr_slot_status(&master->bus,
1236						   dev->info.dyn_addr);
1237	if (slot_status == I3C_ADDR_SLOT_RSVD ||
1238	    slot_status == I3C_ADDR_SLOT_I2C_DEV)
1239		return -EINVAL;
1240
1241	ret = i3c_master_getpid_locked(master, &dev->info);
1242	if (ret)
1243		return ret;
1244
1245	ret = i3c_master_getbcr_locked(master, &dev->info);
1246	if (ret)
1247		return ret;
1248
1249	ret = i3c_master_getdcr_locked(master, &dev->info);
1250	if (ret)
1251		return ret;
1252
1253	if (dev->info.bcr & I3C_BCR_MAX_DATA_SPEED_LIM) {
1254		ret = i3c_master_getmxds_locked(master, &dev->info);
1255		if (ret)
1256			return ret;
1257	}
1258
1259	if (dev->info.bcr & I3C_BCR_IBI_PAYLOAD)
1260		dev->info.max_ibi_len = 1;
1261
1262	i3c_master_getmrl_locked(master, &dev->info);
1263	i3c_master_getmwl_locked(master, &dev->info);
1264
1265	if (dev->info.bcr & I3C_BCR_HDR_CAP) {
1266		ret = i3c_master_gethdrcap_locked(master, &dev->info);
1267		if (ret)
1268			return ret;
1269	}
1270
1271	return 0;
1272}
1273
1274static void i3c_master_put_i3c_addrs(struct i3c_dev_desc *dev)
1275{
1276	struct i3c_master_controller *master = i3c_dev_get_master(dev);
1277
1278	if (dev->info.static_addr)
1279		i3c_bus_set_addr_slot_status(&master->bus,
1280					     dev->info.static_addr,
1281					     I3C_ADDR_SLOT_FREE);
1282
1283	if (dev->info.dyn_addr)
1284		i3c_bus_set_addr_slot_status(&master->bus, dev->info.dyn_addr,
1285					     I3C_ADDR_SLOT_FREE);
1286
1287	if (dev->boardinfo && dev->boardinfo->init_dyn_addr)
1288		i3c_bus_set_addr_slot_status(&master->bus, dev->info.dyn_addr,
1289					     I3C_ADDR_SLOT_FREE);
1290}
1291
1292static int i3c_master_get_i3c_addrs(struct i3c_dev_desc *dev)
1293{
1294	struct i3c_master_controller *master = i3c_dev_get_master(dev);
1295	enum i3c_addr_slot_status status;
1296
1297	if (!dev->info.static_addr && !dev->info.dyn_addr)
1298		return 0;
1299
1300	if (dev->info.static_addr) {
1301		status = i3c_bus_get_addr_slot_status(&master->bus,
1302						      dev->info.static_addr);
1303		if (status != I3C_ADDR_SLOT_FREE)
1304			return -EBUSY;
1305
1306		i3c_bus_set_addr_slot_status(&master->bus,
1307					     dev->info.static_addr,
1308					     I3C_ADDR_SLOT_I3C_DEV);
1309	}
1310
1311	/*
1312	 * ->init_dyn_addr should have been reserved before that, so, if we're
1313	 * trying to apply a pre-reserved dynamic address, we should not try
1314	 * to reserve the address slot a second time.
1315	 */
1316	if (dev->info.dyn_addr &&
1317	    (!dev->boardinfo ||
1318	     dev->boardinfo->init_dyn_addr != dev->info.dyn_addr)) {
1319		status = i3c_bus_get_addr_slot_status(&master->bus,
1320						      dev->info.dyn_addr);
1321		if (status != I3C_ADDR_SLOT_FREE)
1322			goto err_release_static_addr;
1323
1324		i3c_bus_set_addr_slot_status(&master->bus, dev->info.dyn_addr,
1325					     I3C_ADDR_SLOT_I3C_DEV);
1326	}
1327
1328	return 0;
1329
1330err_release_static_addr:
1331	if (dev->info.static_addr)
1332		i3c_bus_set_addr_slot_status(&master->bus,
1333					     dev->info.static_addr,
1334					     I3C_ADDR_SLOT_FREE);
1335
1336	return -EBUSY;
1337}
1338
1339static int i3c_master_attach_i3c_dev(struct i3c_master_controller *master,
1340				     struct i3c_dev_desc *dev)
1341{
1342	int ret;
1343
1344	/*
1345	 * We don't attach devices to the controller until they are
1346	 * addressable on the bus.
1347	 */
1348	if (!dev->info.static_addr && !dev->info.dyn_addr)
1349		return 0;
1350
1351	ret = i3c_master_get_i3c_addrs(dev);
1352	if (ret)
1353		return ret;
1354
1355	/* Do not attach the master device itself. */
1356	if (master->this != dev && master->ops->attach_i3c_dev) {
1357		ret = master->ops->attach_i3c_dev(dev);
1358		if (ret) {
1359			i3c_master_put_i3c_addrs(dev);
1360			return ret;
1361		}
1362	}
1363
1364	list_add_tail(&dev->common.node, &master->bus.devs.i3c);
1365
1366	return 0;
1367}
1368
1369static int i3c_master_reattach_i3c_dev(struct i3c_dev_desc *dev,
1370				       u8 old_dyn_addr)
1371{
1372	struct i3c_master_controller *master = i3c_dev_get_master(dev);
1373	enum i3c_addr_slot_status status;
1374	int ret;
1375
1376	if (dev->info.dyn_addr != old_dyn_addr &&
1377	    (!dev->boardinfo ||
1378	     dev->info.dyn_addr != dev->boardinfo->init_dyn_addr)) {
1379		status = i3c_bus_get_addr_slot_status(&master->bus,
1380						      dev->info.dyn_addr);
1381		if (status != I3C_ADDR_SLOT_FREE)
1382			return -EBUSY;
1383		i3c_bus_set_addr_slot_status(&master->bus,
1384					     dev->info.dyn_addr,
1385					     I3C_ADDR_SLOT_I3C_DEV);
1386	}
1387
1388	if (master->ops->reattach_i3c_dev) {
1389		ret = master->ops->reattach_i3c_dev(dev, old_dyn_addr);
1390		if (ret) {
1391			i3c_master_put_i3c_addrs(dev);
1392			return ret;
1393		}
1394	}
1395
1396	return 0;
1397}
1398
1399static void i3c_master_detach_i3c_dev(struct i3c_dev_desc *dev)
1400{
1401	struct i3c_master_controller *master = i3c_dev_get_master(dev);
1402
1403	/* Do not detach the master device itself. */
1404	if (master->this != dev && master->ops->detach_i3c_dev)
1405		master->ops->detach_i3c_dev(dev);
1406
1407	i3c_master_put_i3c_addrs(dev);
1408	list_del(&dev->common.node);
1409}
1410
1411static int i3c_master_attach_i2c_dev(struct i3c_master_controller *master,
1412				     struct i2c_dev_desc *dev)
1413{
1414	int ret;
1415
1416	if (master->ops->attach_i2c_dev) {
1417		ret = master->ops->attach_i2c_dev(dev);
1418		if (ret)
1419			return ret;
1420	}
1421
1422	list_add_tail(&dev->common.node, &master->bus.devs.i2c);
1423
1424	return 0;
1425}
1426
1427static void i3c_master_detach_i2c_dev(struct i2c_dev_desc *dev)
1428{
1429	struct i3c_master_controller *master = i2c_dev_get_master(dev);
1430
1431	list_del(&dev->common.node);
1432
1433	if (master->ops->detach_i2c_dev)
1434		master->ops->detach_i2c_dev(dev);
1435}
1436
1437static int i3c_master_early_i3c_dev_add(struct i3c_master_controller *master,
1438					  struct i3c_dev_boardinfo *boardinfo)
1439{
1440	struct i3c_device_info info = {
1441		.static_addr = boardinfo->static_addr,
1442	};
1443	struct i3c_dev_desc *i3cdev;
1444	int ret;
1445
1446	i3cdev = i3c_master_alloc_i3c_dev(master, &info);
1447	if (IS_ERR(i3cdev))
1448		return -ENOMEM;
1449
1450	i3cdev->boardinfo = boardinfo;
1451
1452	ret = i3c_master_attach_i3c_dev(master, i3cdev);
1453	if (ret)
1454		goto err_free_dev;
1455
1456	ret = i3c_master_setdasa_locked(master, i3cdev->info.static_addr,
1457					i3cdev->boardinfo->init_dyn_addr);
1458	if (ret)
1459		goto err_detach_dev;
1460
1461	i3cdev->info.dyn_addr = i3cdev->boardinfo->init_dyn_addr;
1462	ret = i3c_master_reattach_i3c_dev(i3cdev, 0);
1463	if (ret)
1464		goto err_rstdaa;
1465
1466	ret = i3c_master_retrieve_dev_info(i3cdev);
1467	if (ret)
1468		goto err_rstdaa;
1469
1470	return 0;
1471
1472err_rstdaa:
1473	i3c_master_rstdaa_locked(master, i3cdev->boardinfo->init_dyn_addr);
1474err_detach_dev:
1475	i3c_master_detach_i3c_dev(i3cdev);
1476err_free_dev:
1477	i3c_master_free_i3c_dev(i3cdev);
1478
1479	return ret;
1480}
1481
1482static void
1483i3c_master_register_new_i3c_devs(struct i3c_master_controller *master)
1484{
1485	struct i3c_dev_desc *desc;
1486	int ret;
1487
1488	if (!master->init_done)
1489		return;
1490
1491	i3c_bus_for_each_i3cdev(&master->bus, desc) {
1492		if (desc->dev || !desc->info.dyn_addr || desc == master->this)
1493			continue;
1494
1495		desc->dev = kzalloc(sizeof(*desc->dev), GFP_KERNEL);
1496		if (!desc->dev)
1497			continue;
1498
1499		desc->dev->bus = &master->bus;
1500		desc->dev->desc = desc;
1501		desc->dev->dev.parent = &master->dev;
1502		desc->dev->dev.type = &i3c_device_type;
1503		desc->dev->dev.bus = &i3c_bus_type;
1504		desc->dev->dev.release = i3c_device_release;
1505		dev_set_name(&desc->dev->dev, "%d-%llx", master->bus.id,
1506			     desc->info.pid);
1507
1508		if (desc->boardinfo)
1509			desc->dev->dev.of_node = desc->boardinfo->of_node;
1510
1511		ret = device_register(&desc->dev->dev);
1512		if (ret) {
1513			dev_err(&master->dev,
1514				"Failed to add I3C device (err = %d)\n", ret);
1515			put_device(&desc->dev->dev);
1516		}
1517	}
1518}
1519
1520/**
1521 * i3c_master_do_daa() - do a DAA (Dynamic Address Assignment)
1522 * @master: master doing the DAA
1523 *
1524 * This function is instantiating an I3C device object and adding it to the
1525 * I3C device list. All device information are automatically retrieved using
1526 * standard CCC commands.
1527 *
1528 * The I3C device object is returned in case the master wants to attach
1529 * private data to it using i3c_dev_set_master_data().
1530 *
1531 * This function must be called with the bus lock held in write mode.
1532 *
1533 * Return: a 0 in case of success, an negative error code otherwise.
1534 */
1535int i3c_master_do_daa(struct i3c_master_controller *master)
1536{
1537	int ret;
1538
1539	i3c_bus_maintenance_lock(&master->bus);
1540	ret = master->ops->do_daa(master);
1541	i3c_bus_maintenance_unlock(&master->bus);
1542
1543	if (ret)
1544		return ret;
1545
1546	i3c_bus_normaluse_lock(&master->bus);
1547	i3c_master_register_new_i3c_devs(master);
1548	i3c_bus_normaluse_unlock(&master->bus);
1549
1550	return 0;
1551}
1552EXPORT_SYMBOL_GPL(i3c_master_do_daa);
1553
1554/**
1555 * i3c_master_set_info() - set master device information
1556 * @master: master used to send frames on the bus
1557 * @info: I3C device information
1558 *
1559 * Set master device info. This should be called from
1560 * &i3c_master_controller_ops->bus_init().
1561 *
1562 * Not all &i3c_device_info fields are meaningful for a master device.
1563 * Here is a list of fields that should be properly filled:
1564 *
1565 * - &i3c_device_info->dyn_addr
1566 * - &i3c_device_info->bcr
1567 * - &i3c_device_info->dcr
1568 * - &i3c_device_info->pid
1569 * - &i3c_device_info->hdr_cap if %I3C_BCR_HDR_CAP bit is set in
1570 *   &i3c_device_info->bcr
1571 *
1572 * This function must be called with the bus lock held in maintenance mode.
1573 *
1574 * Return: 0 if @info contains valid information (not every piece of
1575 * information can be checked, but we can at least make sure @info->dyn_addr
1576 * and @info->bcr are correct), -EINVAL otherwise.
1577 */
1578int i3c_master_set_info(struct i3c_master_controller *master,
1579			const struct i3c_device_info *info)
1580{
1581	struct i3c_dev_desc *i3cdev;
1582	int ret;
1583
1584	if (!i3c_bus_dev_addr_is_avail(&master->bus, info->dyn_addr))
1585		return -EINVAL;
1586
1587	if (I3C_BCR_DEVICE_ROLE(info->bcr) == I3C_BCR_I3C_MASTER &&
1588	    master->secondary)
1589		return -EINVAL;
1590
1591	if (master->this)
1592		return -EINVAL;
1593
1594	i3cdev = i3c_master_alloc_i3c_dev(master, info);
1595	if (IS_ERR(i3cdev))
1596		return PTR_ERR(i3cdev);
1597
1598	master->this = i3cdev;
1599	master->bus.cur_master = master->this;
1600
1601	ret = i3c_master_attach_i3c_dev(master, i3cdev);
1602	if (ret)
1603		goto err_free_dev;
1604
1605	return 0;
1606
1607err_free_dev:
1608	i3c_master_free_i3c_dev(i3cdev);
1609
1610	return ret;
1611}
1612EXPORT_SYMBOL_GPL(i3c_master_set_info);
1613
1614static void i3c_master_detach_free_devs(struct i3c_master_controller *master)
1615{
1616	struct i3c_dev_desc *i3cdev, *i3ctmp;
1617	struct i2c_dev_desc *i2cdev, *i2ctmp;
1618
1619	list_for_each_entry_safe(i3cdev, i3ctmp, &master->bus.devs.i3c,
1620				 common.node) {
1621		i3c_master_detach_i3c_dev(i3cdev);
1622
1623		if (i3cdev->boardinfo && i3cdev->boardinfo->init_dyn_addr)
1624			i3c_bus_set_addr_slot_status(&master->bus,
1625					i3cdev->boardinfo->init_dyn_addr,
1626					I3C_ADDR_SLOT_FREE);
1627
1628		i3c_master_free_i3c_dev(i3cdev);
1629	}
1630
1631	list_for_each_entry_safe(i2cdev, i2ctmp, &master->bus.devs.i2c,
1632				 common.node) {
1633		i3c_master_detach_i2c_dev(i2cdev);
1634		i3c_bus_set_addr_slot_status(&master->bus,
1635					     i2cdev->addr,
1636					     I3C_ADDR_SLOT_FREE);
1637		i3c_master_free_i2c_dev(i2cdev);
1638	}
1639}
1640
1641/**
1642 * i3c_master_bus_init() - initialize an I3C bus
1643 * @master: main master initializing the bus
1644 *
1645 * This function is following all initialisation steps described in the I3C
1646 * specification:
1647 *
1648 * 1. Attach I2C devs to the master so that the master can fill its internal
1649 *    device table appropriately
1650 *
1651 * 2. Call &i3c_master_controller_ops->bus_init() method to initialize
1652 *    the master controller. That's usually where the bus mode is selected
1653 *    (pure bus or mixed fast/slow bus)
1654 *
1655 * 3. Instruct all devices on the bus to drop their dynamic address. This is
1656 *    particularly important when the bus was previously configured by someone
1657 *    else (for example the bootloader)
1658 *
1659 * 4. Disable all slave events.
1660 *
1661 * 5. Reserve address slots for I3C devices with init_dyn_addr. And if devices
1662 *    also have static_addr, try to pre-assign dynamic addresses requested by
1663 *    the FW with SETDASA and attach corresponding statically defined I3C
1664 *    devices to the master.
1665 *
1666 * 6. Do a DAA (Dynamic Address Assignment) to assign dynamic addresses to all
1667 *    remaining I3C devices
1668 *
1669 * Once this is done, all I3C and I2C devices should be usable.
1670 *
1671 * Return: a 0 in case of success, an negative error code otherwise.
1672 */
1673static int i3c_master_bus_init(struct i3c_master_controller *master)
1674{
1675	enum i3c_addr_slot_status status;
1676	struct i2c_dev_boardinfo *i2cboardinfo;
1677	struct i3c_dev_boardinfo *i3cboardinfo;
1678	struct i2c_dev_desc *i2cdev;
1679	int ret;
1680
1681	/*
1682	 * First attach all devices with static definitions provided by the
1683	 * FW.
1684	 */
1685	list_for_each_entry(i2cboardinfo, &master->boardinfo.i2c, node) {
1686		status = i3c_bus_get_addr_slot_status(&master->bus,
1687						      i2cboardinfo->base.addr);
1688		if (status != I3C_ADDR_SLOT_FREE) {
1689			ret = -EBUSY;
1690			goto err_detach_devs;
1691		}
1692
1693		i3c_bus_set_addr_slot_status(&master->bus,
1694					     i2cboardinfo->base.addr,
1695					     I3C_ADDR_SLOT_I2C_DEV);
1696
1697		i2cdev = i3c_master_alloc_i2c_dev(master, i2cboardinfo);
1698		if (IS_ERR(i2cdev)) {
1699			ret = PTR_ERR(i2cdev);
1700			goto err_detach_devs;
1701		}
1702
1703		ret = i3c_master_attach_i2c_dev(master, i2cdev);
1704		if (ret) {
1705			i3c_master_free_i2c_dev(i2cdev);
1706			goto err_detach_devs;
1707		}
1708	}
1709
1710	/*
1711	 * Now execute the controller specific ->bus_init() routine, which
1712	 * might configure its internal logic to match the bus limitations.
1713	 */
1714	ret = master->ops->bus_init(master);
1715	if (ret)
1716		goto err_detach_devs;
1717
1718	/*
1719	 * The master device should have been instantiated in ->bus_init(),
1720	 * complain if this was not the case.
1721	 */
1722	if (!master->this) {
1723		dev_err(&master->dev,
1724			"master_set_info() was not called in ->bus_init()\n");
1725		ret = -EINVAL;
1726		goto err_bus_cleanup;
1727	}
1728
1729	/*
1730	 * Reset all dynamic address that may have been assigned before
1731	 * (assigned by the bootloader for example).
1732	 */
1733	ret = i3c_master_rstdaa_locked(master, I3C_BROADCAST_ADDR);
1734	if (ret && ret != I3C_ERROR_M2)
1735		goto err_bus_cleanup;
1736
1737	/* Disable all slave events before starting DAA. */
1738	ret = i3c_master_disec_locked(master, I3C_BROADCAST_ADDR,
1739				      I3C_CCC_EVENT_SIR | I3C_CCC_EVENT_MR |
1740				      I3C_CCC_EVENT_HJ);
1741	if (ret && ret != I3C_ERROR_M2)
1742		goto err_bus_cleanup;
1743
1744	/*
1745	 * Reserve init_dyn_addr first, and then try to pre-assign dynamic
1746	 * address and retrieve device information if needed.
1747	 * In case pre-assign dynamic address fails, setting dynamic address to
1748	 * the requested init_dyn_addr is retried after DAA is done in
1749	 * i3c_master_add_i3c_dev_locked().
1750	 */
1751	list_for_each_entry(i3cboardinfo, &master->boardinfo.i3c, node) {
1752
1753		/*
1754		 * We don't reserve a dynamic address for devices that
1755		 * don't explicitly request one.
1756		 */
1757		if (!i3cboardinfo->init_dyn_addr)
1758			continue;
1759
1760		ret = i3c_bus_get_addr_slot_status(&master->bus,
1761						   i3cboardinfo->init_dyn_addr);
1762		if (ret != I3C_ADDR_SLOT_FREE) {
1763			ret = -EBUSY;
1764			goto err_rstdaa;
1765		}
1766
1767		i3c_bus_set_addr_slot_status(&master->bus,
1768					     i3cboardinfo->init_dyn_addr,
1769					     I3C_ADDR_SLOT_I3C_DEV);
1770
1771		/*
1772		 * Only try to create/attach devices that have a static
1773		 * address. Other devices will be created/attached when
1774		 * DAA happens, and the requested dynamic address will
1775		 * be set using SETNEWDA once those devices become
1776		 * addressable.
1777		 */
1778
1779		if (i3cboardinfo->static_addr)
1780			i3c_master_early_i3c_dev_add(master, i3cboardinfo);
1781	}
1782
1783	ret = i3c_master_do_daa(master);
1784	if (ret)
1785		goto err_rstdaa;
1786
1787	return 0;
1788
1789err_rstdaa:
1790	i3c_master_rstdaa_locked(master, I3C_BROADCAST_ADDR);
1791
1792err_bus_cleanup:
1793	if (master->ops->bus_cleanup)
1794		master->ops->bus_cleanup(master);
1795
1796err_detach_devs:
1797	i3c_master_detach_free_devs(master);
1798
1799	return ret;
1800}
1801
1802static void i3c_master_bus_cleanup(struct i3c_master_controller *master)
1803{
1804	if (master->ops->bus_cleanup)
1805		master->ops->bus_cleanup(master);
1806
1807	i3c_master_detach_free_devs(master);
1808}
1809
1810static void i3c_master_attach_boardinfo(struct i3c_dev_desc *i3cdev)
1811{
1812	struct i3c_master_controller *master = i3cdev->common.master;
1813	struct i3c_dev_boardinfo *i3cboardinfo;
1814
1815	list_for_each_entry(i3cboardinfo, &master->boardinfo.i3c, node) {
1816		if (i3cdev->info.pid != i3cboardinfo->pid)
1817			continue;
1818
1819		i3cdev->boardinfo = i3cboardinfo;
1820		i3cdev->info.static_addr = i3cboardinfo->static_addr;
1821		return;
1822	}
1823}
1824
1825static struct i3c_dev_desc *
1826i3c_master_search_i3c_dev_duplicate(struct i3c_dev_desc *refdev)
1827{
1828	struct i3c_master_controller *master = i3c_dev_get_master(refdev);
1829	struct i3c_dev_desc *i3cdev;
1830
1831	i3c_bus_for_each_i3cdev(&master->bus, i3cdev) {
1832		if (i3cdev != refdev && i3cdev->info.pid == refdev->info.pid)
1833			return i3cdev;
1834	}
1835
1836	return NULL;
1837}
1838
1839/**
1840 * i3c_master_add_i3c_dev_locked() - add an I3C slave to the bus
1841 * @master: master used to send frames on the bus
1842 * @addr: I3C slave dynamic address assigned to the device
1843 *
1844 * This function is instantiating an I3C device object and adding it to the
1845 * I3C device list. All device information are automatically retrieved using
1846 * standard CCC commands.
1847 *
1848 * The I3C device object is returned in case the master wants to attach
1849 * private data to it using i3c_dev_set_master_data().
1850 *
1851 * This function must be called with the bus lock held in write mode.
1852 *
1853 * Return: a 0 in case of success, an negative error code otherwise.
1854 */
1855int i3c_master_add_i3c_dev_locked(struct i3c_master_controller *master,
1856				  u8 addr)
1857{
1858	struct i3c_device_info info = { .dyn_addr = addr };
1859	struct i3c_dev_desc *newdev, *olddev;
1860	u8 old_dyn_addr = addr, expected_dyn_addr;
1861	struct i3c_ibi_setup ibireq = { };
1862	bool enable_ibi = false;
1863	int ret;
1864
1865	if (!master)
1866		return -EINVAL;
1867
1868	newdev = i3c_master_alloc_i3c_dev(master, &info);
1869	if (IS_ERR(newdev))
1870		return PTR_ERR(newdev);
1871
1872	ret = i3c_master_attach_i3c_dev(master, newdev);
1873	if (ret)
1874		goto err_free_dev;
1875
1876	ret = i3c_master_retrieve_dev_info(newdev);
1877	if (ret)
1878		goto err_detach_dev;
1879
1880	i3c_master_attach_boardinfo(newdev);
1881
1882	olddev = i3c_master_search_i3c_dev_duplicate(newdev);
1883	if (olddev) {
1884		newdev->dev = olddev->dev;
1885		if (newdev->dev)
1886			newdev->dev->desc = newdev;
1887
1888		/*
1889		 * We need to restore the IBI state too, so let's save the
1890		 * IBI information and try to restore them after olddev has
1891		 * been detached+released and its IBI has been stopped and
1892		 * the associated resources have been freed.
1893		 */
1894		mutex_lock(&olddev->ibi_lock);
1895		if (olddev->ibi) {
1896			ibireq.handler = olddev->ibi->handler;
1897			ibireq.max_payload_len = olddev->ibi->max_payload_len;
1898			ibireq.num_slots = olddev->ibi->num_slots;
1899
1900			if (olddev->ibi->enabled) {
1901				enable_ibi = true;
1902				i3c_dev_disable_ibi_locked(olddev);
1903			}
1904
1905			i3c_dev_free_ibi_locked(olddev);
1906		}
1907		mutex_unlock(&olddev->ibi_lock);
1908
1909		old_dyn_addr = olddev->info.dyn_addr;
1910
1911		i3c_master_detach_i3c_dev(olddev);
1912		i3c_master_free_i3c_dev(olddev);
1913	}
1914
1915	ret = i3c_master_reattach_i3c_dev(newdev, old_dyn_addr);
1916	if (ret)
1917		goto err_detach_dev;
1918
1919	/*
1920	 * Depending on our previous state, the expected dynamic address might
1921	 * differ:
1922	 * - if the device already had a dynamic address assigned, let's try to
1923	 *   re-apply this one
1924	 * - if the device did not have a dynamic address and the firmware
1925	 *   requested a specific address, pick this one
1926	 * - in any other case, keep the address automatically assigned by the
1927	 *   master
1928	 */
1929	if (old_dyn_addr && old_dyn_addr != newdev->info.dyn_addr)
1930		expected_dyn_addr = old_dyn_addr;
1931	else if (newdev->boardinfo && newdev->boardinfo->init_dyn_addr)
1932		expected_dyn_addr = newdev->boardinfo->init_dyn_addr;
1933	else
1934		expected_dyn_addr = newdev->info.dyn_addr;
1935
1936	if (newdev->info.dyn_addr != expected_dyn_addr) {
1937		/*
1938		 * Try to apply the expected dynamic address. If it fails, keep
1939		 * the address assigned by the master.
1940		 */
1941		ret = i3c_master_setnewda_locked(master,
1942						 newdev->info.dyn_addr,
1943						 expected_dyn_addr);
1944		if (!ret) {
1945			old_dyn_addr = newdev->info.dyn_addr;
1946			newdev->info.dyn_addr = expected_dyn_addr;
1947			i3c_master_reattach_i3c_dev(newdev, old_dyn_addr);
1948		} else {
1949			dev_err(&master->dev,
1950				"Failed to assign reserved/old address to device %d%llx",
1951				master->bus.id, newdev->info.pid);
1952		}
1953	}
1954
1955	/*
1956	 * Now is time to try to restore the IBI setup. If we're lucky,
1957	 * everything works as before, otherwise, all we can do is complain.
1958	 * FIXME: maybe we should add callback to inform the driver that it
1959	 * should request the IBI again instead of trying to hide that from
1960	 * him.
1961	 */
1962	if (ibireq.handler) {
1963		mutex_lock(&newdev->ibi_lock);
1964		ret = i3c_dev_request_ibi_locked(newdev, &ibireq);
1965		if (ret) {
1966			dev_err(&master->dev,
1967				"Failed to request IBI on device %d-%llx",
1968				master->bus.id, newdev->info.pid);
1969		} else if (enable_ibi) {
1970			ret = i3c_dev_enable_ibi_locked(newdev);
1971			if (ret)
1972				dev_err(&master->dev,
1973					"Failed to re-enable IBI on device %d-%llx",
1974					master->bus.id, newdev->info.pid);
1975		}
1976		mutex_unlock(&newdev->ibi_lock);
1977	}
1978
1979	return 0;
1980
1981err_detach_dev:
1982	if (newdev->dev && newdev->dev->desc)
1983		newdev->dev->desc = NULL;
1984
1985	i3c_master_detach_i3c_dev(newdev);
1986
1987err_free_dev:
1988	i3c_master_free_i3c_dev(newdev);
1989
1990	return ret;
1991}
1992EXPORT_SYMBOL_GPL(i3c_master_add_i3c_dev_locked);
1993
1994#define OF_I3C_REG1_IS_I2C_DEV			BIT(31)
1995
1996static int
1997of_i3c_master_add_i2c_boardinfo(struct i3c_master_controller *master,
1998				struct device_node *node, u32 *reg)
1999{
2000	struct i2c_dev_boardinfo *boardinfo;
2001	struct device *dev = &master->dev;
2002	int ret;
2003
2004	boardinfo = devm_kzalloc(dev, sizeof(*boardinfo), GFP_KERNEL);
2005	if (!boardinfo)
2006		return -ENOMEM;
2007
2008	ret = of_i2c_get_board_info(dev, node, &boardinfo->base);
2009	if (ret)
2010		return ret;
2011
2012	/*
2013	 * The I3C Specification does not clearly say I2C devices with 10-bit
2014	 * address are supported. These devices can't be passed properly through
2015	 * DEFSLVS command.
2016	 */
2017	if (boardinfo->base.flags & I2C_CLIENT_TEN) {
2018		dev_err(dev, "I2C device with 10 bit address not supported.");
2019		return -ENOTSUPP;
2020	}
2021
2022	/* LVR is encoded in reg[2]. */
2023	boardinfo->lvr = reg[2];
2024
2025	list_add_tail(&boardinfo->node, &master->boardinfo.i2c);
2026	of_node_get(node);
2027
2028	return 0;
2029}
2030
2031static int
2032of_i3c_master_add_i3c_boardinfo(struct i3c_master_controller *master,
2033				struct device_node *node, u32 *reg)
2034{
2035	struct i3c_dev_boardinfo *boardinfo;
2036	struct device *dev = &master->dev;
2037	enum i3c_addr_slot_status addrstatus;
2038	u32 init_dyn_addr = 0;
2039
2040	boardinfo = devm_kzalloc(dev, sizeof(*boardinfo), GFP_KERNEL);
2041	if (!boardinfo)
2042		return -ENOMEM;
2043
2044	if (reg[0]) {
2045		if (reg[0] > I3C_MAX_ADDR)
2046			return -EINVAL;
2047
2048		addrstatus = i3c_bus_get_addr_slot_status(&master->bus,
2049							  reg[0]);
2050		if (addrstatus != I3C_ADDR_SLOT_FREE)
2051			return -EINVAL;
2052	}
2053
2054	boardinfo->static_addr = reg[0];
2055
2056	if (!of_property_read_u32(node, "assigned-address", &init_dyn_addr)) {
2057		if (init_dyn_addr > I3C_MAX_ADDR)
2058			return -EINVAL;
2059
2060		addrstatus = i3c_bus_get_addr_slot_status(&master->bus,
2061							  init_dyn_addr);
2062		if (addrstatus != I3C_ADDR_SLOT_FREE)
2063			return -EINVAL;
2064	}
2065
2066	boardinfo->pid = ((u64)reg[1] << 32) | reg[2];
2067
2068	if ((boardinfo->pid & GENMASK_ULL(63, 48)) ||
2069	    I3C_PID_RND_LOWER_32BITS(boardinfo->pid))
2070		return -EINVAL;
2071
2072	boardinfo->init_dyn_addr = init_dyn_addr;
2073	boardinfo->of_node = of_node_get(node);
2074	list_add_tail(&boardinfo->node, &master->boardinfo.i3c);
2075
2076	return 0;
2077}
2078
2079static int of_i3c_master_add_dev(struct i3c_master_controller *master,
2080				 struct device_node *node)
2081{
2082	u32 reg[3];
2083	int ret;
2084
2085	if (!master || !node)
2086		return -EINVAL;
2087
2088	ret = of_property_read_u32_array(node, "reg", reg, ARRAY_SIZE(reg));
2089	if (ret)
2090		return ret;
2091
2092	/*
2093	 * The manufacturer ID can't be 0. If reg[1] == 0 that means we're
2094	 * dealing with an I2C device.
2095	 */
2096	if (!reg[1])
2097		ret = of_i3c_master_add_i2c_boardinfo(master, node, reg);
2098	else
2099		ret = of_i3c_master_add_i3c_boardinfo(master, node, reg);
2100
2101	return ret;
2102}
2103
2104static int of_populate_i3c_bus(struct i3c_master_controller *master)
2105{
2106	struct device *dev = &master->dev;
2107	struct device_node *i3cbus_np = dev->of_node;
2108	struct device_node *node;
2109	int ret;
2110	u32 val;
2111
2112	if (!i3cbus_np)
2113		return 0;
2114
2115	for_each_available_child_of_node(i3cbus_np, node) {
2116		ret = of_i3c_master_add_dev(master, node);
2117		if (ret) {
2118			of_node_put(node);
2119			return ret;
2120		}
2121	}
2122
2123	/*
2124	 * The user might want to limit I2C and I3C speed in case some devices
2125	 * on the bus are not supporting typical rates, or if the bus topology
2126	 * prevents it from using max possible rate.
2127	 */
2128	if (!of_property_read_u32(i3cbus_np, "i2c-scl-hz", &val))
2129		master->bus.scl_rate.i2c = val;
2130
2131	if (!of_property_read_u32(i3cbus_np, "i3c-scl-hz", &val))
2132		master->bus.scl_rate.i3c = val;
2133
2134	return 0;
2135}
2136
2137static int i3c_master_i2c_adapter_xfer(struct i2c_adapter *adap,
2138				       struct i2c_msg *xfers, int nxfers)
2139{
2140	struct i3c_master_controller *master = i2c_adapter_to_i3c_master(adap);
2141	struct i2c_dev_desc *dev;
2142	int i, ret;
2143	u16 addr;
2144
2145	if (!xfers || !master || nxfers <= 0)
2146		return -EINVAL;
2147
2148	if (!master->ops->i2c_xfers)
2149		return -ENOTSUPP;
2150
2151	/* Doing transfers to different devices is not supported. */
2152	addr = xfers[0].addr;
2153	for (i = 1; i < nxfers; i++) {
2154		if (addr != xfers[i].addr)
2155			return -ENOTSUPP;
2156	}
2157
2158	i3c_bus_normaluse_lock(&master->bus);
2159	dev = i3c_master_find_i2c_dev_by_addr(master, addr);
2160	if (!dev)
2161		ret = -ENOENT;
2162	else
2163		ret = master->ops->i2c_xfers(dev, xfers, nxfers);
2164	i3c_bus_normaluse_unlock(&master->bus);
2165
2166	return ret ? ret : nxfers;
2167}
2168
2169static u32 i3c_master_i2c_funcs(struct i2c_adapter *adapter)
2170{
2171	return I2C_FUNC_SMBUS_EMUL | I2C_FUNC_I2C;
2172}
2173
2174static const struct i2c_algorithm i3c_master_i2c_algo = {
2175	.master_xfer = i3c_master_i2c_adapter_xfer,
2176	.functionality = i3c_master_i2c_funcs,
2177};
2178
2179static int i3c_master_i2c_adapter_init(struct i3c_master_controller *master)
2180{
2181	struct i2c_adapter *adap = i3c_master_to_i2c_adapter(master);
2182	struct i2c_dev_desc *i2cdev;
2183	int ret;
2184
2185	adap->dev.parent = master->dev.parent;
2186	adap->owner = master->dev.parent->driver->owner;
2187	adap->algo = &i3c_master_i2c_algo;
2188	strncpy(adap->name, dev_name(master->dev.parent), sizeof(adap->name));
2189
2190	/* FIXME: Should we allow i3c masters to override these values? */
2191	adap->timeout = 1000;
2192	adap->retries = 3;
2193
2194	ret = i2c_add_adapter(adap);
2195	if (ret)
2196		return ret;
2197
2198	/*
2199	 * We silently ignore failures here. The bus should keep working
2200	 * correctly even if one or more i2c devices are not registered.
2201	 */
2202	i3c_bus_for_each_i2cdev(&master->bus, i2cdev)
2203		i2cdev->dev = i2c_new_client_device(adap, &i2cdev->boardinfo->base);
2204
2205	return 0;
2206}
2207
2208static void i3c_master_i2c_adapter_cleanup(struct i3c_master_controller *master)
2209{
2210	struct i2c_dev_desc *i2cdev;
2211
2212	i2c_del_adapter(&master->i2c);
2213
2214	i3c_bus_for_each_i2cdev(&master->bus, i2cdev)
2215		i2cdev->dev = NULL;
2216}
2217
2218static void i3c_master_unregister_i3c_devs(struct i3c_master_controller *master)
2219{
2220	struct i3c_dev_desc *i3cdev;
2221
2222	i3c_bus_for_each_i3cdev(&master->bus, i3cdev) {
2223		if (!i3cdev->dev)
2224			continue;
2225
2226		i3cdev->dev->desc = NULL;
2227		if (device_is_registered(&i3cdev->dev->dev))
2228			device_unregister(&i3cdev->dev->dev);
2229		else
2230			put_device(&i3cdev->dev->dev);
2231		i3cdev->dev = NULL;
2232	}
2233}
2234
2235/**
2236 * i3c_master_queue_ibi() - Queue an IBI
2237 * @dev: the device this IBI is coming from
2238 * @slot: the IBI slot used to store the payload
2239 *
2240 * Queue an IBI to the controller workqueue. The IBI handler attached to
2241 * the dev will be called from a workqueue context.
2242 */
2243void i3c_master_queue_ibi(struct i3c_dev_desc *dev, struct i3c_ibi_slot *slot)
2244{
2245	atomic_inc(&dev->ibi->pending_ibis);
2246	queue_work(dev->common.master->wq, &slot->work);
2247}
2248EXPORT_SYMBOL_GPL(i3c_master_queue_ibi);
2249
2250static void i3c_master_handle_ibi(struct work_struct *work)
2251{
2252	struct i3c_ibi_slot *slot = container_of(work, struct i3c_ibi_slot,
2253						 work);
2254	struct i3c_dev_desc *dev = slot->dev;
2255	struct i3c_master_controller *master = i3c_dev_get_master(dev);
2256	struct i3c_ibi_payload payload;
2257
2258	payload.data = slot->data;
2259	payload.len = slot->len;
2260
2261	if (dev->dev)
2262		dev->ibi->handler(dev->dev, &payload);
2263
2264	master->ops->recycle_ibi_slot(dev, slot);
2265	if (atomic_dec_and_test(&dev->ibi->pending_ibis))
2266		complete(&dev->ibi->all_ibis_handled);
2267}
2268
2269static void i3c_master_init_ibi_slot(struct i3c_dev_desc *dev,
2270				     struct i3c_ibi_slot *slot)
2271{
2272	slot->dev = dev;
2273	INIT_WORK(&slot->work, i3c_master_handle_ibi);
2274}
2275
2276struct i3c_generic_ibi_slot {
2277	struct list_head node;
2278	struct i3c_ibi_slot base;
2279};
2280
2281struct i3c_generic_ibi_pool {
2282	spinlock_t lock;
2283	unsigned int num_slots;
2284	struct i3c_generic_ibi_slot *slots;
2285	void *payload_buf;
2286	struct list_head free_slots;
2287	struct list_head pending;
2288};
2289
2290/**
2291 * i3c_generic_ibi_free_pool() - Free a generic IBI pool
2292 * @pool: the IBI pool to free
2293 *
2294 * Free all IBI slots allated by a generic IBI pool.
2295 */
2296void i3c_generic_ibi_free_pool(struct i3c_generic_ibi_pool *pool)
2297{
2298	struct i3c_generic_ibi_slot *slot;
2299	unsigned int nslots = 0;
2300
2301	while (!list_empty(&pool->free_slots)) {
2302		slot = list_first_entry(&pool->free_slots,
2303					struct i3c_generic_ibi_slot, node);
2304		list_del(&slot->node);
2305		nslots++;
2306	}
2307
2308	/*
2309	 * If the number of freed slots is not equal to the number of allocated
2310	 * slots we have a leak somewhere.
2311	 */
2312	WARN_ON(nslots != pool->num_slots);
2313
2314	kfree(pool->payload_buf);
2315	kfree(pool->slots);
2316	kfree(pool);
2317}
2318EXPORT_SYMBOL_GPL(i3c_generic_ibi_free_pool);
2319
2320/**
2321 * i3c_generic_ibi_alloc_pool() - Create a generic IBI pool
2322 * @dev: the device this pool will be used for
2323 * @req: IBI setup request describing what the device driver expects
2324 *
2325 * Create a generic IBI pool based on the information provided in @req.
2326 *
2327 * Return: a valid IBI pool in case of success, an ERR_PTR() otherwise.
2328 */
2329struct i3c_generic_ibi_pool *
2330i3c_generic_ibi_alloc_pool(struct i3c_dev_desc *dev,
2331			   const struct i3c_ibi_setup *req)
2332{
2333	struct i3c_generic_ibi_pool *pool;
2334	struct i3c_generic_ibi_slot *slot;
2335	unsigned int i;
2336	int ret;
2337
2338	pool = kzalloc(sizeof(*pool), GFP_KERNEL);
2339	if (!pool)
2340		return ERR_PTR(-ENOMEM);
2341
2342	spin_lock_init(&pool->lock);
2343	INIT_LIST_HEAD(&pool->free_slots);
2344	INIT_LIST_HEAD(&pool->pending);
2345
2346	pool->slots = kcalloc(req->num_slots, sizeof(*slot), GFP_KERNEL);
2347	if (!pool->slots) {
2348		ret = -ENOMEM;
2349		goto err_free_pool;
2350	}
2351
2352	if (req->max_payload_len) {
2353		pool->payload_buf = kcalloc(req->num_slots,
2354					    req->max_payload_len, GFP_KERNEL);
2355		if (!pool->payload_buf) {
2356			ret = -ENOMEM;
2357			goto err_free_pool;
2358		}
2359	}
2360
2361	for (i = 0; i < req->num_slots; i++) {
2362		slot = &pool->slots[i];
2363		i3c_master_init_ibi_slot(dev, &slot->base);
2364
2365		if (req->max_payload_len)
2366			slot->base.data = pool->payload_buf +
2367					  (i * req->max_payload_len);
2368
2369		list_add_tail(&slot->node, &pool->free_slots);
2370		pool->num_slots++;
2371	}
2372
2373	return pool;
2374
2375err_free_pool:
2376	i3c_generic_ibi_free_pool(pool);
2377	return ERR_PTR(ret);
2378}
2379EXPORT_SYMBOL_GPL(i3c_generic_ibi_alloc_pool);
2380
2381/**
2382 * i3c_generic_ibi_get_free_slot() - Get a free slot from a generic IBI pool
2383 * @pool: the pool to query an IBI slot on
2384 *
2385 * Search for a free slot in a generic IBI pool.
2386 * The slot should be returned to the pool using i3c_generic_ibi_recycle_slot()
2387 * when it's no longer needed.
2388 *
2389 * Return: a pointer to a free slot, or NULL if there's no free slot available.
2390 */
2391struct i3c_ibi_slot *
2392i3c_generic_ibi_get_free_slot(struct i3c_generic_ibi_pool *pool)
2393{
2394	struct i3c_generic_ibi_slot *slot;
2395	unsigned long flags;
2396
2397	spin_lock_irqsave(&pool->lock, flags);
2398	slot = list_first_entry_or_null(&pool->free_slots,
2399					struct i3c_generic_ibi_slot, node);
2400	if (slot)
2401		list_del(&slot->node);
2402	spin_unlock_irqrestore(&pool->lock, flags);
2403
2404	return slot ? &slot->base : NULL;
2405}
2406EXPORT_SYMBOL_GPL(i3c_generic_ibi_get_free_slot);
2407
2408/**
2409 * i3c_generic_ibi_recycle_slot() - Return a slot to a generic IBI pool
2410 * @pool: the pool to return the IBI slot to
2411 * @s: IBI slot to recycle
2412 *
2413 * Add an IBI slot back to its generic IBI pool. Should be called from the
2414 * master driver struct_master_controller_ops->recycle_ibi() method.
2415 */
2416void i3c_generic_ibi_recycle_slot(struct i3c_generic_ibi_pool *pool,
2417				  struct i3c_ibi_slot *s)
2418{
2419	struct i3c_generic_ibi_slot *slot;
2420	unsigned long flags;
2421
2422	if (!s)
2423		return;
2424
2425	slot = container_of(s, struct i3c_generic_ibi_slot, base);
2426	spin_lock_irqsave(&pool->lock, flags);
2427	list_add_tail(&slot->node, &pool->free_slots);
2428	spin_unlock_irqrestore(&pool->lock, flags);
2429}
2430EXPORT_SYMBOL_GPL(i3c_generic_ibi_recycle_slot);
2431
2432static int i3c_master_check_ops(const struct i3c_master_controller_ops *ops)
2433{
2434	if (!ops || !ops->bus_init || !ops->priv_xfers ||
2435	    !ops->send_ccc_cmd || !ops->do_daa || !ops->i2c_xfers)
2436		return -EINVAL;
2437
2438	if (ops->request_ibi &&
2439	    (!ops->enable_ibi || !ops->disable_ibi || !ops->free_ibi ||
2440	     !ops->recycle_ibi_slot))
2441		return -EINVAL;
2442
2443	return 0;
2444}
2445
2446/**
2447 * i3c_master_register() - register an I3C master
2448 * @master: master used to send frames on the bus
2449 * @parent: the parent device (the one that provides this I3C master
2450 *	    controller)
2451 * @ops: the master controller operations
2452 * @secondary: true if you are registering a secondary master. Will return
2453 *	       -ENOTSUPP if set to true since secondary masters are not yet
2454 *	       supported
2455 *
2456 * This function takes care of everything for you:
2457 *
2458 * - creates and initializes the I3C bus
2459 * - populates the bus with static I2C devs if @parent->of_node is not
2460 *   NULL
2461 * - registers all I3C devices added by the controller during bus
2462 *   initialization
2463 * - registers the I2C adapter and all I2C devices
2464 *
2465 * Return: 0 in case of success, a negative error code otherwise.
2466 */
2467int i3c_master_register(struct i3c_master_controller *master,
2468			struct device *parent,
2469			const struct i3c_master_controller_ops *ops,
2470			bool secondary)
2471{
2472	unsigned long i2c_scl_rate = I3C_BUS_I2C_FM_PLUS_SCL_RATE;
2473	struct i3c_bus *i3cbus = i3c_master_get_bus(master);
2474	enum i3c_bus_mode mode = I3C_BUS_MODE_PURE;
2475	struct i2c_dev_boardinfo *i2cbi;
2476	int ret;
2477
2478	/* We do not support secondary masters yet. */
2479	if (secondary)
2480		return -ENOTSUPP;
2481
2482	ret = i3c_master_check_ops(ops);
2483	if (ret)
2484		return ret;
2485
2486	master->dev.parent = parent;
2487	master->dev.of_node = of_node_get(parent->of_node);
2488	master->dev.bus = &i3c_bus_type;
2489	master->dev.type = &i3c_masterdev_type;
2490	master->dev.release = i3c_masterdev_release;
2491	master->ops = ops;
2492	master->secondary = secondary;
2493	INIT_LIST_HEAD(&master->boardinfo.i2c);
2494	INIT_LIST_HEAD(&master->boardinfo.i3c);
2495
2496	ret = i3c_bus_init(i3cbus);
2497	if (ret)
2498		return ret;
2499
2500	device_initialize(&master->dev);
2501	dev_set_name(&master->dev, "i3c-%d", i3cbus->id);
2502
2503	ret = of_populate_i3c_bus(master);
2504	if (ret)
2505		goto err_put_dev;
2506
2507	list_for_each_entry(i2cbi, &master->boardinfo.i2c, node) {
2508		switch (i2cbi->lvr & I3C_LVR_I2C_INDEX_MASK) {
2509		case I3C_LVR_I2C_INDEX(0):
2510			if (mode < I3C_BUS_MODE_MIXED_FAST)
2511				mode = I3C_BUS_MODE_MIXED_FAST;
2512			break;
2513		case I3C_LVR_I2C_INDEX(1):
2514			if (mode < I3C_BUS_MODE_MIXED_LIMITED)
2515				mode = I3C_BUS_MODE_MIXED_LIMITED;
2516			break;
2517		case I3C_LVR_I2C_INDEX(2):
2518			if (mode < I3C_BUS_MODE_MIXED_SLOW)
2519				mode = I3C_BUS_MODE_MIXED_SLOW;
2520			break;
2521		default:
2522			ret = -EINVAL;
2523			goto err_put_dev;
2524		}
2525
2526		if (i2cbi->lvr & I3C_LVR_I2C_FM_MODE)
2527			i2c_scl_rate = I3C_BUS_I2C_FM_SCL_RATE;
2528	}
2529
2530	ret = i3c_bus_set_mode(i3cbus, mode, i2c_scl_rate);
2531	if (ret)
2532		goto err_put_dev;
2533
2534	master->wq = alloc_workqueue("%s", 0, 0, dev_name(parent));
2535	if (!master->wq) {
2536		ret = -ENOMEM;
2537		goto err_put_dev;
2538	}
2539
2540	ret = i3c_master_bus_init(master);
2541	if (ret)
2542		goto err_put_dev;
2543
2544	ret = device_add(&master->dev);
2545	if (ret)
2546		goto err_cleanup_bus;
2547
2548	/*
2549	 * Expose our I3C bus as an I2C adapter so that I2C devices are exposed
2550	 * through the I2C subsystem.
2551	 */
2552	ret = i3c_master_i2c_adapter_init(master);
2553	if (ret)
2554		goto err_del_dev;
2555
2556	/*
2557	 * We're done initializing the bus and the controller, we can now
2558	 * register I3C devices discovered during the initial DAA.
2559	 */
2560	master->init_done = true;
2561	i3c_bus_normaluse_lock(&master->bus);
2562	i3c_master_register_new_i3c_devs(master);
2563	i3c_bus_normaluse_unlock(&master->bus);
2564
2565	return 0;
2566
2567err_del_dev:
2568	device_del(&master->dev);
2569
2570err_cleanup_bus:
2571	i3c_master_bus_cleanup(master);
2572
2573err_put_dev:
2574	put_device(&master->dev);
2575
2576	return ret;
2577}
2578EXPORT_SYMBOL_GPL(i3c_master_register);
2579
2580/**
2581 * i3c_master_unregister() - unregister an I3C master
2582 * @master: master used to send frames on the bus
2583 *
2584 * Basically undo everything done in i3c_master_register().
2585 *
2586 * Return: 0 in case of success, a negative error code otherwise.
2587 */
2588int i3c_master_unregister(struct i3c_master_controller *master)
2589{
2590	i3c_master_i2c_adapter_cleanup(master);
2591	i3c_master_unregister_i3c_devs(master);
2592	i3c_master_bus_cleanup(master);
2593	device_unregister(&master->dev);
2594
2595	return 0;
2596}
2597EXPORT_SYMBOL_GPL(i3c_master_unregister);
2598
2599int i3c_dev_do_priv_xfers_locked(struct i3c_dev_desc *dev,
2600				 struct i3c_priv_xfer *xfers,
2601				 int nxfers)
2602{
2603	struct i3c_master_controller *master;
2604
2605	if (!dev)
2606		return -ENOENT;
2607
2608	master = i3c_dev_get_master(dev);
2609	if (!master || !xfers)
2610		return -EINVAL;
2611
2612	if (!master->ops->priv_xfers)
2613		return -ENOTSUPP;
2614
2615	return master->ops->priv_xfers(dev, xfers, nxfers);
2616}
2617
2618int i3c_dev_disable_ibi_locked(struct i3c_dev_desc *dev)
2619{
2620	struct i3c_master_controller *master;
2621	int ret;
2622
2623	if (!dev->ibi)
2624		return -EINVAL;
2625
2626	master = i3c_dev_get_master(dev);
2627	ret = master->ops->disable_ibi(dev);
2628	if (ret)
2629		return ret;
2630
2631	reinit_completion(&dev->ibi->all_ibis_handled);
2632	if (atomic_read(&dev->ibi->pending_ibis))
2633		wait_for_completion(&dev->ibi->all_ibis_handled);
2634
2635	dev->ibi->enabled = false;
2636
2637	return 0;
2638}
2639
2640int i3c_dev_enable_ibi_locked(struct i3c_dev_desc *dev)
2641{
2642	struct i3c_master_controller *master = i3c_dev_get_master(dev);
2643	int ret;
2644
2645	if (!dev->ibi)
2646		return -EINVAL;
2647
2648	ret = master->ops->enable_ibi(dev);
2649	if (!ret)
2650		dev->ibi->enabled = true;
2651
2652	return ret;
2653}
2654
2655int i3c_dev_request_ibi_locked(struct i3c_dev_desc *dev,
2656			       const struct i3c_ibi_setup *req)
2657{
2658	struct i3c_master_controller *master = i3c_dev_get_master(dev);
2659	struct i3c_device_ibi_info *ibi;
2660	int ret;
2661
2662	if (!master->ops->request_ibi)
2663		return -ENOTSUPP;
2664
2665	if (dev->ibi)
2666		return -EBUSY;
2667
2668	ibi = kzalloc(sizeof(*ibi), GFP_KERNEL);
2669	if (!ibi)
2670		return -ENOMEM;
2671
2672	atomic_set(&ibi->pending_ibis, 0);
2673	init_completion(&ibi->all_ibis_handled);
2674	ibi->handler = req->handler;
2675	ibi->max_payload_len = req->max_payload_len;
2676	ibi->num_slots = req->num_slots;
2677
2678	dev->ibi = ibi;
2679	ret = master->ops->request_ibi(dev, req);
2680	if (ret) {
2681		kfree(ibi);
2682		dev->ibi = NULL;
2683	}
2684
2685	return ret;
2686}
2687
2688void i3c_dev_free_ibi_locked(struct i3c_dev_desc *dev)
2689{
2690	struct i3c_master_controller *master = i3c_dev_get_master(dev);
2691
2692	if (!dev->ibi)
2693		return;
2694
2695	if (WARN_ON(dev->ibi->enabled))
2696		WARN_ON(i3c_dev_disable_ibi_locked(dev));
2697
2698	master->ops->free_ibi(dev);
2699	kfree(dev->ibi);
2700	dev->ibi = NULL;
2701}
2702
2703static int __init i3c_init(void)
2704{
2705	return bus_register(&i3c_bus_type);
2706}
2707subsys_initcall(i3c_init);
2708
2709static void __exit i3c_exit(void)
2710{
2711	idr_destroy(&i3c_bus_idr);
2712	bus_unregister(&i3c_bus_type);
2713}
2714module_exit(i3c_exit);
2715
2716MODULE_AUTHOR("Boris Brezillon <boris.brezillon@bootlin.com>");
2717MODULE_DESCRIPTION("I3C core");
2718MODULE_LICENSE("GPL v2");
2719