1// SPDX-License-Identifier: (GPL-2.0 OR BSD-3-Clause)
2// Copyright(c) 2015-17 Intel Corporation.
3
4#include <linux/acpi.h>
5#include <linux/of.h>
6#include <linux/soundwire/sdw.h>
7#include <linux/soundwire/sdw_type.h>
8#include "bus.h"
9#include "sysfs_local.h"
10
11static void sdw_slave_release(struct device *dev)
12{
13	struct sdw_slave *slave = dev_to_sdw_dev(dev);
14
15	kfree(slave);
16}
17
18struct device_type sdw_slave_type = {
19	.name =		"sdw_slave",
20	.release =	sdw_slave_release,
21	.uevent =	sdw_slave_uevent,
22};
23
24int sdw_slave_add(struct sdw_bus *bus,
25		  struct sdw_slave_id *id, struct fwnode_handle *fwnode)
26{
27	struct sdw_slave *slave;
28	int ret;
29	int i;
30
31	slave = kzalloc(sizeof(*slave), GFP_KERNEL);
32	if (!slave)
33		return -ENOMEM;
34
35	/* Initialize data structure */
36	memcpy(&slave->id, id, sizeof(*id));
37	slave->dev.parent = bus->dev;
38	slave->dev.fwnode = fwnode;
39
40	if (id->unique_id == SDW_IGNORED_UNIQUE_ID) {
41		/* name shall be sdw:link:mfg:part:class */
42		dev_set_name(&slave->dev, "sdw:%x:%x:%x:%x",
43			     bus->link_id, id->mfg_id, id->part_id,
44			     id->class_id);
45	} else {
46		/* name shall be sdw:link:mfg:part:class:unique */
47		dev_set_name(&slave->dev, "sdw:%x:%x:%x:%x:%x",
48			     bus->link_id, id->mfg_id, id->part_id,
49			     id->class_id, id->unique_id);
50	}
51
52	slave->dev.bus = &sdw_bus_type;
53	slave->dev.of_node = of_node_get(to_of_node(fwnode));
54	slave->dev.type = &sdw_slave_type;
55	slave->dev.groups = sdw_slave_status_attr_groups;
56	slave->bus = bus;
57	slave->status = SDW_SLAVE_UNATTACHED;
58	init_completion(&slave->enumeration_complete);
59	init_completion(&slave->initialization_complete);
60	slave->dev_num = 0;
61	init_completion(&slave->probe_complete);
62	slave->probed = false;
63	slave->first_interrupt_done = false;
64
65	for (i = 0; i < SDW_MAX_PORTS; i++)
66		init_completion(&slave->port_ready[i]);
67
68	mutex_lock(&bus->bus_lock);
69	list_add_tail(&slave->node, &bus->slaves);
70	mutex_unlock(&bus->bus_lock);
71
72	ret = device_register(&slave->dev);
73	if (ret) {
74		dev_err(bus->dev, "Failed to add slave: ret %d\n", ret);
75
76		/*
77		 * On err, don't free but drop ref as this will be freed
78		 * when release method is invoked.
79		 */
80		mutex_lock(&bus->bus_lock);
81		list_del(&slave->node);
82		mutex_unlock(&bus->bus_lock);
83		put_device(&slave->dev);
84
85		return ret;
86	}
87	sdw_slave_debugfs_init(slave);
88
89	return ret;
90}
91
92#if IS_ENABLED(CONFIG_ACPI)
93
94static bool find_slave(struct sdw_bus *bus,
95		       struct acpi_device *adev,
96		       struct sdw_slave_id *id)
97{
98	unsigned long long addr;
99	unsigned int link_id;
100	acpi_status status;
101
102	status = acpi_evaluate_integer(adev->handle,
103				       METHOD_NAME__ADR, NULL, &addr);
104
105	if (ACPI_FAILURE(status)) {
106		dev_err(bus->dev, "_ADR resolution failed: %x\n",
107			status);
108		return false;
109	}
110
111	/* Extract link id from ADR, Bit 51 to 48 (included) */
112	link_id = SDW_DISCO_LINK_ID(addr);
113
114	/* Check for link_id match */
115	if (link_id != bus->link_id)
116		return false;
117
118	sdw_extract_slave_id(bus, addr, id);
119
120	return true;
121}
122
123/*
124 * sdw_acpi_find_slaves() - Find Slave devices in Master ACPI node
125 * @bus: SDW bus instance
126 *
127 * Scans Master ACPI node for SDW child Slave devices and registers it.
128 */
129int sdw_acpi_find_slaves(struct sdw_bus *bus)
130{
131	struct acpi_device *adev, *parent;
132	struct acpi_device *adev2, *parent2;
133
134	parent = ACPI_COMPANION(bus->dev);
135	if (!parent) {
136		dev_err(bus->dev, "Can't find parent for acpi bind\n");
137		return -ENODEV;
138	}
139
140	list_for_each_entry(adev, &parent->children, node) {
141		struct sdw_slave_id id;
142		struct sdw_slave_id id2;
143		bool ignore_unique_id = true;
144
145		if (!find_slave(bus, adev, &id))
146			continue;
147
148		/* brute-force O(N^2) search for duplicates */
149		parent2 = parent;
150		list_for_each_entry(adev2, &parent2->children, node) {
151
152			if (adev == adev2)
153				continue;
154
155			if (!find_slave(bus, adev2, &id2))
156				continue;
157
158			if (id.sdw_version != id2.sdw_version ||
159			    id.mfg_id != id2.mfg_id ||
160			    id.part_id != id2.part_id ||
161			    id.class_id != id2.class_id)
162				continue;
163
164			if (id.unique_id != id2.unique_id) {
165				dev_dbg(bus->dev,
166					"Valid unique IDs %x %x for Slave mfg %x part %d\n",
167					id.unique_id, id2.unique_id,
168					id.mfg_id, id.part_id);
169				ignore_unique_id = false;
170			} else {
171				dev_err(bus->dev,
172					"Invalid unique IDs %x %x for Slave mfg %x part %d\n",
173					id.unique_id, id2.unique_id,
174					id.mfg_id, id.part_id);
175				return -ENODEV;
176			}
177		}
178
179		if (ignore_unique_id)
180			id.unique_id = SDW_IGNORED_UNIQUE_ID;
181
182		/*
183		 * don't error check for sdw_slave_add as we want to continue
184		 * adding Slaves
185		 */
186		sdw_slave_add(bus, &id, acpi_fwnode_handle(adev));
187	}
188
189	return 0;
190}
191
192#endif
193
194/*
195 * sdw_of_find_slaves() - Find Slave devices in master device tree node
196 * @bus: SDW bus instance
197 *
198 * Scans Master DT node for SDW child Slave devices and registers it.
199 */
200int sdw_of_find_slaves(struct sdw_bus *bus)
201{
202	struct device *dev = bus->dev;
203	struct device_node *node;
204
205	for_each_child_of_node(bus->dev->of_node, node) {
206		int link_id, ret, len;
207		unsigned int sdw_version;
208		const char *compat = NULL;
209		struct sdw_slave_id id;
210		const __be32 *addr;
211
212		compat = of_get_property(node, "compatible", NULL);
213		if (!compat)
214			continue;
215
216		ret = sscanf(compat, "sdw%01x%04hx%04hx%02hhx", &sdw_version,
217			     &id.mfg_id, &id.part_id, &id.class_id);
218
219		if (ret != 4) {
220			dev_err(dev, "Invalid compatible string found %s\n",
221				compat);
222			continue;
223		}
224
225		addr = of_get_property(node, "reg", &len);
226		if (!addr || (len < 2 * sizeof(u32))) {
227			dev_err(dev, "Invalid Link and Instance ID\n");
228			continue;
229		}
230
231		link_id = be32_to_cpup(addr++);
232		id.unique_id = be32_to_cpup(addr);
233		id.sdw_version = sdw_version;
234
235		/* Check for link_id match */
236		if (link_id != bus->link_id)
237			continue;
238
239		sdw_slave_add(bus, &id, of_fwnode_handle(node));
240	}
241
242	return 0;
243}
244