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 mutex_destroy(lock: &slave->sdw_dev_lock);
16 kfree(objp: slave);
17}
18
19struct device_type sdw_slave_type = {
20 .name = "sdw_slave",
21 .release = sdw_slave_release,
22 .uevent = sdw_slave_uevent,
23};
24
25int sdw_slave_add(struct sdw_bus *bus,
26 struct sdw_slave_id *id, struct fwnode_handle *fwnode)
27{
28 struct sdw_slave *slave;
29 int ret;
30 int i;
31
32 slave = kzalloc(size: sizeof(*slave), GFP_KERNEL);
33 if (!slave)
34 return -ENOMEM;
35
36 /* Initialize data structure */
37 memcpy(&slave->id, id, sizeof(*id));
38 slave->dev.parent = bus->dev;
39 slave->dev.fwnode = fwnode;
40
41 if (id->unique_id == SDW_IGNORED_UNIQUE_ID) {
42 /* name shall be sdw:link:mfg:part:class */
43 dev_set_name(dev: &slave->dev, name: "sdw:%01x:%04x:%04x:%02x",
44 bus->link_id, id->mfg_id, id->part_id,
45 id->class_id);
46 } else {
47 /* name shall be sdw:link:mfg:part:class:unique */
48 dev_set_name(dev: &slave->dev, name: "sdw:%01x:%04x:%04x:%02x:%01x",
49 bus->link_id, id->mfg_id, id->part_id,
50 id->class_id, id->unique_id);
51 }
52
53 slave->dev.bus = &sdw_bus_type;
54 slave->dev.of_node = of_node_get(to_of_node(fwnode));
55 slave->dev.type = &sdw_slave_type;
56 slave->dev.groups = sdw_slave_status_attr_groups;
57 slave->bus = bus;
58 slave->status = SDW_SLAVE_UNATTACHED;
59 init_completion(x: &slave->enumeration_complete);
60 init_completion(x: &slave->initialization_complete);
61 slave->dev_num = 0;
62 slave->probed = false;
63 slave->first_interrupt_done = false;
64 mutex_init(&slave->sdw_dev_lock);
65
66 for (i = 0; i < SDW_MAX_PORTS; i++)
67 init_completion(x: &slave->port_ready[i]);
68
69 mutex_lock(&bus->bus_lock);
70 list_add_tail(new: &slave->node, head: &bus->slaves);
71 mutex_unlock(lock: &bus->bus_lock);
72
73 ret = device_register(dev: &slave->dev);
74 if (ret) {
75 dev_err(bus->dev, "Failed to add slave: ret %d\n", ret);
76
77 /*
78 * On err, don't free but drop ref as this will be freed
79 * when release method is invoked.
80 */
81 mutex_lock(&bus->bus_lock);
82 list_del(entry: &slave->node);
83 mutex_unlock(lock: &bus->bus_lock);
84 put_device(dev: &slave->dev);
85
86 return ret;
87 }
88 sdw_slave_debugfs_init(slave);
89
90 return ret;
91}
92EXPORT_SYMBOL(sdw_slave_add);
93
94#if IS_ENABLED(CONFIG_ACPI)
95
96static bool find_slave(struct sdw_bus *bus,
97 struct acpi_device *adev,
98 struct sdw_slave_id *id)
99{
100 u64 addr;
101 unsigned int link_id;
102 acpi_status status;
103
104 status = acpi_evaluate_integer(handle: adev->handle,
105 METHOD_NAME__ADR, NULL, data: &addr);
106
107 if (ACPI_FAILURE(status)) {
108 dev_err(bus->dev, "_ADR resolution failed: %x\n",
109 status);
110 return false;
111 }
112
113 if (bus->ops->override_adr)
114 addr = bus->ops->override_adr(bus, addr);
115
116 if (!addr)
117 return false;
118
119 /* Extract link id from ADR, Bit 51 to 48 (included) */
120 link_id = SDW_DISCO_LINK_ID(addr);
121
122 /* Check for link_id match */
123 if (link_id != bus->link_id)
124 return false;
125
126 sdw_extract_slave_id(bus, addr, id);
127
128 return true;
129}
130
131struct sdw_acpi_child_walk_data {
132 struct sdw_bus *bus;
133 struct acpi_device *adev;
134 struct sdw_slave_id id;
135 bool ignore_unique_id;
136};
137
138static int sdw_acpi_check_duplicate(struct acpi_device *adev, void *data)
139{
140 struct sdw_acpi_child_walk_data *cwd = data;
141 struct sdw_bus *bus = cwd->bus;
142 struct sdw_slave_id id;
143
144 if (adev == cwd->adev)
145 return 0;
146
147 if (!find_slave(bus, adev, id: &id))
148 return 0;
149
150 if (cwd->id.sdw_version != id.sdw_version || cwd->id.mfg_id != id.mfg_id ||
151 cwd->id.part_id != id.part_id || cwd->id.class_id != id.class_id)
152 return 0;
153
154 if (cwd->id.unique_id != id.unique_id) {
155 dev_dbg(bus->dev,
156 "Valid unique IDs 0x%x 0x%x for Slave mfg_id 0x%04x, part_id 0x%04x\n",
157 cwd->id.unique_id, id.unique_id, cwd->id.mfg_id,
158 cwd->id.part_id);
159 cwd->ignore_unique_id = false;
160 return 0;
161 }
162
163 dev_err(bus->dev,
164 "Invalid unique IDs 0x%x 0x%x for Slave mfg_id 0x%04x, part_id 0x%04x\n",
165 cwd->id.unique_id, id.unique_id, cwd->id.mfg_id, cwd->id.part_id);
166 return -ENODEV;
167}
168
169static int sdw_acpi_find_one(struct acpi_device *adev, void *data)
170{
171 struct sdw_bus *bus = data;
172 struct sdw_acpi_child_walk_data cwd = {
173 .bus = bus,
174 .adev = adev,
175 .ignore_unique_id = true,
176 };
177 int ret;
178
179 if (!find_slave(bus, adev, id: &cwd.id))
180 return 0;
181
182 /* Brute-force O(N^2) search for duplicates. */
183 ret = acpi_dev_for_each_child(ACPI_COMPANION(bus->dev),
184 fn: sdw_acpi_check_duplicate, data: &cwd);
185 if (ret)
186 return ret;
187
188 if (cwd.ignore_unique_id)
189 cwd.id.unique_id = SDW_IGNORED_UNIQUE_ID;
190
191 /* Ignore errors and continue. */
192 sdw_slave_add(bus, &cwd.id, acpi_fwnode_handle(adev));
193 return 0;
194}
195
196/*
197 * sdw_acpi_find_slaves() - Find Slave devices in Master ACPI node
198 * @bus: SDW bus instance
199 *
200 * Scans Master ACPI node for SDW child Slave devices and registers it.
201 */
202int sdw_acpi_find_slaves(struct sdw_bus *bus)
203{
204 struct acpi_device *parent;
205
206 parent = ACPI_COMPANION(bus->dev);
207 if (!parent) {
208 dev_err(bus->dev, "Can't find parent for acpi bind\n");
209 return -ENODEV;
210 }
211
212 return acpi_dev_for_each_child(adev: parent, fn: sdw_acpi_find_one, data: bus);
213}
214
215#endif
216
217/*
218 * sdw_of_find_slaves() - Find Slave devices in master device tree node
219 * @bus: SDW bus instance
220 *
221 * Scans Master DT node for SDW child Slave devices and registers it.
222 */
223int sdw_of_find_slaves(struct sdw_bus *bus)
224{
225 struct device *dev = bus->dev;
226 struct device_node *node;
227
228 for_each_child_of_node(bus->dev->of_node, node) {
229 int link_id, ret, len;
230 unsigned int sdw_version;
231 const char *compat = NULL;
232 struct sdw_slave_id id;
233 const __be32 *addr;
234
235 compat = of_get_property(node, name: "compatible", NULL);
236 if (!compat)
237 continue;
238
239 ret = sscanf(compat, "sdw%01x%04hx%04hx%02hhx", &sdw_version,
240 &id.mfg_id, &id.part_id, &id.class_id);
241
242 if (ret != 4) {
243 dev_err(dev, "Invalid compatible string found %s\n",
244 compat);
245 continue;
246 }
247
248 addr = of_get_property(node, name: "reg", lenp: &len);
249 if (!addr || (len < 2 * sizeof(u32))) {
250 dev_err(dev, "Invalid Link and Instance ID\n");
251 continue;
252 }
253
254 link_id = be32_to_cpup(p: addr++);
255 id.unique_id = be32_to_cpup(p: addr);
256 id.sdw_version = sdw_version;
257
258 /* Check for link_id match */
259 if (link_id != bus->link_id)
260 continue;
261
262 sdw_slave_add(bus, &id, of_fwnode_handle(node));
263 }
264
265 return 0;
266}
267

source code of linux/drivers/soundwire/slave.c