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
sdw_slave_release(struct device * dev)11 static void sdw_slave_release(struct device *dev)
12 {
13 struct sdw_slave *slave = dev_to_sdw_dev(dev);
14
15 of_node_put(slave->dev.of_node);
16 mutex_destroy(&slave->sdw_dev_lock);
17 kfree(slave);
18 }
19
20 struct device_type sdw_slave_type = {
21 .name = "sdw_slave",
22 .release = sdw_slave_release,
23 .uevent = sdw_slave_uevent,
24 };
25
sdw_slave_add(struct sdw_bus * bus,struct sdw_slave_id * id,struct fwnode_handle * fwnode)26 int sdw_slave_add(struct sdw_bus *bus,
27 struct sdw_slave_id *id, struct fwnode_handle *fwnode)
28 {
29 struct sdw_slave *slave;
30 int ret;
31 int i;
32
33 slave = kzalloc(sizeof(*slave), GFP_KERNEL);
34 if (!slave)
35 return -ENOMEM;
36
37 /* Initialize data structure */
38 memcpy(&slave->id, id, sizeof(*id));
39 slave->dev.parent = bus->dev;
40 slave->dev.fwnode = fwnode;
41
42 if (id->unique_id == SDW_IGNORED_UNIQUE_ID) {
43 /* name shall be sdw:ctrl:link:mfg:part:class */
44 dev_set_name(&slave->dev, "sdw:%01x:%01x:%04x:%04x:%02x",
45 bus->controller_id, bus->link_id, id->mfg_id, id->part_id,
46 id->class_id);
47 } else {
48 /* name shall be sdw:ctrl:link:mfg:part:class:unique */
49 dev_set_name(&slave->dev, "sdw:%01x:%01x:%04x:%04x:%02x:%01x",
50 bus->controller_id, bus->link_id, id->mfg_id, id->part_id,
51 id->class_id, id->unique_id);
52 }
53
54 slave->dev.bus = &sdw_bus_type;
55 slave->dev.of_node = of_node_get(to_of_node(fwnode));
56 slave->dev.type = &sdw_slave_type;
57 slave->dev.groups = sdw_slave_status_attr_groups;
58 slave->bus = bus;
59 slave->status = SDW_SLAVE_UNATTACHED;
60 init_completion(&slave->enumeration_complete);
61 init_completion(&slave->initialization_complete);
62 slave->dev_num = 0;
63 slave->probed = false;
64 slave->first_interrupt_done = false;
65 mutex_init(&slave->sdw_dev_lock);
66
67 for (i = 0; i < SDW_MAX_PORTS; i++)
68 init_completion(&slave->port_ready[i]);
69
70 mutex_lock(&bus->bus_lock);
71 list_add_tail(&slave->node, &bus->slaves);
72 mutex_unlock(&bus->bus_lock);
73
74 ret = device_register(&slave->dev);
75 if (ret) {
76 dev_err(bus->dev, "Failed to add slave: ret %d\n", ret);
77
78 /*
79 * On err, don't free but drop ref as this will be freed
80 * when release method is invoked.
81 */
82 mutex_lock(&bus->bus_lock);
83 list_del(&slave->node);
84 mutex_unlock(&bus->bus_lock);
85 put_device(&slave->dev);
86
87 return ret;
88 }
89 sdw_slave_debugfs_init(slave);
90
91 return ret;
92 }
93 EXPORT_SYMBOL(sdw_slave_add);
94
95 #if IS_ENABLED(CONFIG_ACPI)
96
find_slave(struct sdw_bus * bus,struct acpi_device * adev,struct sdw_slave_id * id)97 static bool find_slave(struct sdw_bus *bus,
98 struct acpi_device *adev,
99 struct sdw_slave_id *id)
100 {
101 u64 addr;
102 unsigned int link_id;
103 acpi_status status;
104
105 status = acpi_evaluate_integer(adev->handle,
106 METHOD_NAME__ADR, NULL, &addr);
107
108 if (ACPI_FAILURE(status)) {
109 dev_err(bus->dev, "_ADR resolution failed: %x\n",
110 status);
111 return false;
112 }
113
114 if (bus->ops->override_adr)
115 addr = bus->ops->override_adr(bus, addr);
116
117 if (!addr)
118 return false;
119
120 /* Extract link id from ADR, Bit 51 to 48 (included) */
121 link_id = SDW_DISCO_LINK_ID(addr);
122
123 /* Check for link_id match */
124 if (link_id != bus->link_id)
125 return false;
126
127 sdw_extract_slave_id(bus, addr, id);
128
129 return true;
130 }
131
132 struct sdw_acpi_child_walk_data {
133 struct sdw_bus *bus;
134 struct acpi_device *adev;
135 struct sdw_slave_id id;
136 bool ignore_unique_id;
137 };
138
sdw_acpi_check_duplicate(struct acpi_device * adev,void * data)139 static int sdw_acpi_check_duplicate(struct acpi_device *adev, void *data)
140 {
141 struct sdw_acpi_child_walk_data *cwd = data;
142 struct sdw_bus *bus = cwd->bus;
143 struct sdw_slave_id id;
144
145 if (adev == cwd->adev)
146 return 0;
147
148 if (!find_slave(bus, adev, &id))
149 return 0;
150
151 if (cwd->id.sdw_version != id.sdw_version || cwd->id.mfg_id != id.mfg_id ||
152 cwd->id.part_id != id.part_id || cwd->id.class_id != id.class_id)
153 return 0;
154
155 if (cwd->id.unique_id != id.unique_id) {
156 dev_dbg(bus->dev,
157 "Valid unique IDs 0x%x 0x%x for Slave mfg_id 0x%04x, part_id 0x%04x\n",
158 cwd->id.unique_id, id.unique_id, cwd->id.mfg_id,
159 cwd->id.part_id);
160 cwd->ignore_unique_id = false;
161 return 0;
162 }
163
164 dev_err(bus->dev,
165 "Invalid unique IDs 0x%x 0x%x for Slave mfg_id 0x%04x, part_id 0x%04x\n",
166 cwd->id.unique_id, id.unique_id, cwd->id.mfg_id, cwd->id.part_id);
167 return -ENODEV;
168 }
169
sdw_acpi_find_one(struct acpi_device * adev,void * data)170 static int sdw_acpi_find_one(struct acpi_device *adev, void *data)
171 {
172 struct sdw_bus *bus = data;
173 struct sdw_acpi_child_walk_data cwd = {
174 .bus = bus,
175 .adev = adev,
176 .ignore_unique_id = true,
177 };
178 int ret;
179
180 if (!find_slave(bus, adev, &cwd.id))
181 return 0;
182
183 /* Brute-force O(N^2) search for duplicates. */
184 ret = acpi_dev_for_each_child(ACPI_COMPANION(bus->dev),
185 sdw_acpi_check_duplicate, &cwd);
186 if (ret)
187 return ret;
188
189 if (cwd.ignore_unique_id)
190 cwd.id.unique_id = SDW_IGNORED_UNIQUE_ID;
191
192 /* Ignore errors and continue. */
193 sdw_slave_add(bus, &cwd.id, acpi_fwnode_handle(adev));
194 return 0;
195 }
196
197 /*
198 * sdw_acpi_find_slaves() - Find Slave devices in Master ACPI node
199 * @bus: SDW bus instance
200 *
201 * Scans Master ACPI node for SDW child Slave devices and registers it.
202 */
sdw_acpi_find_slaves(struct sdw_bus * bus)203 int sdw_acpi_find_slaves(struct sdw_bus *bus)
204 {
205 struct acpi_device *parent;
206
207 parent = ACPI_COMPANION(bus->dev);
208 if (!parent) {
209 dev_err(bus->dev, "Can't find parent for acpi bind\n");
210 return -ENODEV;
211 }
212
213 return acpi_dev_for_each_child(parent, sdw_acpi_find_one, bus);
214 }
215
216 #endif
217
218 /*
219 * sdw_of_find_slaves() - Find Slave devices in master device tree node
220 * @bus: SDW bus instance
221 *
222 * Scans Master DT node for SDW child Slave devices and registers it.
223 */
sdw_of_find_slaves(struct sdw_bus * bus)224 int sdw_of_find_slaves(struct sdw_bus *bus)
225 {
226 struct device *dev = bus->dev;
227 struct device_node *node;
228
229 for_each_child_of_node(bus->dev->of_node, node) {
230 int link_id, ret, len;
231 unsigned int sdw_version;
232 const char *compat = NULL;
233 struct sdw_slave_id id;
234 const __be32 *addr;
235
236 compat = of_get_property(node, "compatible", NULL);
237 if (!compat)
238 continue;
239
240 ret = sscanf(compat, "sdw%01x%04hx%04hx%02hhx", &sdw_version,
241 &id.mfg_id, &id.part_id, &id.class_id);
242
243 if (ret != 4) {
244 dev_err(dev, "Invalid compatible string found %s\n",
245 compat);
246 continue;
247 }
248
249 addr = of_get_property(node, "reg", &len);
250 if (!addr || (len < 2 * sizeof(u32))) {
251 dev_err(dev, "Invalid Link and Instance ID\n");
252 continue;
253 }
254
255 link_id = be32_to_cpup(addr++);
256 id.unique_id = be32_to_cpup(addr);
257 id.sdw_version = sdw_version;
258
259 /* Check for link_id match */
260 if (link_id != bus->link_id)
261 continue;
262
263 sdw_slave_add(bus, &id, of_fwnode_handle(node));
264 }
265
266 return 0;
267 }
268