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 kfree(slave);
16 }
17
18 struct device_type sdw_slave_type = {
19 .name = "sdw_slave",
20 .release = sdw_slave_release,
21 .uevent = sdw_slave_uevent,
22 };
23
sdw_slave_add(struct sdw_bus * bus,struct sdw_slave_id * id,struct fwnode_handle * fwnode)24 int 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
find_slave(struct sdw_bus * bus,struct acpi_device * adev,struct sdw_slave_id * id)94 static 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 */
sdw_acpi_find_slaves(struct sdw_bus * bus)129 int 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 */
sdw_of_find_slaves(struct sdw_bus * bus)200 int 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