1 // SPDX-License-Identifier: (GPL-2.0 OR BSD-3-Clause)
2 // Copyright(c) 2015-17 Intel Corporation.
4 #include <linux/acpi.h>
6 #include <linux/soundwire/sdw.h>
7 #include <linux/soundwire/sdw_type.h>
10 static void sdw_slave_release(struct device *dev)
12 struct sdw_slave *slave = dev_to_sdw_dev(dev);
17 static int sdw_slave_add(struct sdw_bus *bus,
18 struct sdw_slave_id *id, struct fwnode_handle *fwnode)
20 struct sdw_slave *slave;
23 slave = kzalloc(sizeof(*slave), GFP_KERNEL);
27 /* Initialize data structure */
28 memcpy(&slave->id, id, sizeof(*id));
29 slave->dev.parent = bus->dev;
30 slave->dev.fwnode = fwnode;
32 if (id->unique_id == SDW_IGNORED_UNIQUE_ID) {
33 /* name shall be sdw:link:mfg:part:class */
34 dev_set_name(&slave->dev, "sdw:%x:%x:%x:%x",
35 bus->link_id, id->mfg_id, id->part_id,
38 /* name shall be sdw:link:mfg:part:class:unique */
39 dev_set_name(&slave->dev, "sdw:%x:%x:%x:%x:%x",
40 bus->link_id, id->mfg_id, id->part_id,
41 id->class_id, id->unique_id);
44 slave->dev.release = sdw_slave_release;
45 slave->dev.bus = &sdw_bus_type;
46 slave->dev.of_node = of_node_get(to_of_node(fwnode));
48 slave->status = SDW_SLAVE_UNATTACHED;
49 init_completion(&slave->enumeration_complete);
50 init_completion(&slave->initialization_complete);
52 init_completion(&slave->probe_complete);
53 slave->probed = false;
55 mutex_lock(&bus->bus_lock);
56 list_add_tail(&slave->node, &bus->slaves);
57 mutex_unlock(&bus->bus_lock);
59 ret = device_register(&slave->dev);
61 dev_err(bus->dev, "Failed to add slave: ret %d\n", ret);
64 * On err, don't free but drop ref as this will be freed
65 * when release method is invoked.
67 mutex_lock(&bus->bus_lock);
68 list_del(&slave->node);
69 mutex_unlock(&bus->bus_lock);
70 put_device(&slave->dev);
72 sdw_slave_debugfs_init(slave);
77 #if IS_ENABLED(CONFIG_ACPI)
79 static bool find_slave(struct sdw_bus *bus,
80 struct acpi_device *adev,
81 struct sdw_slave_id *id)
83 unsigned long long addr;
87 status = acpi_evaluate_integer(adev->handle,
88 METHOD_NAME__ADR, NULL, &addr);
90 if (ACPI_FAILURE(status)) {
91 dev_err(bus->dev, "_ADR resolution failed: %x\n",
96 /* Extract link id from ADR, Bit 51 to 48 (included) */
97 link_id = (addr >> 48) & GENMASK(3, 0);
99 /* Check for link_id match */
100 if (link_id != bus->link_id)
103 sdw_extract_slave_id(bus, addr, id);
109 * sdw_acpi_find_slaves() - Find Slave devices in Master ACPI node
110 * @bus: SDW bus instance
112 * Scans Master ACPI node for SDW child Slave devices and registers it.
114 int sdw_acpi_find_slaves(struct sdw_bus *bus)
116 struct acpi_device *adev, *parent;
117 struct acpi_device *adev2, *parent2;
119 parent = ACPI_COMPANION(bus->dev);
121 dev_err(bus->dev, "Can't find parent for acpi bind\n");
125 list_for_each_entry(adev, &parent->children, node) {
126 struct sdw_slave_id id;
127 struct sdw_slave_id id2;
128 bool ignore_unique_id = true;
130 if (!find_slave(bus, adev, &id))
133 /* brute-force O(N^2) search for duplicates */
135 list_for_each_entry(adev2, &parent2->children, node) {
140 if (!find_slave(bus, adev2, &id2))
143 if (id.sdw_version != id2.sdw_version ||
144 id.mfg_id != id2.mfg_id ||
145 id.part_id != id2.part_id ||
146 id.class_id != id2.class_id)
149 if (id.unique_id != id2.unique_id) {
151 "Valid unique IDs %x %x for Slave mfg %x part %d\n",
152 id.unique_id, id2.unique_id,
153 id.mfg_id, id.part_id);
154 ignore_unique_id = false;
157 "Invalid unique IDs %x %x for Slave mfg %x part %d\n",
158 id.unique_id, id2.unique_id,
159 id.mfg_id, id.part_id);
164 if (ignore_unique_id)
165 id.unique_id = SDW_IGNORED_UNIQUE_ID;
168 * don't error check for sdw_slave_add as we want to continue
171 sdw_slave_add(bus, &id, acpi_fwnode_handle(adev));
180 * sdw_of_find_slaves() - Find Slave devices in master device tree node
181 * @bus: SDW bus instance
183 * Scans Master DT node for SDW child Slave devices and registers it.
185 int sdw_of_find_slaves(struct sdw_bus *bus)
187 struct device *dev = bus->dev;
188 struct device_node *node;
190 for_each_child_of_node(bus->dev->of_node, node) {
191 int link_id, ret, len;
192 unsigned int sdw_version;
193 const char *compat = NULL;
194 struct sdw_slave_id id;
197 compat = of_get_property(node, "compatible", NULL);
201 ret = sscanf(compat, "sdw%01x%04hx%04hx%02hhx", &sdw_version,
202 &id.mfg_id, &id.part_id, &id.class_id);
205 dev_err(dev, "Invalid compatible string found %s\n",
210 addr = of_get_property(node, "reg", &len);
211 if (!addr || (len < 2 * sizeof(u32))) {
212 dev_err(dev, "Invalid Link and Instance ID\n");
216 link_id = be32_to_cpup(addr++);
217 id.unique_id = be32_to_cpup(addr);
218 id.sdw_version = sdw_version;
220 /* Check for link_id match */
221 if (link_id != bus->link_id)
224 sdw_slave_add(bus, &id, of_fwnode_handle(node));