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 /* name shall be sdw:link:mfg:part:class:unique */
33 dev_set_name(&slave->dev, "sdw:%x:%x:%x:%x:%x",
34 bus->link_id, id->mfg_id, id->part_id,
35 id->class_id, id->unique_id);
37 slave->dev.release = sdw_slave_release;
38 slave->dev.bus = &sdw_bus_type;
39 slave->dev.of_node = of_node_get(to_of_node(fwnode));
41 slave->status = SDW_SLAVE_UNATTACHED;
44 mutex_lock(&bus->bus_lock);
45 list_add_tail(&slave->node, &bus->slaves);
46 mutex_unlock(&bus->bus_lock);
48 ret = device_register(&slave->dev);
50 dev_err(bus->dev, "Failed to add slave: ret %d\n", ret);
53 * On err, don't free but drop ref as this will be freed
54 * when release method is invoked.
56 mutex_lock(&bus->bus_lock);
57 list_del(&slave->node);
58 mutex_unlock(&bus->bus_lock);
59 put_device(&slave->dev);
61 sdw_slave_debugfs_init(slave);
66 #if IS_ENABLED(CONFIG_ACPI)
68 * sdw_acpi_find_slaves() - Find Slave devices in Master ACPI node
69 * @bus: SDW bus instance
71 * Scans Master ACPI node for SDW child Slave devices and registers it.
73 int sdw_acpi_find_slaves(struct sdw_bus *bus)
75 struct acpi_device *adev, *parent;
77 parent = ACPI_COMPANION(bus->dev);
79 dev_err(bus->dev, "Can't find parent for acpi bind\n");
83 list_for_each_entry(adev, &parent->children, node) {
84 unsigned long long addr;
85 struct sdw_slave_id id;
89 status = acpi_evaluate_integer(adev->handle,
90 METHOD_NAME__ADR, NULL, &addr);
92 if (ACPI_FAILURE(status)) {
93 dev_err(bus->dev, "_ADR resolution failed: %x\n",
98 /* Extract link id from ADR, Bit 51 to 48 (included) */
99 link_id = (addr >> 48) & GENMASK(3, 0);
101 /* Check for link_id match */
102 if (link_id != bus->link_id)
105 sdw_extract_slave_id(bus, addr, &id);
108 * don't error check for sdw_slave_add as we want to continue
111 sdw_slave_add(bus, &id, acpi_fwnode_handle(adev));
120 * sdw_of_find_slaves() - Find Slave devices in master device tree node
121 * @bus: SDW bus instance
123 * Scans Master DT node for SDW child Slave devices and registers it.
125 int sdw_of_find_slaves(struct sdw_bus *bus)
127 struct device *dev = bus->dev;
128 struct device_node *node;
130 for_each_child_of_node(bus->dev->of_node, node) {
131 int link_id, sdw_version, ret, len;
132 const char *compat = NULL;
133 struct sdw_slave_id id;
136 compat = of_get_property(node, "compatible", NULL);
140 ret = sscanf(compat, "sdw%01x%04hx%04hx%02hhx", &sdw_version,
141 &id.mfg_id, &id.part_id, &id.class_id);
144 dev_err(dev, "Invalid compatible string found %s\n",
149 addr = of_get_property(node, "reg", &len);
150 if (!addr || (len < 2 * sizeof(u32))) {
151 dev_err(dev, "Invalid Link and Instance ID\n");
155 link_id = be32_to_cpup(addr++);
156 id.unique_id = be32_to_cpup(addr);
157 id.sdw_version = sdw_version;
159 /* Check for link_id match */
160 if (link_id != bus->link_id)
163 sdw_slave_add(bus, &id, of_fwnode_handle(node));