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 10 static void sdw_slave_release(struct device *dev) 11 { 12 struct sdw_slave *slave = dev_to_sdw_dev(dev); 13 14 kfree(slave); 15 } 16 17 static int sdw_slave_add(struct sdw_bus *bus, 18 struct sdw_slave_id *id, struct fwnode_handle *fwnode) 19 { 20 struct sdw_slave *slave; 21 int ret; 22 23 slave = kzalloc(sizeof(*slave), GFP_KERNEL); 24 if (!slave) 25 return -ENOMEM; 26 27 /* Initialize data structure */ 28 memcpy(&slave->id, id, sizeof(*id)); 29 slave->dev.parent = bus->dev; 30 slave->dev.fwnode = fwnode; 31 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, 36 id->class_id); 37 } else { 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); 42 } 43 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)); 47 slave->bus = bus; 48 slave->status = SDW_SLAVE_UNATTACHED; 49 slave->dev_num = 0; 50 51 mutex_lock(&bus->bus_lock); 52 list_add_tail(&slave->node, &bus->slaves); 53 mutex_unlock(&bus->bus_lock); 54 55 ret = device_register(&slave->dev); 56 if (ret) { 57 dev_err(bus->dev, "Failed to add slave: ret %d\n", ret); 58 59 /* 60 * On err, don't free but drop ref as this will be freed 61 * when release method is invoked. 62 */ 63 mutex_lock(&bus->bus_lock); 64 list_del(&slave->node); 65 mutex_unlock(&bus->bus_lock); 66 put_device(&slave->dev); 67 } 68 sdw_slave_debugfs_init(slave); 69 70 return ret; 71 } 72 73 #if IS_ENABLED(CONFIG_ACPI) 74 75 static bool find_slave(struct sdw_bus *bus, 76 struct acpi_device *adev, 77 struct sdw_slave_id *id) 78 { 79 unsigned long long addr; 80 unsigned int link_id; 81 acpi_status status; 82 83 status = acpi_evaluate_integer(adev->handle, 84 METHOD_NAME__ADR, NULL, &addr); 85 86 if (ACPI_FAILURE(status)) { 87 dev_err(bus->dev, "_ADR resolution failed: %x\n", 88 status); 89 return false; 90 } 91 92 /* Extract link id from ADR, Bit 51 to 48 (included) */ 93 link_id = (addr >> 48) & GENMASK(3, 0); 94 95 /* Check for link_id match */ 96 if (link_id != bus->link_id) 97 return false; 98 99 sdw_extract_slave_id(bus, addr, id); 100 101 return true; 102 } 103 104 /* 105 * sdw_acpi_find_slaves() - Find Slave devices in Master ACPI node 106 * @bus: SDW bus instance 107 * 108 * Scans Master ACPI node for SDW child Slave devices and registers it. 109 */ 110 int sdw_acpi_find_slaves(struct sdw_bus *bus) 111 { 112 struct acpi_device *adev, *parent; 113 struct acpi_device *adev2, *parent2; 114 115 parent = ACPI_COMPANION(bus->dev); 116 if (!parent) { 117 dev_err(bus->dev, "Can't find parent for acpi bind\n"); 118 return -ENODEV; 119 } 120 121 list_for_each_entry(adev, &parent->children, node) { 122 struct sdw_slave_id id; 123 struct sdw_slave_id id2; 124 bool ignore_unique_id = true; 125 126 if (!find_slave(bus, adev, &id)) 127 continue; 128 129 /* brute-force O(N^2) search for duplicates */ 130 parent2 = parent; 131 list_for_each_entry(adev2, &parent2->children, node) { 132 133 if (adev == adev2) 134 continue; 135 136 if (!find_slave(bus, adev2, &id2)) 137 continue; 138 139 if (id.sdw_version != id2.sdw_version || 140 id.mfg_id != id2.mfg_id || 141 id.part_id != id2.part_id || 142 id.class_id != id2.class_id) 143 continue; 144 145 if (id.unique_id != id2.unique_id) { 146 dev_dbg(bus->dev, 147 "Valid unique IDs %x %x for Slave mfg %x part %d\n", 148 id.unique_id, id2.unique_id, 149 id.mfg_id, id.part_id); 150 ignore_unique_id = false; 151 } else { 152 dev_err(bus->dev, 153 "Invalid unique IDs %x %x for Slave mfg %x part %d\n", 154 id.unique_id, id2.unique_id, 155 id.mfg_id, id.part_id); 156 return -ENODEV; 157 } 158 } 159 160 if (ignore_unique_id) 161 id.unique_id = SDW_IGNORED_UNIQUE_ID; 162 163 /* 164 * don't error check for sdw_slave_add as we want to continue 165 * adding Slaves 166 */ 167 sdw_slave_add(bus, &id, acpi_fwnode_handle(adev)); 168 } 169 170 return 0; 171 } 172 173 #endif 174 175 /* 176 * sdw_of_find_slaves() - Find Slave devices in master device tree node 177 * @bus: SDW bus instance 178 * 179 * Scans Master DT node for SDW child Slave devices and registers it. 180 */ 181 int sdw_of_find_slaves(struct sdw_bus *bus) 182 { 183 struct device *dev = bus->dev; 184 struct device_node *node; 185 186 for_each_child_of_node(bus->dev->of_node, node) { 187 int link_id, ret, len; 188 unsigned int sdw_version; 189 const char *compat = NULL; 190 struct sdw_slave_id id; 191 const __be32 *addr; 192 193 compat = of_get_property(node, "compatible", NULL); 194 if (!compat) 195 continue; 196 197 ret = sscanf(compat, "sdw%01x%04hx%04hx%02hhx", &sdw_version, 198 &id.mfg_id, &id.part_id, &id.class_id); 199 200 if (ret != 4) { 201 dev_err(dev, "Invalid compatible string found %s\n", 202 compat); 203 continue; 204 } 205 206 addr = of_get_property(node, "reg", &len); 207 if (!addr || (len < 2 * sizeof(u32))) { 208 dev_err(dev, "Invalid Link and Instance ID\n"); 209 continue; 210 } 211 212 link_id = be32_to_cpup(addr++); 213 id.unique_id = be32_to_cpup(addr); 214 id.sdw_version = sdw_version; 215 216 /* Check for link_id match */ 217 if (link_id != bus->link_id) 218 continue; 219 220 sdw_slave_add(bus, &id, of_fwnode_handle(node)); 221 } 222 223 return 0; 224 } 225