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 struct device_type sdw_slave_type = { 18 .name = "sdw_slave", 19 .release = sdw_slave_release, 20 .uevent = sdw_slave_uevent, 21 }; 22 23 static int sdw_slave_add(struct sdw_bus *bus, 24 struct sdw_slave_id *id, struct fwnode_handle *fwnode) 25 { 26 struct sdw_slave *slave; 27 int ret; 28 29 slave = kzalloc(sizeof(*slave), GFP_KERNEL); 30 if (!slave) 31 return -ENOMEM; 32 33 /* Initialize data structure */ 34 memcpy(&slave->id, id, sizeof(*id)); 35 slave->dev.parent = bus->dev; 36 slave->dev.fwnode = fwnode; 37 38 if (id->unique_id == SDW_IGNORED_UNIQUE_ID) { 39 /* name shall be sdw:link:mfg:part:class */ 40 dev_set_name(&slave->dev, "sdw:%x:%x:%x:%x", 41 bus->link_id, id->mfg_id, id->part_id, 42 id->class_id); 43 } else { 44 /* name shall be sdw:link:mfg:part:class:unique */ 45 dev_set_name(&slave->dev, "sdw:%x:%x:%x:%x:%x", 46 bus->link_id, id->mfg_id, id->part_id, 47 id->class_id, id->unique_id); 48 } 49 50 slave->dev.bus = &sdw_bus_type; 51 slave->dev.of_node = of_node_get(to_of_node(fwnode)); 52 slave->dev.type = &sdw_slave_type; 53 slave->bus = bus; 54 slave->status = SDW_SLAVE_UNATTACHED; 55 init_completion(&slave->enumeration_complete); 56 init_completion(&slave->initialization_complete); 57 slave->dev_num = 0; 58 init_completion(&slave->probe_complete); 59 slave->probed = false; 60 61 mutex_lock(&bus->bus_lock); 62 list_add_tail(&slave->node, &bus->slaves); 63 mutex_unlock(&bus->bus_lock); 64 65 ret = device_register(&slave->dev); 66 if (ret) { 67 dev_err(bus->dev, "Failed to add slave: ret %d\n", ret); 68 69 /* 70 * On err, don't free but drop ref as this will be freed 71 * when release method is invoked. 72 */ 73 mutex_lock(&bus->bus_lock); 74 list_del(&slave->node); 75 mutex_unlock(&bus->bus_lock); 76 put_device(&slave->dev); 77 78 return ret; 79 } 80 sdw_slave_debugfs_init(slave); 81 82 return ret; 83 } 84 85 #if IS_ENABLED(CONFIG_ACPI) 86 87 static bool find_slave(struct sdw_bus *bus, 88 struct acpi_device *adev, 89 struct sdw_slave_id *id) 90 { 91 unsigned long long addr; 92 unsigned int link_id; 93 acpi_status status; 94 95 status = acpi_evaluate_integer(adev->handle, 96 METHOD_NAME__ADR, NULL, &addr); 97 98 if (ACPI_FAILURE(status)) { 99 dev_err(bus->dev, "_ADR resolution failed: %x\n", 100 status); 101 return false; 102 } 103 104 /* Extract link id from ADR, Bit 51 to 48 (included) */ 105 link_id = (addr >> 48) & GENMASK(3, 0); 106 107 /* Check for link_id match */ 108 if (link_id != bus->link_id) 109 return false; 110 111 sdw_extract_slave_id(bus, addr, id); 112 113 return true; 114 } 115 116 /* 117 * sdw_acpi_find_slaves() - Find Slave devices in Master ACPI node 118 * @bus: SDW bus instance 119 * 120 * Scans Master ACPI node for SDW child Slave devices and registers it. 121 */ 122 int sdw_acpi_find_slaves(struct sdw_bus *bus) 123 { 124 struct acpi_device *adev, *parent; 125 struct acpi_device *adev2, *parent2; 126 127 parent = ACPI_COMPANION(bus->dev); 128 if (!parent) { 129 dev_err(bus->dev, "Can't find parent for acpi bind\n"); 130 return -ENODEV; 131 } 132 133 list_for_each_entry(adev, &parent->children, node) { 134 struct sdw_slave_id id; 135 struct sdw_slave_id id2; 136 bool ignore_unique_id = true; 137 138 if (!find_slave(bus, adev, &id)) 139 continue; 140 141 /* brute-force O(N^2) search for duplicates */ 142 parent2 = parent; 143 list_for_each_entry(adev2, &parent2->children, node) { 144 145 if (adev == adev2) 146 continue; 147 148 if (!find_slave(bus, adev2, &id2)) 149 continue; 150 151 if (id.sdw_version != id2.sdw_version || 152 id.mfg_id != id2.mfg_id || 153 id.part_id != id2.part_id || 154 id.class_id != id2.class_id) 155 continue; 156 157 if (id.unique_id != id2.unique_id) { 158 dev_dbg(bus->dev, 159 "Valid unique IDs %x %x for Slave mfg %x part %d\n", 160 id.unique_id, id2.unique_id, 161 id.mfg_id, id.part_id); 162 ignore_unique_id = false; 163 } else { 164 dev_err(bus->dev, 165 "Invalid unique IDs %x %x for Slave mfg %x part %d\n", 166 id.unique_id, id2.unique_id, 167 id.mfg_id, id.part_id); 168 return -ENODEV; 169 } 170 } 171 172 if (ignore_unique_id) 173 id.unique_id = SDW_IGNORED_UNIQUE_ID; 174 175 /* 176 * don't error check for sdw_slave_add as we want to continue 177 * adding Slaves 178 */ 179 sdw_slave_add(bus, &id, acpi_fwnode_handle(adev)); 180 } 181 182 return 0; 183 } 184 185 #endif 186 187 /* 188 * sdw_of_find_slaves() - Find Slave devices in master device tree node 189 * @bus: SDW bus instance 190 * 191 * Scans Master DT node for SDW child Slave devices and registers it. 192 */ 193 int sdw_of_find_slaves(struct sdw_bus *bus) 194 { 195 struct device *dev = bus->dev; 196 struct device_node *node; 197 198 for_each_child_of_node(bus->dev->of_node, node) { 199 int link_id, ret, len; 200 unsigned int sdw_version; 201 const char *compat = NULL; 202 struct sdw_slave_id id; 203 const __be32 *addr; 204 205 compat = of_get_property(node, "compatible", NULL); 206 if (!compat) 207 continue; 208 209 ret = sscanf(compat, "sdw%01x%04hx%04hx%02hhx", &sdw_version, 210 &id.mfg_id, &id.part_id, &id.class_id); 211 212 if (ret != 4) { 213 dev_err(dev, "Invalid compatible string found %s\n", 214 compat); 215 continue; 216 } 217 218 addr = of_get_property(node, "reg", &len); 219 if (!addr || (len < 2 * sizeof(u32))) { 220 dev_err(dev, "Invalid Link and Instance ID\n"); 221 continue; 222 } 223 224 link_id = be32_to_cpup(addr++); 225 id.unique_id = be32_to_cpup(addr); 226 id.sdw_version = sdw_version; 227 228 /* Check for link_id match */ 229 if (link_id != bus->link_id) 230 continue; 231 232 sdw_slave_add(bus, &id, of_fwnode_handle(node)); 233 } 234 235 return 0; 236 } 237