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