1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Greybus "Core" 4 * 5 * Copyright 2014-2015 Google Inc. 6 * Copyright 2014-2015 Linaro Ltd. 7 */ 8 9 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 10 11 #define CREATE_TRACE_POINTS 12 #include <linux/greybus.h> 13 #include "greybus_trace.h" 14 15 #define GB_BUNDLE_AUTOSUSPEND_MS 3000 16 17 /* Allow greybus to be disabled at boot if needed */ 18 static bool nogreybus; 19 #ifdef MODULE 20 module_param(nogreybus, bool, 0444); 21 #else 22 core_param(nogreybus, nogreybus, bool, 0444); 23 #endif 24 int greybus_disabled(void) 25 { 26 return nogreybus; 27 } 28 EXPORT_SYMBOL_GPL(greybus_disabled); 29 30 static bool greybus_match_one_id(struct gb_bundle *bundle, 31 const struct greybus_bundle_id *id) 32 { 33 if ((id->match_flags & GREYBUS_ID_MATCH_VENDOR) && 34 (id->vendor != bundle->intf->vendor_id)) 35 return false; 36 37 if ((id->match_flags & GREYBUS_ID_MATCH_PRODUCT) && 38 (id->product != bundle->intf->product_id)) 39 return false; 40 41 if ((id->match_flags & GREYBUS_ID_MATCH_CLASS) && 42 (id->class != bundle->class)) 43 return false; 44 45 return true; 46 } 47 48 static const struct greybus_bundle_id * 49 greybus_match_id(struct gb_bundle *bundle, const struct greybus_bundle_id *id) 50 { 51 if (!id) 52 return NULL; 53 54 for (; id->vendor || id->product || id->class || id->driver_info; 55 id++) { 56 if (greybus_match_one_id(bundle, id)) 57 return id; 58 } 59 60 return NULL; 61 } 62 63 static int greybus_match_device(struct device *dev, struct device_driver *drv) 64 { 65 struct greybus_driver *driver = to_greybus_driver(drv); 66 struct gb_bundle *bundle; 67 const struct greybus_bundle_id *id; 68 69 if (!is_gb_bundle(dev)) 70 return 0; 71 72 bundle = to_gb_bundle(dev); 73 74 id = greybus_match_id(bundle, driver->id_table); 75 if (id) 76 return 1; 77 /* FIXME - Dynamic ids? */ 78 return 0; 79 } 80 81 static int greybus_uevent(const struct device *dev, struct kobj_uevent_env *env) 82 { 83 const struct gb_host_device *hd; 84 const struct gb_module *module = NULL; 85 const struct gb_interface *intf = NULL; 86 const struct gb_control *control = NULL; 87 const struct gb_bundle *bundle = NULL; 88 const struct gb_svc *svc = NULL; 89 90 if (is_gb_host_device(dev)) { 91 hd = to_gb_host_device(dev); 92 } else if (is_gb_module(dev)) { 93 module = to_gb_module(dev); 94 hd = module->hd; 95 } else if (is_gb_interface(dev)) { 96 intf = to_gb_interface(dev); 97 module = intf->module; 98 hd = intf->hd; 99 } else if (is_gb_control(dev)) { 100 control = to_gb_control(dev); 101 intf = control->intf; 102 module = intf->module; 103 hd = intf->hd; 104 } else if (is_gb_bundle(dev)) { 105 bundle = to_gb_bundle(dev); 106 intf = bundle->intf; 107 module = intf->module; 108 hd = intf->hd; 109 } else if (is_gb_svc(dev)) { 110 svc = to_gb_svc(dev); 111 hd = svc->hd; 112 } else { 113 dev_WARN(dev, "uevent for unknown greybus device \"type\"!\n"); 114 return -EINVAL; 115 } 116 117 if (add_uevent_var(env, "BUS=%u", hd->bus_id)) 118 return -ENOMEM; 119 120 if (module) { 121 if (add_uevent_var(env, "MODULE=%u", module->module_id)) 122 return -ENOMEM; 123 } 124 125 if (intf) { 126 if (add_uevent_var(env, "INTERFACE=%u", intf->interface_id)) 127 return -ENOMEM; 128 if (add_uevent_var(env, "GREYBUS_ID=%08x/%08x", 129 intf->vendor_id, intf->product_id)) 130 return -ENOMEM; 131 } 132 133 if (bundle) { 134 // FIXME 135 // add a uevent that can "load" a bundle type 136 // This is what we need to bind a driver to so use the info 137 // in gmod here as well 138 139 if (add_uevent_var(env, "BUNDLE=%u", bundle->id)) 140 return -ENOMEM; 141 if (add_uevent_var(env, "BUNDLE_CLASS=%02x", bundle->class)) 142 return -ENOMEM; 143 } 144 145 return 0; 146 } 147 148 static void greybus_shutdown(struct device *dev) 149 { 150 if (is_gb_host_device(dev)) { 151 struct gb_host_device *hd; 152 153 hd = to_gb_host_device(dev); 154 gb_hd_shutdown(hd); 155 } 156 } 157 158 struct bus_type greybus_bus_type = { 159 .name = "greybus", 160 .match = greybus_match_device, 161 .uevent = greybus_uevent, 162 .shutdown = greybus_shutdown, 163 }; 164 165 static int greybus_probe(struct device *dev) 166 { 167 struct greybus_driver *driver = to_greybus_driver(dev->driver); 168 struct gb_bundle *bundle = to_gb_bundle(dev); 169 const struct greybus_bundle_id *id; 170 int retval; 171 172 /* match id */ 173 id = greybus_match_id(bundle, driver->id_table); 174 if (!id) 175 return -ENODEV; 176 177 retval = pm_runtime_get_sync(&bundle->intf->dev); 178 if (retval < 0) { 179 pm_runtime_put_noidle(&bundle->intf->dev); 180 return retval; 181 } 182 183 retval = gb_control_bundle_activate(bundle->intf->control, bundle->id); 184 if (retval) { 185 pm_runtime_put(&bundle->intf->dev); 186 return retval; 187 } 188 189 /* 190 * Unbound bundle devices are always deactivated. During probe, the 191 * Runtime PM is set to enabled and active and the usage count is 192 * incremented. If the driver supports runtime PM, it should call 193 * pm_runtime_put() in its probe routine and pm_runtime_get_sync() 194 * in remove routine. 195 */ 196 pm_runtime_set_autosuspend_delay(dev, GB_BUNDLE_AUTOSUSPEND_MS); 197 pm_runtime_use_autosuspend(dev); 198 pm_runtime_get_noresume(dev); 199 pm_runtime_set_active(dev); 200 pm_runtime_enable(dev); 201 202 retval = driver->probe(bundle, id); 203 if (retval) { 204 /* 205 * Catch buggy drivers that fail to destroy their connections. 206 */ 207 WARN_ON(!list_empty(&bundle->connections)); 208 209 gb_control_bundle_deactivate(bundle->intf->control, bundle->id); 210 211 pm_runtime_disable(dev); 212 pm_runtime_set_suspended(dev); 213 pm_runtime_put_noidle(dev); 214 pm_runtime_dont_use_autosuspend(dev); 215 pm_runtime_put(&bundle->intf->dev); 216 217 return retval; 218 } 219 220 pm_runtime_put(&bundle->intf->dev); 221 222 return 0; 223 } 224 225 static int greybus_remove(struct device *dev) 226 { 227 struct greybus_driver *driver = to_greybus_driver(dev->driver); 228 struct gb_bundle *bundle = to_gb_bundle(dev); 229 struct gb_connection *connection; 230 int retval; 231 232 retval = pm_runtime_get_sync(dev); 233 if (retval < 0) 234 dev_err(dev, "failed to resume bundle: %d\n", retval); 235 236 /* 237 * Disable (non-offloaded) connections early in case the interface is 238 * already gone to avoid unceccessary operation timeouts during 239 * driver disconnect. Otherwise, only disable incoming requests. 240 */ 241 list_for_each_entry(connection, &bundle->connections, bundle_links) { 242 if (gb_connection_is_offloaded(connection)) 243 continue; 244 245 if (bundle->intf->disconnected) 246 gb_connection_disable_forced(connection); 247 else 248 gb_connection_disable_rx(connection); 249 } 250 251 driver->disconnect(bundle); 252 253 /* Catch buggy drivers that fail to destroy their connections. */ 254 WARN_ON(!list_empty(&bundle->connections)); 255 256 if (!bundle->intf->disconnected) 257 gb_control_bundle_deactivate(bundle->intf->control, bundle->id); 258 259 pm_runtime_put_noidle(dev); 260 pm_runtime_disable(dev); 261 pm_runtime_set_suspended(dev); 262 pm_runtime_dont_use_autosuspend(dev); 263 pm_runtime_put_noidle(dev); 264 265 return 0; 266 } 267 268 int greybus_register_driver(struct greybus_driver *driver, struct module *owner, 269 const char *mod_name) 270 { 271 int retval; 272 273 if (greybus_disabled()) 274 return -ENODEV; 275 276 driver->driver.bus = &greybus_bus_type; 277 driver->driver.name = driver->name; 278 driver->driver.probe = greybus_probe; 279 driver->driver.remove = greybus_remove; 280 driver->driver.owner = owner; 281 driver->driver.mod_name = mod_name; 282 283 retval = driver_register(&driver->driver); 284 if (retval) 285 return retval; 286 287 pr_info("registered new driver %s\n", driver->name); 288 return 0; 289 } 290 EXPORT_SYMBOL_GPL(greybus_register_driver); 291 292 void greybus_deregister_driver(struct greybus_driver *driver) 293 { 294 driver_unregister(&driver->driver); 295 } 296 EXPORT_SYMBOL_GPL(greybus_deregister_driver); 297 298 static int __init gb_init(void) 299 { 300 int retval; 301 302 if (greybus_disabled()) 303 return -ENODEV; 304 305 BUILD_BUG_ON(CPORT_ID_MAX >= (long)CPORT_ID_BAD); 306 307 gb_debugfs_init(); 308 309 retval = bus_register(&greybus_bus_type); 310 if (retval) { 311 pr_err("bus_register failed (%d)\n", retval); 312 goto error_bus; 313 } 314 315 retval = gb_hd_init(); 316 if (retval) { 317 pr_err("gb_hd_init failed (%d)\n", retval); 318 goto error_hd; 319 } 320 321 retval = gb_operation_init(); 322 if (retval) { 323 pr_err("gb_operation_init failed (%d)\n", retval); 324 goto error_operation; 325 } 326 return 0; /* Success */ 327 328 error_operation: 329 gb_hd_exit(); 330 error_hd: 331 bus_unregister(&greybus_bus_type); 332 error_bus: 333 gb_debugfs_cleanup(); 334 335 return retval; 336 } 337 module_init(gb_init); 338 339 static void __exit gb_exit(void) 340 { 341 gb_operation_exit(); 342 gb_hd_exit(); 343 bus_unregister(&greybus_bus_type); 344 gb_debugfs_cleanup(); 345 tracepoint_synchronize_unregister(); 346 } 347 module_exit(gb_exit); 348 MODULE_LICENSE("GPL v2"); 349 MODULE_AUTHOR("Greg Kroah-Hartman <gregkh@linuxfoundation.org>"); 350