1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Greybus Bridged-Phy Bus driver 4 * 5 * Copyright 2014 Google Inc. 6 * Copyright 2014 Linaro Ltd. 7 */ 8 9 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 10 11 #include <linux/types.h> 12 #include <linux/module.h> 13 #include <linux/kernel.h> 14 #include <linux/slab.h> 15 #include <linux/device.h> 16 #include <linux/greybus.h> 17 18 #include "gbphy.h" 19 20 #define GB_GBPHY_AUTOSUSPEND_MS 3000 21 22 struct gbphy_host { 23 struct gb_bundle *bundle; 24 struct list_head devices; 25 }; 26 27 static DEFINE_IDA(gbphy_id); 28 29 static ssize_t protocol_id_show(struct device *dev, 30 struct device_attribute *attr, char *buf) 31 { 32 struct gbphy_device *gbphy_dev = to_gbphy_dev(dev); 33 34 return sprintf(buf, "0x%02x\n", gbphy_dev->cport_desc->protocol_id); 35 } 36 static DEVICE_ATTR_RO(protocol_id); 37 38 static struct attribute *gbphy_dev_attrs[] = { 39 &dev_attr_protocol_id.attr, 40 NULL, 41 }; 42 43 ATTRIBUTE_GROUPS(gbphy_dev); 44 45 static void gbphy_dev_release(struct device *dev) 46 { 47 struct gbphy_device *gbphy_dev = to_gbphy_dev(dev); 48 49 ida_simple_remove(&gbphy_id, gbphy_dev->id); 50 kfree(gbphy_dev); 51 } 52 53 #ifdef CONFIG_PM 54 static int gb_gbphy_idle(struct device *dev) 55 { 56 pm_runtime_mark_last_busy(dev); 57 pm_request_autosuspend(dev); 58 return 0; 59 } 60 #endif 61 62 static const struct dev_pm_ops gb_gbphy_pm_ops = { 63 SET_RUNTIME_PM_OPS(pm_generic_runtime_suspend, 64 pm_generic_runtime_resume, 65 gb_gbphy_idle) 66 }; 67 68 static const struct device_type greybus_gbphy_dev_type = { 69 .name = "gbphy_device", 70 .release = gbphy_dev_release, 71 .pm = &gb_gbphy_pm_ops, 72 }; 73 74 static int gbphy_dev_uevent(const struct device *dev, struct kobj_uevent_env *env) 75 { 76 const struct gbphy_device *gbphy_dev = to_gbphy_dev(dev); 77 const struct greybus_descriptor_cport *cport_desc = gbphy_dev->cport_desc; 78 const struct gb_bundle *bundle = gbphy_dev->bundle; 79 const struct gb_interface *intf = bundle->intf; 80 const struct gb_module *module = intf->module; 81 const struct gb_host_device *hd = intf->hd; 82 83 if (add_uevent_var(env, "BUS=%u", hd->bus_id)) 84 return -ENOMEM; 85 if (add_uevent_var(env, "MODULE=%u", module->module_id)) 86 return -ENOMEM; 87 if (add_uevent_var(env, "INTERFACE=%u", intf->interface_id)) 88 return -ENOMEM; 89 if (add_uevent_var(env, "GREYBUS_ID=%08x/%08x", 90 intf->vendor_id, intf->product_id)) 91 return -ENOMEM; 92 if (add_uevent_var(env, "BUNDLE=%u", gbphy_dev->bundle->id)) 93 return -ENOMEM; 94 if (add_uevent_var(env, "BUNDLE_CLASS=%02x", bundle->class)) 95 return -ENOMEM; 96 if (add_uevent_var(env, "GBPHY=%u", gbphy_dev->id)) 97 return -ENOMEM; 98 if (add_uevent_var(env, "PROTOCOL_ID=%02x", cport_desc->protocol_id)) 99 return -ENOMEM; 100 101 return 0; 102 } 103 104 static const struct gbphy_device_id * 105 gbphy_dev_match_id(struct gbphy_device *gbphy_dev, 106 struct gbphy_driver *gbphy_drv) 107 { 108 const struct gbphy_device_id *id = gbphy_drv->id_table; 109 110 if (!id) 111 return NULL; 112 113 for (; id->protocol_id; id++) 114 if (id->protocol_id == gbphy_dev->cport_desc->protocol_id) 115 return id; 116 117 return NULL; 118 } 119 120 static int gbphy_dev_match(struct device *dev, struct device_driver *drv) 121 { 122 struct gbphy_driver *gbphy_drv = to_gbphy_driver(drv); 123 struct gbphy_device *gbphy_dev = to_gbphy_dev(dev); 124 const struct gbphy_device_id *id; 125 126 id = gbphy_dev_match_id(gbphy_dev, gbphy_drv); 127 if (id) 128 return 1; 129 130 return 0; 131 } 132 133 static int gbphy_dev_probe(struct device *dev) 134 { 135 struct gbphy_driver *gbphy_drv = to_gbphy_driver(dev->driver); 136 struct gbphy_device *gbphy_dev = to_gbphy_dev(dev); 137 const struct gbphy_device_id *id; 138 int ret; 139 140 id = gbphy_dev_match_id(gbphy_dev, gbphy_drv); 141 if (!id) 142 return -ENODEV; 143 144 /* for old kernels we need get_sync to resume parent devices */ 145 ret = gb_pm_runtime_get_sync(gbphy_dev->bundle); 146 if (ret < 0) 147 return ret; 148 149 pm_runtime_set_autosuspend_delay(dev, GB_GBPHY_AUTOSUSPEND_MS); 150 pm_runtime_use_autosuspend(dev); 151 pm_runtime_get_noresume(dev); 152 pm_runtime_set_active(dev); 153 pm_runtime_enable(dev); 154 155 /* 156 * Drivers should call put on the gbphy dev before returning 157 * from probe if they support runtime pm. 158 */ 159 ret = gbphy_drv->probe(gbphy_dev, id); 160 if (ret) { 161 pm_runtime_disable(dev); 162 pm_runtime_set_suspended(dev); 163 pm_runtime_put_noidle(dev); 164 pm_runtime_dont_use_autosuspend(dev); 165 } 166 167 gb_pm_runtime_put_autosuspend(gbphy_dev->bundle); 168 169 return ret; 170 } 171 172 static void gbphy_dev_remove(struct device *dev) 173 { 174 struct gbphy_driver *gbphy_drv = to_gbphy_driver(dev->driver); 175 struct gbphy_device *gbphy_dev = to_gbphy_dev(dev); 176 177 gbphy_drv->remove(gbphy_dev); 178 179 pm_runtime_disable(dev); 180 pm_runtime_set_suspended(dev); 181 pm_runtime_put_noidle(dev); 182 pm_runtime_dont_use_autosuspend(dev); 183 } 184 185 static struct bus_type gbphy_bus_type = { 186 .name = "gbphy", 187 .match = gbphy_dev_match, 188 .probe = gbphy_dev_probe, 189 .remove = gbphy_dev_remove, 190 .uevent = gbphy_dev_uevent, 191 }; 192 193 int gb_gbphy_register_driver(struct gbphy_driver *driver, 194 struct module *owner, const char *mod_name) 195 { 196 int retval; 197 198 if (greybus_disabled()) 199 return -ENODEV; 200 201 driver->driver.bus = &gbphy_bus_type; 202 driver->driver.name = driver->name; 203 driver->driver.owner = owner; 204 driver->driver.mod_name = mod_name; 205 206 retval = driver_register(&driver->driver); 207 if (retval) 208 return retval; 209 210 pr_info("registered new driver %s\n", driver->name); 211 return 0; 212 } 213 EXPORT_SYMBOL_GPL(gb_gbphy_register_driver); 214 215 void gb_gbphy_deregister_driver(struct gbphy_driver *driver) 216 { 217 driver_unregister(&driver->driver); 218 } 219 EXPORT_SYMBOL_GPL(gb_gbphy_deregister_driver); 220 221 static struct gbphy_device *gb_gbphy_create_dev(struct gb_bundle *bundle, 222 struct greybus_descriptor_cport *cport_desc) 223 { 224 struct gbphy_device *gbphy_dev; 225 int retval; 226 int id; 227 228 id = ida_simple_get(&gbphy_id, 1, 0, GFP_KERNEL); 229 if (id < 0) 230 return ERR_PTR(id); 231 232 gbphy_dev = kzalloc(sizeof(*gbphy_dev), GFP_KERNEL); 233 if (!gbphy_dev) { 234 ida_simple_remove(&gbphy_id, id); 235 return ERR_PTR(-ENOMEM); 236 } 237 238 gbphy_dev->id = id; 239 gbphy_dev->bundle = bundle; 240 gbphy_dev->cport_desc = cport_desc; 241 gbphy_dev->dev.parent = &bundle->dev; 242 gbphy_dev->dev.bus = &gbphy_bus_type; 243 gbphy_dev->dev.type = &greybus_gbphy_dev_type; 244 gbphy_dev->dev.groups = gbphy_dev_groups; 245 gbphy_dev->dev.dma_mask = bundle->dev.dma_mask; 246 dev_set_name(&gbphy_dev->dev, "gbphy%d", id); 247 248 retval = device_register(&gbphy_dev->dev); 249 if (retval) { 250 put_device(&gbphy_dev->dev); 251 return ERR_PTR(retval); 252 } 253 254 return gbphy_dev; 255 } 256 257 static void gb_gbphy_disconnect(struct gb_bundle *bundle) 258 { 259 struct gbphy_host *gbphy_host = greybus_get_drvdata(bundle); 260 struct gbphy_device *gbphy_dev, *temp; 261 int ret; 262 263 ret = gb_pm_runtime_get_sync(bundle); 264 if (ret < 0) 265 gb_pm_runtime_get_noresume(bundle); 266 267 list_for_each_entry_safe(gbphy_dev, temp, &gbphy_host->devices, list) { 268 list_del(&gbphy_dev->list); 269 device_unregister(&gbphy_dev->dev); 270 } 271 272 kfree(gbphy_host); 273 } 274 275 static int gb_gbphy_probe(struct gb_bundle *bundle, 276 const struct greybus_bundle_id *id) 277 { 278 struct gbphy_host *gbphy_host; 279 struct gbphy_device *gbphy_dev; 280 int i; 281 282 if (bundle->num_cports == 0) 283 return -ENODEV; 284 285 gbphy_host = kzalloc(sizeof(*gbphy_host), GFP_KERNEL); 286 if (!gbphy_host) 287 return -ENOMEM; 288 289 gbphy_host->bundle = bundle; 290 INIT_LIST_HEAD(&gbphy_host->devices); 291 greybus_set_drvdata(bundle, gbphy_host); 292 293 /* 294 * Create a bunch of children devices, one per cport, and bind the 295 * bridged phy drivers to them. 296 */ 297 for (i = 0; i < bundle->num_cports; ++i) { 298 gbphy_dev = gb_gbphy_create_dev(bundle, &bundle->cport_desc[i]); 299 if (IS_ERR(gbphy_dev)) { 300 gb_gbphy_disconnect(bundle); 301 return PTR_ERR(gbphy_dev); 302 } 303 list_add(&gbphy_dev->list, &gbphy_host->devices); 304 } 305 306 gb_pm_runtime_put_autosuspend(bundle); 307 308 return 0; 309 } 310 311 static const struct greybus_bundle_id gb_gbphy_id_table[] = { 312 { GREYBUS_DEVICE_CLASS(GREYBUS_CLASS_BRIDGED_PHY) }, 313 { }, 314 }; 315 MODULE_DEVICE_TABLE(greybus, gb_gbphy_id_table); 316 317 static struct greybus_driver gb_gbphy_driver = { 318 .name = "gbphy", 319 .probe = gb_gbphy_probe, 320 .disconnect = gb_gbphy_disconnect, 321 .id_table = gb_gbphy_id_table, 322 }; 323 324 static int __init gbphy_init(void) 325 { 326 int retval; 327 328 retval = bus_register(&gbphy_bus_type); 329 if (retval) { 330 pr_err("gbphy bus register failed (%d)\n", retval); 331 return retval; 332 } 333 334 retval = greybus_register(&gb_gbphy_driver); 335 if (retval) { 336 pr_err("error registering greybus driver\n"); 337 goto error_gbphy; 338 } 339 340 return 0; 341 342 error_gbphy: 343 bus_unregister(&gbphy_bus_type); 344 ida_destroy(&gbphy_id); 345 return retval; 346 } 347 module_init(gbphy_init); 348 349 static void __exit gbphy_exit(void) 350 { 351 greybus_deregister(&gb_gbphy_driver); 352 bus_unregister(&gbphy_bus_type); 353 ida_destroy(&gbphy_id); 354 } 355 module_exit(gbphy_exit); 356 357 MODULE_LICENSE("GPL v2"); 358