1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Copyright (c) 2011-2016 Synaptics Incorporated 4 * Copyright (c) 2011 Unixphere 5 */ 6 7 #include <linux/kernel.h> 8 #include <linux/device.h> 9 #include <linux/irq.h> 10 #include <linux/irqdomain.h> 11 #include <linux/list.h> 12 #include <linux/pm.h> 13 #include <linux/rmi.h> 14 #include <linux/slab.h> 15 #include <linux/types.h> 16 #include <linux/of.h> 17 #include "rmi_bus.h" 18 #include "rmi_driver.h" 19 20 static int debug_flags; 21 module_param(debug_flags, int, 0644); 22 MODULE_PARM_DESC(debug_flags, "control debugging information"); 23 24 void rmi_dbg(int flags, struct device *dev, const char *fmt, ...) 25 { 26 struct va_format vaf; 27 va_list args; 28 29 if (flags & debug_flags) { 30 va_start(args, fmt); 31 32 vaf.fmt = fmt; 33 vaf.va = &args; 34 35 dev_printk(KERN_DEBUG, dev, "%pV", &vaf); 36 37 va_end(args); 38 } 39 } 40 EXPORT_SYMBOL_GPL(rmi_dbg); 41 42 /* 43 * RMI Physical devices 44 * 45 * Physical RMI device consists of several functions serving particular 46 * purpose. For example F11 is a 2D touch sensor while F01 is a generic 47 * function present in every RMI device. 48 */ 49 50 static void rmi_release_device(struct device *dev) 51 { 52 struct rmi_device *rmi_dev = to_rmi_device(dev); 53 54 kfree(rmi_dev); 55 } 56 57 static const struct device_type rmi_device_type = { 58 .name = "rmi4_sensor", 59 .release = rmi_release_device, 60 }; 61 62 bool rmi_is_physical_device(struct device *dev) 63 { 64 return dev->type == &rmi_device_type; 65 } 66 67 /** 68 * rmi_register_transport_device - register a transport device connection 69 * on the RMI bus. Transport drivers provide communication from the devices 70 * on a bus (such as SPI, I2C, and so on) to the RMI4 sensor. 71 * 72 * @xport: the transport device to register 73 */ 74 int rmi_register_transport_device(struct rmi_transport_dev *xport) 75 { 76 static atomic_t transport_device_count = ATOMIC_INIT(0); 77 struct rmi_device *rmi_dev; 78 int error; 79 80 rmi_dev = kzalloc(sizeof(struct rmi_device), GFP_KERNEL); 81 if (!rmi_dev) 82 return -ENOMEM; 83 84 device_initialize(&rmi_dev->dev); 85 86 rmi_dev->xport = xport; 87 rmi_dev->number = atomic_inc_return(&transport_device_count) - 1; 88 89 dev_set_name(&rmi_dev->dev, "rmi4-%02d", rmi_dev->number); 90 91 rmi_dev->dev.bus = &rmi_bus_type; 92 rmi_dev->dev.type = &rmi_device_type; 93 94 xport->rmi_dev = rmi_dev; 95 96 error = device_add(&rmi_dev->dev); 97 if (error) 98 goto err_put_device; 99 100 rmi_dbg(RMI_DEBUG_CORE, xport->dev, 101 "%s: Registered %s as %s.\n", __func__, 102 dev_name(rmi_dev->xport->dev), dev_name(&rmi_dev->dev)); 103 104 return 0; 105 106 err_put_device: 107 put_device(&rmi_dev->dev); 108 return error; 109 } 110 EXPORT_SYMBOL_GPL(rmi_register_transport_device); 111 112 /** 113 * rmi_unregister_transport_device - unregister a transport device connection 114 * @xport: the transport driver to unregister 115 * 116 */ 117 void rmi_unregister_transport_device(struct rmi_transport_dev *xport) 118 { 119 struct rmi_device *rmi_dev = xport->rmi_dev; 120 121 device_del(&rmi_dev->dev); 122 put_device(&rmi_dev->dev); 123 } 124 EXPORT_SYMBOL(rmi_unregister_transport_device); 125 126 127 /* Function specific stuff */ 128 129 static void rmi_release_function(struct device *dev) 130 { 131 struct rmi_function *fn = to_rmi_function(dev); 132 133 kfree(fn); 134 } 135 136 static const struct device_type rmi_function_type = { 137 .name = "rmi4_function", 138 .release = rmi_release_function, 139 }; 140 141 bool rmi_is_function_device(struct device *dev) 142 { 143 return dev->type == &rmi_function_type; 144 } 145 146 static int rmi_function_match(struct device *dev, struct device_driver *drv) 147 { 148 struct rmi_function_handler *handler = to_rmi_function_handler(drv); 149 struct rmi_function *fn = to_rmi_function(dev); 150 151 return fn->fd.function_number == handler->func; 152 } 153 154 #ifdef CONFIG_OF 155 static void rmi_function_of_probe(struct rmi_function *fn) 156 { 157 char of_name[9]; 158 struct device_node *node = fn->rmi_dev->xport->dev->of_node; 159 160 snprintf(of_name, sizeof(of_name), "rmi4-f%02x", 161 fn->fd.function_number); 162 fn->dev.of_node = of_get_child_by_name(node, of_name); 163 } 164 #else 165 static inline void rmi_function_of_probe(struct rmi_function *fn) 166 {} 167 #endif 168 169 static struct irq_chip rmi_irq_chip = { 170 .name = "rmi4", 171 }; 172 173 static int rmi_create_function_irq(struct rmi_function *fn, 174 struct rmi_function_handler *handler) 175 { 176 struct rmi_driver_data *drvdata = dev_get_drvdata(&fn->rmi_dev->dev); 177 int i, error; 178 179 for (i = 0; i < fn->num_of_irqs; i++) { 180 set_bit(fn->irq_pos + i, fn->irq_mask); 181 182 fn->irq[i] = irq_create_mapping(drvdata->irqdomain, 183 fn->irq_pos + i); 184 185 irq_set_chip_data(fn->irq[i], fn); 186 irq_set_chip_and_handler(fn->irq[i], &rmi_irq_chip, 187 handle_simple_irq); 188 irq_set_nested_thread(fn->irq[i], 1); 189 190 error = devm_request_threaded_irq(&fn->dev, fn->irq[i], NULL, 191 handler->attention, IRQF_ONESHOT, 192 dev_name(&fn->dev), fn); 193 if (error) { 194 dev_err(&fn->dev, "Error %d registering IRQ\n", error); 195 return error; 196 } 197 } 198 199 return 0; 200 } 201 202 static int rmi_function_probe(struct device *dev) 203 { 204 struct rmi_function *fn = to_rmi_function(dev); 205 struct rmi_function_handler *handler = 206 to_rmi_function_handler(dev->driver); 207 int error; 208 209 rmi_function_of_probe(fn); 210 211 if (handler->probe) { 212 error = handler->probe(fn); 213 if (error) 214 return error; 215 } 216 217 if (fn->num_of_irqs && handler->attention) { 218 error = rmi_create_function_irq(fn, handler); 219 if (error) 220 return error; 221 } 222 223 return 0; 224 } 225 226 static int rmi_function_remove(struct device *dev) 227 { 228 struct rmi_function *fn = to_rmi_function(dev); 229 struct rmi_function_handler *handler = 230 to_rmi_function_handler(dev->driver); 231 232 if (handler->remove) 233 handler->remove(fn); 234 235 return 0; 236 } 237 238 int rmi_register_function(struct rmi_function *fn) 239 { 240 struct rmi_device *rmi_dev = fn->rmi_dev; 241 int error; 242 243 device_initialize(&fn->dev); 244 245 dev_set_name(&fn->dev, "%s.fn%02x", 246 dev_name(&rmi_dev->dev), fn->fd.function_number); 247 248 fn->dev.parent = &rmi_dev->dev; 249 fn->dev.type = &rmi_function_type; 250 fn->dev.bus = &rmi_bus_type; 251 252 error = device_add(&fn->dev); 253 if (error) { 254 dev_err(&rmi_dev->dev, 255 "Failed device_register function device %s\n", 256 dev_name(&fn->dev)); 257 goto err_put_device; 258 } 259 260 rmi_dbg(RMI_DEBUG_CORE, &rmi_dev->dev, "Registered F%02X.\n", 261 fn->fd.function_number); 262 263 return 0; 264 265 err_put_device: 266 put_device(&fn->dev); 267 return error; 268 } 269 270 void rmi_unregister_function(struct rmi_function *fn) 271 { 272 int i; 273 274 rmi_dbg(RMI_DEBUG_CORE, &fn->dev, "Unregistering F%02X.\n", 275 fn->fd.function_number); 276 277 device_del(&fn->dev); 278 of_node_put(fn->dev.of_node); 279 put_device(&fn->dev); 280 281 for (i = 0; i < fn->num_of_irqs; i++) 282 irq_dispose_mapping(fn->irq[i]); 283 284 } 285 286 /** 287 * rmi_register_function_handler - register a handler for an RMI function 288 * @handler: RMI handler that should be registered. 289 * @module: pointer to module that implements the handler 290 * @mod_name: name of the module implementing the handler 291 * 292 * This function performs additional setup of RMI function handler and 293 * registers it with the RMI core so that it can be bound to 294 * RMI function devices. 295 */ 296 int __rmi_register_function_handler(struct rmi_function_handler *handler, 297 struct module *owner, 298 const char *mod_name) 299 { 300 struct device_driver *driver = &handler->driver; 301 int error; 302 303 driver->bus = &rmi_bus_type; 304 driver->owner = owner; 305 driver->mod_name = mod_name; 306 driver->probe = rmi_function_probe; 307 driver->remove = rmi_function_remove; 308 309 error = driver_register(driver); 310 if (error) { 311 pr_err("driver_register() failed for %s, error: %d\n", 312 driver->name, error); 313 return error; 314 } 315 316 return 0; 317 } 318 EXPORT_SYMBOL_GPL(__rmi_register_function_handler); 319 320 /** 321 * rmi_unregister_function_handler - unregister given RMI function handler 322 * @handler: RMI handler that should be unregistered. 323 * 324 * This function unregisters given function handler from RMI core which 325 * causes it to be unbound from the function devices. 326 */ 327 void rmi_unregister_function_handler(struct rmi_function_handler *handler) 328 { 329 driver_unregister(&handler->driver); 330 } 331 EXPORT_SYMBOL_GPL(rmi_unregister_function_handler); 332 333 /* Bus specific stuff */ 334 335 static int rmi_bus_match(struct device *dev, struct device_driver *drv) 336 { 337 bool physical = rmi_is_physical_device(dev); 338 339 /* First see if types are not compatible */ 340 if (physical != rmi_is_physical_driver(drv)) 341 return 0; 342 343 return physical || rmi_function_match(dev, drv); 344 } 345 346 struct bus_type rmi_bus_type = { 347 .match = rmi_bus_match, 348 .name = "rmi4", 349 }; 350 351 static struct rmi_function_handler *fn_handlers[] = { 352 &rmi_f01_handler, 353 #ifdef CONFIG_RMI4_F03 354 &rmi_f03_handler, 355 #endif 356 #ifdef CONFIG_RMI4_F11 357 &rmi_f11_handler, 358 #endif 359 #ifdef CONFIG_RMI4_F12 360 &rmi_f12_handler, 361 #endif 362 #ifdef CONFIG_RMI4_F30 363 &rmi_f30_handler, 364 #endif 365 #ifdef CONFIG_RMI4_F34 366 &rmi_f34_handler, 367 #endif 368 #ifdef CONFIG_RMI4_F54 369 &rmi_f54_handler, 370 #endif 371 #ifdef CONFIG_RMI4_F55 372 &rmi_f55_handler, 373 #endif 374 }; 375 376 static void __rmi_unregister_function_handlers(int start_idx) 377 { 378 int i; 379 380 for (i = start_idx; i >= 0; i--) 381 rmi_unregister_function_handler(fn_handlers[i]); 382 } 383 384 static void rmi_unregister_function_handlers(void) 385 { 386 __rmi_unregister_function_handlers(ARRAY_SIZE(fn_handlers) - 1); 387 } 388 389 static int rmi_register_function_handlers(void) 390 { 391 int ret; 392 int i; 393 394 for (i = 0; i < ARRAY_SIZE(fn_handlers); i++) { 395 ret = rmi_register_function_handler(fn_handlers[i]); 396 if (ret) { 397 pr_err("%s: error registering the RMI F%02x handler: %d\n", 398 __func__, fn_handlers[i]->func, ret); 399 goto err_unregister_function_handlers; 400 } 401 } 402 403 return 0; 404 405 err_unregister_function_handlers: 406 __rmi_unregister_function_handlers(i - 1); 407 return ret; 408 } 409 410 int rmi_of_property_read_u32(struct device *dev, u32 *result, 411 const char *prop, bool optional) 412 { 413 int retval; 414 u32 val = 0; 415 416 retval = of_property_read_u32(dev->of_node, prop, &val); 417 if (retval && (!optional && retval == -EINVAL)) { 418 dev_err(dev, "Failed to get %s value: %d\n", 419 prop, retval); 420 return retval; 421 } 422 *result = val; 423 424 return 0; 425 } 426 EXPORT_SYMBOL_GPL(rmi_of_property_read_u32); 427 428 static int __init rmi_bus_init(void) 429 { 430 int error; 431 432 error = bus_register(&rmi_bus_type); 433 if (error) { 434 pr_err("%s: error registering the RMI bus: %d\n", 435 __func__, error); 436 return error; 437 } 438 439 error = rmi_register_function_handlers(); 440 if (error) 441 goto err_unregister_bus; 442 443 error = rmi_register_physical_driver(); 444 if (error) { 445 pr_err("%s: error registering the RMI physical driver: %d\n", 446 __func__, error); 447 goto err_unregister_bus; 448 } 449 450 return 0; 451 452 err_unregister_bus: 453 bus_unregister(&rmi_bus_type); 454 return error; 455 } 456 module_init(rmi_bus_init); 457 458 static void __exit rmi_bus_exit(void) 459 { 460 /* 461 * We should only ever get here if all drivers are unloaded, so 462 * all we have to do at this point is unregister ourselves. 463 */ 464 465 rmi_unregister_physical_driver(); 466 rmi_unregister_function_handlers(); 467 bus_unregister(&rmi_bus_type); 468 } 469 module_exit(rmi_bus_exit); 470 471 MODULE_AUTHOR("Christopher Heiny <cheiny@synaptics.com"); 472 MODULE_AUTHOR("Andrew Duggan <aduggan@synaptics.com"); 473 MODULE_DESCRIPTION("RMI bus"); 474 MODULE_LICENSE("GPL"); 475