1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * ulpi.c - USB ULPI PHY bus 4 * 5 * Copyright (C) 2015 Intel Corporation 6 * 7 * Author: Heikki Krogerus <heikki.krogerus@linux.intel.com> 8 */ 9 10 #include <linux/ulpi/interface.h> 11 #include <linux/ulpi/driver.h> 12 #include <linux/ulpi/regs.h> 13 #include <linux/module.h> 14 #include <linux/slab.h> 15 #include <linux/acpi.h> 16 #include <linux/debugfs.h> 17 #include <linux/of.h> 18 #include <linux/of_device.h> 19 #include <linux/clk/clk-conf.h> 20 21 /* -------------------------------------------------------------------------- */ 22 23 int ulpi_read(struct ulpi *ulpi, u8 addr) 24 { 25 return ulpi->ops->read(ulpi->dev.parent, addr); 26 } 27 EXPORT_SYMBOL_GPL(ulpi_read); 28 29 int ulpi_write(struct ulpi *ulpi, u8 addr, u8 val) 30 { 31 return ulpi->ops->write(ulpi->dev.parent, addr, val); 32 } 33 EXPORT_SYMBOL_GPL(ulpi_write); 34 35 /* -------------------------------------------------------------------------- */ 36 37 static int ulpi_match(struct device *dev, struct device_driver *driver) 38 { 39 struct ulpi_driver *drv = to_ulpi_driver(driver); 40 struct ulpi *ulpi = to_ulpi_dev(dev); 41 const struct ulpi_device_id *id; 42 43 /* 44 * Some ULPI devices don't have a vendor id 45 * or provide an id_table so rely on OF match. 46 */ 47 if (ulpi->id.vendor == 0 || !drv->id_table) 48 return of_driver_match_device(dev, driver); 49 50 for (id = drv->id_table; id->vendor; id++) 51 if (id->vendor == ulpi->id.vendor && 52 id->product == ulpi->id.product) 53 return 1; 54 55 return 0; 56 } 57 58 static int ulpi_uevent(struct device *dev, struct kobj_uevent_env *env) 59 { 60 struct ulpi *ulpi = to_ulpi_dev(dev); 61 int ret; 62 63 ret = of_device_uevent_modalias(dev, env); 64 if (ret != -ENODEV) 65 return ret; 66 67 if (add_uevent_var(env, "MODALIAS=ulpi:v%04xp%04x", 68 ulpi->id.vendor, ulpi->id.product)) 69 return -ENOMEM; 70 return 0; 71 } 72 73 static int ulpi_probe(struct device *dev) 74 { 75 struct ulpi_driver *drv = to_ulpi_driver(dev->driver); 76 int ret; 77 78 ret = of_clk_set_defaults(dev->of_node, false); 79 if (ret < 0) 80 return ret; 81 82 return drv->probe(to_ulpi_dev(dev)); 83 } 84 85 static void ulpi_remove(struct device *dev) 86 { 87 struct ulpi_driver *drv = to_ulpi_driver(dev->driver); 88 89 if (drv->remove) 90 drv->remove(to_ulpi_dev(dev)); 91 } 92 93 static struct bus_type ulpi_bus = { 94 .name = "ulpi", 95 .match = ulpi_match, 96 .uevent = ulpi_uevent, 97 .probe = ulpi_probe, 98 .remove = ulpi_remove, 99 }; 100 101 /* -------------------------------------------------------------------------- */ 102 103 static ssize_t modalias_show(struct device *dev, struct device_attribute *attr, 104 char *buf) 105 { 106 int len; 107 struct ulpi *ulpi = to_ulpi_dev(dev); 108 109 len = of_device_modalias(dev, buf, PAGE_SIZE); 110 if (len != -ENODEV) 111 return len; 112 113 return sprintf(buf, "ulpi:v%04xp%04x\n", 114 ulpi->id.vendor, ulpi->id.product); 115 } 116 static DEVICE_ATTR_RO(modalias); 117 118 static struct attribute *ulpi_dev_attrs[] = { 119 &dev_attr_modalias.attr, 120 NULL 121 }; 122 123 static const struct attribute_group ulpi_dev_attr_group = { 124 .attrs = ulpi_dev_attrs, 125 }; 126 127 static const struct attribute_group *ulpi_dev_attr_groups[] = { 128 &ulpi_dev_attr_group, 129 NULL 130 }; 131 132 static void ulpi_dev_release(struct device *dev) 133 { 134 of_node_put(dev->of_node); 135 kfree(to_ulpi_dev(dev)); 136 } 137 138 static const struct device_type ulpi_dev_type = { 139 .name = "ulpi_device", 140 .groups = ulpi_dev_attr_groups, 141 .release = ulpi_dev_release, 142 }; 143 144 /* -------------------------------------------------------------------------- */ 145 146 /** 147 * __ulpi_register_driver - register a driver with the ULPI bus 148 * @drv: driver being registered 149 * @module: ends up being THIS_MODULE 150 * 151 * Registers a driver with the ULPI bus. 152 */ 153 int __ulpi_register_driver(struct ulpi_driver *drv, struct module *module) 154 { 155 if (!drv->probe) 156 return -EINVAL; 157 158 drv->driver.owner = module; 159 drv->driver.bus = &ulpi_bus; 160 161 return driver_register(&drv->driver); 162 } 163 EXPORT_SYMBOL_GPL(__ulpi_register_driver); 164 165 /** 166 * ulpi_unregister_driver - unregister a driver with the ULPI bus 167 * @drv: driver to unregister 168 * 169 * Unregisters a driver with the ULPI bus. 170 */ 171 void ulpi_unregister_driver(struct ulpi_driver *drv) 172 { 173 driver_unregister(&drv->driver); 174 } 175 EXPORT_SYMBOL_GPL(ulpi_unregister_driver); 176 177 /* -------------------------------------------------------------------------- */ 178 179 static int ulpi_of_register(struct ulpi *ulpi) 180 { 181 struct device_node *np = NULL, *child; 182 struct device *parent; 183 184 /* Find a ulpi bus underneath the parent or the grandparent */ 185 parent = ulpi->dev.parent; 186 if (parent->of_node) 187 np = of_get_child_by_name(parent->of_node, "ulpi"); 188 else if (parent->parent && parent->parent->of_node) 189 np = of_get_child_by_name(parent->parent->of_node, "ulpi"); 190 if (!np) 191 return 0; 192 193 child = of_get_next_available_child(np, NULL); 194 of_node_put(np); 195 if (!child) 196 return -EINVAL; 197 198 ulpi->dev.of_node = child; 199 200 return 0; 201 } 202 203 static int ulpi_read_id(struct ulpi *ulpi) 204 { 205 int ret; 206 207 /* Test the interface */ 208 ret = ulpi_write(ulpi, ULPI_SCRATCH, 0xaa); 209 if (ret < 0) 210 goto err; 211 212 ret = ulpi_read(ulpi, ULPI_SCRATCH); 213 if (ret < 0) 214 return ret; 215 216 if (ret != 0xaa) 217 goto err; 218 219 ulpi->id.vendor = ulpi_read(ulpi, ULPI_VENDOR_ID_LOW); 220 ulpi->id.vendor |= ulpi_read(ulpi, ULPI_VENDOR_ID_HIGH) << 8; 221 222 ulpi->id.product = ulpi_read(ulpi, ULPI_PRODUCT_ID_LOW); 223 ulpi->id.product |= ulpi_read(ulpi, ULPI_PRODUCT_ID_HIGH) << 8; 224 225 /* Some ULPI devices don't have a vendor id so rely on OF match */ 226 if (ulpi->id.vendor == 0) 227 goto err; 228 229 request_module("ulpi:v%04xp%04x", ulpi->id.vendor, ulpi->id.product); 230 return 0; 231 err: 232 of_device_request_module(&ulpi->dev); 233 return 0; 234 } 235 236 static int ulpi_regs_show(struct seq_file *seq, void *data) 237 { 238 struct ulpi *ulpi = seq->private; 239 240 #define ulpi_print(name, reg) do { \ 241 int ret = ulpi_read(ulpi, reg); \ 242 if (ret < 0) \ 243 return ret; \ 244 seq_printf(seq, name " %.02x\n", ret); \ 245 } while (0) 246 247 ulpi_print("Vendor ID Low ", ULPI_VENDOR_ID_LOW); 248 ulpi_print("Vendor ID High ", ULPI_VENDOR_ID_HIGH); 249 ulpi_print("Product ID Low ", ULPI_PRODUCT_ID_LOW); 250 ulpi_print("Product ID High ", ULPI_PRODUCT_ID_HIGH); 251 ulpi_print("Function Control ", ULPI_FUNC_CTRL); 252 ulpi_print("Interface Control ", ULPI_IFC_CTRL); 253 ulpi_print("OTG Control ", ULPI_OTG_CTRL); 254 ulpi_print("USB Interrupt Enable Rising ", ULPI_USB_INT_EN_RISE); 255 ulpi_print("USB Interrupt Enable Falling", ULPI_USB_INT_EN_FALL); 256 ulpi_print("USB Interrupt Status ", ULPI_USB_INT_STS); 257 ulpi_print("USB Interrupt Latch ", ULPI_USB_INT_LATCH); 258 ulpi_print("Debug ", ULPI_DEBUG); 259 ulpi_print("Scratch Register ", ULPI_SCRATCH); 260 ulpi_print("Carkit Control ", ULPI_CARKIT_CTRL); 261 ulpi_print("Carkit Interrupt Delay ", ULPI_CARKIT_INT_DELAY); 262 ulpi_print("Carkit Interrupt Enable ", ULPI_CARKIT_INT_EN); 263 ulpi_print("Carkit Interrupt Status ", ULPI_CARKIT_INT_STS); 264 ulpi_print("Carkit Interrupt Latch ", ULPI_CARKIT_INT_LATCH); 265 ulpi_print("Carkit Pulse Control ", ULPI_CARKIT_PLS_CTRL); 266 ulpi_print("Transmit Positive Width ", ULPI_TX_POS_WIDTH); 267 ulpi_print("Transmit Negative Width ", ULPI_TX_NEG_WIDTH); 268 ulpi_print("Receive Polarity Recovery ", ULPI_POLARITY_RECOVERY); 269 270 return 0; 271 } 272 DEFINE_SHOW_ATTRIBUTE(ulpi_regs); 273 274 #define ULPI_ROOT debugfs_lookup(KBUILD_MODNAME, NULL) 275 276 static int ulpi_register(struct device *dev, struct ulpi *ulpi) 277 { 278 int ret; 279 struct dentry *root; 280 281 ulpi->dev.parent = dev; /* needed early for ops */ 282 ulpi->dev.bus = &ulpi_bus; 283 ulpi->dev.type = &ulpi_dev_type; 284 dev_set_name(&ulpi->dev, "%s.ulpi", dev_name(dev)); 285 286 ACPI_COMPANION_SET(&ulpi->dev, ACPI_COMPANION(dev)); 287 288 ret = ulpi_of_register(ulpi); 289 if (ret) 290 return ret; 291 292 ret = ulpi_read_id(ulpi); 293 if (ret) { 294 of_node_put(ulpi->dev.of_node); 295 return ret; 296 } 297 298 ret = device_register(&ulpi->dev); 299 if (ret) { 300 put_device(&ulpi->dev); 301 return ret; 302 } 303 304 root = debugfs_create_dir(dev_name(dev), ULPI_ROOT); 305 debugfs_create_file("regs", 0444, root, ulpi, &ulpi_regs_fops); 306 307 dev_dbg(&ulpi->dev, "registered ULPI PHY: vendor %04x, product %04x\n", 308 ulpi->id.vendor, ulpi->id.product); 309 310 return 0; 311 } 312 313 /** 314 * ulpi_register_interface - instantiate new ULPI device 315 * @dev: USB controller's device interface 316 * @ops: ULPI register access 317 * 318 * Allocates and registers a ULPI device and an interface for it. Called from 319 * the USB controller that provides the ULPI interface. 320 */ 321 struct ulpi *ulpi_register_interface(struct device *dev, 322 const struct ulpi_ops *ops) 323 { 324 struct ulpi *ulpi; 325 int ret; 326 327 ulpi = kzalloc(sizeof(*ulpi), GFP_KERNEL); 328 if (!ulpi) 329 return ERR_PTR(-ENOMEM); 330 331 ulpi->ops = ops; 332 333 ret = ulpi_register(dev, ulpi); 334 if (ret) { 335 kfree(ulpi); 336 return ERR_PTR(ret); 337 } 338 339 return ulpi; 340 } 341 EXPORT_SYMBOL_GPL(ulpi_register_interface); 342 343 /** 344 * ulpi_unregister_interface - unregister ULPI interface 345 * @ulpi: struct ulpi_interface 346 * 347 * Unregisters a ULPI device and it's interface that was created with 348 * ulpi_create_interface(). 349 */ 350 void ulpi_unregister_interface(struct ulpi *ulpi) 351 { 352 debugfs_remove_recursive(debugfs_lookup(dev_name(&ulpi->dev), 353 ULPI_ROOT)); 354 device_unregister(&ulpi->dev); 355 } 356 EXPORT_SYMBOL_GPL(ulpi_unregister_interface); 357 358 /* -------------------------------------------------------------------------- */ 359 360 static int __init ulpi_init(void) 361 { 362 int ret; 363 struct dentry *root; 364 365 root = debugfs_create_dir(KBUILD_MODNAME, NULL); 366 ret = bus_register(&ulpi_bus); 367 if (ret) 368 debugfs_remove(root); 369 return ret; 370 } 371 subsys_initcall(ulpi_init); 372 373 static void __exit ulpi_exit(void) 374 { 375 bus_unregister(&ulpi_bus); 376 debugfs_remove_recursive(ULPI_ROOT); 377 } 378 module_exit(ulpi_exit); 379 380 MODULE_AUTHOR("Intel Corporation"); 381 MODULE_LICENSE("GPL v2"); 382 MODULE_DESCRIPTION("USB ULPI PHY bus"); 383