1 /** 2 * ulpi.c - USB ULPI PHY bus 3 * 4 * Copyright (C) 2015 Intel Corporation 5 * 6 * Author: Heikki Krogerus <heikki.krogerus@linux.intel.com> 7 * 8 * This program is free software; you can redistribute it and/or modify 9 * it under the terms of the GNU General Public License version 2 as 10 * published by the Free Software Foundation. 11 */ 12 13 #include <linux/ulpi/interface.h> 14 #include <linux/ulpi/driver.h> 15 #include <linux/ulpi/regs.h> 16 #include <linux/module.h> 17 #include <linux/slab.h> 18 #include <linux/acpi.h> 19 20 /* -------------------------------------------------------------------------- */ 21 22 int ulpi_read(struct ulpi *ulpi, u8 addr) 23 { 24 return ulpi->ops->read(ulpi->dev.parent, addr); 25 } 26 EXPORT_SYMBOL_GPL(ulpi_read); 27 28 int ulpi_write(struct ulpi *ulpi, u8 addr, u8 val) 29 { 30 return ulpi->ops->write(ulpi->dev.parent, addr, val); 31 } 32 EXPORT_SYMBOL_GPL(ulpi_write); 33 34 /* -------------------------------------------------------------------------- */ 35 36 static int ulpi_match(struct device *dev, struct device_driver *driver) 37 { 38 struct ulpi_driver *drv = to_ulpi_driver(driver); 39 struct ulpi *ulpi = to_ulpi_dev(dev); 40 const struct ulpi_device_id *id; 41 42 for (id = drv->id_table; id->vendor; id++) 43 if (id->vendor == ulpi->id.vendor && 44 id->product == ulpi->id.product) 45 return 1; 46 47 return 0; 48 } 49 50 static int ulpi_uevent(struct device *dev, struct kobj_uevent_env *env) 51 { 52 struct ulpi *ulpi = to_ulpi_dev(dev); 53 54 if (add_uevent_var(env, "MODALIAS=ulpi:v%04xp%04x", 55 ulpi->id.vendor, ulpi->id.product)) 56 return -ENOMEM; 57 return 0; 58 } 59 60 static int ulpi_probe(struct device *dev) 61 { 62 struct ulpi_driver *drv = to_ulpi_driver(dev->driver); 63 64 return drv->probe(to_ulpi_dev(dev)); 65 } 66 67 static int ulpi_remove(struct device *dev) 68 { 69 struct ulpi_driver *drv = to_ulpi_driver(dev->driver); 70 71 if (drv->remove) 72 drv->remove(to_ulpi_dev(dev)); 73 74 return 0; 75 } 76 77 static struct bus_type ulpi_bus = { 78 .name = "ulpi", 79 .match = ulpi_match, 80 .uevent = ulpi_uevent, 81 .probe = ulpi_probe, 82 .remove = ulpi_remove, 83 }; 84 85 /* -------------------------------------------------------------------------- */ 86 87 static ssize_t modalias_show(struct device *dev, struct device_attribute *attr, 88 char *buf) 89 { 90 struct ulpi *ulpi = to_ulpi_dev(dev); 91 92 return sprintf(buf, "ulpi:v%04xp%04x\n", 93 ulpi->id.vendor, ulpi->id.product); 94 } 95 static DEVICE_ATTR_RO(modalias); 96 97 static struct attribute *ulpi_dev_attrs[] = { 98 &dev_attr_modalias.attr, 99 NULL 100 }; 101 102 static struct attribute_group ulpi_dev_attr_group = { 103 .attrs = ulpi_dev_attrs, 104 }; 105 106 static const struct attribute_group *ulpi_dev_attr_groups[] = { 107 &ulpi_dev_attr_group, 108 NULL 109 }; 110 111 static void ulpi_dev_release(struct device *dev) 112 { 113 kfree(to_ulpi_dev(dev)); 114 } 115 116 static struct device_type ulpi_dev_type = { 117 .name = "ulpi_device", 118 .groups = ulpi_dev_attr_groups, 119 .release = ulpi_dev_release, 120 }; 121 122 /* -------------------------------------------------------------------------- */ 123 124 /** 125 * ulpi_register_driver - register a driver with the ULPI bus 126 * @drv: driver being registered 127 * 128 * Registers a driver with the ULPI bus. 129 */ 130 int __ulpi_register_driver(struct ulpi_driver *drv, struct module *module) 131 { 132 if (!drv->probe) 133 return -EINVAL; 134 135 drv->driver.owner = module; 136 drv->driver.bus = &ulpi_bus; 137 138 return driver_register(&drv->driver); 139 } 140 EXPORT_SYMBOL_GPL(__ulpi_register_driver); 141 142 /** 143 * ulpi_unregister_driver - unregister a driver with the ULPI bus 144 * @drv: driver to unregister 145 * 146 * Unregisters a driver with the ULPI bus. 147 */ 148 void ulpi_unregister_driver(struct ulpi_driver *drv) 149 { 150 driver_unregister(&drv->driver); 151 } 152 EXPORT_SYMBOL_GPL(ulpi_unregister_driver); 153 154 /* -------------------------------------------------------------------------- */ 155 156 static int ulpi_register(struct device *dev, struct ulpi *ulpi) 157 { 158 int ret; 159 160 ulpi->dev.parent = dev; /* needed early for ops */ 161 162 /* Test the interface */ 163 ret = ulpi_write(ulpi, ULPI_SCRATCH, 0xaa); 164 if (ret < 0) 165 return ret; 166 167 ret = ulpi_read(ulpi, ULPI_SCRATCH); 168 if (ret < 0) 169 return ret; 170 171 if (ret != 0xaa) 172 return -ENODEV; 173 174 ulpi->id.vendor = ulpi_read(ulpi, ULPI_VENDOR_ID_LOW); 175 ulpi->id.vendor |= ulpi_read(ulpi, ULPI_VENDOR_ID_HIGH) << 8; 176 177 ulpi->id.product = ulpi_read(ulpi, ULPI_PRODUCT_ID_LOW); 178 ulpi->id.product |= ulpi_read(ulpi, ULPI_PRODUCT_ID_HIGH) << 8; 179 180 ulpi->dev.bus = &ulpi_bus; 181 ulpi->dev.type = &ulpi_dev_type; 182 dev_set_name(&ulpi->dev, "%s.ulpi", dev_name(dev)); 183 184 ACPI_COMPANION_SET(&ulpi->dev, ACPI_COMPANION(dev)); 185 186 request_module("ulpi:v%04xp%04x", ulpi->id.vendor, ulpi->id.product); 187 188 ret = device_register(&ulpi->dev); 189 if (ret) 190 return ret; 191 192 dev_dbg(&ulpi->dev, "registered ULPI PHY: vendor %04x, product %04x\n", 193 ulpi->id.vendor, ulpi->id.product); 194 195 return 0; 196 } 197 198 /** 199 * ulpi_register_interface - instantiate new ULPI device 200 * @dev: USB controller's device interface 201 * @ops: ULPI register access 202 * 203 * Allocates and registers a ULPI device and an interface for it. Called from 204 * the USB controller that provides the ULPI interface. 205 */ 206 struct ulpi *ulpi_register_interface(struct device *dev, 207 const struct ulpi_ops *ops) 208 { 209 struct ulpi *ulpi; 210 int ret; 211 212 ulpi = kzalloc(sizeof(*ulpi), GFP_KERNEL); 213 if (!ulpi) 214 return ERR_PTR(-ENOMEM); 215 216 ulpi->ops = ops; 217 218 ret = ulpi_register(dev, ulpi); 219 if (ret) { 220 kfree(ulpi); 221 return ERR_PTR(ret); 222 } 223 224 return ulpi; 225 } 226 EXPORT_SYMBOL_GPL(ulpi_register_interface); 227 228 /** 229 * ulpi_unregister_interface - unregister ULPI interface 230 * @intrf: struct ulpi_interface 231 * 232 * Unregisters a ULPI device and it's interface that was created with 233 * ulpi_create_interface(). 234 */ 235 void ulpi_unregister_interface(struct ulpi *ulpi) 236 { 237 device_unregister(&ulpi->dev); 238 } 239 EXPORT_SYMBOL_GPL(ulpi_unregister_interface); 240 241 /* -------------------------------------------------------------------------- */ 242 243 static int __init ulpi_init(void) 244 { 245 return bus_register(&ulpi_bus); 246 } 247 subsys_initcall(ulpi_init); 248 249 static void __exit ulpi_exit(void) 250 { 251 bus_unregister(&ulpi_bus); 252 } 253 module_exit(ulpi_exit); 254 255 MODULE_AUTHOR("Intel Corporation"); 256 MODULE_LICENSE("GPL v2"); 257 MODULE_DESCRIPTION("USB ULPI PHY bus"); 258