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->ops, 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->ops, 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 /* Test the interface */ 161 ret = ulpi_write(ulpi, ULPI_SCRATCH, 0xaa); 162 if (ret < 0) 163 return ret; 164 165 ret = ulpi_read(ulpi, ULPI_SCRATCH); 166 if (ret < 0) 167 return ret; 168 169 if (ret != 0xaa) 170 return -ENODEV; 171 172 ulpi->id.vendor = ulpi_read(ulpi, ULPI_VENDOR_ID_LOW); 173 ulpi->id.vendor |= ulpi_read(ulpi, ULPI_VENDOR_ID_HIGH) << 8; 174 175 ulpi->id.product = ulpi_read(ulpi, ULPI_PRODUCT_ID_LOW); 176 ulpi->id.product |= ulpi_read(ulpi, ULPI_PRODUCT_ID_HIGH) << 8; 177 178 ulpi->dev.parent = dev; 179 ulpi->dev.bus = &ulpi_bus; 180 ulpi->dev.type = &ulpi_dev_type; 181 dev_set_name(&ulpi->dev, "%s.ulpi", dev_name(dev)); 182 183 ACPI_COMPANION_SET(&ulpi->dev, ACPI_COMPANION(dev)); 184 185 request_module("ulpi:v%04xp%04x", ulpi->id.vendor, ulpi->id.product); 186 187 ret = device_register(&ulpi->dev); 188 if (ret) 189 return ret; 190 191 dev_dbg(&ulpi->dev, "registered ULPI PHY: vendor %04x, product %04x\n", 192 ulpi->id.vendor, ulpi->id.product); 193 194 return 0; 195 } 196 197 /** 198 * ulpi_register_interface - instantiate new ULPI device 199 * @dev: USB controller's device interface 200 * @ops: ULPI register access 201 * 202 * Allocates and registers a ULPI device and an interface for it. Called from 203 * the USB controller that provides the ULPI interface. 204 */ 205 struct ulpi *ulpi_register_interface(struct device *dev, struct ulpi_ops *ops) 206 { 207 struct ulpi *ulpi; 208 int ret; 209 210 ulpi = kzalloc(sizeof(*ulpi), GFP_KERNEL); 211 if (!ulpi) 212 return ERR_PTR(-ENOMEM); 213 214 ulpi->ops = ops; 215 ops->dev = dev; 216 217 ret = ulpi_register(dev, ulpi); 218 if (ret) { 219 kfree(ulpi); 220 return ERR_PTR(ret); 221 } 222 223 return ulpi; 224 } 225 EXPORT_SYMBOL_GPL(ulpi_register_interface); 226 227 /** 228 * ulpi_unregister_interface - unregister ULPI interface 229 * @intrf: struct ulpi_interface 230 * 231 * Unregisters a ULPI device and it's interface that was created with 232 * ulpi_create_interface(). 233 */ 234 void ulpi_unregister_interface(struct ulpi *ulpi) 235 { 236 device_unregister(&ulpi->dev); 237 } 238 EXPORT_SYMBOL_GPL(ulpi_unregister_interface); 239 240 /* -------------------------------------------------------------------------- */ 241 242 static int __init ulpi_init(void) 243 { 244 return bus_register(&ulpi_bus); 245 } 246 subsys_initcall(ulpi_init); 247 248 static void __exit ulpi_exit(void) 249 { 250 bus_unregister(&ulpi_bus); 251 } 252 module_exit(ulpi_exit); 253 254 MODULE_AUTHOR("Intel Corporation"); 255 MODULE_LICENSE("GPL v2"); 256 MODULE_DESCRIPTION("USB ULPI PHY bus"); 257