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) 131 { 132 if (!drv->probe) 133 return -EINVAL; 134 135 drv->driver.bus = &ulpi_bus; 136 137 return driver_register(&drv->driver); 138 } 139 EXPORT_SYMBOL_GPL(ulpi_register_driver); 140 141 /** 142 * ulpi_unregister_driver - unregister a driver with the ULPI bus 143 * @drv: driver to unregister 144 * 145 * Unregisters a driver with the ULPI bus. 146 */ 147 void ulpi_unregister_driver(struct ulpi_driver *drv) 148 { 149 driver_unregister(&drv->driver); 150 } 151 EXPORT_SYMBOL_GPL(ulpi_unregister_driver); 152 153 /* -------------------------------------------------------------------------- */ 154 155 static int ulpi_register(struct device *dev, struct ulpi *ulpi) 156 { 157 int ret; 158 159 /* Test the interface */ 160 ret = ulpi_write(ulpi, ULPI_SCRATCH, 0xaa); 161 if (ret < 0) 162 return ret; 163 164 ret = ulpi_read(ulpi, ULPI_SCRATCH); 165 if (ret < 0) 166 return ret; 167 168 if (ret != 0xaa) 169 return -ENODEV; 170 171 ulpi->id.vendor = ulpi_read(ulpi, ULPI_VENDOR_ID_LOW); 172 ulpi->id.vendor |= ulpi_read(ulpi, ULPI_VENDOR_ID_HIGH) << 8; 173 174 ulpi->id.product = ulpi_read(ulpi, ULPI_PRODUCT_ID_LOW); 175 ulpi->id.product |= ulpi_read(ulpi, ULPI_PRODUCT_ID_HIGH) << 8; 176 177 ulpi->dev.parent = dev; 178 ulpi->dev.bus = &ulpi_bus; 179 ulpi->dev.type = &ulpi_dev_type; 180 dev_set_name(&ulpi->dev, "%s.ulpi", dev_name(dev)); 181 182 ACPI_COMPANION_SET(&ulpi->dev, ACPI_COMPANION(dev)); 183 184 request_module("ulpi:v%04xp%04x", ulpi->id.vendor, ulpi->id.product); 185 186 ret = device_register(&ulpi->dev); 187 if (ret) 188 return ret; 189 190 dev_dbg(&ulpi->dev, "registered ULPI PHY: vendor %04x, product %04x\n", 191 ulpi->id.vendor, ulpi->id.product); 192 193 return 0; 194 } 195 196 /** 197 * ulpi_register_interface - instantiate new ULPI device 198 * @dev: USB controller's device interface 199 * @ops: ULPI register access 200 * 201 * Allocates and registers a ULPI device and an interface for it. Called from 202 * the USB controller that provides the ULPI interface. 203 */ 204 struct ulpi *ulpi_register_interface(struct device *dev, struct ulpi_ops *ops) 205 { 206 struct ulpi *ulpi; 207 int ret; 208 209 ulpi = kzalloc(sizeof(*ulpi), GFP_KERNEL); 210 if (!ulpi) 211 return ERR_PTR(-ENOMEM); 212 213 ulpi->ops = ops; 214 ops->dev = dev; 215 216 ret = ulpi_register(dev, ulpi); 217 if (ret) { 218 kfree(ulpi); 219 return ERR_PTR(ret); 220 } 221 222 return ulpi; 223 } 224 EXPORT_SYMBOL_GPL(ulpi_register_interface); 225 226 /** 227 * ulpi_unregister_interface - unregister ULPI interface 228 * @intrf: struct ulpi_interface 229 * 230 * Unregisters a ULPI device and it's interface that was created with 231 * ulpi_create_interface(). 232 */ 233 void ulpi_unregister_interface(struct ulpi *ulpi) 234 { 235 device_unregister(&ulpi->dev); 236 } 237 EXPORT_SYMBOL_GPL(ulpi_unregister_interface); 238 239 /* -------------------------------------------------------------------------- */ 240 241 static int __init ulpi_init(void) 242 { 243 return bus_register(&ulpi_bus); 244 } 245 subsys_initcall(ulpi_init); 246 247 static void __exit ulpi_exit(void) 248 { 249 bus_unregister(&ulpi_bus); 250 } 251 module_exit(ulpi_exit); 252 253 MODULE_AUTHOR("Intel Corporation"); 254 MODULE_LICENSE("GPL v2"); 255 MODULE_DESCRIPTION("USB ULPI PHY bus"); 256