1 /* 2 * DIO Driver Services 3 * 4 * Copyright (C) 2004 Jochen Friedrich 5 * 6 * Loosely based on drivers/pci/pci-driver.c and drivers/zorro/zorro-driver.c 7 * 8 * This file is subject to the terms and conditions of the GNU General Public 9 * License. See the file COPYING in the main directory of this archive 10 * for more details. 11 */ 12 13 #include <linux/init.h> 14 #include <linux/module.h> 15 #include <linux/dio.h> 16 17 18 /** 19 * dio_match_device - Tell if a DIO device structure has a matching 20 * DIO device id structure 21 * @ids: array of DIO device id structures to search in 22 * @dev: the DIO device structure to match against 23 * 24 * Used by a driver to check whether a DIO device present in the 25 * system is in its list of supported devices. Returns the matching 26 * dio_device_id structure or %NULL if there is no match. 27 */ 28 29 const struct dio_device_id * 30 dio_match_device(const struct dio_device_id *ids, 31 const struct dio_dev *d) 32 { 33 while (ids->id) { 34 if (ids->id == DIO_WILDCARD) 35 return ids; 36 if (DIO_NEEDSSECID(ids->id & 0xff)) { 37 if (ids->id == d->id) 38 return ids; 39 } else { 40 if ((ids->id & 0xff) == (d->id & 0xff)) 41 return ids; 42 } 43 ids++; 44 } 45 return NULL; 46 } 47 48 static int dio_device_probe(struct device *dev) 49 { 50 int error = 0; 51 struct dio_driver *drv = to_dio_driver(dev->driver); 52 struct dio_dev *d = to_dio_dev(dev); 53 54 if (!d->driver && drv->probe) { 55 const struct dio_device_id *id; 56 57 id = dio_match_device(drv->id_table, d); 58 if (id) 59 error = drv->probe(d, id); 60 if (error >= 0) { 61 d->driver = drv; 62 error = 0; 63 } 64 } 65 return error; 66 } 67 68 69 /** 70 * dio_register_driver - register a new DIO driver 71 * @drv: the driver structure to register 72 * 73 * Adds the driver structure to the list of registered drivers 74 * Returns the number of DIO devices which were claimed by the driver 75 * during registration. The driver remains registered even if the 76 * return value is zero. 77 */ 78 79 int dio_register_driver(struct dio_driver *drv) 80 { 81 int count = 0; 82 83 /* initialize common driver fields */ 84 drv->driver.name = drv->name; 85 drv->driver.bus = &dio_bus_type; 86 drv->driver.probe = dio_device_probe; 87 88 /* register with core */ 89 count = driver_register(&drv->driver); 90 return count ? count : 1; 91 } 92 93 94 /** 95 * dio_unregister_driver - unregister a DIO driver 96 * @drv: the driver structure to unregister 97 * 98 * Deletes the driver structure from the list of registered DIO drivers, 99 * gives it a chance to clean up by calling its remove() function for 100 * each device it was responsible for, and marks those devices as 101 * driverless. 102 */ 103 104 void dio_unregister_driver(struct dio_driver *drv) 105 { 106 driver_unregister(&drv->driver); 107 } 108 109 110 /** 111 * dio_bus_match - Tell if a DIO device structure has a matching DIO 112 * device id structure 113 * @ids: array of DIO device id structures to search in 114 * @dev: the DIO device structure to match against 115 * 116 * Used by a driver to check whether a DIO device present in the 117 * system is in its list of supported devices. Returns the matching 118 * dio_device_id structure or %NULL if there is no match. 119 */ 120 121 static int dio_bus_match(struct device *dev, struct device_driver *drv) 122 { 123 struct dio_dev *d = to_dio_dev(dev); 124 struct dio_driver *dio_drv = to_dio_driver(drv); 125 const struct dio_device_id *ids = dio_drv->id_table; 126 127 if (!ids) 128 return 0; 129 130 while (ids->id) { 131 if (ids->id == DIO_WILDCARD) 132 return 1; 133 if (DIO_NEEDSSECID(ids->id & 0xff)) { 134 if (ids->id == d->id) 135 return 1; 136 } else { 137 if ((ids->id & 0xff) == (d->id & 0xff)) 138 return 1; 139 } 140 ids++; 141 } 142 return 0; 143 } 144 145 146 struct bus_type dio_bus_type = { 147 .name = "dio", 148 .match = dio_bus_match 149 }; 150 151 152 static int __init dio_driver_init(void) 153 { 154 return bus_register(&dio_bus_type); 155 } 156 157 postcore_initcall(dio_driver_init); 158 159 EXPORT_SYMBOL(dio_match_device); 160 EXPORT_SYMBOL(dio_register_driver); 161 EXPORT_SYMBOL(dio_unregister_driver); 162 EXPORT_SYMBOL(dio_dev_driver); 163 EXPORT_SYMBOL(dio_bus_type); 164