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 87 /* register with core */ 88 count = driver_register(&drv->driver); 89 return count ? count : 1; 90 } 91 92 93 /** 94 * dio_unregister_driver - unregister a DIO driver 95 * @drv: the driver structure to unregister 96 * 97 * Deletes the driver structure from the list of registered DIO drivers, 98 * gives it a chance to clean up by calling its remove() function for 99 * each device it was responsible for, and marks those devices as 100 * driverless. 101 */ 102 103 void dio_unregister_driver(struct dio_driver *drv) 104 { 105 driver_unregister(&drv->driver); 106 } 107 108 109 /** 110 * dio_bus_match - Tell if a DIO device structure has a matching DIO 111 * device id structure 112 * @ids: array of DIO device id structures to search in 113 * @dev: the DIO device structure to match against 114 * 115 * Used by a driver to check whether a DIO device present in the 116 * system is in its list of supported devices. Returns the matching 117 * dio_device_id structure or %NULL if there is no match. 118 */ 119 120 static int dio_bus_match(struct device *dev, struct device_driver *drv) 121 { 122 struct dio_dev *d = to_dio_dev(dev); 123 struct dio_driver *dio_drv = to_dio_driver(drv); 124 const struct dio_device_id *ids = dio_drv->id_table; 125 126 if (!ids) 127 return 0; 128 129 while (ids->id) { 130 if (ids->id == DIO_WILDCARD) 131 return 1; 132 if (DIO_NEEDSSECID(ids->id & 0xff)) { 133 if (ids->id == d->id) 134 return 1; 135 } else { 136 if ((ids->id & 0xff) == (d->id & 0xff)) 137 return 1; 138 } 139 ids++; 140 } 141 return 0; 142 } 143 144 145 struct bus_type dio_bus_type = { 146 .name = "dio", 147 .match = dio_bus_match, 148 .probe = dio_device_probe, 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