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 DIO device id structure 20 * @ids: array of DIO device id structures to search in 21 * @d: the DIO device structure to match against 22 * 23 * Used by a driver to check whether a DIO device present in the 24 * system is in its list of supported devices. Returns the matching 25 * dio_device_id structure or %NULL if there is no match. 26 */ 27 28 static const struct dio_device_id * 29 dio_match_device(const struct dio_device_id *ids, 30 const struct dio_dev *d) 31 { 32 while (ids->id) { 33 if (ids->id == DIO_WILDCARD) 34 return ids; 35 if (DIO_NEEDSSECID(ids->id & 0xff)) { 36 if (ids->id == d->id) 37 return ids; 38 } else { 39 if ((ids->id & 0xff) == (d->id & 0xff)) 40 return ids; 41 } 42 ids++; 43 } 44 return NULL; 45 } 46 47 static int dio_device_probe(struct device *dev) 48 { 49 int error = 0; 50 struct dio_driver *drv = to_dio_driver(dev->driver); 51 struct dio_dev *d = to_dio_dev(dev); 52 53 if (!d->driver && drv->probe) { 54 const struct dio_device_id *id; 55 56 id = dio_match_device(drv->id_table, d); 57 if (id) 58 error = drv->probe(d, id); 59 if (error >= 0) { 60 d->driver = drv; 61 error = 0; 62 } 63 } 64 return error; 65 } 66 67 68 /** 69 * dio_register_driver - register a new DIO driver 70 * @drv: the driver structure to register 71 * 72 * Adds the driver structure to the list of registered drivers 73 * Returns zero or a negative error value. 74 */ 75 76 int dio_register_driver(struct dio_driver *drv) 77 { 78 /* initialize common driver fields */ 79 drv->driver.name = drv->name; 80 drv->driver.bus = &dio_bus_type; 81 82 /* register with core */ 83 return driver_register(&drv->driver); 84 } 85 86 87 /** 88 * dio_unregister_driver - unregister a DIO driver 89 * @drv: the driver structure to unregister 90 * 91 * Deletes the driver structure from the list of registered DIO drivers, 92 * gives it a chance to clean up by calling its remove() function for 93 * each device it was responsible for, and marks those devices as 94 * driverless. 95 */ 96 97 void dio_unregister_driver(struct dio_driver *drv) 98 { 99 driver_unregister(&drv->driver); 100 } 101 102 103 /** 104 * dio_bus_match - Tell if a DIO device structure has a matching DIO device id structure 105 * @dev: the DIO device structure to match against 106 * @drv: the &device_driver that points to the array of DIO device id structures to search 107 * 108 * Used by the driver core to check whether a DIO device present in the 109 * system is in a driver's list of supported devices. Returns 1 if supported, 110 * and 0 if there is no match. 111 */ 112 113 static int dio_bus_match(struct device *dev, struct device_driver *drv) 114 { 115 struct dio_dev *d = to_dio_dev(dev); 116 struct dio_driver *dio_drv = to_dio_driver(drv); 117 const struct dio_device_id *ids = dio_drv->id_table; 118 119 if (!ids) 120 return 0; 121 122 return dio_match_device(ids, d) ? 1 : 0; 123 } 124 125 126 const struct bus_type dio_bus_type = { 127 .name = "dio", 128 .match = dio_bus_match, 129 .probe = dio_device_probe, 130 }; 131 132 133 static int __init dio_driver_init(void) 134 { 135 return bus_register(&dio_bus_type); 136 } 137 138 postcore_initcall(dio_driver_init); 139 140 EXPORT_SYMBOL(dio_register_driver); 141 EXPORT_SYMBOL(dio_unregister_driver); 142 EXPORT_SYMBOL(dio_bus_type); 143