1 /* 2 * drivers/sh/superhyway/superhyway.c 3 * 4 * SuperHyway Bus Driver 5 * 6 * Copyright (C) 2004, 2005 Paul Mundt <lethal@linux-sh.org> 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 #include <linux/kernel.h> 13 #include <linux/device.h> 14 #include <linux/init.h> 15 #include <linux/module.h> 16 #include <linux/types.h> 17 #include <linux/list.h> 18 #include <linux/superhyway.h> 19 #include <linux/string.h> 20 #include <linux/slab.h> 21 22 static int superhyway_devices; 23 24 static struct device superhyway_bus_device = { 25 .init_name = "superhyway", 26 }; 27 28 static void superhyway_device_release(struct device *dev) 29 { 30 struct superhyway_device *sdev = to_superhyway_device(dev); 31 32 kfree(sdev->resource); 33 kfree(sdev); 34 } 35 36 /** 37 * superhyway_add_device - Add a SuperHyway module 38 * @base: Physical address where module is mapped. 39 * @sdev: SuperHyway device to add, or NULL to allocate a new one. 40 * @bus: Bus where SuperHyway module resides. 41 * 42 * This is responsible for adding a new SuperHyway module. This sets up a new 43 * struct superhyway_device for the module being added if @sdev == NULL. 44 * 45 * Devices are initially added in the order that they are scanned (from the 46 * top-down of the memory map), and are assigned an ID based on the order that 47 * they are added. Any manual addition of a module will thus get the ID after 48 * the devices already discovered regardless of where it resides in memory. 49 * 50 * Further work can and should be done in superhyway_scan_bus(), to be sure 51 * that any new modules are properly discovered and subsequently registered. 52 */ 53 int superhyway_add_device(unsigned long base, struct superhyway_device *sdev, 54 struct superhyway_bus *bus) 55 { 56 struct superhyway_device *dev = sdev; 57 58 if (!dev) { 59 dev = kzalloc(sizeof(struct superhyway_device), GFP_KERNEL); 60 if (!dev) 61 return -ENOMEM; 62 63 } 64 65 dev->bus = bus; 66 superhyway_read_vcr(dev, base, &dev->vcr); 67 68 if (!dev->resource) { 69 dev->resource = kzalloc(sizeof(struct resource), GFP_KERNEL); 70 if (!dev->resource) { 71 kfree(dev); 72 return -ENOMEM; 73 } 74 75 dev->resource->name = dev->name; 76 dev->resource->start = base; 77 dev->resource->end = dev->resource->start + 0x01000000; 78 } 79 80 dev->dev.parent = &superhyway_bus_device; 81 dev->dev.bus = &superhyway_bus_type; 82 dev->dev.release = superhyway_device_release; 83 dev->id.id = dev->vcr.mod_id; 84 85 sprintf(dev->name, "SuperHyway device %04x", dev->id.id); 86 dev_set_name(&dev->dev, "%02x", superhyway_devices); 87 88 superhyway_devices++; 89 90 return device_register(&dev->dev); 91 } 92 93 int superhyway_add_devices(struct superhyway_bus *bus, 94 struct superhyway_device **devices, 95 int nr_devices) 96 { 97 int i, ret = 0; 98 99 for (i = 0; i < nr_devices; i++) { 100 struct superhyway_device *dev = devices[i]; 101 ret |= superhyway_add_device(dev->resource[0].start, dev, bus); 102 } 103 104 return ret; 105 } 106 107 static int __init superhyway_init(void) 108 { 109 struct superhyway_bus *bus; 110 int ret; 111 112 ret = device_register(&superhyway_bus_device); 113 if (unlikely(ret)) 114 return ret; 115 116 for (bus = superhyway_channels; bus->ops; bus++) 117 ret |= superhyway_scan_bus(bus); 118 119 return ret; 120 } 121 postcore_initcall(superhyway_init); 122 123 static const struct superhyway_device_id * 124 superhyway_match_id(const struct superhyway_device_id *ids, 125 struct superhyway_device *dev) 126 { 127 while (ids->id) { 128 if (ids->id == dev->id.id) 129 return ids; 130 131 ids++; 132 } 133 134 return NULL; 135 } 136 137 static int superhyway_device_probe(struct device *dev) 138 { 139 struct superhyway_device *shyway_dev = to_superhyway_device(dev); 140 struct superhyway_driver *shyway_drv = to_superhyway_driver(dev->driver); 141 142 if (shyway_drv && shyway_drv->probe) { 143 const struct superhyway_device_id *id; 144 145 id = superhyway_match_id(shyway_drv->id_table, shyway_dev); 146 if (id) 147 return shyway_drv->probe(shyway_dev, id); 148 } 149 150 return -ENODEV; 151 } 152 153 static int superhyway_device_remove(struct device *dev) 154 { 155 struct superhyway_device *shyway_dev = to_superhyway_device(dev); 156 struct superhyway_driver *shyway_drv = to_superhyway_driver(dev->driver); 157 158 if (shyway_drv && shyway_drv->remove) { 159 shyway_drv->remove(shyway_dev); 160 return 0; 161 } 162 163 return -ENODEV; 164 } 165 166 /** 167 * superhyway_register_driver - Register a new SuperHyway driver 168 * @drv: SuperHyway driver to register. 169 * 170 * This registers the passed in @drv. Any devices matching the id table will 171 * automatically be populated and handed off to the driver's specified probe 172 * routine. 173 */ 174 int superhyway_register_driver(struct superhyway_driver *drv) 175 { 176 drv->drv.name = drv->name; 177 drv->drv.bus = &superhyway_bus_type; 178 179 return driver_register(&drv->drv); 180 } 181 182 /** 183 * superhyway_unregister_driver - Unregister a SuperHyway driver 184 * @drv: SuperHyway driver to unregister. 185 * 186 * This cleans up after superhyway_register_driver(), and should be invoked in 187 * the exit path of any module drivers. 188 */ 189 void superhyway_unregister_driver(struct superhyway_driver *drv) 190 { 191 driver_unregister(&drv->drv); 192 } 193 194 static int superhyway_bus_match(struct device *dev, struct device_driver *drv) 195 { 196 struct superhyway_device *shyway_dev = to_superhyway_device(dev); 197 struct superhyway_driver *shyway_drv = to_superhyway_driver(drv); 198 const struct superhyway_device_id *ids = shyway_drv->id_table; 199 200 if (!ids) 201 return -EINVAL; 202 if (superhyway_match_id(ids, shyway_dev)) 203 return 1; 204 205 return -ENODEV; 206 } 207 208 struct bus_type superhyway_bus_type = { 209 .name = "superhyway", 210 .match = superhyway_bus_match, 211 #ifdef CONFIG_SYSFS 212 .dev_groups = superhyway_dev_groups, 213 #endif 214 .probe = superhyway_device_probe, 215 .remove = superhyway_device_remove, 216 }; 217 218 static int __init superhyway_bus_init(void) 219 { 220 return bus_register(&superhyway_bus_type); 221 } 222 223 static void __exit superhyway_bus_exit(void) 224 { 225 device_unregister(&superhyway_bus_device); 226 bus_unregister(&superhyway_bus_type); 227 } 228 229 core_initcall(superhyway_bus_init); 230 module_exit(superhyway_bus_exit); 231 232 EXPORT_SYMBOL(superhyway_bus_type); 233 EXPORT_SYMBOL(superhyway_add_device); 234 EXPORT_SYMBOL(superhyway_add_devices); 235 EXPORT_SYMBOL(superhyway_register_driver); 236 EXPORT_SYMBOL(superhyway_unregister_driver); 237 238 MODULE_LICENSE("GPL"); 239