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 .bus_id = "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 = kmalloc(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 sprintf(dev->dev.bus_id, "%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 = 0; 111 112 device_register(&superhyway_bus_device); 113 114 for (bus = superhyway_channels; bus->ops; bus++) 115 ret |= superhyway_scan_bus(bus); 116 117 return ret; 118 } 119 120 postcore_initcall(superhyway_init); 121 122 static const struct superhyway_device_id * 123 superhyway_match_id(const struct superhyway_device_id *ids, 124 struct superhyway_device *dev) 125 { 126 while (ids->id) { 127 if (ids->id == dev->id.id) 128 return ids; 129 130 ids++; 131 } 132 133 return NULL; 134 } 135 136 static int superhyway_device_probe(struct device *dev) 137 { 138 struct superhyway_device *shyway_dev = to_superhyway_device(dev); 139 struct superhyway_driver *shyway_drv = to_superhyway_driver(dev->driver); 140 141 if (shyway_drv && shyway_drv->probe) { 142 const struct superhyway_device_id *id; 143 144 id = superhyway_match_id(shyway_drv->id_table, shyway_dev); 145 if (id) 146 return shyway_drv->probe(shyway_dev, id); 147 } 148 149 return -ENODEV; 150 } 151 152 static int superhyway_device_remove(struct device *dev) 153 { 154 struct superhyway_device *shyway_dev = to_superhyway_device(dev); 155 struct superhyway_driver *shyway_drv = to_superhyway_driver(dev->driver); 156 157 if (shyway_drv && shyway_drv->remove) { 158 shyway_drv->remove(shyway_dev); 159 return 0; 160 } 161 162 return -ENODEV; 163 } 164 165 /** 166 * superhyway_register_driver - Register a new SuperHyway driver 167 * @drv: SuperHyway driver to register. 168 * 169 * This registers the passed in @drv. Any devices matching the id table will 170 * automatically be populated and handed off to the driver's specified probe 171 * routine. 172 */ 173 int superhyway_register_driver(struct superhyway_driver *drv) 174 { 175 drv->drv.name = drv->name; 176 drv->drv.bus = &superhyway_bus_type; 177 178 return driver_register(&drv->drv); 179 } 180 181 /** 182 * superhyway_unregister_driver - Unregister a SuperHyway driver 183 * @drv: SuperHyway driver to unregister. 184 * 185 * This cleans up after superhyway_register_driver(), and should be invoked in 186 * the exit path of any module drivers. 187 */ 188 void superhyway_unregister_driver(struct superhyway_driver *drv) 189 { 190 driver_unregister(&drv->drv); 191 } 192 193 static int superhyway_bus_match(struct device *dev, struct device_driver *drv) 194 { 195 struct superhyway_device *shyway_dev = to_superhyway_device(dev); 196 struct superhyway_driver *shyway_drv = to_superhyway_driver(drv); 197 const struct superhyway_device_id *ids = shyway_drv->id_table; 198 199 if (!ids) 200 return -EINVAL; 201 if (superhyway_match_id(ids, shyway_dev)) 202 return 1; 203 204 return -ENODEV; 205 } 206 207 struct bus_type superhyway_bus_type = { 208 .name = "superhyway", 209 .match = superhyway_bus_match, 210 #ifdef CONFIG_SYSFS 211 .dev_attrs = superhyway_dev_attrs, 212 #endif 213 .probe = superhyway_device_probe, 214 .remove = superhyway_device_remove, 215 }; 216 217 static int __init superhyway_bus_init(void) 218 { 219 return bus_register(&superhyway_bus_type); 220 } 221 222 static void __exit superhyway_bus_exit(void) 223 { 224 device_unregister(&superhyway_bus_device); 225 bus_unregister(&superhyway_bus_type); 226 } 227 228 core_initcall(superhyway_bus_init); 229 module_exit(superhyway_bus_exit); 230 231 EXPORT_SYMBOL(superhyway_bus_type); 232 EXPORT_SYMBOL(superhyway_add_device); 233 EXPORT_SYMBOL(superhyway_add_devices); 234 EXPORT_SYMBOL(superhyway_register_driver); 235 EXPORT_SYMBOL(superhyway_unregister_driver); 236 237 MODULE_LICENSE("GPL"); 238