drivers/rapidio/rio-driver.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * RapidIO driver support
   4  *
   5  * Copyright 2005 MontaVista Software, Inc.
   6  * Matt Porter <mporter@kernel.crashing.org>
   7  */
   8
   9 #include <linux/init.h>
  10 #include <linux/module.h>
  11 #include <linux/rio.h>
  12 #include <linux/rio_ids.h>
  13 #include <linux/rio_drv.h>
  14
  15 #include "rio.h"
  16
  17 /**
  18  *  rio_match_device - Tell if a RIO device has a matching RIO device id structure
  19  *  @id: the RIO device id structure to match against
  20  *  @rdev: the RIO device structure to match against
  21  *
  22  *  Used from driver probe and bus matching to check whether a RIO device
  23  *  matches a device id structure provided by a RIO driver. Returns the
  24  *  matching &struct rio_device_id or %NULL if there is no match.
  25  */
  26 static const struct rio_device_id *rio_match_device(const struct rio_device_id
  27                                                     *id,
  28                                                     const struct rio_dev *rdev)
  29 {
  30         while (id->vid || id->asm_vid) {
  31                 if (((id->vid == RIO_ANY_ID) || (id->vid == rdev->vid)) &&
  32                     ((id->did == RIO_ANY_ID) || (id->did == rdev->did)) &&
  33                     ((id->asm_vid == RIO_ANY_ID)
  34                      || (id->asm_vid == rdev->asm_vid))
  35                     && ((id->asm_did == RIO_ANY_ID)
  36                         || (id->asm_did == rdev->asm_did)))
  37                         return id;
  38                 id++;
  39         }
  40         return NULL;
  41 }
  42
  43 /**
  44  * rio_dev_get - Increments the reference count of the RIO device structure
  45  *
  46  * @rdev: RIO device being referenced
  47  *
  48  * Each live reference to a device should be refcounted.
  49  *
  50  * Drivers for RIO devices should normally record such references in
  51  * their probe() methods, when they bind to a device, and release
  52  * them by calling rio_dev_put(), in their disconnect() methods.
  53  */
  54 struct rio_dev *rio_dev_get(struct rio_dev *rdev)
  55 {
  56         if (rdev)
  57                 get_device(&rdev->dev);
  58
  59         return rdev;
  60 }
  61
  62 /**
  63  * rio_dev_put - Release a use of the RIO device structure
  64  *
  65  * @rdev: RIO device being disconnected
  66  *
  67  * Must be called when a user of a device is finished with it.
  68  * When the last user of the device calls this function, the
  69  * memory of the device is freed.
  70  */
  71 void rio_dev_put(struct rio_dev *rdev)
  72 {
  73         if (rdev)
  74                 put_device(&rdev->dev);
  75 }
  76
  77 /**
  78  *  rio_device_probe - Tell if a RIO device structure has a matching RIO device id structure
  79  *  @dev: the RIO device structure to match against
  80  *
  81  * return 0 and set rio_dev->driver when drv claims rio_dev, else error
  82  */
  83 static int rio_device_probe(struct device *dev)
  84 {
  85         struct rio_driver *rdrv = to_rio_driver(dev->driver);
  86         struct rio_dev *rdev = to_rio_dev(dev);
  87         int error = -ENODEV;
  88         const struct rio_device_id *id;
  89
  90         if (!rdev->driver && rdrv->probe) {
  91                 if (!rdrv->id_table)
  92                         return error;
  93                 id = rio_match_device(rdrv->id_table, rdev);
  94                 rio_dev_get(rdev);
  95                 if (id)
  96                         error = rdrv->probe(rdev, id);
  97                 if (error >= 0) {
  98                         rdev->driver = rdrv;
  99                         error = 0;
 100                 } else
 101                         rio_dev_put(rdev);
 102         }
 103         return error;
 104 }
 105
 106 /**
 107  *  rio_device_remove - Remove a RIO device from the system
 108  *
 109  *  @dev: the RIO device structure to match against
 110  *
 111  * Remove a RIO device from the system. If it has an associated
 112  * driver, then run the driver remove() method.  Then update
 113  * the reference count.
 114  */
 115 static int rio_device_remove(struct device *dev)
 116 {
 117         struct rio_dev *rdev = to_rio_dev(dev);
 118         struct rio_driver *rdrv = rdev->driver;
 119
 120         if (rdrv) {
 121                 if (rdrv->remove)
 122                         rdrv->remove(rdev);
 123                 rdev->driver = NULL;
 124         }
 125
 126         rio_dev_put(rdev);
 127
 128         return 0;
 129 }
 130
 131 static void rio_device_shutdown(struct device *dev)
 132 {
 133         struct rio_dev *rdev = to_rio_dev(dev);
 134         struct rio_driver *rdrv = rdev->driver;
 135
 136         dev_dbg(dev, "RIO: %s\n", __func__);
 137
 138         if (rdrv && rdrv->shutdown)
 139                 rdrv->shutdown(rdev);
 140 }
 141
 142 /**
 143  *  rio_register_driver - register a new RIO driver
 144  *  @rdrv: the RIO driver structure to register
 145  *
 146  *  Adds a &struct rio_driver to the list of registered drivers.
 147  *  Returns a negative value on error, otherwise 0. If no error
 148  *  occurred, the driver remains registered even if no device
 149  *  was claimed during registration.
 150  */
 151 int rio_register_driver(struct rio_driver *rdrv)
 152 {
 153         /* initialize common driver fields */
 154         rdrv->driver.name = rdrv->name;
 155         rdrv->driver.bus = &rio_bus_type;
 156
 157         /* register with core */
 158         return driver_register(&rdrv->driver);
 159 }
 160
 161 /**
 162  *  rio_unregister_driver - unregister a RIO driver
 163  *  @rdrv: the RIO driver structure to unregister
 164  *
 165  *  Deletes the &struct rio_driver from the list of registered RIO
 166  *  drivers, gives it a chance to clean up by calling its remove()
 167  *  function for each device it was responsible for, and marks those
 168  *  devices as driverless.
 169  */
 170 void rio_unregister_driver(struct rio_driver *rdrv)
 171 {
 172         driver_unregister(&rdrv->driver);
 173 }
 174
 175 void rio_attach_device(struct rio_dev *rdev)
 176 {
 177         rdev->dev.bus = &rio_bus_type;
 178 }
 179 EXPORT_SYMBOL_GPL(rio_attach_device);
 180
 181 /**
 182  *  rio_match_bus - Tell if a RIO device structure has a matching RIO driver device id structure
 183  *  @dev: the standard device structure to match against
 184  *  @drv: the standard driver structure containing the ids to match against
 185  *
 186  *  Used by a driver to check whether a RIO device present in the
 187  *  system is in its list of supported devices. Returns 1 if
 188  *  there is a matching &struct rio_device_id or 0 if there is
 189  *  no match.
 190  */
 191 static int rio_match_bus(struct device *dev, struct device_driver *drv)
 192 {
 193         struct rio_dev *rdev = to_rio_dev(dev);
 194         struct rio_driver *rdrv = to_rio_driver(drv);
 195         const struct rio_device_id *id = rdrv->id_table;
 196         const struct rio_device_id *found_id;
 197
 198         if (!id)
 199                 goto out;
 200
 201         found_id = rio_match_device(id, rdev);
 202
 203         if (found_id)
 204                 return 1;
 205
 206       out:return 0;
 207 }
 208
 209 static int rio_uevent(struct device *dev, struct kobj_uevent_env *env)
 210 {
 211         struct rio_dev *rdev;
 212
 213         if (!dev)
 214                 return -ENODEV;
 215
 216         rdev = to_rio_dev(dev);
 217         if (!rdev)
 218                 return -ENODEV;
 219
 220         if (add_uevent_var(env, "MODALIAS=rapidio:v%04Xd%04Xav%04Xad%04X",
 221                            rdev->vid, rdev->did, rdev->asm_vid, rdev->asm_did))
 222                 return -ENOMEM;
 223         return 0;
 224 }
 225
 226 struct class rio_mport_class = {
 227         .name           = "rapidio_port",
 228         .owner          = THIS_MODULE,
 229         .dev_groups     = rio_mport_groups,
 230 };
 231 EXPORT_SYMBOL_GPL(rio_mport_class);
 232
 233 struct bus_type rio_bus_type = {
 234         .name = "rapidio",
 235         .match = rio_match_bus,
 236         .dev_groups = rio_dev_groups,
 237         .bus_groups = rio_bus_groups,
 238         .probe = rio_device_probe,
 239         .remove = rio_device_remove,
 240         .shutdown = rio_device_shutdown,
 241         .uevent = rio_uevent,
 242 };
 243
 244 /**
 245  *  rio_bus_init - Register the RapidIO bus with the device model
 246  *
 247  *  Registers the RIO mport device class and RIO bus type with the Linux
 248  *  device model.
 249  */
 250 static int __init rio_bus_init(void)
 251 {
 252         int ret;
 253
 254         ret = class_register(&rio_mport_class);
 255         if (!ret) {
 256                 ret = bus_register(&rio_bus_type);
 257                 if (ret)
 258                         class_unregister(&rio_mport_class);
 259         }
 260         return ret;
 261 }
 262
 263 postcore_initcall(rio_bus_init);
 264
 265 EXPORT_SYMBOL_GPL(rio_register_driver);
 266 EXPORT_SYMBOL_GPL(rio_unregister_driver);
 267 EXPORT_SYMBOL_GPL(rio_bus_type);
 268 EXPORT_SYMBOL_GPL(rio_dev_get);
 269 EXPORT_SYMBOL_GPL(rio_dev_put);