drivers/fmc/fmc-core.c

   1 /*
   2  * Copyright (C) 2012 CERN (www.cern.ch)
   3  * Author: Alessandro Rubini <rubini@gnudd.com>
   4  *
   5  * Released according to the GNU GPL, version 2 or any later version.
   6  *
   7  * This work is part of the White Rabbit project, a research effort led
   8  * by CERN, the European Institute for Nuclear Research.
   9  */
  10 #include <linux/kernel.h>
  11 #include <linux/module.h>
  12 #include <linux/slab.h>
  13 #include <linux/init.h>
  14 #include <linux/device.h>
  15 #include <linux/fmc.h>
  16
  17 static int fmc_check_version(unsigned long version, const char *name)
  18 {
  19         if (__FMC_MAJOR(version) != FMC_MAJOR) {
  20                 pr_err("%s: \"%s\" has wrong major (has %li, expected %i)\n",
  21                        __func__, name, __FMC_MAJOR(version), FMC_MAJOR);
  22                 return -EINVAL;
  23         }
  24
  25         if (__FMC_MINOR(version) != FMC_MINOR)
  26                 pr_info("%s: \"%s\" has wrong minor (has %li, expected %i)\n",
  27                        __func__, name, __FMC_MINOR(version), FMC_MINOR);
  28         return 0;
  29 }
  30
  31 static int fmc_uevent(struct device *dev, struct kobj_uevent_env *env)
  32 {
  33         /* struct fmc_device *fdev = to_fmc_device(dev); */
  34
  35         /* FIXME: The MODALIAS */
  36         add_uevent_var(env, "MODALIAS=%s", "fmc");
  37         return 0;
  38 }
  39
  40 static int fmc_probe(struct device *dev)
  41 {
  42         struct fmc_driver *fdrv = to_fmc_driver(dev->driver);
  43         struct fmc_device *fdev = to_fmc_device(dev);
  44
  45         return fdrv->probe(fdev);
  46 }
  47
  48 static int fmc_remove(struct device *dev)
  49 {
  50         struct fmc_driver *fdrv = to_fmc_driver(dev->driver);
  51         struct fmc_device *fdev = to_fmc_device(dev);
  52
  53         return fdrv->remove(fdev);
  54 }
  55
  56 static void fmc_shutdown(struct device *dev)
  57 {
  58         /* not implemented but mandatory */
  59 }
  60
  61 static struct bus_type fmc_bus_type = {
  62         .name = "fmc",
  63         .match = fmc_match,
  64         .uevent = fmc_uevent,
  65         .probe = fmc_probe,
  66         .remove = fmc_remove,
  67         .shutdown = fmc_shutdown,
  68 };
  69
  70 static void fmc_release(struct device *dev)
  71 {
  72         struct fmc_device *fmc = container_of(dev, struct fmc_device, dev);
  73
  74         kfree(fmc);
  75 }
  76
  77 /*
  78  * The eeprom is exported in sysfs, through a binary attribute
  79  */
  80
  81 static ssize_t fmc_read_eeprom(struct file *file, struct kobject *kobj,
  82                            struct bin_attribute *bin_attr,
  83                            char *buf, loff_t off, size_t count)
  84 {
  85         struct device *dev;
  86         struct fmc_device *fmc;
  87         int eelen;
  88
  89         dev = container_of(kobj, struct device, kobj);
  90         fmc = container_of(dev, struct fmc_device, dev);
  91         eelen = fmc->eeprom_len;
  92         if (off > eelen)
  93                 return -ESPIPE;
  94         if (off == eelen)
  95                 return 0; /* EOF */
  96         if (off + count > eelen)
  97                 count = eelen - off;
  98         memcpy(buf, fmc->eeprom + off, count);
  99         return count;
 100 }
 101
 102 static ssize_t fmc_write_eeprom(struct file *file, struct kobject *kobj,
 103                                 struct bin_attribute *bin_attr,
 104                                 char *buf, loff_t off, size_t count)
 105 {
 106         struct device *dev;
 107         struct fmc_device *fmc;
 108
 109         dev = container_of(kobj, struct device, kobj);
 110         fmc = container_of(dev, struct fmc_device, dev);
 111         return fmc->op->write_ee(fmc, off, buf, count);
 112 }
 113
 114 static struct bin_attribute fmc_eeprom_attr = {
 115         .attr = { .name = "eeprom", .mode = S_IRUGO | S_IWUSR, },
 116         .size = 8192, /* more or less standard */
 117         .read = fmc_read_eeprom,
 118         .write = fmc_write_eeprom,
 119 };
 120
 121 /*
 122  * Functions for client modules follow
 123  */
 124
 125 int fmc_driver_register(struct fmc_driver *drv)
 126 {
 127         if (fmc_check_version(drv->version, drv->driver.name))
 128                 return -EINVAL;
 129         drv->driver.bus = &fmc_bus_type;
 130         return driver_register(&drv->driver);
 131 }
 132 EXPORT_SYMBOL(fmc_driver_register);
 133
 134 void fmc_driver_unregister(struct fmc_driver *drv)
 135 {
 136         driver_unregister(&drv->driver);
 137 }
 138 EXPORT_SYMBOL(fmc_driver_unregister);
 139
 140 /*
 141  * When a device set is registered, all eeproms must be read
 142  * and all FRUs must be parsed
 143  */
 144 int fmc_device_register_n(struct fmc_device **devs, int n)
 145 {
 146         struct fmc_device *fmc, **devarray;
 147         uint32_t device_id;
 148         int i, ret = 0;
 149
 150         if (n < 1)
 151                 return 0;
 152
 153         /* Check the version of the first data structure (function prints) */
 154         if (fmc_check_version(devs[0]->version, devs[0]->carrier_name))
 155                 return -EINVAL;
 156
 157         devarray = kmemdup(devs, n * sizeof(*devs), GFP_KERNEL);
 158         if (!devarray)
 159                 return -ENOMEM;
 160
 161         /* Make all other checks before continuing, for all devices */
 162         for (i = 0; i < n; i++) {
 163                 fmc = devarray[i];
 164                 if (!fmc->hwdev) {
 165                         pr_err("%s: device nr. %i has no hwdev pointer\n",
 166                                __func__, i);
 167                         ret = -EINVAL;
 168                         break;
 169                 }
 170                 if (fmc->flags & FMC_DEVICE_NO_MEZZANINE) {
 171                         dev_info(fmc->hwdev, "absent mezzanine in slot %d\n",
 172                                  fmc->slot_id);
 173                         continue;
 174                 }
 175                 if (!fmc->eeprom) {
 176                         dev_err(fmc->hwdev, "no eeprom provided for slot %i\n",
 177                                 fmc->slot_id);
 178                         ret = -EINVAL;
 179                 }
 180                 if (!fmc->eeprom_addr) {
 181                         dev_err(fmc->hwdev, "no eeprom_addr for slot %i\n",
 182                                 fmc->slot_id);
 183                         ret = -EINVAL;
 184                 }
 185                 if (!fmc->carrier_name || !fmc->carrier_data ||
 186                     !fmc->device_id) {
 187                         dev_err(fmc->hwdev,
 188                                 "deivce nr %i: carrier name, "
 189                                 "data or dev_id not set\n", i);
 190                         ret = -EINVAL;
 191                 }
 192                 if (ret)
 193                         break;
 194
 195         }
 196         if (ret) {
 197                 kfree(devarray);
 198                 return ret;
 199         }
 200
 201         /* Validation is ok. Now init and register the devices */
 202         for (i = 0; i < n; i++) {
 203                 fmc = devarray[i];
 204
 205                 fmc->nr_slots = n; /* each slot must know how many are there */
 206                 fmc->devarray = devarray;
 207
 208                 device_initialize(&fmc->dev);
 209                 fmc->dev.release = fmc_release;
 210                 fmc->dev.parent = fmc->hwdev;
 211
 212                 /* Fill the identification stuff (may fail) */
 213                 fmc_fill_id_info(fmc);
 214
 215                 fmc->dev.bus = &fmc_bus_type;
 216
 217                 /* Name from mezzanine info or carrier info. Or 0,1,2.. */
 218                 device_id = fmc->device_id;
 219                 if (!fmc->mezzanine_name)
 220                         dev_set_name(&fmc->dev, "fmc-%04x", device_id);
 221                 else
 222                         dev_set_name(&fmc->dev, "%s-%04x", fmc->mezzanine_name,
 223                                      device_id);
 224                 ret = device_add(&fmc->dev);
 225                 if (ret < 0) {
 226                         dev_err(fmc->hwdev, "Slot %i: Failed in registering "
 227                                 "\"%s\"\n", fmc->slot_id, fmc->dev.kobj.name);
 228                         goto out;
 229                 }
 230                 ret = sysfs_create_bin_file(&fmc->dev.kobj, &fmc_eeprom_attr);
 231                 if (ret < 0) {
 232                         dev_err(&fmc->dev, "Failed in registering eeprom\n");
 233                         goto out1;
 234                 }
 235                 /* This device went well, give information to the user */
 236                 fmc_dump_eeprom(fmc);
 237                 fmc_dump_sdb(fmc);
 238         }
 239         return 0;
 240
 241 out1:
 242         device_del(&fmc->dev);
 243 out:
 244         fmc_free_id_info(fmc);
 245         put_device(&fmc->dev);
 246
 247         kfree(devarray);
 248         for (i--; i >= 0; i--) {
 249                 sysfs_remove_bin_file(&devs[i]->dev.kobj, &fmc_eeprom_attr);
 250                 device_del(&devs[i]->dev);
 251                 fmc_free_id_info(devs[i]);
 252                 put_device(&devs[i]->dev);
 253         }
 254         return ret;
 255
 256 }
 257 EXPORT_SYMBOL(fmc_device_register_n);
 258
 259 int fmc_device_register(struct fmc_device *fmc)
 260 {
 261         return fmc_device_register_n(&fmc, 1);
 262 }
 263 EXPORT_SYMBOL(fmc_device_register);
 264
 265 void fmc_device_unregister_n(struct fmc_device **devs, int n)
 266 {
 267         int i;
 268
 269         if (n < 1)
 270                 return;
 271
 272         /* Free devarray first, not used by the later loop */
 273         kfree(devs[0]->devarray);
 274
 275         for (i = 0; i < n; i++) {
 276                 sysfs_remove_bin_file(&devs[i]->dev.kobj, &fmc_eeprom_attr);
 277                 device_del(&devs[i]->dev);
 278                 fmc_free_id_info(devs[i]);
 279                 put_device(&devs[i]->dev);
 280         }
 281 }
 282 EXPORT_SYMBOL(fmc_device_unregister_n);
 283
 284 void fmc_device_unregister(struct fmc_device *fmc)
 285 {
 286         fmc_device_unregister_n(&fmc, 1);
 287 }
 288 EXPORT_SYMBOL(fmc_device_unregister);
 289
 290 /* Init and exit are trivial */
 291 static int fmc_init(void)
 292 {
 293         return bus_register(&fmc_bus_type);
 294 }
 295
 296 static void fmc_exit(void)
 297 {
 298         bus_unregister(&fmc_bus_type);
 299 }
 300
 301 module_init(fmc_init);
 302 module_exit(fmc_exit);
 303
 304 MODULE_LICENSE("GPL");