drivers/media/dvb/dvb-core/dvbdev.c

   1 /*
   2  * dvbdev.c
   3  *
   4  * Copyright (C) 2000 Ralph  Metzler <ralph@convergence.de>
   5  *                  & Marcus Metzler <marcus@convergence.de>
   6  *                    for convergence integrated media GmbH
   7  *
   8  * This program is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU Lesser General Public License
  10  * as published by the Free Software Foundation; either version 2.1
  11  * of the License, or (at your option) any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU Lesser General Public License
  19  * along with this program; if not, write to the Free Software
  20  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
  21  *
  22  */
  23
  24 #include <asm/types.h>
  25 #include <asm/semaphore.h>
  26 #include <linux/errno.h>
  27 #include <linux/string.h>
  28 #include <linux/module.h>
  29 #include <linux/kernel.h>
  30 #include <linux/sched.h>
  31 #include <linux/init.h>
  32 #include <linux/slab.h>
  33 #include <linux/version.h>
  34
  35 #include "dvbdev.h"
  36 #include "dvb_functions.h"
  37
  38 static int dvbdev_debug = 0;
  39 #define dprintk if (dvbdev_debug) printk
  40
  41 static LIST_HEAD(dvb_adapter_list);
  42 static DECLARE_MUTEX(dvbdev_register_lock);
  43
  44
  45 static char *dnames[] = {
  46         "video", "audio", "sec", "frontend", "demux", "dvr", "ca",
  47         "net", "osd"
  48 };
  49
  50
  51 #define DVB_MAX_IDS              4
  52 #define nums2minor(num,type,id)  ((num << 6) | (id << 4) | type)
  53
  54 static
  55 struct dvb_device* dvbdev_find_device (int minor)
  56 {
  57         struct list_head *entry;
  58
  59         list_for_each (entry, &dvb_adapter_list) {
  60                 struct list_head *entry0;
  61                 struct dvb_adapter *adap;
  62                 adap = list_entry (entry, struct dvb_adapter, list_head);
  63                 list_for_each (entry0, &adap->device_list) {
  64                         struct dvb_device *dev;
  65                         dev = list_entry (entry0, struct dvb_device, list_head);
  66                         if (nums2minor(adap->num, dev->type, dev->id) == minor)
  67                                 return dev;
  68                 }
  69         }
  70
  71         return NULL;
  72 }
  73
  74
  75 static
  76 int dvb_device_open(struct inode *inode, struct file *file)
  77 {
  78         struct dvb_device *dvbdev;
  79
  80         dvbdev = dvbdev_find_device (minor(inode->i_rdev));
  81
  82         if (dvbdev && dvbdev->fops) {
  83                 int err = 0;
  84                 struct file_operations *old_fops;
  85
  86                 file->private_data = dvbdev;
  87                 old_fops = file->f_op;
  88                 file->f_op = fops_get(dvbdev->fops);
  89                 if(file->f_op->open)
  90                         err = file->f_op->open(inode,file);
  91                 if (err) {
  92                         fops_put(file->f_op);
  93                         file->f_op = fops_get(old_fops);
  94                 }
  95                 fops_put(old_fops);
  96                 return err;
  97         }
  98         return -ENODEV;
  99 }
 100
 101
 102 static struct file_operations dvb_device_fops =
 103 {
 104         .owner =        THIS_MODULE,
 105         .open =         dvb_device_open,
 106 };
 107
 108
 109 int dvb_generic_open(struct inode *inode, struct file *file)
 110 {
 111         struct dvb_device *dvbdev = file->private_data;
 112
 113         if (!dvbdev)
 114                 return -ENODEV;
 115
 116         if (!dvbdev->users)
 117                 return -EBUSY;
 118
 119         if ((file->f_flags & O_ACCMODE) != O_RDONLY) {
 120                 if (!dvbdev->writers)
 121                         return -EBUSY;
 122                 dvbdev->writers--;
 123         }
 124
 125         dvbdev->users--;
 126         return 0;
 127 }
 128
 129
 130 int dvb_generic_release(struct inode *inode, struct file *file)
 131 {
 132         struct dvb_device *dvbdev = file->private_data;
 133
 134         if (!dvbdev)
 135                 return -ENODEV;
 136
 137         if ((file->f_flags & O_ACCMODE) != O_RDONLY)
 138                 dvbdev->writers++;
 139
 140         dvbdev->users++;
 141         return 0;
 142 }
 143
 144
 145 int dvb_generic_ioctl(struct inode *inode, struct file *file,
 146                       unsigned int cmd, unsigned long arg)
 147 {
 148         struct dvb_device *dvbdev = file->private_data;
 149
 150         if (!dvbdev)
 151                 return -ENODEV;
 152
 153         if (!dvbdev->kernel_ioctl)
 154                 return -EINVAL;
 155
 156         return dvb_usercopy (inode, file, cmd, arg, dvbdev->kernel_ioctl);
 157 }
 158
 159
 160 static
 161 int dvbdev_get_free_id (struct dvb_adapter *adap, int type)
 162 {
 163         u32 id = 0;
 164
 165         while (id < DVB_MAX_IDS) {
 166                 struct list_head *entry;
 167                 list_for_each (entry, &adap->device_list) {
 168                         struct dvb_device *dev;
 169                         dev = list_entry (entry, struct dvb_device, list_head);
 170                         if (dev->type == type && dev->id == id)
 171                                 goto skip;
 172                 }
 173                 return id;
 174 skip:
 175                 id++;
 176         }
 177         return -ENFILE;
 178 }
 179
 180
 181 int dvb_register_device(struct dvb_adapter *adap, struct dvb_device **pdvbdev,
 182                         const struct dvb_device *template, void *priv, int type)
 183 {
 184         struct dvb_device *dvbdev;
 185         int id;
 186
 187         if (down_interruptible (&dvbdev_register_lock))
 188                 return -ERESTARTSYS;
 189
 190         if ((id = dvbdev_get_free_id (adap, type)) < 0) {
 191                 up (&dvbdev_register_lock);
 192                 *pdvbdev = 0;
 193                 printk ("%s: could get find free device id...\n", __FUNCTION__);
 194                 return -ENFILE;
 195         }
 196
 197         *pdvbdev = dvbdev = kmalloc(sizeof(struct dvb_device), GFP_KERNEL);
 198
 199         if (!dvbdev) {
 200                 up(&dvbdev_register_lock);
 201                 return -ENOMEM;
 202         }
 203
 204         up (&dvbdev_register_lock);
 205
 206         memcpy(dvbdev, template, sizeof(struct dvb_device));
 207         dvbdev->type = type;
 208         dvbdev->id = id;
 209         dvbdev->adapter = adap;
 210         dvbdev->priv = priv;
 211
 212         list_add_tail (&dvbdev->list_head, &adap->device_list);
 213
 214         devfs_mk_cdev(MKDEV(DVB_MAJOR, nums2minor(adap->num, type, id)),
 215                         S_IFCHR | S_IRUSR | S_IWUSR,
 216                         "dvb/adapter%d/%s%d", adap->num, dnames[type], id);
 217
 218         dprintk("DVB: register adapter%d/%s%d @ minor: %i (0x%02x)\n",
 219                 adap->num, dnames[type], id, nums2minor(adap->num, type, id),
 220                 nums2minor(adap->num, type, id));
 221
 222         return 0;
 223 }
 224
 225
 226 void dvb_unregister_device(struct dvb_device *dvbdev)
 227 {
 228         if (dvbdev) {
 229                 devfs_remove("dvb/adapter%d/%s%d", dvbdev->adapter->num,
 230                                 dnames[dvbdev->type], dvbdev->id);
 231                 list_del(&dvbdev->list_head);
 232                 kfree(dvbdev);
 233         }
 234 }
 235
 236
 237 static
 238 int dvbdev_get_free_adapter_num (void)
 239 {
 240         int num = 0;
 241
 242         while (1) {
 243                 struct list_head *entry;
 244                 list_for_each (entry, &dvb_adapter_list) {
 245                         struct dvb_adapter *adap;
 246                         adap = list_entry (entry, struct dvb_adapter, list_head);
 247                         if (adap->num == num)
 248                                 goto skip;
 249                 }
 250                 return num;
 251 skip:
 252                 num++;
 253         }
 254
 255         return -ENFILE;
 256 }
 257
 258
 259 int dvb_register_adapter(struct dvb_adapter **padap, const char *name)
 260 {
 261         struct dvb_adapter *adap;
 262         int num;
 263
 264         if (down_interruptible (&dvbdev_register_lock))
 265                 return -ERESTARTSYS;
 266
 267         if ((num = dvbdev_get_free_adapter_num ()) < 0) {
 268                 up (&dvbdev_register_lock);
 269                 return -ENFILE;
 270         }
 271
 272         if (!(*padap = adap = kmalloc(sizeof(struct dvb_adapter), GFP_KERNEL))) {
 273                 up(&dvbdev_register_lock);
 274                 return -ENOMEM;
 275         }
 276
 277         memset (adap, 0, sizeof(struct dvb_adapter));
 278         INIT_LIST_HEAD (&adap->device_list);
 279
 280         printk ("DVB: registering new adapter (%s).\n", name);
 281
 282         devfs_mk_dir("dvb/adapter%d", num);
 283         adap->num = num;
 284         adap->name = name;
 285
 286         list_add_tail (&adap->list_head, &dvb_adapter_list);
 287
 288         up (&dvbdev_register_lock);
 289
 290         return num;
 291 }
 292
 293
 294 int dvb_unregister_adapter(struct dvb_adapter *adap)
 295 {
 296         if (down_interruptible (&dvbdev_register_lock))
 297                 return -ERESTARTSYS;
 298         devfs_remove("dvb/adapter%d", adap->num);
 299         list_del (&adap->list_head);
 300         up (&dvbdev_register_lock);
 301         kfree (adap);
 302         return 0;
 303 }
 304
 305
 306 static
 307 int __init init_dvbdev(void)
 308 {
 309         devfs_mk_dir("dvb");
 310
 311         if(register_chrdev(DVB_MAJOR,"DVB", &dvb_device_fops)) {
 312                 printk("video_dev: unable to get major %d\n", DVB_MAJOR);
 313                 return -EIO;
 314         }
 315
 316         return 0;
 317 }
 318
 319
 320 static
 321 void __exit exit_dvbdev(void)
 322 {
 323         unregister_chrdev(DVB_MAJOR, "DVB");
 324         devfs_remove("dvb");
 325 }
 326
 327 module_init(init_dvbdev);
 328 module_exit(exit_dvbdev);
 329
 330 MODULE_DESCRIPTION("DVB Core Driver");
 331 MODULE_AUTHOR("Marcus Metzler, Ralph Metzler, Holger Waechtler");
 332 MODULE_LICENSE("GPL");
 333
 334 MODULE_PARM(dvbdev_debug,"i");
 335 MODULE_PARM_DESC(dvbdev_debug, "enable verbose debug messages");
 336