drivers/media/IR/ir-sysfs.c

   1 /* ir-sysfs.c - sysfs interface for RC devices (/sys/class/rc)
   2  *
   3  * Copyright (C) 2009-2010 by Mauro Carvalho Chehab <mchehab@redhat.com>
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  *  it under the terms of the GNU General Public License as published by
   7  *  the Free Software Foundation version 2 of the License.
   8  *
   9  *  This program is distributed in the hope that it will be useful,
  10  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  *  GNU General Public License for more details.
  13  */
  14
  15 #include <linux/slab.h>
  16 #include <linux/input.h>
  17 #include <linux/device.h>
  18 #include "ir-core-priv.h"
  19
  20 #define IRRCV_NUM_DEVICES       256
  21
  22 /* bit array to represent IR sysfs device number */
  23 static unsigned long ir_core_dev_number;
  24
  25 /* class for /sys/class/rc */
  26 static char *ir_devnode(struct device *dev, mode_t *mode)
  27 {
  28         return kasprintf(GFP_KERNEL, "rc/%s", dev_name(dev));
  29 }
  30
  31 static struct class ir_input_class = {
  32         .name           = "rc",
  33         .devnode        = ir_devnode,
  34 };
  35
  36 static struct {
  37         u64     type;
  38         char    *name;
  39 } proto_names[] = {
  40         { IR_TYPE_UNKNOWN,      "unknown"       },
  41         { IR_TYPE_RC5,          "rc-5"          },
  42         { IR_TYPE_NEC,          "nec"           },
  43         { IR_TYPE_RC6,          "rc-6"          },
  44         { IR_TYPE_JVC,          "jvc"           },
  45         { IR_TYPE_SONY,         "sony"          },
  46         { IR_TYPE_LIRC,         "lirc"          },
  47 };
  48
  49 #define PROTO_NONE      "none"
  50
  51 /**
  52  * show_protocols() - shows the current IR protocol(s)
  53  * @d:          the device descriptor
  54  * @mattr:      the device attribute struct (unused)
  55  * @buf:        a pointer to the output buffer
  56  *
  57  * This routine is a callback routine for input read the IR protocol type(s).
  58  * it is trigged by reading /sys/class/rc/rc?/protocols.
  59  * It returns the protocol names of supported protocols.
  60  * Enabled protocols are printed in brackets.
  61  */
  62 static ssize_t show_protocols(struct device *d,
  63                               struct device_attribute *mattr, char *buf)
  64 {
  65         struct ir_input_dev *ir_dev = dev_get_drvdata(d);
  66         u64 allowed, enabled;
  67         char *tmp = buf;
  68         int i;
  69
  70         if (ir_dev->props && ir_dev->props->driver_type == RC_DRIVER_SCANCODE) {
  71                 enabled = ir_dev->rc_tab.ir_type;
  72                 allowed = ir_dev->props->allowed_protos;
  73         } else if (ir_dev->raw) {
  74                 enabled = ir_dev->raw->enabled_protocols;
  75                 allowed = ir_raw_get_allowed_protocols();
  76         } else
  77                 return sprintf(tmp, "[builtin]\n");
  78
  79         IR_dprintk(1, "allowed - 0x%llx, enabled - 0x%llx\n",
  80                    (long long)allowed,
  81                    (long long)enabled);
  82
  83         for (i = 0; i < ARRAY_SIZE(proto_names); i++) {
  84                 if (allowed & enabled & proto_names[i].type)
  85                         tmp += sprintf(tmp, "[%s] ", proto_names[i].name);
  86                 else if (allowed & proto_names[i].type)
  87                         tmp += sprintf(tmp, "%s ", proto_names[i].name);
  88         }
  89
  90         if (tmp != buf)
  91                 tmp--;
  92         *tmp = '\n';
  93         return tmp + 1 - buf;
  94 }
  95
  96 /**
  97  * store_protocols() - changes the current IR protocol(s)
  98  * @d:          the device descriptor
  99  * @mattr:      the device attribute struct (unused)
 100  * @buf:        a pointer to the input buffer
 101  * @len:        length of the input buffer
 102  *
 103  * This routine is a callback routine for changing the IR protocol type.
 104  * It is trigged by writing to /sys/class/rc/rc?/protocols.
 105  * Writing "+proto" will add a protocol to the list of enabled protocols.
 106  * Writing "-proto" will remove a protocol from the list of enabled protocols.
 107  * Writing "proto" will enable only "proto".
 108  * Writing "none" will disable all protocols.
 109  * Returns -EINVAL if an invalid protocol combination or unknown protocol name
 110  * is used, otherwise @len.
 111  */
 112 static ssize_t store_protocols(struct device *d,
 113                                struct device_attribute *mattr,
 114                                const char *data,
 115                                size_t len)
 116 {
 117         struct ir_input_dev *ir_dev = dev_get_drvdata(d);
 118         bool enable, disable;
 119         const char *tmp;
 120         u64 type;
 121         u64 mask;
 122         int rc, i, count = 0;
 123         unsigned long flags;
 124
 125         if (ir_dev->props && ir_dev->props->driver_type == RC_DRIVER_SCANCODE)
 126                 type = ir_dev->rc_tab.ir_type;
 127         else if (ir_dev->raw)
 128                 type = ir_dev->raw->enabled_protocols;
 129         else {
 130                 IR_dprintk(1, "Protocol switching not supported\n");
 131                 return -EINVAL;
 132         }
 133
 134         while ((tmp = strsep((char **) &data, " \n")) != NULL) {
 135                 if (!*tmp)
 136                         break;
 137
 138                 if (*tmp == '+') {
 139                         enable = true;
 140                         disable = false;
 141                         tmp++;
 142                 } else if (*tmp == '-') {
 143                         enable = false;
 144                         disable = true;
 145                         tmp++;
 146                 } else {
 147                         enable = false;
 148                         disable = false;
 149                 }
 150
 151                 if (!enable && !disable && !strncasecmp(tmp, PROTO_NONE, sizeof(PROTO_NONE))) {
 152                         tmp += sizeof(PROTO_NONE);
 153                         mask = 0;
 154                         count++;
 155                 } else {
 156                         for (i = 0; i < ARRAY_SIZE(proto_names); i++) {
 157                                 if (!strncasecmp(tmp, proto_names[i].name, strlen(proto_names[i].name))) {
 158                                         tmp += strlen(proto_names[i].name);
 159                                         mask = proto_names[i].type;
 160                                         break;
 161                                 }
 162                         }
 163                         if (i == ARRAY_SIZE(proto_names)) {
 164                                 IR_dprintk(1, "Unknown protocol: '%s'\n", tmp);
 165                                 return -EINVAL;
 166                         }
 167                         count++;
 168                 }
 169
 170                 if (enable)
 171                         type |= mask;
 172                 else if (disable)
 173                         type &= ~mask;
 174                 else
 175                         type = mask;
 176         }
 177
 178         if (!count) {
 179                 IR_dprintk(1, "Protocol not specified\n");
 180                 return -EINVAL;
 181         }
 182
 183         if (ir_dev->props && ir_dev->props->change_protocol) {
 184                 rc = ir_dev->props->change_protocol(ir_dev->props->priv,
 185                                                     type);
 186                 if (rc < 0) {
 187                         IR_dprintk(1, "Error setting protocols to 0x%llx\n",
 188                                    (long long)type);
 189                         return -EINVAL;
 190                 }
 191         }
 192
 193         if (ir_dev->props && ir_dev->props->driver_type == RC_DRIVER_SCANCODE) {
 194                 spin_lock_irqsave(&ir_dev->rc_tab.lock, flags);
 195                 ir_dev->rc_tab.ir_type = type;
 196                 spin_unlock_irqrestore(&ir_dev->rc_tab.lock, flags);
 197         } else {
 198                 ir_dev->raw->enabled_protocols = type;
 199         }
 200
 201         IR_dprintk(1, "Current protocol(s): 0x%llx\n",
 202                    (long long)type);
 203
 204         return len;
 205 }
 206
 207 #define ADD_HOTPLUG_VAR(fmt, val...)                                    \
 208         do {                                                            \
 209                 int err = add_uevent_var(env, fmt, val);                \
 210                 if (err)                                                \
 211                         return err;                                     \
 212         } while (0)
 213
 214 static int rc_dev_uevent(struct device *device, struct kobj_uevent_env *env)
 215 {
 216         struct ir_input_dev *ir_dev = dev_get_drvdata(device);
 217
 218         if (ir_dev->rc_tab.name)
 219                 ADD_HOTPLUG_VAR("NAME=%s", ir_dev->rc_tab.name);
 220         if (ir_dev->driver_name)
 221                 ADD_HOTPLUG_VAR("DRV_NAME=%s", ir_dev->driver_name);
 222
 223         return 0;
 224 }
 225
 226 /*
 227  * Static device attribute struct with the sysfs attributes for IR's
 228  */
 229 static DEVICE_ATTR(protocols, S_IRUGO | S_IWUSR,
 230                    show_protocols, store_protocols);
 231
 232 static struct attribute *rc_dev_attrs[] = {
 233         &dev_attr_protocols.attr,
 234         NULL,
 235 };
 236
 237 static struct attribute_group rc_dev_attr_grp = {
 238         .attrs  = rc_dev_attrs,
 239 };
 240
 241 static const struct attribute_group *rc_dev_attr_groups[] = {
 242         &rc_dev_attr_grp,
 243         NULL
 244 };
 245
 246 static struct device_type rc_dev_type = {
 247         .groups         = rc_dev_attr_groups,
 248         .uevent         = rc_dev_uevent,
 249 };
 250
 251 /**
 252  * ir_register_class() - creates the sysfs for /sys/class/rc/rc?
 253  * @input_dev:  the struct input_dev descriptor of the device
 254  *
 255  * This routine is used to register the syfs code for IR class
 256  */
 257 int ir_register_class(struct input_dev *input_dev)
 258 {
 259         int rc;
 260         const char *path;
 261         struct ir_input_dev *ir_dev = input_get_drvdata(input_dev);
 262         int devno = find_first_zero_bit(&ir_core_dev_number,
 263                                         IRRCV_NUM_DEVICES);
 264
 265         if (unlikely(devno < 0))
 266                 return devno;
 267
 268         ir_dev->dev.type = &rc_dev_type;
 269
 270         ir_dev->dev.class = &ir_input_class;
 271         ir_dev->dev.parent = input_dev->dev.parent;
 272         dev_set_name(&ir_dev->dev, "rc%d", devno);
 273         dev_set_drvdata(&ir_dev->dev, ir_dev);
 274         rc = device_register(&ir_dev->dev);
 275         if (rc)
 276                 return rc;
 277
 278
 279         input_dev->dev.parent = &ir_dev->dev;
 280         rc = input_register_device(input_dev);
 281         if (rc < 0) {
 282                 device_del(&ir_dev->dev);
 283                 return rc;
 284         }
 285
 286         __module_get(THIS_MODULE);
 287
 288         path = kobject_get_path(&ir_dev->dev.kobj, GFP_KERNEL);
 289         printk(KERN_INFO "%s: %s as %s\n",
 290                 dev_name(&ir_dev->dev),
 291                 input_dev->name ? input_dev->name : "Unspecified device",
 292                 path ? path : "N/A");
 293         kfree(path);
 294
 295         ir_dev->devno = devno;
 296         set_bit(devno, &ir_core_dev_number);
 297
 298         return 0;
 299 };
 300
 301 /**
 302  * ir_unregister_class() - removes the sysfs for sysfs for
 303  *                         /sys/class/rc/rc?
 304  * @input_dev:  the struct input_dev descriptor of the device
 305  *
 306  * This routine is used to unregister the syfs code for IR class
 307  */
 308 void ir_unregister_class(struct input_dev *input_dev)
 309 {
 310         struct ir_input_dev *ir_dev = input_get_drvdata(input_dev);
 311
 312         clear_bit(ir_dev->devno, &ir_core_dev_number);
 313         input_unregister_device(input_dev);
 314         device_del(&ir_dev->dev);
 315
 316         module_put(THIS_MODULE);
 317 }
 318
 319 /*
 320  * Init/exit code for the module. Basically, creates/removes /sys/class/rc
 321  */
 322
 323 static int __init ir_core_init(void)
 324 {
 325         int rc = class_register(&ir_input_class);
 326         if (rc) {
 327                 printk(KERN_ERR "ir_core: unable to register rc class\n");
 328                 return rc;
 329         }
 330
 331         /* Initialize/load the decoders/keymap code that will be used */
 332         ir_raw_init();
 333         ir_rcmap_init();
 334
 335         return 0;
 336 }
 337
 338 static void __exit ir_core_exit(void)
 339 {
 340         class_unregister(&ir_input_class);
 341         ir_rcmap_cleanup();
 342 }
 343
 344 module_init(ir_core_init);
 345 module_exit(ir_core_exit);