include/linux/extcon.h

   1 /*
   2  *  External connector (extcon) class driver
   3  *
   4  * Copyright (C) 2015 Samsung Electronics
   5  * Author: Chanwoo Choi <cw00.choi@samsung.com>
   6  *
   7  * Copyright (C) 2012 Samsung Electronics
   8  * Author: Donggeun Kim <dg77.kim@samsung.com>
   9  * Author: MyungJoo Ham <myungjoo.ham@samsung.com>
  10  *
  11  * based on switch class driver
  12  * Copyright (C) 2008 Google, Inc.
  13  * Author: Mike Lockwood <lockwood@android.com>
  14  *
  15  * This software is licensed under the terms of the GNU General Public
  16  * License version 2, as published by the Free Software Foundation, and
  17  * may be copied, distributed, and modified under those terms.
  18  *
  19  * This program is distributed in the hope that it will be useful,
  20  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  21  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  22  * GNU General Public License for more details.
  23  *
  24 */
  25
  26 #ifndef __LINUX_EXTCON_H__
  27 #define __LINUX_EXTCON_H__
  28
  29 #include <linux/device.h>
  30 #include <linux/notifier.h>
  31 #include <linux/sysfs.h>
  32
  33 /*
  34  * Define the unique id of supported external connectors
  35  */
  36 #define EXTCON_NONE                     0
  37
  38 #define EXTCON_USB                      1       /* USB connector */
  39 #define EXTCON_USB_HOST                 2
  40
  41 #define EXTCON_TA                       3       /* Charger connector */
  42 #define EXTCON_FAST_CHARGER             4
  43 #define EXTCON_SLOW_CHARGER             5
  44 #define EXTCON_CHARGE_DOWNSTREAM        6
  45
  46 #define EXTCON_LINE_IN                  7       /* Audio/Video connector */
  47 #define EXTCON_LINE_OUT                 8
  48 #define EXTCON_MICROPHONE               9
  49 #define EXTCON_HEADPHONE                10
  50 #define EXTCON_HDMI                     11
  51 #define EXTCON_MHL                      12
  52 #define EXTCON_DVI                      13
  53 #define EXTCON_VGA                      14
  54 #define EXTCON_SPDIF_IN                 15
  55 #define EXTCON_SPDIF_OUT                16
  56 #define EXTCON_VIDEO_IN                 17
  57 #define EXTCON_VIDEO_OUT                18
  58
  59 #define EXTCON_DOCK                     19      /* Misc connector */
  60 #define EXTCON_JIG                      20
  61 #define EXTCON_MECHANICAL               21
  62
  63 struct extcon_cable;
  64
  65 /**
  66  * struct extcon_dev - An extcon device represents one external connector.
  67  * @name:               The name of this extcon device. Parent device name is
  68  *                      used if NULL.
  69  * @supported_cable:    Array of supported cable names ending with EXTCON_NONE.
  70  *                      If supported_cable is NULL, cable name related APIs
  71  *                      are disabled.
  72  * @mutually_exclusive: Array of mutually exclusive set of cables that cannot
  73  *                      be attached simultaneously. The array should be
  74  *                      ending with NULL or be NULL (no mutually exclusive
  75  *                      cables). For example, if it is { 0x7, 0x30, 0}, then,
  76  *                      {0, 1}, {0, 1, 2}, {0, 2}, {1, 2}, or {4, 5} cannot
  77  *                      be attached simulataneously. {0x7, 0} is equivalent to
  78  *                      {0x3, 0x6, 0x5, 0}. If it is {0xFFFFFFFF, 0}, there
  79  *                      can be no simultaneous connections.
  80  * @print_state:        An optional callback to override the method to print the
  81  *                      status of the extcon device.
  82  * @dev:                Device of this extcon.
  83  * @state:              Attach/detach state of this extcon. Do not provide at
  84  *                      register-time.
  85  * @nh:                 Notifier for the state change events from this extcon
  86  * @entry:              To support list of extcon devices so that users can
  87  *                      search for extcon devices based on the extcon name.
  88  * @lock:
  89  * @max_supported:      Internal value to store the number of cables.
  90  * @extcon_dev_type:    Device_type struct to provide attribute_groups
  91  *                      customized for each extcon device.
  92  * @cables:             Sysfs subdirectories. Each represents one cable.
  93  *
  94  * In most cases, users only need to provide "User initializing data" of
  95  * this struct when registering an extcon. In some exceptional cases,
  96  * optional callbacks may be needed. However, the values in "internal data"
  97  * are overwritten by register function.
  98  */
  99 struct extcon_dev {
 100         /* Optional user initializing data */
 101         const char *name;
 102         const unsigned int *supported_cable;
 103         const u32 *mutually_exclusive;
 104
 105         /* Optional callbacks to override class functions */
 106         ssize_t (*print_state)(struct extcon_dev *edev, char *buf);
 107
 108         /* Internal data. Please do not set. */
 109         struct device dev;
 110         struct raw_notifier_head *nh;
 111         struct list_head entry;
 112         int max_supported;
 113         spinlock_t lock;        /* could be called by irq handler */
 114         u32 state;
 115
 116         /* /sys/class/extcon/.../cable.n/... */
 117         struct device_type extcon_dev_type;
 118         struct extcon_cable *cables;
 119
 120         /* /sys/class/extcon/.../mutually_exclusive/... */
 121         struct attribute_group attr_g_muex;
 122         struct attribute **attrs_muex;
 123         struct device_attribute *d_attrs_muex;
 124 };
 125
 126 /**
 127  * struct extcon_cable - An internal data for each cable of extcon device.
 128  * @edev:               The extcon device
 129  * @cable_index:        Index of this cable in the edev
 130  * @attr_g:             Attribute group for the cable
 131  * @attr_name:          "name" sysfs entry
 132  * @attr_state:         "state" sysfs entry
 133  * @attrs:              Array pointing to attr_name and attr_state for attr_g
 134  */
 135 struct extcon_cable {
 136         struct extcon_dev *edev;
 137         int cable_index;
 138
 139         struct attribute_group attr_g;
 140         struct device_attribute attr_name;
 141         struct device_attribute attr_state;
 142
 143         struct attribute *attrs[3]; /* to be fed to attr_g.attrs */
 144 };
 145
 146 /**
 147  * struct extcon_specific_cable_nb - An internal data for
 148  *                                   extcon_register_interest().
 149  * @user_nb:            user provided notifier block for events from
 150  *                      a specific cable.
 151  * @cable_index:        the target cable.
 152  * @edev:               the target extcon device.
 153  * @previous_value:     the saved previous event value.
 154  */
 155 struct extcon_specific_cable_nb {
 156         struct notifier_block *user_nb;
 157         int cable_index;
 158         struct extcon_dev *edev;
 159         unsigned long previous_value;
 160 };
 161
 162 #if IS_ENABLED(CONFIG_EXTCON)
 163
 164 /*
 165  * Following APIs are for notifiers or configurations.
 166  * Notifiers are the external port and connection devices.
 167  */
 168 extern int extcon_dev_register(struct extcon_dev *edev);
 169 extern void extcon_dev_unregister(struct extcon_dev *edev);
 170 extern int devm_extcon_dev_register(struct device *dev,
 171                                     struct extcon_dev *edev);
 172 extern void devm_extcon_dev_unregister(struct device *dev,
 173                                        struct extcon_dev *edev);
 174 extern struct extcon_dev *extcon_get_extcon_dev(const char *extcon_name);
 175
 176 /*
 177  * Following APIs control the memory of extcon device.
 178  */
 179 extern struct extcon_dev *extcon_dev_allocate(const unsigned int *cable);
 180 extern void extcon_dev_free(struct extcon_dev *edev);
 181 extern struct extcon_dev *devm_extcon_dev_allocate(struct device *dev,
 182                                                    const unsigned int *cable);
 183 extern void devm_extcon_dev_free(struct device *dev, struct extcon_dev *edev);
 184
 185 /*
 186  * get/set/update_state access the 32b encoded state value, which represents
 187  * states of all possible cables of the multistate port. For example, if one
 188  * calls extcon_set_state(edev, 0x7), it may mean that all the three cables
 189  * are attached to the port.
 190  */
 191 static inline u32 extcon_get_state(struct extcon_dev *edev)
 192 {
 193         return edev->state;
 194 }
 195
 196 extern int extcon_set_state(struct extcon_dev *edev, u32 state);
 197 extern int extcon_update_state(struct extcon_dev *edev, u32 mask, u32 state);
 198
 199 /*
 200  * get/set_cable_state access each bit of the 32b encoded state value.
 201  * They are used to access the status of each cable based on the cable_name.
 202  */
 203 extern int extcon_get_cable_state_(struct extcon_dev *edev, unsigned int id);
 204 extern int extcon_set_cable_state_(struct extcon_dev *edev, unsigned int id,
 205                                    bool cable_state);
 206
 207 extern int extcon_get_cable_state(struct extcon_dev *edev,
 208                                   const char *cable_name);
 209 extern int extcon_set_cable_state(struct extcon_dev *edev,
 210                                   const char *cable_name, bool cable_state);
 211
 212 /*
 213  * Following APIs are for notifiees (those who want to be notified)
 214  * to register a callback for events from a specific cable of the extcon.
 215  * Notifiees are the connected device drivers wanting to get notified by
 216  * a specific external port of a connection device.
 217  */
 218 extern int extcon_register_interest(struct extcon_specific_cable_nb *obj,
 219                                     const char *extcon_name,
 220                                     const char *cable_name,
 221                                     struct notifier_block *nb);
 222 extern int extcon_unregister_interest(struct extcon_specific_cable_nb *nb);
 223
 224 /*
 225  * Following APIs are to monitor every action of a notifier.
 226  * Registrar gets notified for every external port of a connection device.
 227  * Probably this could be used to debug an action of notifier; however,
 228  * we do not recommend to use this for normal 'notifiee' device drivers who
 229  * want to be notified by a specific external port of the notifier.
 230  */
 231 extern int extcon_register_notifier(struct extcon_dev *edev, unsigned int id,
 232                                     struct notifier_block *nb);
 233 extern int extcon_unregister_notifier(struct extcon_dev *edev, unsigned int id,
 234                                     struct notifier_block *nb);
 235
 236 /*
 237  * Following API get the extcon device from devicetree.
 238  * This function use phandle of devicetree to get extcon device directly.
 239  */
 240 extern struct extcon_dev *extcon_get_edev_by_phandle(struct device *dev,
 241                                                      int index);
 242
 243 /* Following API to get information of extcon device */
 244 extern const char *extcon_get_edev_name(struct extcon_dev *edev);
 245
 246 #else /* CONFIG_EXTCON */
 247 static inline int extcon_dev_register(struct extcon_dev *edev)
 248 {
 249         return 0;
 250 }
 251
 252 static inline void extcon_dev_unregister(struct extcon_dev *edev) { }
 253
 254 static inline int devm_extcon_dev_register(struct device *dev,
 255                                            struct extcon_dev *edev)
 256 {
 257         return -EINVAL;
 258 }
 259
 260 static inline void devm_extcon_dev_unregister(struct device *dev,
 261                                               struct extcon_dev *edev) { }
 262
 263 static inline struct extcon_dev *extcon_dev_allocate(const unsigned int *cable)
 264 {
 265         return ERR_PTR(-ENOSYS);
 266 }
 267
 268 static inline void extcon_dev_free(struct extcon_dev *edev) { }
 269
 270 static inline struct extcon_dev *devm_extcon_dev_allocate(struct device *dev,
 271                                                 const unsigned int *cable)
 272 {
 273         return ERR_PTR(-ENOSYS);
 274 }
 275
 276 static inline void devm_extcon_dev_free(struct extcon_dev *edev) { }
 277
 278 static inline u32 extcon_get_state(struct extcon_dev *edev)
 279 {
 280         return 0;
 281 }
 282
 283 static inline int extcon_set_state(struct extcon_dev *edev, u32 state)
 284 {
 285         return 0;
 286 }
 287
 288 static inline int extcon_update_state(struct extcon_dev *edev, u32 mask,
 289                                        u32 state)
 290 {
 291         return 0;
 292 }
 293
 294 static inline int extcon_get_cable_state_(struct extcon_dev *edev,
 295                                           unsigned int id)
 296 {
 297         return 0;
 298 }
 299
 300 static inline int extcon_set_cable_state_(struct extcon_dev *edev,
 301                                           unsigned int id, bool cable_state)
 302 {
 303         return 0;
 304 }
 305
 306 static inline int extcon_get_cable_state(struct extcon_dev *edev,
 307                         const char *cable_name)
 308 {
 309         return 0;
 310 }
 311
 312 static inline int extcon_set_cable_state(struct extcon_dev *edev,
 313                         const char *cable_name, int state)
 314 {
 315         return 0;
 316 }
 317
 318 static inline struct extcon_dev *extcon_get_extcon_dev(const char *extcon_name)
 319 {
 320         return NULL;
 321 }
 322
 323 static inline int extcon_register_notifier(struct extcon_dev *edev,
 324                                         unsigned int id,
 325                                         struct notifier_block *nb)
 326 {
 327         return 0;
 328 }
 329
 330 static inline int extcon_unregister_notifier(struct extcon_dev *edev,
 331                                         unsigned int id,
 332                                         struct notifier_block *nb)
 333 {
 334         return 0;
 335 }
 336
 337 static inline int extcon_register_interest(struct extcon_specific_cable_nb *obj,
 338                                            const char *extcon_name,
 339                                            const char *cable_name,
 340                                            struct notifier_block *nb)
 341 {
 342         return 0;
 343 }
 344
 345 static inline int extcon_unregister_interest(struct extcon_specific_cable_nb
 346                                                     *obj)
 347 {
 348         return 0;
 349 }
 350
 351 static inline struct extcon_dev *extcon_get_edev_by_phandle(struct device *dev,
 352                                                             int index)
 353 {
 354         return ERR_PTR(-ENODEV);
 355 }
 356 #endif /* CONFIG_EXTCON */
 357 #endif /* __LINUX_EXTCON_H__ */