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