diff options
author | MyungJoo Ham <myungjoo.ham@samsung.com> | 2012-04-20 14:16:26 +0900 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2012-04-20 09:24:03 -0700 |
commit | bde68e60b18208978c50c6fb9bdf29826d2887f3 (patch) | |
tree | 62b48807d48c2454c374bede680c9e9c6cf71a0d /include/linux/extcon.h | |
parent | 806d9dd71ff52ef09764585baaeec23afbb98560 (diff) |
Extcon: support mutually exclusive relation between cables.
There could be cables that t recannot be attaches simulatenously. Extcon
device drivers may express such information via mutually_exclusive in
struct extcon_dev.
For example, for an extcon device with 16 cables (bits 0 to 15 are
available), if mutually_exclusive = { 0x7, 0xC0, 0x81, 0 }, then, the
following attachments are prohibitted.
{0, 1}
{0, 2}
{1, 2}
{6, 7}
{0, 7}
and every attachment set that are superset of one of the above.
For the detail, please refer to linux/include/linux/extcon.h.
The concept is suggested by NeilBrown <neilb@suse.de>
Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
--
Changes from V5:
- Updated sysfs format
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'include/linux/extcon.h')
-rw-r--r-- | include/linux/extcon.h | 28 |
1 files changed, 23 insertions, 5 deletions
diff --git a/include/linux/extcon.h b/include/linux/extcon.h index 20e24b32a17..6495f773140 100644 --- a/include/linux/extcon.h +++ b/include/linux/extcon.h @@ -78,6 +78,14 @@ struct extcon_cable; * @supported_cable Array of supported cable name ending with NULL. * If supported_cable is NULL, cable name related APIs * are disabled. + * @mutually_exclusive Array of mutually exclusive set of cables that cannot + * be attached simultaneously. The array should be + * ending with NULL or be NULL (no mutually exclusive + * cables). For example, if it is { 0x7, 0x30, 0}, then, + * {0, 1}, {0, 1, 2}, {0, 2}, {1, 2}, or {4, 5} cannot + * be attached simulataneously. {0x7, 0} is equivalent to + * {0x3, 0x6, 0x5, 0}. If it is {0xFFFFFFFF, 0}, there + * can be no simultaneous connections. * @print_name An optional callback to override the method to print the * name of the extcon device. * @print_state An optional callback to override the method to print the @@ -103,6 +111,7 @@ struct extcon_dev { /* --- Optional user initializing data --- */ const char *name; const char **supported_cable; + const u32 *mutually_exclusive; /* --- Optional callbacks to override class functions --- */ ssize_t (*print_name)(struct extcon_dev *edev, char *buf); @@ -119,6 +128,10 @@ struct extcon_dev { /* /sys/class/extcon/.../cable.n/... */ struct device_type extcon_dev_type; struct extcon_cable *cables; + /* /sys/class/extcon/.../mutually_exclusive/... */ + struct attribute_group attr_g_muex; + struct attribute **attrs_muex; + struct device_attribute *d_attrs_muex; }; /** @@ -179,8 +192,8 @@ static inline u32 extcon_get_state(struct extcon_dev *edev) return edev->state; } -extern void extcon_set_state(struct extcon_dev *edev, u32 state); -extern void extcon_update_state(struct extcon_dev *edev, u32 mask, u32 state); +extern int extcon_set_state(struct extcon_dev *edev, u32 state); +extern int extcon_update_state(struct extcon_dev *edev, u32 mask, u32 state); /* * get/set_cable_state access each bit of the 32b encoded state value. @@ -235,11 +248,16 @@ static inline u32 extcon_get_state(struct extcon_dev *edev) return 0; } -static inline void extcon_set_state(struct extcon_dev *edev, u32 state) { } +static inline int extcon_set_state(struct extcon_dev *edev, u32 state) +{ + return 0; +} -static inline void extcon_update_state(struct extcon_dev *edev, u32 mask, +static inline int extcon_update_state(struct extcon_dev *edev, u32 mask, u32 state) -{ } +{ + return 0; +} static inline int extcon_find_cable_index(struct extcon_dev *edev, const char *cable_name) |