new file mode 100644
@@ -0,0 +1,112 @@
+Extcon - external connector
+===========================
+
+Extcon is generic framework used for notifying client drivers
+about specific cable connections and disconnections.
+
+Provider API
+============
+
+Providers API consists of very few functions:
+
+extcon_dev_register() - register new extcon provider
+extcon_dev_unregister() - unregister extcon provider
+
+extcon_get_cable_state_() - get specific cable state
+extcon_set_cable_state_() - set specific cable state
+
+extcon_update_state() - update entire extcon state
+extcon_set_state() - set entire extcon state
+
+There are few fields in struct extcon_dev to be filled before passing it
+to extcon_dev_register() functions:
+
+name - name of extcon controller
+node - devicetree node of parent device
+supported_cable - array of strings with cable names ended with NULL pointer
+
+Example of cable array definition example can be found below:
+
+ enum extcon_cable_name {
+ EXTCON_USB = 0,
+ EXTCON_USB_HOST,
+ EXTCON_TA,
+ EXTCON_FAST_CHARGER,
+ EXTCON_SLOW_CHARGER,
+ EXTCON_CHARGE_DOWNSTREAM,
+ EXTCON_HDMI,
+ EXTCON_MHL,
+ EXTCON_DVI,
+ EXTCON_VGA,
+ EXTCON_DOCK,
+ EXTCON_LINE_IN,
+ EXTCON_LINE_OUT,
+ EXTCON_MIC_IN,
+ EXTCON_HEADPHONE_OUT,
+ EXTCON_SPDIF_IN,
+ EXTCON_SPDIF_OUT,
+ EXTCON_VIDEO_IN,
+ EXTCON_VIDEO_OUT,
+ EXTCON_MECHANICAL,
+ };
+
+ const char *extcon_cable_name[] = {
+ [EXTCON_USB] = "USB",
+ [EXTCON_USB_HOST] = "USB-Host",
+ [EXTCON_TA] = "TA",
+ [EXTCON_FAST_CHARGER] = "Fast-charger",
+ [EXTCON_SLOW_CHARGER] = "Slow-charger",
+ [EXTCON_CHARGE_DOWNSTREAM] = "Charge-downstream",
+ [EXTCON_HDMI] = "HDMI",
+ [EXTCON_MHL] = "MHL",
+ [EXTCON_DVI] = "DVI",
+ [EXTCON_VGA] = "VGA",
+ [EXTCON_DOCK] = "Dock",
+ [EXTCON_LINE_IN] = "Line-in",
+ [EXTCON_LINE_OUT] = "Line-out",
+ [EXTCON_MIC_IN] = "Microphone",
+ [EXTCON_HEADPHONE_OUT] = "Headphone",
+ [EXTCON_SPDIF_IN] = "SPDIF-in",
+ [EXTCON_SPDIF_OUT] = "SPDIF-out",
+ [EXTCON_VIDEO_IN] = "Video-in",
+ [EXTCON_VIDEO_OUT] = "Video-out",
+ [EXTCON_MECHANICAL] = "Mechanical",
+ };
+
+Cable name strings are used for debug messages and sysfs.
+
+After extcon device registration you can use functions modifying extcon state.
+If any extcon clients will register their interests in some cables, they will
+recieve notifications about cable state changes.
+
+Client API
+==========
+
+Extcon client API is also pretty simple. It consists of funtions:
+
+of_extcon_get_cable_by_index() - returns extcon_cable at selected index
+of_extcon_get_cable() - returns extcon_cable associated with
+ selected name
+extcon_get_cable() - the same as above, but takes struct device
+ instead of struct device_node
+extcon_det_cable_by_name() - return specified cable form extcon device
+ found by name. It's for use in drivers without
+ devicetree support, and shouldn't be used in
+ new drivers.
+
+extcon_register_interest() - register interest in selected cable
+extcon_unregister_interest() - unregister cable interest
+
+extcon_get_cable_state() - get state of given cable
+
+The extcon_register_interest() function takes three parameters,
+struct extcon_cable, struct extcon_cable_nb and extcon_notifier_fn_t
+which is pointer to callback function called when cable state changes.
+
+There are also two functions:
+
+extcon_register_notifier() - register notifier for entire extcon state
+extcon_unregister_notifier() - unregister such notifier
+
+But they should be used only for debug, and use of them in client drivers
+is not recommended.
@@ -33,38 +33,6 @@
#include <linux/sysfs.h>
#include <linux/of.h>
-/*
- * extcon_cable_name suggests the standard cable names for commonly used
- * cable types.
- *
- * However, please do not use extcon_cable_name directly for extcon_dev
- * struct's supported_cable pointer unless your device really supports
- * every single port-type of the following cable names. Please choose cable
- * names that are actually used in your extcon device.
- */
-const char extcon_cable_name[][CABLE_NAME_MAX + 1] = {
- [EXTCON_USB] = "USB",
- [EXTCON_USB_HOST] = "USB-Host",
- [EXTCON_TA] = "TA",
- [EXTCON_FAST_CHARGER] = "Fast-charger",
- [EXTCON_SLOW_CHARGER] = "Slow-charger",
- [EXTCON_CHARGE_DOWNSTREAM] = "Charge-downstream",
- [EXTCON_HDMI] = "HDMI",
- [EXTCON_MHL] = "MHL",
- [EXTCON_DVI] = "DVI",
- [EXTCON_VGA] = "VGA",
- [EXTCON_DOCK] = "Dock",
- [EXTCON_LINE_IN] = "Line-in",
- [EXTCON_LINE_OUT] = "Line-out",
- [EXTCON_MIC_IN] = "Microphone",
- [EXTCON_HEADPHONE_OUT] = "Headphone",
- [EXTCON_SPDIF_IN] = "SPDIF-in",
- [EXTCON_SPDIF_OUT] = "SPDIF-out",
- [EXTCON_VIDEO_IN] = "Video-in",
- [EXTCON_VIDEO_OUT] = "Video-out",
- [EXTCON_MECHANICAL] = "Mechanical",
-};
-
static struct class *extcon_class;
#if defined(CONFIG_ANDROID)
static struct class_compat *switch_class;
@@ -31,48 +31,6 @@
#define SUPPORTED_CABLE_MAX 32
#define CABLE_NAME_MAX 30
-/*
- * The standard cable name is to help support general notifier
- * and notifiee device drivers to share the common names.
- * Please use standard cable names unless your notifier device has
- * a very unique and abnormal cable or
- * the cable type is supposed to be used with only one unique
- * pair of notifier/notifiee devices.
- *
- * Please add any other "standard" cables used with extcon dev.
- *
- * You may add a dot and number to specify version or specification
- * of the specific cable if it is required. (e.g., "Fast-charger.18"
- * and "Fast-charger.10" for 1.8A and 1.0A chargers)
- * However, the notifiee and notifier should be able to handle such
- * string and if the notifiee can negotiate the protocol or identify,
- * you don't need such convention. This convention is helpful when
- * notifier can distinguish but notifiee cannot.
- */
-enum extcon_cable_name {
- EXTCON_USB = 0,
- EXTCON_USB_HOST,
- EXTCON_TA, /* Travel Adaptor */
- EXTCON_FAST_CHARGER,
- EXTCON_SLOW_CHARGER,
- EXTCON_CHARGE_DOWNSTREAM, /* Charging an external device */
- EXTCON_HDMI,
- EXTCON_MHL,
- EXTCON_DVI,
- EXTCON_VGA,
- EXTCON_DOCK,
- EXTCON_LINE_IN,
- EXTCON_LINE_OUT,
- EXTCON_MIC_IN,
- EXTCON_HEADPHONE_OUT,
- EXTCON_SPDIF_IN,
- EXTCON_SPDIF_OUT,
- EXTCON_VIDEO_IN,
- EXTCON_VIDEO_OUT,
- EXTCON_MECHANICAL,
-};
-extern const char extcon_cable_name[][CABLE_NAME_MAX + 1];
-
struct extcon_cable;
/**
This patch removes cable array example form extcon code, to avoid littering driver namespace. Now it's located in extcon documentation. Signed-off-by: Robert Baldyga <r.baldyga@samsung.com> --- Documentation/extcon/extcon.txt | 112 +++++++++++++++++++++++++++++++++++++++ drivers/extcon/extcon-class.c | 32 ----------- include/linux/extcon.h | 42 --------------- 3 files changed, 112 insertions(+), 74 deletions(-) create mode 100644 Documentation/extcon/extcon.txt