Document the keyboard notifier.
Signed-off-by: Samuel Thibault <[email protected]>
--- /dev/null 2008-02-09 01:22:34.790011677 +0000
+++ linux/Documentation/input/notifier.txt 2008-02-09 01:28:12.000000000 +0000
@@ -0,0 +1,52 @@
+Keyboard notifier
+
+One can use register_keyboard_notifier to get called back on keyboard
+events (see kbd_keycode() function for details). The passed structure is
+keyboard_notifier_param:
+
+- 'vc' always provide the VC for which the keyboard event applies?;
+- 'down' is 1 for a key press event, 0 for a key release?;
+- 'shift' is the current modifier state, mask bit indexes are KG_*?;
+- 'value' depends on the type of event.
+
+- KBD_KEYCODE events are always sent before other events, value is the keycode.
+- KBD_UNBOUND_KEYCODE events are sent if the keycode is not bound to a keysym.
+ value is the keycode.
+- KBD_UNICODE events are sent if the keycode -> keysym translation produced a
+ unicode character. value is the unicode value.
+- KBD_KEYSYM events are sent if the keycode -> keysym translation produced a
+ non-unicode character. value is the keysym.
+- KBD_POST_KEYSYM events are sent after the treatment of non-unicode keysyms.
+ That permits to inspect the resulting LEDs for instance.
+
+For each kind of event but the last, the callback may return NOTIFY_STOP in
+order to "eat" the event: the notify loop is stopped and the keyboard event is
+dropped.
+
+I a rough C snippet, we have:
+
+kbd_keycode(keycode) {
+ ...
+ params.value = keycode;
+ if (notifier_call_chain(KBD_KEYCODE,¶ms) == NOTIFY_STOP)
+ || !bound) {
+ notifier_call_chain(KBD_UNBOUND_KEYCODE,¶ms);
+ return;
+ }
+
+ if (unicode) {
+ param.value = unicode;
+ if (notifier_call_chain(KBD_UNICODE,¶ms) == NOTIFY_STOP)
+ return;
+ emit unicode;
+ return;
+ }
+
+ params.value = keysym;
+ if (notifier_call_chain(KBD_KEYSYM,¶ms) == NOTIFY_STOP)
+ return;
+ apply keysym;
+ notifier_call_chain(KBD_POST_KEYSYM,¶ms);
+}
+
+NOTE: This notifier is usually called from interrupt context.
On Sat, 9 Feb 2008 01:33:22 +0000 Samuel Thibault wrote:
> Document the keyboard notifier.
>
> Signed-off-by: Samuel Thibault <[email protected]>
>
> --- /dev/null 2008-02-09 01:22:34.790011677 +0000
> +++ linux/Documentation/input/notifier.txt 2008-02-09 01:28:12.000000000 +0000
> @@ -0,0 +1,52 @@
> +Keyboard notifier
> +
> +One can use register_keyboard_notifier to get called back on keyboard
> +events (see kbd_keycode() function for details). The passed structure is
> +keyboard_notifier_param:
> +
> +- 'vc' always provide the VC for which the keyboard event applies?;
> +- 'down' is 1 for a key press event, 0 for a key release?;
> +- 'shift' is the current modifier state, mask bit indexes are KG_*?;
No space before the ';' (3 times).
> +- 'value' depends on the type of event.
> +
> +- KBD_KEYCODE events are always sent before other events, value is the keycode.
> +- KBD_UNBOUND_KEYCODE events are sent if the keycode is not bound to a keysym.
> + value is the keycode.
> +- KBD_UNICODE events are sent if the keycode -> keysym translation produced a
> + unicode character. value is the unicode value.
> +- KBD_KEYSYM events are sent if the keycode -> keysym translation produced a
> + non-unicode character. value is the keysym.
> +- KBD_POST_KEYSYM events are sent after the treatment of non-unicode keysyms.
> + That permits to inspect the resulting LEDs for instance.
That permits (some object word here, like: you, one, code, etc.) to
inspect ...
> +
> +For each kind of event but the last, the callback may return NOTIFY_STOP in
> +order to "eat" the event: the notify loop is stopped and the keyboard event is
> +dropped.
> +
> +I a rough C snippet, we have:
In a rough (?)
> +
> +kbd_keycode(keycode) {
> + ...
> + params.value = keycode;
> + if (notifier_call_chain(KBD_KEYCODE,¶ms) == NOTIFY_STOP)
> + || !bound) {
> + notifier_call_chain(KBD_UNBOUND_KEYCODE,¶ms);
> + return;
> + }
> +
> + if (unicode) {
> + param.value = unicode;
> + if (notifier_call_chain(KBD_UNICODE,¶ms) == NOTIFY_STOP)
> + return;
> + emit unicode;
> + return;
> + }
> +
> + params.value = keysym;
> + if (notifier_call_chain(KBD_KEYSYM,¶ms) == NOTIFY_STOP)
> + return;
> + apply keysym;
> + notifier_call_chain(KBD_POST_KEYSYM,¶ms);
> +}
> +
> +NOTE: This notifier is usually called from interrupt context.
> --
---
~Randy
Randy Dunlap, le Fri 08 Feb 2008 20:12:53 -0800, a ?crit :
> On Sat, 9 Feb 2008 01:33:22 +0000 Samuel Thibault wrote:
> > +- 'vc' always provide the VC for which the keyboard event applies?;
> > +- 'down' is 1 for a key press event, 0 for a key release?;
> > +- 'shift' is the current modifier state, mask bit indexes are KG_*?;
>
> No space before the ';' (3 times).
Well, as expected in French... I'll fix that.
> > +For each kind of event but the last, the callback may return NOTIFY_STOP in
> > +order to "eat" the event: the notify loop is stopped and the keyboard event is
> > +dropped.
> > +
> > +I a rough C snippet, we have:
>
> In a rough (?)
Yes, rough as "something that a C compiler will never accept, but that
you, human, will make sense out of it".
Samuel
Document the keyboard notifier.
Signed-off-by: Samuel Thibault <[email protected]>
--- /dev/null 2008-02-09 01:22:34.790011677 +0000
+++ linux/Documentation/input/notifier.txt 2008-02-09 01:28:12.000000000 +0000
@@ -0,0 +1,52 @@
+Keyboard notifier
+
+One can use register_keyboard_notifier to get called back on keyboard
+events (see kbd_keycode() function for details). The passed structure is
+keyboard_notifier_param:
+
+- 'vc' always provide the VC for which the keyboard event applies;
+- 'down' is 1 for a key press event, 0 for a key release;
+- 'shift' is the current modifier state, mask bit indexes are KG_*;
+- 'value' depends on the type of event.
+
+- KBD_KEYCODE events are always sent before other events, value is the keycode.
+- KBD_UNBOUND_KEYCODE events are sent if the keycode is not bound to a keysym.
+ value is the keycode.
+- KBD_UNICODE events are sent if the keycode -> keysym translation produced a
+ unicode character. value is the unicode value.
+- KBD_KEYSYM events are sent if the keycode -> keysym translation produced a
+ non-unicode character. value is the keysym.
+- KBD_POST_KEYSYM events are sent after the treatment of non-unicode keysyms.
+ That permits one to inspect the resulting LEDs for instance.
+
+For each kind of event but the last, the callback may return NOTIFY_STOP in
+order to "eat" the event: the notify loop is stopped and the keyboard event is
+dropped.
+
+In a rough C snippet, we have:
+
+kbd_keycode(keycode) {
+ ...
+ params.value = keycode;
+ if (notifier_call_chain(KBD_KEYCODE,¶ms) == NOTIFY_STOP)
+ || !bound) {
+ notifier_call_chain(KBD_UNBOUND_KEYCODE,¶ms);
+ return;
+ }
+
+ if (unicode) {
+ param.value = unicode;
+ if (notifier_call_chain(KBD_UNICODE,¶ms) == NOTIFY_STOP)
+ return;
+ emit unicode;
+ return;
+ }
+
+ params.value = keysym;
+ if (notifier_call_chain(KBD_KEYSYM,¶ms) == NOTIFY_STOP)
+ return;
+ apply keysym;
+ notifier_call_chain(KBD_POST_KEYSYM,¶ms);
+}
+
+NOTE: This notifier is usually called from interrupt context.
Samuel Thibault wrote:
> Randy Dunlap, le Fri 08 Feb 2008 20:12:53 -0800, a ?crit :
>> On Sat, 9 Feb 2008 01:33:22 +0000 Samuel Thibault wrote:
>>> +- 'vc' always provide the VC for which the keyboard event applies ;
>>> +- 'down' is 1 for a key press event, 0 for a key release ;
>>> +- 'shift' is the current modifier state, mask bit indexes are KG_* ;
>> No space before the ';' (3 times).
>
> Well, as expected in French... I'll fix that.
>
>>> +For each kind of event but the last, the callback may return NOTIFY_STOP in
>>> +order to "eat" the event: the notify loop is stopped and the keyboard event is
>>> +dropped.
>>> +
>>> +I a rough C snippet, we have:
>> In a rough (?)
>
> Yes, rough as "something that a C compiler will never accept, but that
> you, human, will make sense out of it".
so s/I/In/ please.
--
~Randy
Randy Dunlap, le Sat 09 Feb 2008 07:38:59 -0800, a ?crit :
> Samuel Thibault wrote:
> >Randy Dunlap, le Fri 08 Feb 2008 20:12:53 -0800, a ?crit :
> >>On Sat, 9 Feb 2008 01:33:22 +0000 Samuel Thibault wrote:
> >>>+- 'vc' always provide the VC for which the keyboard event applies ;
> >>>+- 'down' is 1 for a key press event, 0 for a key release ;
> >>>+- 'shift' is the current modifier state, mask bit indexes are KG_* ;
> >>No space before the ';' (3 times).
> >
> >Well, as expected in French... I'll fix that.
> >
> >>>+For each kind of event but the last, the callback may return
> >>>NOTIFY_STOP in
> >>>+order to "eat" the event: the notify loop is stopped and the keyboard
> >>>event is
> >>>+dropped.
> >>>+
> >>>+I a rough C snippet, we have:
> >> In a rough (?)
> >
> >Yes, rough as "something that a C compiler will never accept, but that
> >you, human, will make sense out of it".
>
> so s/I/In/ please.
Ah oops, sorry misunderstood what you raised, I actually had fixed it in
the second version.
Thanks,
Samuel