[PATCHv6 1/2] INPUT: Introduce generic trigger/LED pairs between keyboard modifiers and input LEDs
Samuel Thibault
samuel.thibault at ens-lyon.org
Fri Jan 23 04:27:42 PST 2015
This permits to change which modifier triggers which keyboard LEDs, by adding
modifier triggers, and a series of LEDs for the VT.
This permits to fix #7063 from userland by using a modifier to implement proper
CapsLock behavior and have the keyboard caps lock led show that modifier state.
[ebroder at mokafive.com: Rebased to 3.2-rc1 or so, cleaned up some includes, and fixed some constants]
[akpm at linux-foundation.org: remove unneeded `extern', fix comment layout]
Signed-off-by: Samuel Thibault <samuel.thibault at ens-lyon.org>
Signed-off-by: Evan Broder <evan at ebroder.net>
Acked-by: Peter Korsgaard <jacmet at sunsite.dk>
Signed-off-by: John Crispin <blogic at openwrt.org>
Signed-off-by: Andrew Morton <akpm at linux-foundation.org>
---
Nothing changed in this version compared to v5.
--- a/drivers/tty/Kconfig
+++ b/drivers/tty/Kconfig
@@ -13,6 +13,9 @@ config VT
bool "Virtual terminal" if EXPERT
depends on !S390 && !UML
select INPUT
+ select NEW_LEDS
+ select LEDS_CLASS
+ select LEDS_TRIGGERS
default y
---help---
If you say Y here, you will get support for terminal devices with
--- a/drivers/tty/vt/keyboard.c
+++ b/drivers/tty/vt/keyboard.c
@@ -33,6 +33,7 @@
#include <linux/string.h>
#include <linux/init.h>
#include <linux/slab.h>
+#include <linux/leds.h>
#include <linux/kbd_kern.h>
#include <linux/kbd_diacr.h>
@@ -130,6 +131,7 @@ static char rep; /* flag telling cha
static int shift_state = 0;
static unsigned char ledstate = 0xff; /* undefined */
+static unsigned char lockstate = 0xff; /* undefined */
static unsigned char ledioctl;
/*
@@ -962,6 +964,146 @@ static void k_brl(struct vc_data *vc, un
}
/*
+ * Keyboard LEDs are propagated by default like the following example:
+ *
+ * VT keyboard LED state or modifier state, calls kbd_bh()
+ * -> kbd-xxx VT trigger
+ * -> vt::xxx VT LED
+ * -> input EV_DEV events (in vt_led_cb)
+ *
+ * KDSETLED directly triggers vt::xxx LEDs.
+ *
+ * Userland can however choose the trigger for the vt::numl LED, or
+ * independently choose the trigger for any inputx::numl LED.
+ */
+
+/* We route VT keyboard "leds" through triggers */
+static void kbd_ledstate_trigger_activate(struct led_classdev *cdev);
+
+static struct led_trigger ledtrig_ledstate[] = {
+#define DEFINE_LEDSTATE_TRIGGER(kbd_led, nam) \
+ [kbd_led] = { \
+ .name = nam, \
+ .activate = kbd_ledstate_trigger_activate, \
+ }
+ DEFINE_LEDSTATE_TRIGGER(VC_SCROLLOCK, "kbd-scrollock"),
+ DEFINE_LEDSTATE_TRIGGER(VC_NUMLOCK, "kbd-numlock"),
+ DEFINE_LEDSTATE_TRIGGER(VC_CAPSLOCK, "kbd-capslock"),
+ DEFINE_LEDSTATE_TRIGGER(VC_KANALOCK, "kbd-kanalock"),
+#undef DEFINE_LEDSTATE_TRIGGER
+};
+
+static int input_leds[] = {
+ [VC_SCROLLOCK] = LED_SCROLLL,
+ [VC_NUMLOCK] = LED_NUML,
+ [VC_CAPSLOCK] = LED_CAPSL,
+ [VC_KANALOCK] = LED_KANA,
+};
+
+/* Called on trigger connection, to set initial state */
+static void kbd_ledstate_trigger_activate(struct led_classdev *cdev)
+{
+ struct led_trigger *trigger = cdev->trigger;
+ int led = trigger - ledtrig_ledstate;
+
+ tasklet_disable(&keyboard_tasklet);
+ led_trigger_event(trigger, ledstate & (1 << led) ? LED_FULL : LED_OFF);
+ tasklet_enable(&keyboard_tasklet);
+}
+
+/* We route VT keyboard lockstates through triggers */
+static void kbd_lockstate_trigger_activate(struct led_classdev *cdev);
+
+static struct led_trigger ledtrig_lockstate[] = {
+#define DEFINE_LOCKSTATE_TRIGGER(kbd_led, nam) \
+ [kbd_led] = { \
+ .name = nam, \
+ .activate = kbd_lockstate_trigger_activate, \
+ }
+ DEFINE_LOCKSTATE_TRIGGER(VC_SHIFTLOCK, "kbd-shiftlock"),
+ DEFINE_LOCKSTATE_TRIGGER(VC_ALTGRLOCK, "kbd-altgrlock"),
+ DEFINE_LOCKSTATE_TRIGGER(VC_CTRLLOCK, "kbd-ctrllock"),
+ DEFINE_LOCKSTATE_TRIGGER(VC_ALTLOCK, "kbd-altlock"),
+ DEFINE_LOCKSTATE_TRIGGER(VC_SHIFTLLOCK, "kbd-shiftllock"),
+ DEFINE_LOCKSTATE_TRIGGER(VC_SHIFTRLOCK, "kbd-shiftrlock"),
+ DEFINE_LOCKSTATE_TRIGGER(VC_CTRLLLOCK, "kbd-ctrlllock"),
+ DEFINE_LOCKSTATE_TRIGGER(VC_CTRLRLOCK, "kbd-ctrlrlock"),
+#undef DEFINE_LOCKSTATE_TRIGGER
+};
+
+/* Called on trigger connection, to set initial state */
+static void kbd_lockstate_trigger_activate(struct led_classdev *cdev)
+{
+ struct led_trigger *trigger = cdev->trigger;
+ int led = trigger - ledtrig_lockstate;
+
+ tasklet_disable(&keyboard_tasklet);
+ led_trigger_event(trigger, lockstate & (1 << led) ? LED_FULL : LED_OFF);
+ tasklet_enable(&keyboard_tasklet);
+}
+
+/* Handler for VT LEDs, scheduling injecting input events in a worker */
+static void vt_led_set(struct led_classdev *cdev,
+ enum led_brightness brightness);
+static struct led_classdev vt_leds[LED_CNT] = {
+#define DEFINE_INPUT_LED(vt_led, nam, deftrig) \
+ [vt_led] = { \
+ .name = "vt::"nam, \
+ .max_brightness = 1, \
+ .brightness_set = vt_led_set, \
+ .default_trigger = deftrig, \
+ }
+/* Default triggers for the VT LEDs just correspond to the legacy
+ * usage. */
+ DEFINE_INPUT_LED(LED_NUML, "numl", "kbd-numlock"),
+ DEFINE_INPUT_LED(LED_CAPSL, "capsl", "kbd-capslock"),
+ DEFINE_INPUT_LED(LED_SCROLLL, "scrolll", "kbd-scrollock"),
+ DEFINE_INPUT_LED(LED_COMPOSE, "compose", NULL),
+ DEFINE_INPUT_LED(LED_KANA, "kana", "kbd-kanalock"),
+ DEFINE_INPUT_LED(LED_SLEEP, "sleep", NULL),
+ DEFINE_INPUT_LED(LED_SUSPEND, "suspend", NULL),
+ DEFINE_INPUT_LED(LED_MUTE, "mute", NULL),
+ DEFINE_INPUT_LED(LED_MISC, "misc", NULL),
+ DEFINE_INPUT_LED(LED_MAIL, "mail", NULL),
+ DEFINE_INPUT_LED(LED_CHARGING, "charging", NULL),
+};
+
+static struct work_struct vt_led_work[LED_CNT];
+static char vt_led_state[LED_CNT];
+
+/* Emit input events to actually update one LED */
+static int kbd_update_leds_helper(struct input_handle *handle, void *data)
+{
+ int led = *(int *)data;
+
+ if (test_bit(EV_LED, handle->dev->evbit)) {
+ input_inject_event(handle, EV_LED, led, vt_led_state[led]);
+ input_inject_event(handle, EV_SYN, SYN_REPORT, 0);
+ }
+
+ return 0;
+}
+
+/* Emit input events to actually update one LED on all keyboards */
+static void vt_led_cb(struct work_struct *work)
+{
+ int led = work - vt_led_work;
+
+ input_handler_for_each_handle(&kbd_handler, &led,
+ kbd_update_leds_helper);
+}
+
+/* VT LED state change, scheduling triggering input events for it */
+static void vt_led_set(struct led_classdev *cdev,
+ enum led_brightness brightness)
+{
+ int led = cdev - vt_leds;
+
+ vt_led_state[led] = !!brightness;
+ schedule_work(&vt_led_work[led]);
+}
+
+/*
* The leds display either (i) the status of NumLock, CapsLock, ScrollLock,
* or (ii) whatever pattern of lights people want to show using KDSETLED,
* or (iii) specified bits of specified words in kernel memory.
@@ -995,20 +1137,6 @@ static inline unsigned char getleds(void
return kb->ledflagstate;
}
-static int kbd_update_leds_helper(struct input_handle *handle, void *data)
-{
- unsigned char leds = *(unsigned char *)data;
-
- if (test_bit(EV_LED, handle->dev->evbit)) {
- input_inject_event(handle, EV_LED, LED_SCROLLL, !!(leds & 0x01));
- input_inject_event(handle, EV_LED, LED_NUML, !!(leds & 0x02));
- input_inject_event(handle, EV_LED, LED_CAPSL, !!(leds & 0x04));
- input_inject_event(handle, EV_SYN, SYN_REPORT, 0);
- }
-
- return 0;
-}
-
/**
* vt_get_leds - helper for braille console
* @console: console to read
@@ -1085,26 +1213,39 @@ void vt_kbd_con_stop(int console)
}
/*
- * This is the tasklet that updates LED state on all keyboards
- * attached to the box. The reason we use tasklet is that we
- * need to handle the scenario when keyboard handler is not
- * registered yet but we already getting updates from the VT to
- * update led state.
+ * This is the tasklet that updates LED state of all LED triggers, which will
+ * thus update the VT LED status, and eventually submit input events.
+ * The reason we use tasklet is that we need to handle the scenario when
+ * keyboard handler is not registered yet but we already getting updates
+ * from the VT to update led state.
*/
static void kbd_bh(unsigned long dummy)
{
unsigned char leds;
unsigned long flags;
-
+ int i;
+
spin_lock_irqsave(&led_lock, flags);
leds = getleds();
spin_unlock_irqrestore(&led_lock, flags);
if (leds != ledstate) {
- input_handler_for_each_handle(&kbd_handler, &leds,
- kbd_update_leds_helper);
+ for (i = 0; i < ARRAY_SIZE(ledtrig_ledstate); i++)
+ if ((leds ^ ledstate) & (1 << i))
+ led_trigger_event(&ledtrig_ledstate[i],
+ leds & (1 << i)
+ ? LED_FULL : LED_OFF);
ledstate = leds;
}
+
+ if (kbd->lockstate != lockstate) {
+ for (i = 0; i < ARRAY_SIZE(ledtrig_lockstate); i++)
+ if ((kbd->lockstate ^ lockstate) & (1 << i))
+ led_trigger_event(&ledtrig_lockstate[i],
+ kbd->lockstate & (1 << i)
+ ? LED_FULL : LED_OFF);
+ lockstate = kbd->lockstate;
+ }
}
DECLARE_TASKLET_DISABLED(keyboard_tasklet, kbd_bh, 0);
@@ -1448,10 +1589,13 @@ static void kbd_disconnect(struct input_
*/
static void kbd_start(struct input_handle *handle)
{
+ int i;
+
tasklet_disable(&keyboard_tasklet);
if (ledstate != 0xff)
- kbd_update_leds_helper(handle, &ledstate);
+ for (i = 0; i < ARRAY_SIZE(ledtrig_ledstate); i++)
+ kbd_update_leds_helper(handle, &input_leds[i]);
tasklet_enable(&keyboard_tasklet);
}
@@ -1501,6 +1645,26 @@ int __init kbd_init(void)
if (error)
return error;
+ for (i = 0; i < ARRAY_SIZE(ledtrig_ledstate); i++) {
+ error = led_trigger_register(&ledtrig_ledstate[i]);
+ if (error)
+ pr_err("error %d while registering trigger %s\n",
+ error, ledtrig_ledstate[i].name);
+ }
+
+ for (i = 0; i < ARRAY_SIZE(ledtrig_lockstate); i++) {
+ error = led_trigger_register(&ledtrig_lockstate[i]);
+ if (error)
+ pr_err("error %d while registering trigger %s\n",
+ error, ledtrig_lockstate[i].name);
+ }
+
+ for (i = 0; i < LED_CNT; i++)
+ if (vt_leds[i].name) {
+ led_classdev_register(NULL, &vt_leds[i]);
+ INIT_WORK(&vt_led_work[i], vt_led_cb);
+ }
+
tasklet_enable(&keyboard_tasklet);
tasklet_schedule(&keyboard_tasklet);
--- a/Documentation/leds/leds-class.txt
+++ b/Documentation/leds/leds-class.txt
@@ -2,9 +2,6 @@
LED handling under Linux
========================
-If you're reading this and thinking about keyboard leds, these are
-handled by the input subsystem and the led class is *not* needed.
-
In its simplest form, the LED class just allows control of LEDs from
userspace. LEDs appear in /sys/class/leds/. The maximum brightness of the
LED is defined in max_brightness file. The brightness file will set the brightness
--- a/drivers/leds/Kconfig
+++ b/drivers/leds/Kconfig
@@ -11,9 +11,6 @@ menuconfig NEW_LEDS
Say Y to enable Linux LED support. This allows control of supported
LEDs from both userspace and optionally, by kernel events (triggers).
- This is not related to standard keyboard LEDs which are controlled
- via the input system.
-
if NEW_LEDS
config LEDS_CLASS
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