eeepc-laptop: report brightness control events via the input layer

This maps the brightness control events to one of two keys, either
KEY_BRIGHTNESSDOWN or KEY_BRIGHTNESSUP, as needed.

Some mapping has to be done due to the fact that the BIOS reports them as
<base value> + <current brightness index>; the selection is done according to
the sign of the change in brightness (if this is 0, no keypress is reported).

(Ref. http://lists.alioth.debian.org/pipermail/debian-eeepc-devel/2009-April/002001.html)

Signed-off-by: Darren Salt <linux@youmustbejoking.demon.co.uk>
Signed-off-by: Corentin Chary <corentincj@iksaif.net>
Signed-off-by: Len Brown <len.brown@intel.com>

diff --git a/drivers/platform/x86/eeepc-laptop.c b/drivers/platform/x86/eeepc-laptop.c
index e21f7cd..f54cfea 100644 (file)
--- a/drivers/platform/x86/eeepc-laptop.c
+++ b/drivers/platform/x86/eeepc-laptop.c
@@ -166,6 +166,8 @@ static struct key_entry eeepc_keymap[] = {
        {KE_KEY, 0x1b, KEY_ZOOM },
        {KE_KEY, 0x1c, KEY_PROG2 },
        {KE_KEY, 0x1d, KEY_PROG3 },
+       {KE_KEY, NOTIFY_BRN_MIN,     KEY_BRIGHTNESSDOWN },
+       {KE_KEY, NOTIFY_BRN_MIN + 2, KEY_BRIGHTNESSUP },
        {KE_KEY, 0x30, KEY_SWITCHVIDEOMODE },
        {KE_KEY, 0x31, KEY_SWITCHVIDEOMODE },
        {KE_KEY, 0x32, KEY_SWITCHVIDEOMODE },
@@ -512,11 +514,16 @@ static int eeepc_hotk_check(void)
        return 0;
 }
 
-static void notify_brn(void)
+static int notify_brn(void)
 {
+       /* returns the *previous* brightness, or -1 */
        struct backlight_device *bd = eeepc_backlight_device;
-       if (bd)
+       if (bd) {
+               int old = bd->props.brightness;
                bd->props.brightness = read_brightness(bd);
+               return old;
+       }
+       return -1;
 }
 
 static void eeepc_rfkill_notify(acpi_handle handle, u32 event, void *data)
@@ -558,17 +565,33 @@ static void eeepc_hotk_notify(acpi_handle handle, u32 event, void *data)
 {
        static struct key_entry *key;
        u16 count;
+       int brn = -ENODEV;
 
        if (!ehotk)
                return;
        if (event >= NOTIFY_BRN_MIN && event <= NOTIFY_BRN_MAX)
-               notify_brn();
+               brn = notify_brn();
        count = ehotk->event_count[event % 128]++;
        acpi_bus_generate_proc_event(ehotk->device, event, count);
        acpi_bus_generate_netlink_event(ehotk->device->pnp.device_class,
                                        dev_name(&ehotk->device->dev), event,
                                        count);
        if (ehotk->inputdev) {
+               if (brn != -ENODEV) {
+                       /* brightness-change events need special
+                        * handling for conversion to key events
+                        */
+                       if (brn < 0)
+                               brn = event;
+                       else
+                               brn += NOTIFY_BRN_MIN;
+                       if (event < brn)
+                               event = NOTIFY_BRN_MIN; /* brightness down */
+                       else if (event > brn)
+                               event = NOTIFY_BRN_MIN + 2; /* ... up */
+                       else
+                               event = NOTIFY_BRN_MIN + 1; /* ... unchanged */
+               }
                key = eepc_get_entry_by_scancode(event);
                if (key) {
                        switch (key->type) {