Input: HID - add support for fn key on Apple PowerBooks

This patch implements support for the fn key on Apple PowerBooks using
USB based keyboards and makes them behave like their ADB counterparts.

Signed-off-by: Michael Hanselmann <linux-kernel@hansmi.ch>
Acked-by: Rene Nussbaumer <linux-kernel@killerfox.forkbomb.ch>
Acked-by: Johannes Berg <johannes@sipsolutions.net>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Vojtech Pavlik <vojtech@suse.cz>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>

1 files changed, 164 insertions, 2 deletions

diff --git a/drivers/usb/input/hid-input.c b/drivers/usb/input/hid-input.c
index 36a08c04c46..cb0d80f4925 100644
--- a/drivers/usb/input/hid-input.c
+++ b/drivers/usb/input/hid-input.c
@@ -73,6 +73,160 @@ static const struct {
 #define map_key_clear(c)	do { map_key(c); clear_bit(c, bit); } while (0)
 #define map_ff_effect(c)	do { set_bit(c, input->ffbit); } while (0)
 
+#ifdef CONFIG_USB_HIDINPUT_POWERBOOK
+
+struct hidinput_key_translation {
+	u16 from;
+	u16 to;
+	u8 flags;
+};
+
+#define POWERBOOK_FLAG_FKEY 0x01
+
+static struct hidinput_key_translation powerbook_fn_keys[] = {
+	{ KEY_BACKSPACE, KEY_DELETE },
+	{ KEY_F1,	KEY_BRIGHTNESSDOWN,	POWERBOOK_FLAG_FKEY },
+	{ KEY_F2,	KEY_BRIGHTNESSUP,	POWERBOOK_FLAG_FKEY },
+	{ KEY_F3,	KEY_MUTE,		POWERBOOK_FLAG_FKEY },
+	{ KEY_F4,	KEY_VOLUMEDOWN,		POWERBOOK_FLAG_FKEY },
+	{ KEY_F5,	KEY_VOLUMEUP,		POWERBOOK_FLAG_FKEY },
+	{ KEY_F6,	KEY_NUMLOCK,		POWERBOOK_FLAG_FKEY },
+	{ KEY_F7,	KEY_SWITCHVIDEOMODE,	POWERBOOK_FLAG_FKEY },
+	{ KEY_F8,	KEY_KBDILLUMTOGGLE,	POWERBOOK_FLAG_FKEY },
+	{ KEY_F9,	KEY_KBDILLUMDOWN,	POWERBOOK_FLAG_FKEY },
+	{ KEY_F10,	KEY_KBDILLUMUP,		POWERBOOK_FLAG_FKEY },
+	{ KEY_UP,	KEY_PAGEUP },
+	{ KEY_DOWN,	KEY_PAGEDOWN },
+	{ KEY_LEFT,	KEY_HOME },
+	{ KEY_RIGHT,	KEY_END },
+	{ }
+};
+
+static struct hidinput_key_translation powerbook_numlock_keys[] = {
+	{ KEY_J,	KEY_KP1 },
+	{ KEY_K,	KEY_KP2 },
+	{ KEY_L,	KEY_KP3 },
+	{ KEY_U,	KEY_KP4 },
+	{ KEY_I,	KEY_KP5 },
+	{ KEY_O,	KEY_KP6 },
+	{ KEY_7,	KEY_KP7 },
+	{ KEY_8,	KEY_KP8 },
+	{ KEY_9,	KEY_KP9 },
+	{ KEY_M,	KEY_KP0 },
+	{ KEY_DOT,	KEY_KPDOT },
+	{ KEY_SLASH,	KEY_KPPLUS },
+	{ KEY_SEMICOLON, KEY_KPMINUS },
+	{ KEY_P,	KEY_KPASTERISK },
+	{ KEY_MINUS,	KEY_KPEQUAL },
+	{ KEY_0,	KEY_KPSLASH },
+	{ KEY_F6,	KEY_NUMLOCK },
+	{ KEY_KPENTER,	KEY_KPENTER },
+	{ KEY_BACKSPACE, KEY_BACKSPACE },
+	{ }
+};
+
+static int usbhid_pb_fnmode = 1;
+module_param_named(pb_fnmode, usbhid_pb_fnmode, int, 0644);
+MODULE_PARM_DESC(pb_fnmode,
+	"Mode of fn key on PowerBooks (0 = disabled, 1 = fkeyslast, 2 = fkeysfirst)");
+
+static struct hidinput_key_translation *find_translation(struct hidinput_key_translation *table, u16 from)
+{
+	struct hidinput_key_translation *trans;
+
+	/* Look for the translation */
+	for (trans = table; trans->from; trans++)
+		if (trans->from == from)
+			return trans;
+
+	return NULL;
+}
+
+static int hidinput_pb_event(struct hid_device *hid, struct input_dev *input,
+			     struct hid_usage *usage, __s32 value)
+{
+	struct hidinput_key_translation *trans;
+
+	if (usage->code == KEY_FN) {
+		if (value) hid->quirks |=  HID_QUIRK_POWERBOOK_FN_ON;
+		else       hid->quirks &= ~HID_QUIRK_POWERBOOK_FN_ON;
+
+		input_event(input, usage->type, usage->code, value);
+
+		return 1;
+	}
+
+	if (usbhid_pb_fnmode) {
+		int do_translate;
+
+		trans = find_translation(powerbook_fn_keys, usage->code);
+		if (trans) {
+			if (test_bit(usage->code, hid->pb_pressed_fn))
+				do_translate = 1;
+			else if (trans->flags & POWERBOOK_FLAG_FKEY)
+				do_translate =
+					(usbhid_pb_fnmode == 2 &&  (hid->quirks & HID_QUIRK_POWERBOOK_FN_ON)) ||
+					(usbhid_pb_fnmode == 1 && !(hid->quirks & HID_QUIRK_POWERBOOK_FN_ON));
+			else
+				do_translate = (hid->quirks & HID_QUIRK_POWERBOOK_FN_ON);
+
+			if (do_translate) {
+				if (value)
+					set_bit(usage->code, hid->pb_pressed_fn);
+				else
+					clear_bit(usage->code, hid->pb_pressed_fn);
+
+				input_event(input, usage->type, trans->to, value);
+
+				return 1;
+			}
+		}
+
+		if (test_bit(usage->code, hid->pb_pressed_numlock) ||
+		    test_bit(LED_NUML, input->led)) {
+			trans = find_translation(powerbook_numlock_keys, usage->code);
+
+			if (trans) {
+				if (value)
+					set_bit(usage->code, hid->pb_pressed_numlock);
+				else
+					clear_bit(usage->code, hid->pb_pressed_numlock);
+
+				input_event(input, usage->type, trans->to, value);
+			}
+
+			return 1;
+		}
+	}
+
+	return 0;
+}
+
+static void hidinput_pb_setup(struct input_dev *input)
+{
+	struct hidinput_key_translation *trans;
+
+	set_bit(KEY_NUMLOCK, input->keybit);
+
+	/* Enable all needed keys */
+	for (trans = powerbook_fn_keys; trans->from; trans++)
+		set_bit(trans->to, input->keybit);
+
+	for (trans = powerbook_numlock_keys; trans->from; trans++)
+		set_bit(trans->to, input->keybit);
+}
+#else
+static inline int hidinput_pb_event(struct hid_device *hid, struct input_dev *input,
+				    struct hid_usage *usage, __s32 value)
+{
+	return 0;
+}
+
+static inline void hidinput_pb_setup(struct input_dev *input)
+{
+}
+#endif
+
 static void hidinput_configure_usage(struct hid_input *hidinput, struct hid_field *field,
 				     struct hid_usage *usage)
 {
@@ -336,7 +490,12 @@ static void hidinput_configure_usage(struct hid_input *hidinput, struct hid_fiel
 
 			set_bit(EV_REP, input->evbit);
 			switch(usage->hid & HID_USAGE) {
-				case 0x003: map_key_clear(KEY_FN);		break;
+				case 0x003:
+					/* The fn key on Apple PowerBooks */
+					map_key_clear(KEY_FN);
+					hidinput_pb_setup(input);
+					break;
+
 				default:    goto ignore;
 			}
 			break;
@@ -493,6 +652,9 @@ void hidinput_hid_event(struct hid_device *hid, struct hid_field *field, struct
 		return;
 	}
 
+	if ((hid->quirks & HID_QUIRK_POWERBOOK_HAS_FN) && hidinput_pb_event(hid, input, usage, value))
+		return;
+
 	if (usage->hat_min < usage->hat_max || usage->hat_dir) {
 		int hat_dir = usage->hat_dir;
 		if (!hat_dir)
@@ -535,7 +697,7 @@ void hidinput_hid_event(struct hid_device *hid, struct hid_field *field, struct
 		return;
 	}
 
-	if((usage->type == EV_KEY) && (usage->code == 0)) /* Key 0 is "unassigned", not KEY_UNKNOWN */
+	if ((usage->type == EV_KEY) && (usage->code == 0)) /* Key 0 is "unassigned", not KEY_UNKNOWN */
 		return;
 
 	input_event(input, usage->type, usage->code, value);