platform/x86: fujitsu-laptop: Simplify soft key handling

The hardcoded BIT(X) used in the soft key handling can be confusing and
prone to errors.

Instead, use the status FLAG_* defines for the sparse keymap index.
Rather than check for each known bit, use a bitmask to filter for all
known soft keys, and use the for_each_set_bit iterator.

Cc: Jan-Marek Glogowski <glogow@fbihome.de>
Cc: Michał Kępień <kernel@kempniu.pl>
Reviewed-by: Jonathan Woithe <jwoithe@just42.net>
Signed-off-by: Darren Hart (VMware) <dvhart@infradead.org>

drivers/platform/x86/fujitsu-laptop.c

@@ -91,6 +91,9 @@
 #define FLAG_RFKILL			BIT(5)
 #define FLAG_LID			BIT(8)
 #define FLAG_DOCK			BIT(9)
+#define FLAG_TOUCHPAD_TOGGLE		BIT(26)
+#define FLAG_MICMUTE			BIT(29)
+#define FLAG_SOFTKEYS			(FLAG_RFKILL | FLAG_TOUCHPAD_TOGGLE | FLAG_MICMUTE)
 
 /* FUNC interface - LED control */
 #define FUNC_LED_OFF			BIT(0)
@@ -461,9 +464,10 @@ static const struct key_entry keymap_default[] = {
 	{ KE_KEY, KEY3_CODE,            { KEY_PROG3 } },
 	{ KE_KEY, KEY4_CODE,            { KEY_PROG4 } },
 	{ KE_KEY, KEY5_CODE,            { KEY_RFKILL } },
-	{ KE_KEY, BIT(5),    { KEY_RFKILL } },
-	{ KE_KEY, BIT(26),   { KEY_TOUCHPAD_TOGGLE } },
-	{ KE_KEY, BIT(29),   { KEY_MICMUTE } },
+	/* Soft keys read from status flags */
+	{ KE_KEY, FLAG_RFKILL,          { KEY_RFKILL } },
+	{ KE_KEY, FLAG_TOUCHPAD_TOGGLE, { KEY_TOUCHPAD_TOGGLE } },
+	{ KE_KEY, FLAG_MICMUTE,         { KEY_MICMUTE } },
 	{ KE_END, 0 }
 };
 
@@ -903,7 +907,8 @@ static void acpi_fujitsu_laptop_release(struct acpi_device *device)
 static void acpi_fujitsu_laptop_notify(struct acpi_device *device, u32 event)
 {
 	struct fujitsu_laptop *priv = acpi_driver_data(device);
-	int scancode, i = 0, ret;
+	unsigned long flags;
+	int scancode, i = 0;
 	unsigned int irb;
 
 	if (event != ACPI_FUJITSU_NOTIFY_CODE) {
@@ -930,21 +935,17 @@ static void acpi_fujitsu_laptop_notify(struct acpi_device *device, u32 event)
 					 "Unknown GIRB result [%x]\n", irb);
 	}
 
-	/* On some models (first seen on the Skylake-based Lifebook
-	 * E736/E746/E756), the touchpad toggle hotkey (Fn+F4) is
-	 * handled in software; its state is queried using FUNC_FLAGS
+	/*
+	 * First seen on the Skylake-based Lifebook E736/E746/E756), the
+	 * touchpad toggle hotkey (Fn+F4) is handled in software. Other models
+	 * have since added additional "soft keys". These are reported in the
+	 * status flags queried using FUNC_FLAGS.
 	 */
-	if (priv->flags_supported & (BIT(5) | BIT(26) | BIT(29))) {
-		ret = call_fext_func(device, FUNC_FLAGS, 0x1, 0x0, 0x0);
-		if (ret & BIT(5))
-			sparse_keymap_report_event(priv->input,
-						   BIT(5), 1, true);
-		if (ret & BIT(26))
-			sparse_keymap_report_event(priv->input,
-						   BIT(26), 1, true);
-		if (ret & BIT(29))
-			sparse_keymap_report_event(priv->input,
-						   BIT(29), 1, true);
+	if (priv->flags_supported & (FLAG_SOFTKEYS)) {
+		flags = call_fext_func(device, FUNC_FLAGS, 0x1, 0x0, 0x0);
+		flags &= (FLAG_SOFTKEYS);
+		for_each_set_bit(i, &flags, BITS_PER_LONG)
+			sparse_keymap_report_event(priv->input, BIT(i), 1, true);
 	}
 }