From f850e64037cc6ba703a8a58b59e86378743b164e Mon Sep 17 00:00:00 2001
From: Paolo Bonzini <pbonzini@redhat.com>
Date: Mon, 19 Jun 2017 13:22:34 +0200
Subject: [PATCH 1/2] add volume down and volume up keys

---
 input/input_keymaps.c              | 5 +++++
 libretro-common/include/libretro.h | 3 +++
 2 files changed, 8 insertions(+)

diff --git a/input/input_keymaps.c b/input/input_keymaps.c
index ddd900a45fae..313a98a9a855 100644
--- a/input/input_keymaps.c
+++ b/input/input_keymaps.c
@@ -189,6 +189,8 @@ const struct input_key_map input_config_key_map[] = {
    { "subtract", RETROK_KP_MINUS },
    { "kp_plus", RETROK_KP_PLUS },
    { "kp_minus", RETROK_KP_MINUS },
+   { "volume-", RETROK_VOLUMEDOWN },
+   { "volume+", RETROK_VOLUMEUP },
    { "f1", RETROK_F1 },
    { "f2", RETROK_F2 },
    { "f3", RETROK_F3 },
@@ -1087,6 +1089,9 @@ const struct rarch_key_map rarch_key_map_linux[] = {
    { KEY_EURO, RETROK_EURO },
 #endif
    { KEY_UNDO, RETROK_UNDO },
+   { KEY_VOLUMEDOWN, RETROK_VOLUMEDOWN },
+   { KEY_VOLUMEUP, RETROK_VOLUMEUP },
+
    { 0, RETROK_UNKNOWN },
 };
 #endif
diff --git a/libretro-common/include/libretro.h b/libretro-common/include/libretro.h
index b100865c5a2e..d486ef226560 100644
--- a/libretro-common/include/libretro.h
+++ b/libretro-common/include/libretro.h
@@ -422,6 +422,9 @@ enum retro_key
    RETROK_EURO           = 321,
    RETROK_UNDO           = 322,
 
+   RETROK_VOLUMEDOWN     = 323,
+   RETROK_VOLUMEUP       = 324,
+
    RETROK_LAST,
 
    RETROK_DUMMY          = INT_MAX /* Ensure sizeof(enum) == sizeof(int) */

From d5cdbca3228599952fe5e44b6d84a6863e88f946 Mon Sep 17 00:00:00 2001
From: Paolo Bonzini <pbonzini@redhat.com>
Date: Mon, 19 Jun 2017 12:34:01 +0200
Subject: [PATCH 2/2] add support for remote control devices and other
 ID_INPUT_KEY devices

* the remote control presents itself as ID_INPUT_KEY, not
ID_INPUT_KEYBOARD.  However, ID_INPUT_KEYBOARD is a subset of
ID_INPUT_KEY.

* the remote control lacks the backspace and enter keys, which are hard
coded in RetroArch. It has "back" and "ok" instead, so map those to
RETROK_BACKSPACE and RETROK_ENTER as well.

Remote controls also have no ESC key, but that one is customizable
and I used the Power key of the remote (which already has a mapping
to RETROK_POWER).

The functionality provided is really the bare minimum, but it is enough
to teach a kid "press the power button here to watch TV"; compared to
pressing L1+R1+START+SELECT and navigating to the RetroArch's "quit"
menu item, that hopefully has more chances of success.
---
 input/drivers/udev_input.c | 7 ++++---
 input/input_keymaps.c      | 4 ++++
 2 files changed, 8 insertions(+), 3 deletions(-)

diff --git a/input/drivers/udev_input.c b/input/drivers/udev_input.c
index 01b62e0c78df..c49dd6d0d542 100644
--- a/input/drivers/udev_input.c
+++ b/input/drivers/udev_input.c
@@ -392,7 +392,7 @@ static void udev_input_handle_hotplug(udev_input_t *udev)
 {
    device_handle_cb cb;
    enum udev_input_dev_type dev_type = UDEV_INPUT_KEYBOARD;
-   const char *val_keyboard          = NULL;
+   const char *val_key               = NULL;
    const char *val_mouse             = NULL;
    const char *val_touchpad          = NULL;
    const char *action                = NULL;
@@ -403,14 +403,15 @@ static void udev_input_handle_hotplug(udev_input_t *udev)
    if (!dev)
       return;
 
-   val_keyboard  = udev_device_get_property_value(dev, "ID_INPUT_KEYBOARD");
+   val_key       = udev_device_get_property_value(dev, "ID_INPUT_KEY");
    val_mouse     = udev_device_get_property_value(dev, "ID_INPUT_MOUSE");
    val_touchpad  = udev_device_get_property_value(dev, "ID_INPUT_TOUCHPAD");
    action        = udev_device_get_action(dev);
    devnode       = udev_device_get_devnode(dev);
 
-   if (val_keyboard && string_is_equal_fast(val_keyboard, "1", 1) && devnode)
+   if (val_key && string_is_equal_fast(val_key, "1", 1) && devnode)
    {
+      /* EV_KEY device, can be a keyboard or a remote control device.  */
       dev_type   = UDEV_INPUT_KEYBOARD;
       cb         = udev_handle_keyboard;
    }
diff --git a/input/input_keymaps.c b/input/input_keymaps.c
index 313a98a9a855..75552cd51771 100644
--- a/input/input_keymaps.c
+++ b/input/input_keymaps.c
@@ -1092,6 +1092,10 @@ const struct rarch_key_map rarch_key_map_linux[] = {
    { KEY_VOLUMEDOWN, RETROK_VOLUMEDOWN },
    { KEY_VOLUMEUP, RETROK_VOLUMEUP },
 
+   /* Extra keys for remote controls.  */
+   { KEY_OK, RETROK_RETURN },
+   { KEY_BACK, RETROK_BACKSPACE },
+
    { 0, RETROK_UNKNOWN },
 };
 #endif