[U-Boot] [PATCH 7/8] usb: kbd: Properly translate up/down arrow keys

[Andre Przywara]

So far arrows key pressed on an USB keyboard got translated to some
low ASCII control sequences (Ctrl+N, Ctrl+P). Some programs understand
these codes, but the standard for those keys is to use ANSI control
sequences for cursor movement (ESC [ A).
Our own boot menu is a victim of this, currently we cannot change the
selection with an USB keyboard due to this.

Since we already implement a queue for USB key codes, we can just insert
the three character ANSI sequence into the key buffer. This fixes the
bootmenu, and is more universal for other users (UEFI) as well.

Signed-off-by: Andre Przywara <andre.przywara at arm.com>
---
 common/usb_kbd.c | 24 +++++++++++++++++++++++-
 1 file changed, 23 insertions(+), 1 deletion(-)

diff --git a/common/usb_kbd.c b/common/usb_kbd.c
index 020f0d4117..cc99c6be07 100644
--- a/common/usb_kbd.c
+++ b/common/usb_kbd.c
@@ -145,6 +145,12 @@ static void usb_kbd_put_queue(struct usb_kbd_pdata *data, char c)
 	data->usb_kbd_buffer[data->usb_in_pointer] = c;
 }
 
+static void usb_kbd_put_sequence(struct usb_kbd_pdata *data, char *s)
+{
+	for (; *s; s++)
+		usb_kbd_put_queue(data, *s);
+}
+
 /*
  * Set the LEDs. Since this is used in the irq routine, the control job is
  * issued with a timeout of 0. This means, that the job is queued without
@@ -235,9 +241,25 @@ static int usb_kbd_translate(struct usb_kbd_pdata *data, unsigned char scancode,
 	}
 
 	/* Report keycode if any */
-	if (keycode) {
+	if (keycode)
 		debug("%c", keycode);
+
+	switch (keycode) {
+	case 0x0e:					/* Down arrow key */
+		usb_kbd_put_sequence(data, "\e[B");
+		break;
+	case 0x10:					/* Up arrow key */
+		usb_kbd_put_sequence(data, "\e[A");
+		break;
+	case 0x06:					/* Right arrow key */
+		usb_kbd_put_sequence(data, "\e[C");
+		break;
+	case 0x02:					/* Left arrow key */
+		usb_kbd_put_sequence(data, "\e[D");
+		break;
+	default:
 		usb_kbd_put_queue(data, keycode);
+		break;
 	}
 
 	return 0;
-- 
2.14.5