From af9470b26dc6c3a8f9ef460c90e34a66ce4f5f1d Mon Sep 17 00:00:00 2001 From: Lars Poeschel Date: Tue, 3 Nov 2020 10:58:26 +0100 Subject: auxdisplay: charlcd: Do not print chars at end of line Skip printing characters at the end of a display line. This fits to the behaviour we already had, that the cursor is nailed to the last position of a line. This might slightly change behaviour. On hd44780 displays with one or two lines the previous implementation did still write characters to the buffer of the display even if they are currently not visible. The shift_display command could be used to set the "viewing window" to a new position in the buffer and then you could see the characters previously written. This described behaviour does not work for hd44780 displays with more than two display lines. There simply is not enough buffer. So the behaviour was a bit inconsistent across different displays. The new behaviour is to stop writing characters at the end of a visible line, even if there would be room in the buffer. This allows us to have an easy implementation, that should behave equal on all supported displays. This is not hd44780 hardware dependent anymore. Reviewed-by: Willy Tarreau Signed-off-by: Lars Poeschel Signed-off-by: Miguel Ojeda --- drivers/auxdisplay/charlcd.c | 3 +++ 1 file changed, 3 insertions(+) (limited to 'drivers/auxdisplay') diff --git a/drivers/auxdisplay/charlcd.c b/drivers/auxdisplay/charlcd.c index ef10b5ca0e16..f43430e9dcee 100644 --- a/drivers/auxdisplay/charlcd.c +++ b/drivers/auxdisplay/charlcd.c @@ -111,6 +111,9 @@ static void charlcd_home(struct charlcd *lcd) static void charlcd_print(struct charlcd *lcd, char c) { + if (lcd->addr.x >= lcd->width) + return; + if (lcd->char_conv) c = lcd->char_conv[(unsigned char)c]; -- cgit v1.2.3