The patch below does not apply to the 4.19-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From b6821b0d9b56386d2bf14806f90ec401468c799f Mon Sep 17 00:00:00 2001 From: Oliver Graute oliver.graute@kococonnector.com Date: Thu, 10 Feb 2022 09:53:22 +0100 Subject: [PATCH] staging: fbtft: fb_st7789v: reset display before initialization

In rare cases the display is flipped or mirrored. This was observed more often in a low temperature environment. A clean reset on init_display() should help to get registers in a sane state.

Fixes: ef8f317795da (staging: fbtft: use init function instead of init sequence) Cc: stable@vger.kernel.org Signed-off-by: Oliver Graute oliver.graute@kococonnector.com Link: https://lore.kernel.org/r/20220210085322.15676-1-oliver.graute@kococonnector... Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org

diff --git a/drivers/staging/fbtft/fb_st7789v.c b/drivers/staging/fbtft/fb_st7789v.c index abe9395a0aef..861a154144e6 100644 --- a/drivers/staging/fbtft/fb_st7789v.c +++ b/drivers/staging/fbtft/fb_st7789v.c @@ -144,6 +144,8 @@ static int init_display(struct fbtft_par *par) { int rc;

+ par->fbtftops.reset(par); + rc = init_tearing_effect_line(par); if (rc) return rc;