From: Marek Vasut Date: Thu, 15 Jun 2023 20:15:11 +0000 (+0200) Subject: drm: bridge: samsung-dsim: Drain command transfer FIFO before transfer X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=14806c641582;p=linux.git drm: bridge: samsung-dsim: Drain command transfer FIFO before transfer Wait until the command transfer FIFO is empty before loading in the next command. The previous behavior where the code waited until command transfer FIFO was not full suffered from transfer corruption, where the last command in the FIFO could be overwritten in case the FIFO indicates not full, but also does not have enough space to store another transfer yet. Signed-off-by: Marek Vasut Reviewed-by: Jagan Teki Tested-by: Jagan Teki # imx8mm-icore Link: https://patchwork.freedesktop.org/patch/msgid/20230615201511.565923-1-marex@denx.de --- diff --git a/drivers/gpu/drm/bridge/samsung-dsim.c b/drivers/gpu/drm/bridge/samsung-dsim.c index 043b8109e64aa..9b7a00bafeaaa 100644 --- a/drivers/gpu/drm/bridge/samsung-dsim.c +++ b/drivers/gpu/drm/bridge/samsung-dsim.c @@ -1009,7 +1009,7 @@ static int samsung_dsim_wait_for_hdr_fifo(struct samsung_dsim *dsi) do { u32 reg = samsung_dsim_read(dsi, DSIM_FIFOCTRL_REG); - if (!(reg & DSIM_SFR_HEADER_FULL)) + if (reg & DSIM_SFR_HEADER_EMPTY) return 0; if (!cond_resched())