Hi,
On Tue, Oct 1, 2019 at 1:34 PM Icenowy Zheng icenowy@aosc.io wrote:
According to the BSP source code, when calculating the magic DRQ value outside burst mode, a formula of "lcd_ht - lcd_x - lcd_hbp", which is interpreted as right margin (HFP value). However, currently the sun6i_mipi_dsi driver code calculates it wrongly as HFP + sync length, which lead to timing error.
Fix the DRQ calculation by change it to use HFP.
Signed-off-by: Icenowy Zheng icenowy@aosc.io
drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c b/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c index c86e11631ebc..2d3e822a7739 100644 --- a/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c +++ b/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c @@ -436,9 +436,9 @@ static void sun6i_dsi_setup_burst(struct sun6i_dsi *dsi, SUN6I_DSI_BURST_LINE_SYNC_POINT(SUN6I_DSI_SYNC_POINT));
val = SUN6I_DSI_TCON_DRQ_ENABLE_MODE;
} else if ((mode->hsync_end - mode->hdisplay) > 20) {
} else if ((mode->hsync_start - mode->hdisplay) > 20) { /* Maaaaaagic */
u16 drq = (mode->hsync_end - mode->hdisplay) - 20;
u16 drq = (mode->hsync_start - mode->hdisplay) - 20;
I have similar patch in the ML, which required commit details commented by Chen-Yu [1]. So, I'm trying to send it accordingly, let me know if you have issues.