[PATCH 01/10] drm/sun4i: sun6i_mipi_dsi: Compute burst mode loop N1 instruction delay

Jagan Teki jagan at amarulasolutions.com
Sat Nov 3 10:08:51 UTC 2018


Loop N1 instruction delay for burst mode lcd panel are
computed as per BSP code.

Reference code is available in BSP
(in drivers/video/sunxi/disp2/disp/de/lowlevel_sun50iw1/de_dsi.c)
dsi_dev[sel]->dsi_inst_loop_num.bits.loop_n1=
(panel->lcd_ht-panel->lcd_x)*(150)/(panel->lcd_dclk_freq*8) - 50;
=> (((mode->htotal - mode->hdisplay) * 150) / ((mode->clock / 1000) * 8)) - 50;

So use the similar computation for loop N1 delay.

Signed-off-by: Jagan Teki <jagan at amarulasolutions.com>
---
 drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c b/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c
index 86430efd9054..da152c21ec62 100644
--- a/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c
+++ b/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c
@@ -394,7 +394,14 @@ static void sun6i_dsi_setup_burst(struct sun6i_dsi *dsi,
 static void sun6i_dsi_setup_inst_loop(struct sun6i_dsi *dsi,
 				      struct drm_display_mode *mode)
 {
-	u16 delay = 50 - 1;
+	struct mipi_dsi_device *device = dsi->device;
+	u16 delay;
+
+	if (device->mode_flags == MIPI_DSI_MODE_VIDEO_BURST)
+		delay = (((mode->htotal - mode->hdisplay) * 150) /
+			((mode->clock / 1000) * 8)) - 50;
+	else
+		delay = 50 - 1;
 
 	regmap_write(dsi->regs, SUN6I_DSI_INST_LOOP_NUM_REG(0),
 		     SUN6I_DSI_INST_LOOP_NUM_N0(50 - 1) |
-- 
2.18.0.321.gffc6fa0e3



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