[PATCH v6 03/22] drm/sun4i: sun6i_mipi_dsi: Setup burst mode timings

Jagan Teki jagan at amarulasolutions.com
Thu Jan 24 19:58:41 UTC 2019


Burst mode display timings are different from conventional
video mode, for burst mode most of the timings hsa, hbp, hfp,
vblk are 0 and hblk is computed as (mode->hdisplay * Bpp)

This patch add burst mode timings and directly goto alloc buffer.

Reference code taken from BSP (from linux-sunxi/
drivers/video/sunxi/disp2/disp/de/lowlevel_sun50iw1/de_dsi.c)

dsi_hsa  = 0;
dsi_hbp  = 0;
dsi_hact = x*dsi_pixel_bits[format]/8;
dsi_hblk = dsi_hact;
dsi_hfp  = 0;
dsi_vblk = 0;

Signed-off-by: Jagan Teki <jagan at amarulasolutions.com>
---
 drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c b/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c
index 813d5523f1c7..0f02bcc997a5 100644
--- a/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c
+++ b/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c
@@ -477,6 +477,12 @@ static void sun6i_dsi_setup_timings(struct sun6i_dsi *dsi,
 
 	/* Do all timing calculations up front to allocate buffer space */
 
+	if (device->mode_flags & MIPI_DSI_MODE_VIDEO_BURST) {
+		hbp = hfp = hsa = vblk = 0;
+		hblk = (mode->hdisplay * Bpp);
+		goto alloc_buf;
+	}
+
 	/*
 	 * A sync period is composed of a blanking packet (4 bytes +
 	 * payload + 2 bytes) and a sync event packet (4 bytes). Its
@@ -515,6 +521,7 @@ static void sun6i_dsi_setup_timings(struct sun6i_dsi *dsi,
 	 */
 	vblk = 0;
 
+alloc_buf:
 	/* How many bytes do we need to send all payloads? */
 	bytes = max_t(size_t, max(max(hfp, hblk), max(hsa, hbp)), vblk);
 	buffer = kmalloc(bytes, GFP_KERNEL);
-- 
2.18.0.321.gffc6fa0e3



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