lkml.org 
[lkml]   [2017]   [Oct]   [31]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 2/2] drm/panel: Enable DSI transactions on the RPi panel.
Date
It turns out that I had just mistaken what type of write the register
writes were supposed to be, using DCS instead of generic long writes.

Switching to transactions instead of using the atmel as a bridge also
seems to resolve the sparkling pixels problem I've had.

Signed-off-by: Eric Anholt <eric@anholt.net>
Fixes: 2f733d6194bd ("drm/panel: Add support for the Raspberry Pi 7" Touchscreen.")
---
drivers/gpu/drm/panel/panel-raspberrypi-touchscreen.c | 14 +-------------
1 file changed, 1 insertion(+), 13 deletions(-)

diff --git a/drivers/gpu/drm/panel/panel-raspberrypi-touchscreen.c b/drivers/gpu/drm/panel/panel-raspberrypi-touchscreen.c
index d964d454e4ae..2c9c9722734f 100644
--- a/drivers/gpu/drm/panel/panel-raspberrypi-touchscreen.c
+++ b/drivers/gpu/drm/panel/panel-raspberrypi-touchscreen.c
@@ -238,12 +238,6 @@ static void rpi_touchscreen_i2c_write(struct rpi_touchscreen *ts,

static int rpi_touchscreen_write(struct rpi_touchscreen *ts, u16 reg, u32 val)
{
-#if 0
- /* The firmware uses LP DSI transactions like this to bring up
- * the hardware, which should be faster than using I2C to then
- * pass to the Toshiba. However, I was unable to get it to
- * work.
- */
u8 msg[] = {
reg,
reg >> 8,
@@ -253,13 +247,7 @@ static int rpi_touchscreen_write(struct rpi_touchscreen *ts, u16 reg, u32 val)
val >> 24,
};

- mipi_dsi_dcs_write_buffer(ts->dsi, msg, sizeof(msg));
-#else
- rpi_touchscreen_i2c_write(ts, REG_WR_ADDRH, reg >> 8);
- rpi_touchscreen_i2c_write(ts, REG_WR_ADDRL, reg);
- rpi_touchscreen_i2c_write(ts, REG_WRITEH, val >> 8);
- rpi_touchscreen_i2c_write(ts, REG_WRITEL, val);
-#endif
+ mipi_dsi_generic_write(ts->dsi, msg, sizeof(msg));

return 0;
}
--
2.15.0
\
 
 \ /
  Last update: 2017-10-31 20:34    [W:0.049 / U:0.560 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site