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 <[email protected]> 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
