Re: [PATCH v5 07/17] drm/sun4i: sun6i_mipi_dsi: Refactor vertical video start delay

From: Maxime Ripard
Date: Wed Jan 16 2019 - 14:18:19 EST


On Sun, Jan 13, 2019 at 01:07:41AM +0530, Jagan Teki wrote:
> > > > > > Again, I cannot help you without the datasheet for the panels you're
> > > > > > trying to submit.
> > > > >
> > > > > The panel bound with Sitronix ST7701 IC
> > > > > http://www.startek-lcd.com/res/starteklcd/pdres/201705/20170512144242904.pdf
> > > >
> > > > It's the controller, not the panel
> > >
> > > As I said before, the datasheet of that panel doesn't have any
> > > information except electrical characteristics and used IC which is
> > > ST7701.
> > >
> > > I have one more panel, which is from Bananapi, S070WV20-CT16 ICN621
> > > please find the attachment for the same.
> > >
> > > Here is some more details of the same.
> > >
> > > https://github.com/yesnoandor/x300/blob/master/kernel/arch/arm/boot/dts/erobbing/x300/x300.dtsi#L81
> > > https://github.com/wxzed/Raspberry_5MIPI_Display/blob/master/I2C_Slave/USER/main.c#L15
> > >
> > > https://github.com/eliot-shao/qcom/blob/master/icn6211_cxn0102/kernel/drivers/video/msm/mdss/mdss_i2c_interface.c#L152
> > > matches timings for
> > > https://github.com/eliot-shao/qcom/blob/master/icn6211_cxn0102/kernel/arch/arm/boot/dts/qcom/dsi-mipi-2-rgb_1280p_video.dtsi#L20
> > >
> > > https://github.com/zestroly/micromat/blob/master/test/raspberry/ICN6211.cpp#L169
> >
> > Where did you get the timings from then?
>
> You mean drm_mode timings, the same panel with RGB available in
> panel-simple[1], and dsi driver in Mailing list[2] and actual DSI
> sequence commands from BSP[3]
>
> [1] https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/commit/drivers/gpu/drm/panel/panel-simple.c?id=7ad8b41cd8f5c2842646d01cdd576663caee04a7
> [2] https://patchwork.kernel.org/patch/10680331/
> [3] https://github.com/BPI-SINOVOIP/BPI-M64-bsp/blob/master/linux-sunxi/drivers/video/sunxi/disp2/disp/lcd/S070WV20_MIPI_RGB.c

So you had no reliable source for the timings then? How do you know if
all your patches that are timing related are right then?

Maxime

--
Maxime Ripard, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com