Hi Marek, On Thu, 3 Aug 2023 19:10:35 +0200 Marek Vasut <marex@xxxxxxx> wrote: > On 8/3/23 17:06, Luca Ceresoli wrote: > > Hi Marek, > > > > On Thu, 3 Aug 2023 16:25:37 +0200 > > Marek Vasut <marex@xxxxxxx> wrote: > > > >> On 8/3/23 16:23, Luca Ceresoli wrote: > >>> Hi Marek, > >> > >> Hi, > >> > >>> On Mon, 31 Jul 2023 23:02:58 +0200 > >>> Marek Vasut <marex@xxxxxxx> wrote: > >>> > >>>> Add support for Innolux G156HCE-L01 15.6" 1920x1080 24bpp > >>>> dual-link LVDS TFT panel. Documentation is available at [1]. > >>> > >>> Interesting, I'm bringing up this exact panel right now and found your > >>> patch. > >>> > >>>> The middle frequency is tuned slightly upward from 70.93 MHz > >>>> to 72 MHz, otherwise the panel shows slight flicker. > >>> > >>> Using 70.93 MHz here does not show any flickering. I even tried going > >>> in the opposite direction and set 70 MHz, and to use different > >>> backlight settings, all without any flickering. > >>> > >>> Do you think you might be using a defective device? Would you have a > >>> chance of testing another sample? > >> > >> I have literally one such display. > >> > >> Which SoC do you use (and if applicable, which bridge) ? > > > > The panel is driven by the DSI-2 output of a i.MX8MP through a TI > > SN65DSI84 bridge. > > I use the LT9211 , so I wonder whether this might be another Lontium > specific oddity. Or maybe not. After checking the LVDS clock with an oscilloscope I discovered I was actually sending 77 MHz. After fixing it I found that my panel (of which I only have one sample as well) does not display any output with pixel clocks <= 75 MHz. It works with clocks >= 76 MHz. I'm trying to get more info about this. Luca -- Luca Ceresoli, Bootlin Embedded Linux and Kernel engineering https://bootlin.com