Hi Rob, On Monday, December 17, 2012, Rob Clark wrote:
> On Mon, Dec 17, 2012 at 8:39 AM, Rob Clark <robdclark at > gmail.com<javascript:;>> > wrote: > >> I'm not very enthusiastic about adding ti-lcdc specific panel/chip > >> drivers. It's not really a big deal if it's only kernel code, but you > >> add device-tree bindings also, which is an external API that you need to > >> support after adding it. > >> > >> I'd rather see the energy put to common display framework, and get this > >> whole panel/chip driver issue solved in a generic manner. > > > > yeah, I was expecting to migrate to CDF once it exists, but needed > > something for now. I'm using the exercise to get my thoughts straight > > on how CDF should fit into KMS. (One thing I plan to add support for > > is an i2c connected hdmi encoder.. which looks like it would fit well > > in drivers/gpu/drm/i2c.. so the drm encoder-slave stuff might be the > > way.) > > > > If you have any suggestions on the DT bindings, I'd like to hear 'em. > > btw, a little bit of-topic, but speaking of DT... > > Anybody have any clue about how backlight devices are supposed to work > in this brave new DT world? See Runtime interpreted power sequences here: http://lkml.indiana.edu/hypermail/linux/kernel/1208.2/00029.html It is an attempt to address this need. Thanks, Sekhar In the old days, the board file would > stuff a fxn ptr to control backlight in pdata for the driver. But we > don't have this any more. I think I need some way to retrieve the > 'struct backlight_device' ptr associated with the panel driver, so > that the appropriate dpms fxn ptrs can enable/disable the backlight. > > I'm thinking the dt file should have something that looks roughly like: > > /* Settings for CDTech_S035Q01 / LCD3 cape: */ > panel { > compatible = "lcdc,panel"; > pinctrl-names = "default"; > pinctrl-0 = <&bone_lcd3_cape_lcd_pins>; > panel-info { > ac-bias = <255>; > ac-bias-intrpt = <0>; > dma-burst-sz = <16>; > bpp = <16>; > fdd = <0x80>; > tft-alt-mode = <0>; > stn-565-mode = <0>; > mono-8bit-mode = <0>; > invert-line-clock = <1>; > invert-frm-clock = <1>; > sync-edge = <0>; > sync-ctrl = <1>; > raster-order = <0>; > fifo-th = <0>; > }; > display-timings { > native-mode = <&timing0>; > timing0: 320x240 { > hactive = <320>; > vactive = <240>; > hback-porch = <21>; > hfront-porch = <58>; > hsync-len = <47>; > vback-porch = <11>; > vfront-porch = <23>; > vsync-len = <2>; > clock-frequency = <8000000>; > }; > }; > > backlight { > compatible = "tps65217-backlight"; > isel = <1>; > fdim = <200>; > > tps = <&tps>; /* link to the tps */ > brightness = <100>; > }; > }; > > display-timings is based on the of-videomode helpers patch.. > panel-info probably needs to be made to be something more generic, but > we need something to know how to configure the crtc properly.. > > but I'm not quite sure what to do with the backlight.. > > BR, > -R > > _______________________________________________ > linux-arm-kernel mailing list > linux-arm-kernel at lists.infradead.org <javascript:;> > http://lists.infradead.org/mailman/listinfo/linux-arm-kernel > -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.freedesktop.org/archives/dri-devel/attachments/20121217/4154d6df/attachment-0001.html>
