Hi Rob,<br><br>On Monday, December 17, 2012, Rob Clark  wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">On Mon, Dec 17, 2012 at 8:39 AM, Rob Clark <<a href="javascript:;" onclick="_e(event, 'cvml', 'robdclark@gmail.com')">robdclark@gmail.com</a>> wrote:<br>

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