[U-Boot] [PATCH] sunxi: Add generic defconfigs for A33 Q8 tablets with 1024x600 / 800x480 LCD

Hans de Goede hdegoede at redhat.com
Fri Oct 2 11:24:09 CEST 2015


Hi,

On 02-10-15 10:49, Chen-Yu Tsai wrote:
> On Fri, Sep 25, 2015 at 4:06 PM, Hans de Goede <hdegoede at redhat.com> wrote:
>> Hi,
>>
>> On 25-09-15 04:35, Chen-Yu Tsai wrote:
>>>
>>> On Thu, Sep 24, 2015 at 11:24 PM, Hans de Goede <hdegoede at redhat.com>
>>> wrote:
>>
>>
>> <snip>
>>
>>>> diff --git a/configs/q8_a33_tablet_800x480_defconfig
>>>> b/configs/q8_a33_tablet_800x480_defconfig
>>>> new file mode 100644
>>>> index 0000000..a9c2b62
>>>> --- /dev/null
>>>> +++ b/configs/q8_a33_tablet_800x480_defconfig
>>>> @@ -0,0 +1,24 @@
>>>> +CONFIG_ARM=y
>>>> +CONFIG_ARCH_SUNXI=y
>>>> +CONFIG_MACH_SUN8I_A33=y
>>>> +CONFIG_DRAM_CLK=456
>>>> +CONFIG_DRAM_ZQ=15291
>>>> +CONFIG_USB0_VBUS_PIN="AXP0-VBUS-ENABLE"
>>>> +CONFIG_USB0_VBUS_DET="AXP0-VBUS-DETECT"
>>>> +CONFIG_USB0_ID_DET="PH8"
>>>> +CONFIG_AXP_GPIO=y
>>>>
>>>> +CONFIG_VIDEO_LCD_MODE="x:800,y:480,depth:18,pclk_khz:33000,le:87,ri:167,up:31,lo:13,hs:1,vs:1,sync:3,vmode:0"
>>>
>>>
>>> FYI my q8h-v1.5 uses a slightly different mode line:
>>>
>>>
>>> x:800,y:480,depth:18,pclk_khz:36000,le:45,ri:209,up:22,lo:22,hs:1,vs:1,sync:3,vmode:0
>>
>>
>> Yes, there are multiple modelines floating around for 800x480 panels, I've
>> 2 A13 tablets and the modeline of the fex file from tablet a causes the
>> images
>> to not be properly centered on the screen of tablet b. Luckily the other way
>> around does work, so for the q8_a13_tablet_defconfig I'm using the modeline
>> from the fex file from tablet b. I hope we can do something similar with q8
>> a23 and a33 800x480 tablets.
>>
>> I've been buying q8 tablets with cracked screens (people seem to drop them
>> quite
>> a lot) for cheap from a local 2nd hand website, so now I've 5 ever so
>> slightly
>> different models, I still need to make a generic q8 config for those, and
>> see if
>> I can find a modeline which works on all of them.
>>
>> That modeline should probably be a good one to use for the a33 defconfig
>> too.
>>
>>> I'll find some time to give yours a test.
>
> So it looks like your modeline works as well. I can't see any difference
> between the two on screen.

Great, thanks for testing this.

> Speaking of the screen, mine is slightly off
> vertically. Feels like it is 1 line lower than it should be. And the right
> most end displays partially under the touchscreen with either modeline.

Yeah I've this with some other q8 tablets too, where the black bezel of the
touchscreen slightly overlaps part of the lcd which should be visible, I guess
this can be expected given the prices of these tablets.

Regards,

Hans


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