Re: [PATCH v2 3/7] drm: add Atmel HLCDC Display Controller support

[Boris BREZILLON <boris.brezillon@free-electrons.com>]

Hello JJ,

On 15/06/2014 11:32, Jean-Jacques Hiblot wrote:
>
> On 06/09/2014 06:04 PM, Boris BREZILLON wrote:
>> The Atmel HLCDC (High LCD Controller) IP available on some Atmel SoCs (i.e.
>> at91sam9n12, at91sam9x5 family or sama5d3 family) provides a display
>> controller device.
>>
>> This display controller support at least one primary plane and might
>> provide several overlays and an hardware cursor depending on the IP
>> version.
>>
>> Signed-off-by: Boris BREZILLON <boris.brezillon@free-electrons.com>
>> ---

[...]

>> +	    vm.vfront_porch > 0x40 || vm.vfront_porch < 0 ||
>> +	    vm.vback_porch > 0x40 || vm.vback_porch < 0 ||
>> +	    vm.hfront_porch > 0x200 || vm.hfront_porch < 0 ||
>> +	    vm.hback_porch > 0x200 || vm.hback_porch < 0 ||
>> +	    mode->hdisplay > 2048 || mode->hdisplay < 0 ||
>> +	    mode->vdisplay > 2048 || mode->vdisplay < 0)
>> +		return -EINVAL;
>> +
>> +	regmap_write(regmap, ATMEL_HLCDC_CFG(1),
>> +		     (vm.hsync_len - 1) | ((vm.vsync_len - 1) << 16));
>> +
>> +	regmap_write(regmap, ATMEL_HLCDC_CFG(2),
>> +		     (vm.vfront_porch - 1) | ((vm.vback_porch - 1) << 16));
> Acording to the datasheet, it's vm.vback_porch instead of
> (vm.vback_porch -1).

Oh, nice catch!

I'll check with Atmel that this is not a typo in their datasheet,
because all other fields need the minus 1.

Thanks for your review.

Best Regards,

Boris

-- 
Boris Brezillon, Free Electrons
Embedded Linux and Kernel engineering
http://free-electrons.com