[PATCH v7 2/2] media: V3s: Add support for Allwinner CSI.
hverkuil at xs4all.nl
Mon Feb 26 03:06:37 PST 2018
On 01/30/2018 03:48 AM, Yong wrote:
> On Mon, 29 Jan 2018 13:49:14 -0800
> Randy Dunlap <rdunlap at infradead.org> wrote:
>> On 01/29/2018 01:21 AM, Yong Deng wrote:
>>> Allwinner V3s SoC features two CSI module. CSI0 is used for MIPI CSI-2
>>> interface and CSI1 is used for parallel interface. This is not
>>> documented in datasheet but by test and guess.
>>> This patch implement a v4l2 framework driver for it.
>>> Currently, the driver only support the parallel interface. MIPI-CSI2,
>>> ISP's support are not included in this patch.
>>> Tested-by: Maxime Ripard <maxime.ripard at free-electrons.com>
>>> Signed-off-by: Yong Deng <yong.deng at magewell.com>
>> A previous version (I think v6) had a build error with the use of
>> PHYS_OFFSET, so Kconfig was modified to depend on ARM and ARCH_SUNXI
>> (one of which seems to be overkill). As is here, the COMPILE_TEST piece is
>> meaningless for all arches except ARM. If you care enough for COMPILE_TEST
>> (and I would), then you could make COMPILE_TEST useful on any arch by
>> removing the "depends on ARM" (the ARCH_SUNXI takes care of that) and by
>> having an alternate value for PHYS_OFFSET, like so:
>> +#if defined(CONFIG_COMPILE_TEST) && !defined(PHYS_OFFSET)
>> +#define PHYS_OFFSET 0
>> With those 2 changes, the driver builds for me on x86_64.
> I have considered this method.
> But it's so sick to put these code in dirver (for my own). I mean
> this is meaningless for the driver itself and make people confused.
> I grepped the driver/ code and I found many drivers writing Kconfig
> like this. For example:
> ARM && COMPILE_TEST
> MIPS && COMPILE_TEST
> PPC64 && COMPILE_TEST
> BTW, for my own, I do not care about COMPILE_TEST.
There was a discussion about this in the v6 patch, but it petered out.
I want to merge this driver, but I would very much prefer that this
compiles with COMPILE_TEST. So unless someone has a better solution, then
adding 'hack' that defines PHYS_OFFSET to 0 for COMPILE_TEST would be required.
Otherwise this driver looks good, so it is just this issue blocking it.
>>> diff --git a/drivers/media/platform/sunxi/sun6i-csi/Kconfig b/drivers/media/platform/sunxi/sun6i-csi/Kconfig
>>> new file mode 100644
>>> index 0000000..f80c965
>>> --- /dev/null
>>> +++ b/drivers/media/platform/sunxi/sun6i-csi/Kconfig
>>> @@ -0,0 +1,10 @@
>>> +config VIDEO_SUN6I_CSI
>>> + tristate "Allwinner V3s Camera Sensor Interface driver"
>>> + depends on ARM
>>> + depends on VIDEO_V4L2 && COMMON_CLK && VIDEO_V4L2_SUBDEV_API && HAS_DMA
>>> + depends on ARCH_SUNXI || COMPILE_TEST
>>> + select VIDEOBUF2_DMA_CONTIG
>>> + select REGMAP_MMIO
>>> + select V4L2_FWNODE
>>> + ---help---
>>> + Support for the Allwinner Camera Sensor Interface Controller on V3s.
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