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Date:   Fri, 7 Oct 2022 15:12:47 +0300
From:   Laurent Pinchart <laurent.pinchart@ideasonboard.com>
To:     Sakari Ailus <sakari.ailus@iki.fi>
Cc:     Dave Stevenson <dave.stevenson@raspberrypi.com>,
        Jacopo Mondi <jacopo@jmondi.org>,
        Krzysztof =?utf-8?Q?Ha=C5=82asa?= <khalasa@piap.pl>,
        Mauro Carvalho Chehab <mchehab@kernel.org>,
        linux-media@vger.kernel.org
Subject: Re: [PATCH 01/10] media: ar0521: Implement enum_frame_sizes
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On Fri, Oct 07, 2022 at 03:05:22PM +0300, Sakari Ailus wrote:
> Hi Dave,
> 
> On Fri, Oct 07, 2022 at 11:32:27AM +0100, Dave Stevenson wrote:
> > The datasheet and register reference have a fair number of references
> > to SMIA standards. I wonder if the CCS driver can take over from this
> > driver entirely....
> 
> A lot of the configuration of basic features in the driver appears to be
> going to CCS MSR space. While it's possible to do additional writes to the
> MSR register space based on standard CCS register writes, semantics still
> needs to match.
> 
> It is possible to support many sensors with additional CCS static data that
> provides the limit and capability values, too, but to me this sensor
> doesn't appear like an obvious candidate for that.

There are also lots of registers in the standard CCS space that don't
match the CCS specification. I think a custom driver is needed.

-- 
Regards,

Laurent Pinchart