linux-kernel - Re: [PATCHv2 9/9] spi: spidev: add Aardvark to device tree compatibility list

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Date:   Fri, 30 Jun 2017 12:51:50 +0100
From:   Mark Brown <broonie@...nel.org>
To:     Amelie DELAUNAY <amelie.delaunay@...com>
Cc:     Rob Herring <robh+dt@...nel.org>,
        Mark Rutland <mark.rutland@....com>,
        Maxime Coquelin <mcoquelin.stm32@...il.com>,
        Alexandre TORGUE <alexandre.torgue@...com>,
        "linux-spi@...r.kernel.org" <linux-spi@...r.kernel.org>,
        "devicetree@...r.kernel.org" <devicetree@...r.kernel.org>,
        "linux-arm-kernel@...ts.infradead.org" 
        <linux-arm-kernel@...ts.infradead.org>,
        "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>
Subject: Re: [PATCHv2 9/9] spi: spidev: add Aardvark to device tree
 compatibility list

On Thu, Jun 29, 2017 at 02:58:43PM +0200, Amelie DELAUNAY wrote:
> On 06/28/2017 08:54 PM, Mark Brown wrote:

> > What does this device actually do and why is spidev a sensible fit for
> > it?

> This device is actually a debugging tool [1] which can work on SPI bus (and
> also I2C). Connected via USB on a PC, it can either acts as an SPI master or
> SPI slave and it can transmit/receive serial data using SPI protocol.
> Polarity, Phase, Bit Order, Frequency can be configured. So this tool is
> really useful during SPI driver development to troubleshoot. And that's why
> spidev driver totally fit for it when used as an SPI slave, for the reason
> described in spidev Documentation: "Developing simple protocols used to talk
> to" Aardvark "acting as SPI slaves, which you may need to change quite
> often".

This doesn't seem like something that should be in DT, it's a tool used
to implement or emulate other things and is no more specific than spidev
itself is.  Whatever it is implementing or emulating should be in DT
instead.

Download attachment "signature.asc" of type "application/pgp-signature" (489 bytes)