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Message-ID: <04b1296ff98a0accbf962a4a4bafc2e85a9869ae.camel@gmail.com>
Subject: Re: [PATCH v3 4/6] spi: spi-axi-spi-engine: Add support for MOSI
 idle configuration
From: Nuno =?ISO-8859-1?Q?S=E1?= <noname.nuno@gmail.com>
To: Marcelo Schmitt <marcelo.schmitt1@gmail.com>, David Lechner
	 <dlechner@baylibre.com>
Cc: Marcelo Schmitt <marcelo.schmitt@analog.com>, broonie@kernel.org, 
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  nuno.sa@analog.com, linux-iio@vger.kernel.org, devicetree@vger.kernel.org,
  linux-spi@vger.kernel.org, linux-kernel@vger.kernel.org
Date: Fri, 07 Jun 2024 09:15:54 +0200
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On Thu, 2024-06-06 at 18:31 -0300, Marcelo Schmitt wrote:

...

>=20
>=20
>=20
> When is a driver version check needed?
> Yes, older versions of SPI-Engine won't support this, but the patch set s=
hould
> cause no regression. Even if loading the current ad4000 driver with
> older SPI-Engine HDL and driver, the ADC driver would get a warn (or erro=
r?)
> and do what's possible without MOSI idle feature (probably only be able t=
o do
> reg access) or fail probing.
>=20

Maybe I'm missing something but with the patchset we unconditionally set
SPI_MOSI_IDLE_HIGH. So if we load an hdl which does not support it things w=
ill
apparently be ok but it won't actually work, right? If I'm right we should =
have
a bit in a RO config_register telling us that the feature is being supporte=
d or
not. That way we only set the mode bit if we do support it...

- Nuno S=C3=A1