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Message-ID: <0e18b3aa83a62103b0f06ee516193c03f80abae9.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: David Lechner <dlechner@baylibre.com>, Marcelo Schmitt
 <marcelo.schmitt@analog.com>, broonie@kernel.org, lars@metafoo.de, 
 Michael.Hennerich@analog.com, jic23@kernel.org, robh+dt@kernel.org, 
 krzysztof.kozlowski+dt@linaro.org, conor+dt@kernel.org, nuno.sa@analog.com,
  marcelo.schmitt1@gmail.com
Cc: linux-iio@vger.kernel.org, devicetree@vger.kernel.org, 
	linux-spi@vger.kernel.org, linux-kernel@vger.kernel.org
Date: Thu, 06 Jun 2024 08:51:29 +0200
In-Reply-To: <ed4fe3de-726b-4eba-a12a-d2f7b1da26d1@baylibre.com>
References: <cover.1717539384.git.marcelo.schmitt@analog.com>
	 <a6b00e84325bbe44919cc49509e837f2555367d0.1717539384.git.marcelo.schmitt@analog.com>
	 <ed4fe3de-726b-4eba-a12a-d2f7b1da26d1@baylibre.com>
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On Wed, 2024-06-05 at 12:03 -0500, David Lechner wrote:
> On 6/4/24 5:43 PM, Marcelo Schmitt wrote:
> > Implement MOSI idle low and MOSI idle high to better support peripheral=
s
> > that request specific MOSI behavior.
> >=20
> > Signed-off-by: Marcelo Schmitt <marcelo.schmitt@analog.com>
> > ---
> > =C2=A0drivers/spi/spi-axi-spi-engine.c | 8 +++++++-
> > =C2=A01 file changed, 7 insertions(+), 1 deletion(-)
> >=20
> > diff --git a/drivers/spi/spi-axi-spi-engine.c b/drivers/spi/spi-axi-spi=
-
> > engine.c
> > index 0aa31d745734..549f03069d0e 100644
> > --- a/drivers/spi/spi-axi-spi-engine.c
> > +++ b/drivers/spi/spi-axi-spi-engine.c
> > @@ -41,6 +41,7 @@
> > =C2=A0#define SPI_ENGINE_CONFIG_CPHA			BIT(0)
> > =C2=A0#define SPI_ENGINE_CONFIG_CPOL			BIT(1)
> > =C2=A0#define SPI_ENGINE_CONFIG_3WIRE			BIT(2)
> > +#define SPI_ENGINE_CONFIG_SDO_IDLE		BIT(3)
> > =C2=A0
> > =C2=A0#define SPI_ENGINE_INST_TRANSFER		0x0
> > =C2=A0#define SPI_ENGINE_INST_ASSERT			0x1
> > @@ -132,6 +133,10 @@ static unsigned int spi_engine_get_config(struct
> > spi_device *spi)
> > =C2=A0		config |=3D SPI_ENGINE_CONFIG_CPHA;
> > =C2=A0	if (spi->mode & SPI_3WIRE)
> > =C2=A0		config |=3D SPI_ENGINE_CONFIG_3WIRE;
> > +	if (spi->mode & SPI_MOSI_IDLE_HIGH)
> > +		config |=3D SPI_ENGINE_CONFIG_SDO_IDLE;
> > +	if (spi->mode & SPI_MOSI_IDLE_LOW)
> > +		config &=3D ~SPI_ENGINE_CONFIG_SDO_IDLE;
> > =C2=A0
> > =C2=A0	return config;
> > =C2=A0}
> > @@ -645,7 +650,8 @@ static int spi_engine_probe(struct platform_device
> > *pdev)
> > =C2=A0		return ret;
> > =C2=A0
> > =C2=A0	host->dev.of_node =3D pdev->dev.of_node;
> > -	host->mode_bits =3D SPI_CPOL | SPI_CPHA | SPI_3WIRE;
> > +	host->mode_bits =3D SPI_CPOL | SPI_CPHA | SPI_3WIRE |
> > SPI_MOSI_IDLE_LOW
> > +			=C2=A0 | SPI_MOSI_IDLE_HIGH;
> > =C2=A0	host->bits_per_word_mask =3D SPI_BPW_RANGE_MASK(1, 32);
> > =C2=A0	host->max_speed_hz =3D clk_get_rate(spi_engine->ref_clk) / 2;
> > =C2=A0	host->transfer_one_message =3D spi_engine_transfer_one_message;
>=20
> I think we need a version check instead of setting the flags unconditiona=
lly
> here since older versions of the AXI SPI Engine won't support this featur=
e.

Oh, was not aware of that... Then, we definitely need to do that. Marcelo, =
only
add my r-b tag with the version change in place.

- Nuno S=C3=A1