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Date:   Mon, 2 Jul 2018 20:24:34 +0200
From:   Wolfram Sang <wsa@the-dreams.de>
To:     Eddie James <eajames@linux.vnet.ibm.com>
Cc:     linux-i2c@vger.kernel.org, linux-kernel@vger.kernel.org,
        devicetree@vger.kernel.org, robh+dt@kernel.org,
        benh@kernel.crashing.org, joel@jms.id.au, mark.rutland@arm.com,
        gregkh@linuxfoundation.org, rdunlap@infradead.org,
        andy.shevchenko@gmail.com, peda@axentia.se
Subject: Re: [PATCH v10 5/7] i2c: fsi: Add transfer implementation
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> > > +	if (msg->flags & I2C_M_RD)
> > > +		cmd |=3D I2C_CMD_READ;
> > Since you support MANGLING, I'd think you can easily support
> > I2C_M_REV_DIR_ADDR here, too?
>=20
> Hm, I don't really understand the purpose of that flag. From the docs:
>=20
> This toggles the Rd/Wr flag. That is, if you want to do a write, but
> =C2=A0=C2=A0=C2=A0 need to emit an Rd instead of a Wr, or vice versa, you=
 set this
> =C2=A0=C2=A0=C2=A0 flag. For example:
> S Addr Rd [A] Data [A] Data [A] ... [A] Data [A] P
>=20
> I don't think our hardware supports this type of operation.

I'd think something like this should do:

	if (msg->flags & I2C_M_REV_DIR_ADDR)
		cmd ^=3D I2C_CMD_READ;


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