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Subject: Re: [PATCH 03/10] spi: Add flag for no TX after a RX in the same Chip
 Select
To:     Mark Brown <broonie@kernel.org>
CC:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        "Rafael J . Wysocki" <rafael@kernel.org>,
        Sanjay R Mehta <sanju.mehta@amd.com>,
        Nehal Bakulchandra Shah <Nehal-Bakulchandra.shah@amd.com>,
        <linux-kernel@vger.kernel.org>, <linux-spi@vger.kernel.org>,
        <patches@opensource.cirrus.com>
References: <20210908113450.788452-1-tanureal@opensource.cirrus.com>
 <20210908113450.788452-4-tanureal@opensource.cirrus.com>
 <20210908123734.GF4112@sirena.org.uk>
From:   Lucas tanure <tanureal@opensource.cirrus.com>
Message-ID: <7dc20785-95da-6599-49dc-8e5f805d6a14@opensource.cirrus.com>
Date:   Thu, 9 Sep 2021 11:51:21 +0100
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On 9/8/21 1:37 PM, Mark Brown wrote:
> On Wed, Sep 08, 2021 at 12:34:44PM +0100, Lucas Tanure wrote:
>> Some controllers can't write to the bus after a read without
>> releasing the chip select, so add flag and a check in spi core
> 
> Nothing you've added ever reads this flag and I'm not sure what anything
> would be able to constructively do with it so why add the flag?  I don't
> understand what the use case is.
> 
__spi_validate checks this flag and makes sure the message can be 
received by the controller.
__spi_validate can't fix the message, so it only rejects the message.