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References: <20201008225235.2035820-1-dianders@chromium.org> <20201008155154.2.I7b22281453b8a18ab16ef2bfd4c641fb1cc6a92c@changeid>
Subject: Re: [PATCH 2/3] Revert "i2c: i2c-qcom-geni: Fix DMA transfer race"
From:   Stephen Boyd <swboyd@chromium.org>
Cc:     linux-arm-msm@vger.kernel.org, linux-i2c@vger.kernel.org,
        Douglas Anderson <dianders@chromium.org>,
        Andy Gross <agross@kernel.org>,
        Mukesh Savaliya <msavaliy@codeaurora.org>,
        linux-kernel@vger.kernel.org
To:     Akash Asthana <akashast@codeaurora.org>,
        Bjorn Andersson <bjorn.andersson@linaro.org>,
        Douglas Anderson <dianders@chromium.org>,
        Wolfram Sang <wsa@kernel.org>
Date:   Fri, 09 Oct 2020 17:39:52 -0700
Message-ID: <160229039221.310579.11648298092136196056@swboyd.mtv.corp.google.com>
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Quoting Douglas Anderson (2020-10-08 15:52:34)
> This reverts commit 02b9aec59243c6240fc42884acc958602146ddf6.
>=20
> As talked about in the patch ("soc: qcom: geni: More properly switch
> to DMA mode"), swapping the order of geni_se_setup_m_cmd() and
> geni_se_xx_dma_prep() can sometimes cause corrupted transfers.  Thus
> we traded one problem for another.  Now that we've debugged the
> problem further and fixed the geni helper functions to more disable
> FIFO interrupts when we move to DMA mode we can revert it and end up
> with (hopefully) zero problems!
>=20
> To be explicit, the patch ("soc: qcom: geni: More properly switch
> to DMA mode") is a prerequisite for this one.
>=20
> Fixes: 02b9aec59243 ("i2c: i2c-qcom-geni: Fix DMA transfer race")
> Signed-off-by: Douglas Anderson <dianders@chromium.org>
> ---

Reviewed-by: Stephen Boyd <swboyd@chromium.org>