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    SubjectRe: [PATCH 1/3] dt-bindings: mmc: Add DTS property to disable DCMDs on Arasan controllers
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    > On 01.03.2019, at 19:17, Heiko Stuebner <heiko@sntech.de> wrote:
    >
    > Am Freitag, 1. März 2019, 17:43:45 CET schrieb Christoph Muellner:
    >> Direct commands (DCMDs) are an optional feature of eMMC 5.1's command
    >> queue engine (CQE). The Arasan eMMC 5.1 controller uses the CQHCI,
    >> which exposes a control register bit to enable the feature.
    >> The current implementation sets this bit unconditionally.
    >>
    >> This patch allows to surpress the feature activation,
    >> by specifying the property disable-cqe-dcmd.
    >>
    >> Signed-off-by: Christoph Muellner <christoph.muellner@theobroma-systems.com>
    >> Signed-off-by: Philipp Tomsich <philipp.tomsich@theobroma-systems.com>
    >
    > Patch subject is needs improvement :-) .
    > I did scratch my head a lot regarding "where is the code change"
    > until I actually looked into the patch itself, so you probably want
    >
    > mmc: sdhci-of-arasan: Add DTS property to disable DCMDs
    >
    > or similar instead of "dt-bindings: ..." here to match the subsystem.

    Yes, I've spotted this as well after sending it.
    I've already renamed to "mmc: sdhci-of-arasan: Add DTS property to disable DCMDs." for v2.

    Thanks,
    Christoph

    >
    >
    > Heiko
    >
    >> ---
    >> drivers/mmc/host/sdhci-of-arasan.c | 5 ++++-
    >> 1 file changed, 4 insertions(+), 1 deletion(-)
    >>
    >> diff --git a/drivers/mmc/host/sdhci-of-arasan.c b/drivers/mmc/host/sdhci-of-arasan.c
    >> index c9e3e050ccc8..88dc3f00a5be 100644
    >> --- a/drivers/mmc/host/sdhci-of-arasan.c
    >> +++ b/drivers/mmc/host/sdhci-of-arasan.c
    >> @@ -832,7 +832,10 @@ static int sdhci_arasan_probe(struct platform_device *pdev)
    >> host->mmc_host_ops.start_signal_voltage_switch =
    >> sdhci_arasan_voltage_switch;
    >> sdhci_arasan->has_cqe = true;
    >> - host->mmc->caps2 |= MMC_CAP2_CQE | MMC_CAP2_CQE_DCMD;
    >> + host->mmc->caps2 |= MMC_CAP2_CQE;
    >> +
    >> + if (!of_property_read_bool(np, "disable-cqe-dcmd"))
    >> + host->mmc->caps2 |= MMC_CAP2_CQE_DCMD;
    >> }
    >>
    >> ret = sdhci_arasan_add_host(sdhci_arasan);
    >>
    >
    >
    >
    >

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