From mboxrd@z Thu Jan 1 00:00:00 1970 From: Adrian Hunter Subject: Re: [PATCH v2 1/3] mmc: sdhci-of-arasan: Add DTS property to disable DCMDs. Date: Fri, 8 Mar 2019 14:47:19 +0200 Message-ID: <9136f429-251a-87d3-8d6e-bf07c6882c8a@intel.com> References: <20190307084329.25416-1-christoph.muellner@theobroma-systems.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20190307084329.25416-1-christoph.muellner@theobroma-systems.com> Content-Language: en-US Sender: linux-kernel-owner@vger.kernel.org To: Christoph Muellner , robh+dt@kernel.org, mark.rutland@arm.com, heiko@sntech.de, shawn.lin@rock-chips.com, ulf.hansson@linaro.org Cc: Philipp Tomsich , Michal Simek , Douglas Anderson , Enric Balletbo i Serra , Viresh Kumar , Emil Renner Berthing , Lin Huang , Tony Xie , Randy Li , Vicente Bergas , Ezequiel Garcia , Klaus Goger , linux-mmc@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-rockchip@lists.infradead.org List-Id: devicetree@vger.kernel.org On 7/03/19 10:43 AM, Christoph Muellner wrote: > 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 suppress the feature activation, > by specifying the property disable-cqe-dcmd. > > Signed-off-by: Christoph Muellner > Signed-off-by: Philipp Tomsich Acked-by: Adrian Hunter > --- > 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); >