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 <christoph.muellner@xxxxxxxxxxxxxxxxxxxxx> Signed-off-by: Philipp Tomsich <philipp.tomsich@xxxxxxxxxxxxxxxxxxxxx> --- 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); -- 2.11.0