From 5e3486e64094c28a526543f1e8aa0d5964b7f02d Mon Sep 17 00:00:00 2001 From: Luke Wang Date: Wed, 11 Mar 2026 17:50:06 +0800 Subject: [PATCH] mmc: sdhci: fix timing selection for 1-bit bus width When 1-bit bus width is used with HS200/HS400 capabilities set, mmc_select_hs200() returns 0 without actually switching. This causes mmc_select_timing() to skip mmc_select_hs(), leaving eMMC in legacy mode (26MHz) instead of High Speed SDR (52MHz). Per JEDEC eMMC spec section 5.3.2, 1-bit mode supports High Speed SDR. Drop incompatible HS200/HS400/UHS/DDR caps early so timing selection falls through to mmc_select_hs() correctly. Fixes: f2119df6b764 ("mmc: sd: add support for signal voltage switch procedure") Signed-off-by: Luke Wang Acked-by: Adrian Hunter Cc: stable@vger.kernel.org Signed-off-by: Ulf Hansson --- drivers/mmc/host/sdhci.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c index ac7e11f37af7..fec9329e1edb 100644 --- a/drivers/mmc/host/sdhci.c +++ b/drivers/mmc/host/sdhci.c @@ -4532,8 +4532,15 @@ int sdhci_setup_host(struct sdhci_host *host) * their platform code before calling sdhci_add_host(), and we * won't assume 8-bit width for hosts without that CAP. */ - if (!(host->quirks & SDHCI_QUIRK_FORCE_1_BIT_DATA)) + if (host->quirks & SDHCI_QUIRK_FORCE_1_BIT_DATA) { + host->caps1 &= ~(SDHCI_SUPPORT_SDR104 | SDHCI_SUPPORT_SDR50 | SDHCI_SUPPORT_DDR50); + if (host->quirks2 & SDHCI_QUIRK2_CAPS_BIT63_FOR_HS400) + host->caps1 &= ~SDHCI_SUPPORT_HS400; + mmc->caps2 &= ~(MMC_CAP2_HS200 | MMC_CAP2_HS400 | MMC_CAP2_HS400_ES); + mmc->caps &= ~(MMC_CAP_DDR | MMC_CAP_UHS); + } else { mmc->caps |= MMC_CAP_4_BIT_DATA; + } if (host->quirks2 & SDHCI_QUIRK2_HOST_NO_CMD23) mmc->caps &= ~MMC_CAP_CMD23;