[PATCH v2 1/4] mmc: sdhci: fix timing selection for 1-bit bus width

[ziniu . wang_1]

From: Luke Wang <ziniu.wang_1@xxxxxxx>

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.

Signed-off-by: Luke Wang <ziniu.wang_1@xxxxxxx>
---
 drivers/mmc/host/sdhci.c | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
index b1a3cd574c84..3e163f14a640 100644
--- a/drivers/mmc/host/sdhci.c
+++ b/drivers/mmc/host/sdhci.c
@@ -4539,8 +4539,14 @@ 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 | 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;
-- 
2.34.1