mmc: sdhci: fix timing selection for 1-bit bus width

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commit 5e3486e640 upstream.

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: f2119df6b7 ("mmc: sd: add support for signal voltage switch procedure")
Signed-off-by: Luke Wang <ziniu.wang_1@nxp.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: stable@vger.kernel.org
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

...

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Luke Wang 2026-03-11 17:50:06 +08:00 • committed by Greg Kroah-Hartman

parent a45eedccce

commit cb301583f4

1 changed files with 8 additions and 1 deletions

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drivers/mmc/host/sdhci.c

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