]> git.baikalelectronics.ru Git - kernel.git/commit
mmc: sdhci: Fix voltage switch delay
authorAdrian Hunter <adrian.hunter@intel.com>
Mon, 28 Nov 2022 13:32:56 +0000 (15:32 +0200)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Thu, 8 Dec 2022 10:23:06 +0000 (11:23 +0100)
commitcce752c426ec73c766f2e17c8b8e5143097ea364
treee11f3918cbba7e81b5238d1bbdc409119286c0c4
parent196aa40fe86d606958861689d900eb8dcd7230cf
mmc: sdhci: Fix voltage switch delay

commit 0bb92af50ff1c3e1d18d0e76b1eefcf9cd5c9162 upstream.

Commit 82084e395282 ("mmc: sdhci: update signal voltage switch code")
removed voltage switch delays from sdhci because mmc core had been
enhanced to support them. However that assumed that sdhci_set_ios()
did a single clock change, which it did not, and so the delays in mmc
core, which should have come after the first clock change, were not
effective.

Fix by avoiding re-configuring UHS and preset settings when the clock
is turning on and the settings have not changed. That then also avoids
the associated clock changes, so that then sdhci_set_ios() does a single
clock change when voltage switching, and the mmc core delays become
effective.

To do that has meant keeping track of driver strength (host->drv_type),
and cases of reinitialization (host->reinit_uhs).

Note also, the 'turning_on_clk' restriction should not be necessary
but is done to minimize the impact of the change on stable kernels.

Fixes: 82084e395282 ("mmc: sdhci: update signal voltage switch code")
Cc: stable@vger.kernel.org
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Link: https://lore.kernel.org/r/20221128133259.38305-2-adrian.hunter@intel.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/mmc/host/sdhci.c
drivers/mmc/host/sdhci.h