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mmc: tmio: bring tuning HW to a sane state with MMC_POWER_OFF

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When powering off a card, we need to disable the tuning HW (like SCC for
the Renesas SDHI) to get to a sane state and allow for re-tuning new
cards. This was hidden before because we wrongly did that in hw_reset()
before which was an unintended use of hw_reset(). Now that we corrected
the use of hw_reset() meanwhile, we revealed this shortcoming and need
to fix it properly by explicitly calling the downgrade callback.

Fixes: 6e7d4de10890 ("mmc: renesas_sdhi: move wrong 'hw_reset' to 'reset'")
Suggested-by: Takeshi Saito <takeshi.saito.xv@renesas.com>
Reviewed-by: Takeshi Saito <takeshi.saito.xv@renesas.com>
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Tested-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Reviewed-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Tested-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Link: https://lore.kernel.org/r/20201106072549.1495-3-wsa+renesas@sang-engineering.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
This commit is contained in:
Wolfram Sang 2020-11-06 08:25:48 +01:00 committed by Ulf Hansson
parent 1023e290ba
commit 24ce2d7b8b
1 changed files with 3 additions and 0 deletions
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3
drivers/mmc/host/tmio_mmc_core.c
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@ -927,6 +927,9 @@ static void tmio_mmc_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
switch (ios->power_mode) {
case MMC_POWER_OFF:
tmio_mmc_power_off(host);
/* Downgrade ensures a sane state for tuning HW (e.g. SCC) */
if (host->mmc->ops->hs400_downgrade)
host->mmc->ops->hs400_downgrade(host->mmc);
host->set_clock(host, 0);
break;
case MMC_POWER_UP: