Messages in this thread Patch in this message | | | From | Ben Chuang <> | Subject | [RFC PATCH V3 13/21] mmc: sdhci: UHS-II support, skip signal_voltage_switch() | Date | Fri, 10 Jul 2020 19:11:04 +0800 |
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From: AKASHI Takahiro <takahiro.akashi@linaro.org>
sdhci_start_signal_voltage_switch() should be called only in UHS-I mode, and not for UHS-II mode.
Signed-off-by: Ben Chuang <ben.chuang@genesyslogic.com.tw> Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org> --- drivers/mmc/host/sdhci.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-)
diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c index 5511649946b9..7f2537648a08 100644 --- a/drivers/mmc/host/sdhci.c +++ b/drivers/mmc/host/sdhci.c @@ -2623,8 +2623,13 @@ int sdhci_start_signal_voltage_switch(struct mmc_host *mmc, /* * Signal Voltage Switching is only applicable for Host Controllers * v3.00 and above. + * But for UHS2, the signal voltage is supplied by vdd2 which is + * already 1.8v so no voltage switch required. */ - if (host->version < SDHCI_SPEC_300) + if (host->version < SDHCI_SPEC_300 || + (IS_ENABLED(CONFIG_MMC_SDHCI_UHS2) && + host->version >= SDHCI_SPEC_400 && + host->mmc->flags & MMC_UHS2_SUPPORT)) return 0; ctrl = sdhci_readw(host, SDHCI_HOST_CONTROL2); -- 2.27.0
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