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Diffstat (limited to 'drivers/mmc/host/sdhci-xenon.c')
| -rw-r--r-- | drivers/mmc/host/sdhci-xenon.c | 10 |
1 files changed, 10 insertions, 0 deletions
diff --git a/drivers/mmc/host/sdhci-xenon.c b/drivers/mmc/host/sdhci-xenon.c index 1dea1ba66f7b..4703cd540c7f 100644 --- a/drivers/mmc/host/sdhci-xenon.c +++ b/drivers/mmc/host/sdhci-xenon.c @@ -235,6 +235,16 @@ static void xenon_voltage_switch(struct sdhci_host *host) { /* Wait for 5ms after set 1.8V signal enable bit */ usleep_range(5000, 5500); + + /* + * For some reason the controller's Host Control2 register reports + * the bit representing 1.8V signaling as 0 when read after it was + * written as 1. Subsequent read reports 1. + * + * Since this may cause some issues, do an empty read of the Host + * Control2 register here to circumvent this. + */ + sdhci_readw(host, SDHCI_HOST_CONTROL2); } static const struct sdhci_ops sdhci_xenon_ops = { |