diff options
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/mmc/host/sdhci-tegra.c | 7 |
1 files changed, 7 insertions, 0 deletions
diff --git a/drivers/mmc/host/sdhci-tegra.c b/drivers/mmc/host/sdhci-tegra.c index af98cba88ecb..32e287987c69 100644 --- a/drivers/mmc/host/sdhci-tegra.c +++ b/drivers/mmc/host/sdhci-tegra.c @@ -405,6 +405,13 @@ static void tegra_3x_sdhci_set_card_clock(struct sdhci_host *sdhci, unsigned int if (clock && clock == sdhci->clock) return; + /* + * Disable the card clock before disabling the internal + * clock to avoid abnormal clock waveforms. + */ + clk = sdhci_readw(sdhci, SDHCI_CLOCK_CONTROL); + clk &= ~SDHCI_CLOCK_CARD_EN; + sdhci_writew(sdhci, clk, SDHCI_CLOCK_CONTROL); sdhci_writew(sdhci, 0, SDHCI_CLOCK_CONTROL); if (clock == 0) |