diff options
| author | Pavan Kunapuli <pkunapuli@nvidia.com> | 2012-04-09 19:31:50 +0530 |
|---|---|---|
| committer | Simone Willett <swillett@nvidia.com> | 2012-04-19 16:24:50 -0700 |
| commit | c5f2f507f0c26dffa94cb6ec5299c2d4da059214 (patch) | |
| tree | 79547572e6b4a81eeab34992738c74d1dddd0c8b /drivers/mmc/host | |
| parent | b31946b34507209f26c6d709e23fd1c0cedd25f8 (diff) | |
mmc: tegra: Disable card and host clk separately
Disable card clock before disabling internal clock to
ensure that there are no abnormal clock waveforms.
Bug 947058
Change-Id: I98a3f7f63b4380b62bead05f1018d3cddc0ac217
Signed-off-by: Pavan Kunapuli <pkunapuli@nvidia.com>
Reviewed-on: http://git-master/r/95396
Reviewed-by: Simone Willett <swillett@nvidia.com>
Tested-by: Simone Willett <swillett@nvidia.com>
Diffstat (limited to 'drivers/mmc/host')
| -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) |