summaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
-rw-r--r--drivers/mmc/host/sdhci.c27
1 files changed, 24 insertions, 3 deletions
diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
index 8072e16..409cde5 100644
--- a/drivers/mmc/host/sdhci.c
+++ b/drivers/mmc/host/sdhci.c
@@ -1243,13 +1243,12 @@ static void sdhci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
else
ctrl &= ~SDHCI_CTRL_HISPD;
- sdhci_writeb(host, ctrl, SDHCI_HOST_CONTROL);
-
if (host->version >= SDHCI_SPEC_300) {
u16 ctrl_2;
ctrl_2 = sdhci_readw(host, SDHCI_HOST_CONTROL2);
if (!(ctrl_2 & SDHCI_CTRL_PRESET_VAL_ENABLE)) {
+ sdhci_writeb(host, ctrl, SDHCI_HOST_CONTROL);
/*
* We only need to set Driver Strength if the
* preset value enable is not set.
@@ -1261,8 +1260,30 @@ static void sdhci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
ctrl_2 |= SDHCI_CTRL_DRV_TYPE_C;
sdhci_writew(host, ctrl_2, SDHCI_HOST_CONTROL2);
+ } else {
+ /*
+ * According to SDHC Spec v3.00, if the Preset Value
+ * Enable in the Host Control 2 register is set, we
+ * need to reset SD Clock Enable before changing High
+ * Speed Enable to avoid generating clock gliches.
+ */
+ u16 clk;
+ unsigned int clock;
+
+ /* Reset SD Clock Enable */
+ clk = sdhci_readw(host, SDHCI_CLOCK_CONTROL);
+ clk &= ~SDHCI_CLOCK_CARD_EN;
+ sdhci_writew(host, clk, SDHCI_CLOCK_CONTROL);
+
+ sdhci_writeb(host, ctrl, SDHCI_HOST_CONTROL);
+
+ /* Re-enable SD Clock */
+ clock = host->clock;
+ host->clock = 0;
+ sdhci_set_clock(host, clock);
}
- }
+ } else
+ sdhci_writeb(host, ctrl, SDHCI_HOST_CONTROL);
/*
* Some (ENE) controllers go apeshit on some ios operation,
OpenPOWER on IntegriCloud