Patch suggested by Dong Aisheng <donga...@gmail.com>, this avoids
additional clock start/stop cycles during the transition to 1.8V
signalling mode.

Signed-off-by: Russell King <rmk+ker...@arm.linux.org.uk>
---
 drivers/mmc/host/sdhci.c | 12 ------------
 1 file changed, 12 deletions(-)

diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
index 748333ba6e96..0bcef2d42da4 100644
--- a/drivers/mmc/host/sdhci.c
+++ b/drivers/mmc/host/sdhci.c
@@ -1507,12 +1507,6 @@ static void sdhci_do_set_ios(struct sdhci_host *host, 
struct mmc_ios *ios)
                        host->ops->set_clock(host, host->clock);
                }
 
-
-               /* Reset SD Clock Enable */
-               clk = sdhci_readw(host, SDHCI_CLOCK_CONTROL);
-               clk &= ~SDHCI_CLOCK_CARD_EN;
-               sdhci_writew(host, clk, SDHCI_CLOCK_CONTROL);
-
                if (host->ops->set_uhs_signaling)
                        host->ops->set_uhs_signaling(host, ios->timing);
                else {
@@ -1546,9 +1540,6 @@ static void sdhci_do_set_ios(struct sdhci_host *host, 
struct mmc_ios *ios)
                        ios->drv_type = (preset & SDHCI_PRESET_DRV_MASK)
                                >> SDHCI_PRESET_DRV_SHIFT;
                }
-
-               /* Re-enable SD Clock */
-               host->ops->set_clock(host, host->clock);
        } else
                sdhci_writeb(host, ctrl, SDHCI_HOST_CONTROL);
 
@@ -1757,9 +1748,6 @@ static int sdhci_do_start_signal_voltage_switch(struct 
sdhci_host *host,
                ctrl |= SDHCI_CTRL_VDD_180;
                sdhci_writew(host, ctrl, SDHCI_HOST_CONTROL2);
 
-               /* Wait for 5ms */
-               usleep_range(5000, 5500);
-
                /* 1.8V regulator output should be stable within 5 ms */
                ctrl = sdhci_readw(host, SDHCI_HOST_CONTROL2);
                if (ctrl & SDHCI_CTRL_VDD_180)
-- 
1.8.3.1

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