[PATCH 2/4] mmc: sdhci: Avoid unnecessary re-configuration

[Adrian Hunter <adrian.hunter@intel.com>]

Avoid re-configuring UHS and preset settings when the settings have not
changed, irrespective of whether the clock is turning on.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
---
 drivers/mmc/host/sdhci.c | 8 ++------
 1 file changed, 2 insertions(+), 6 deletions(-)

diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
index 351b09b90d76..3675d69fb590 100644
--- a/drivers/mmc/host/sdhci.c
+++ b/drivers/mmc/host/sdhci.c
@@ -2304,7 +2304,6 @@ void sdhci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
 {
 	struct sdhci_host *host = mmc_priv(mmc);
 	bool reinit_uhs = host->reinit_uhs;
-	bool turning_on_clk = false;
 	u8 ctrl;
 
 	host->reinit_uhs = false;
@@ -2334,8 +2333,6 @@ void sdhci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
 		sdhci_enable_preset_value(host, false);
 
 	if (!ios->clock || ios->clock != host->clock) {
-		turning_on_clk = ios->clock && !host->clock;
-
 		host->ops->set_clock(host, ios->clock);
 		host->clock = ios->clock;
 
@@ -2363,11 +2360,10 @@ void sdhci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
 	host->ops->set_bus_width(host, ios->bus_width);
 
 	/*
-	 * Special case to avoid multiple clock changes during voltage
-	 * switching.
+	 * Avoid unnecessary changes. In particular, this avoids multiple clock
+	 * changes during voltage switching.
 	 */
 	if (!reinit_uhs &&
-	    turning_on_clk &&
 	    host->timing == ios->timing &&
 	    host->version >= SDHCI_SPEC_300 &&
 	    (host->preset_enabled || host->drv_type == ios->drv_type) &&
-- 
2.34.1