Revert "mmc: sdhci-xenon: fix annoying 1.8V regulator warning"

This reverts commit bb32e19.

Commit 1a3ed0d ("mmc: sdhci-xenon: fix 1.8v regulator stabilization")
contains proper fix for the issue described in commit bb32e19 ("mmc:
sdhci-xenon: fix annoying 1.8V regulator warning").

Fixes: 8d876bf ("mmc: sdhci-xenon: wait 5ms after set 1.8V signal enable")
Cc: stable@vger.kernel.org # 1a3ed0d ("mmc: sdhci-xenon: fix 1.8v regulator stabilization")
Signed-off-by: Pali Rohár <pali@kernel.org>
Reviewed-by: Marek Behún <kabel@kernel.org>
Reviewed-by: Marcin Wojtas <mw@semihalf.com>
Link: https://lore.kernel.org/r/20220318141441.32329-1-pali@kernel.org
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

Author: pali

drivers/mmc/host/sdhci-xenon.c

@@ -241,16 +241,6 @@ static void xenon_voltage_switch(struct sdhci_host *host)
 {
 	/* Wait for 5ms after set 1.8V signal enable bit */
 	usleep_range(5000, 5500);
-
-	/*
-	 * For some reason the controller's Host Control2 register reports
-	 * the bit representing 1.8V signaling as 0 when read after it was
-	 * written as 1. Subsequent read reports 1.
-	 *
-	 * Since this may cause some issues, do an empty read of the Host
-	 * Control2 register here to circumvent this.
-	 */
-	sdhci_readw(host, SDHCI_HOST_CONTROL2);
 }
 
 static unsigned int xenon_get_max_clock(struct sdhci_host *host)