From: Alex Leibovich <[email protected]>

Automatic Clock Gating is a feature used for the power
consumption optimisation. It turned out that
during early init phase it may prevent the stable voltage
switch to 1.8V - due to that on some platfroms an endless
printout in dmesg can be observed:
"mmc1: 1.8V regulator output did not became stable"
Fix the problem by disabling the ACG at very beginning
of the sdhci_init and let that be enabled later.

Fixes: 3a3748dba881 ("mmc: sdhci-xenon: Add Marvell Xenon SDHC core 
functionality")
Signed-off-by: Alex Leibovich <[email protected]>
Signed-off-by: Marcin Wojtas <[email protected]>
Cc: [email protected]
---
 drivers/mmc/host/sdhci-xenon.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/drivers/mmc/host/sdhci-xenon.c b/drivers/mmc/host/sdhci-xenon.c
index c67611fdaa8a..4b05f6fdefb4 100644
--- a/drivers/mmc/host/sdhci-xenon.c
+++ b/drivers/mmc/host/sdhci-xenon.c
@@ -168,7 +168,12 @@ static void xenon_reset_exit(struct sdhci_host *host,
        /* Disable tuning request and auto-retuning again */
        xenon_retune_setup(host);
 
-       xenon_set_acg(host, true);
+       /*
+        * The ACG should be turned off at the early init time, in order
+        * to solve a possile issues with the 1.8V regulator stabilization.
+        * The feature is enabled in later stage.
+        */
+       xenon_set_acg(host, false);
 
        xenon_set_sdclk_off_idle(host, sdhc_id, false);
 
-- 
2.29.0

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