From: Alex Leibovich <alexl@xxxxxxxxxxx>
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 <alexl@xxxxxxxxxxx>
Signed-off-by: Marcin Wojtas <mw@xxxxxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
---
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
