From 1a3ed0dc3594d99ff341ec63865a40519ea24b8d Mon Sep 17 00:00:00 2001
From: Alex Leibovich <alexl@marvell.com>
Date: Fri, 11 Dec 2020 15:16:56 +0100
Subject: [PATCH] mmc: sdhci-xenon: fix 1.8v regulator stabilization
Git-commit: 1a3ed0dc3594d99ff341ec63865a40519ea24b8d
Patch-mainline: v5.11-rc5
References: git-fixes
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 platforms 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@marvell.com>
Signed-off-by: Marcin Wojtas <mw@semihalf.com>
Cc: stable@vger.kernel.org
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Link: https://lore.kernel.org/r/20201211141656.24915-1-mw@semihalf.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Takashi Iwai <tiwai@suse.de>
---
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..d19eef5f725f 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 possible 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);
--
2.26.2