[PATCH 5.6 148/161] mmc: sdhci-msm: Clear tuning done flag while hs400 tuning

[Greg Kroah-Hartman]

From: Veerabhadrarao Badiganti <vbadigan@xxxxxxxxxxxxxx>

commit 9253d71011c349d5f5cc0cebdf68b4a80811b92d upstream.

Clear tuning_done flag while executing tuning to ensure vendor
specific HS400 settings are applied properly when the controller
is re-initialized in HS400 mode.

Without this, re-initialization of the qcom SDHC in HS400 mode fails
while resuming the driver from runtime-suspend or system-suspend.

Fixes: ff06ce417828 ("mmc: sdhci-msm: Add HS400 platform support")
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Veerabhadrarao Badiganti <vbadigan@xxxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/1590678838-18099-1-git-send-email-vbadigan@xxxxxxxxxxxxxx
Signed-off-by: Ulf Hansson <ulf.hansson@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 drivers/mmc/host/sdhci-msm.c |    6 ++++++
 1 file changed, 6 insertions(+)

--- a/drivers/mmc/host/sdhci-msm.c
+++ b/drivers/mmc/host/sdhci-msm.c
@@ -1118,6 +1118,12 @@ static int sdhci_msm_execute_tuning(stru
 	msm_host->use_cdr = true;
 
 	/*
+	 * Clear tuning_done flag before tuning to ensure proper
+	 * HS400 settings.
+	 */
+	msm_host->tuning_done = 0;
+
+	/*
 	 * For HS400 tuning in HS200 timing requires:
 	 * - select MCLK/2 in VENDOR_SPEC
 	 * - program MCLK to 400MHz (or nearest supported) in GCC