[PATCH 4.19 19/44] mmc: sdhci-omap: Fix DCRC error handling during tuning

[Greg Kroah-Hartman]

4.19-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Faiz Abbas <faiz_abbas@xxxxxx>

commit db2039fcfd5754d15986340152e4503737f68f8d upstream.

Commit 7d33c3581536 ("mmc: sdhci-omap: Workaround for Errata i802")
disabled DCRC interrupts during tuning. This write to the interrupt
enable register gets overwritten in sdhci_prepare_data() and the
interrupt is not in fact disabled. Fix this by disabling the interrupt
in the host->ier variable.

Fixes: 7d33c3581536 ("mmc: sdhci-omap: Workaround for Errata i802")
Cc: <stable@xxxxxxxxxxxxxxx>
Signed-off-by: Faiz Abbas <faiz_abbas@xxxxxx>
Acked-by: Adrian Hunter <adrian.hunter@xxxxxxxxx>
Signed-off-by: Ulf Hansson <ulf.hansson@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 drivers/mmc/host/sdhci-omap.c |   12 ++++++++----
 1 file changed, 8 insertions(+), 4 deletions(-)

--- a/drivers/mmc/host/sdhci-omap.c
+++ b/drivers/mmc/host/sdhci-omap.c
@@ -288,9 +288,9 @@ static int sdhci_omap_execute_tuning(str
 	struct device *dev = omap_host->dev;
 	struct mmc_ios *ios = &mmc->ios;
 	u32 start_window = 0, max_window = 0;
+	bool dcrc_was_enabled = false;
 	u8 cur_match, prev_match = 0;
 	u32 length = 0, max_len = 0;
-	u32 ier = host->ier;
 	u32 phase_delay = 0;
 	int ret = 0;
 	u32 reg;
@@ -317,9 +317,10 @@ static int sdhci_omap_execute_tuning(str
 	 * during the tuning procedure. So disable it during the
 	 * tuning procedure.
 	 */
-	ier &= ~SDHCI_INT_DATA_CRC;
-	sdhci_writel(host, ier, SDHCI_INT_ENABLE);
-	sdhci_writel(host, ier, SDHCI_SIGNAL_ENABLE);
+	if (host->ier & SDHCI_INT_DATA_CRC) {
+		host->ier &= ~SDHCI_INT_DATA_CRC;
+		dcrc_was_enabled = true;
+	}
 
 	while (phase_delay <= MAX_PHASE_DELAY) {
 		sdhci_omap_set_dll(omap_host, phase_delay);
@@ -366,6 +367,9 @@ tuning_error:
 
 ret:
 	sdhci_reset(host, SDHCI_RESET_CMD | SDHCI_RESET_DATA);
+	/* Reenable forbidden interrupt */
+	if (dcrc_was_enabled)
+		host->ier |= SDHCI_INT_DATA_CRC;
 	sdhci_writel(host, host->ier, SDHCI_INT_ENABLE);
 	sdhci_writel(host, host->ier, SDHCI_SIGNAL_ENABLE);
 	return ret;