[PATCH] mmc: dw_mmc: avoid long timeout if register invalid

From: Christian Löhle
Date: Fri Sep 17 2021 - 03:51:18 EST



Set the limit to 1s if the register is at reset value.

Signed-off-by: Christian Loehle <cloehle@xxxxxxxxxxxxxx>
---
drivers/mmc/host/dw_mmc.c | 8 ++++++++
1 file changed, 8 insertions(+)

diff --git a/drivers/mmc/host/dw_mmc.c b/drivers/mmc/host/dw_mmc.c
index 6578cc64ae9e..cd9a6e0a7449 100644
--- a/drivers/mmc/host/dw_mmc.c
+++ b/drivers/mmc/host/dw_mmc.c
@@ -1983,6 +1983,14 @@ static void dw_mci_set_drto(struct dw_mci *host)
/* add a bit spare time */
drto_ms += 10;

+ /*
+ * If TMOUT register still holds the reset value the above calculation
+ * would yield a timeout of over 167 seconds, limit it to 1000ms.
+ * Normal reads/writes should not take anywhere close to 120s.
+ */
+ if (drto_ms > 120000)
+ drto_ms = 1000;
+
spin_lock_irqsave(&host->irq_lock, irqflags);
if (!test_bit(EVENT_DATA_COMPLETE, &host->pending_events))
mod_timer(&host->dto_timer,
--
2.32.0
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