1 files changed, 42 insertions, 5 deletions

diff --git a/drivers/char/tpm/tpm-interface.c b/drivers/char/tpm/tpm-interface.c
index f62f7871edbd..8d18b33aa62d 100644
--- a/drivers/char/tpm/tpm-interface.c
+++ b/drivers/char/tpm/tpm-interface.c
@@ -58,6 +58,37 @@ unsigned long tpm_calc_ordinal_duration(struct tpm_chip *chip, u32 ordinal)
 }
 EXPORT_SYMBOL_GPL(tpm_calc_ordinal_duration);
 
+static void tpm_chip_cancel(struct tpm_chip *chip)
+{
+	if (!chip->ops->cancel)
+		return;
+
+	chip->ops->cancel(chip);
+}
+
+static u8 tpm_chip_status(struct tpm_chip *chip)
+{
+	if (!chip->ops->status)
+		return 0;
+
+	return chip->ops->status(chip);
+}
+
+static bool tpm_chip_req_canceled(struct tpm_chip *chip, u8 status)
+{
+	if (!chip->ops->req_canceled)
+		return false;
+
+	return chip->ops->req_canceled(chip, status);
+}
+
+static bool tpm_transmit_completed(u8 status, struct tpm_chip *chip)
+{
+	u8 status_masked = status & chip->ops->req_complete_mask;
+
+	return status_masked == chip->ops->req_complete_val;
+}
+
 static ssize_t tpm_try_transmit(struct tpm_chip *chip, void *buf, size_t bufsiz)
 {
 	struct tpm_header *header = buf;
@@ -104,12 +135,11 @@ static ssize_t tpm_try_transmit(struct tpm_chip *chip, void *buf, size_t bufsiz)
 
 	stop = jiffies + tpm_calc_ordinal_duration(chip, ordinal);
 	do {
-		u8 status = chip->ops->status(chip);
-		if ((status & chip->ops->req_complete_mask) ==
-		    chip->ops->req_complete_val)
+		u8 status = tpm_chip_status(chip);
+		if (tpm_transmit_completed(status, chip))
 			goto out_recv;
 
-		if (chip->ops->req_canceled(chip, status)) {
+		if (tpm_chip_req_canceled(chip, status)) {
 			dev_err(&chip->dev, "Operation Canceled\n");
 			return -ECANCELED;
 		}
@@ -118,7 +148,14 @@ static ssize_t tpm_try_transmit(struct tpm_chip *chip, void *buf, size_t bufsiz)
 		rmb();
 	} while (time_before(jiffies, stop));
 
-	chip->ops->cancel(chip);
+	/*
+	 * Check for completion one more time, just in case the device reported
+	 * it while the driver was sleeping in the busy loop above.
+	 */
+	if (tpm_transmit_completed(tpm_chip_status(chip), chip))
+		goto out_recv;
+
+	tpm_chip_cancel(chip);
 	dev_err(&chip->dev, "Operation Timed out\n");
 	return -ETIME;