TPM: Export wait_for_stat for other vendor specific drivers

Moved wait_for_stat to tpm.c so that other drivers can use it.
Also renamed it to avoid future namespace conflicts.

Signed-off-by: Rajiv Andrade <srajiv@linux.vnet.ibm.com>

1 files changed, 41 insertions, 0 deletions

diff --git a/drivers/char/tpm/tpm.c b/drivers/char/tpm/tpm.c
index 2e12b3f9813..efd24bbb5cb 100644
--- a/drivers/char/tpm/tpm.c
+++ b/drivers/char/tpm/tpm.c
@@ -27,6 +27,7 @@
 #include <linux/slab.h>
 #include <linux/mutex.h>
 #include <linux/spinlock.h>
+#include <linux/freezer.h>
 
 #include "tpm.h"
 
@@ -1057,6 +1058,46 @@ ssize_t tpm_store_cancel(struct device *dev, struct device_attribute *attr,
 }
 EXPORT_SYMBOL_GPL(tpm_store_cancel);
 
+int wait_for_tpm_stat(struct tpm_chip *chip, u8 mask, unsigned long timeout,
+			 wait_queue_head_t *queue)
+{
+	unsigned long stop;
+	long rc;
+	u8 status;
+
+	/* check current status */
+	status = chip->vendor.status(chip);
+	if ((status & mask) == mask)
+		return 0;
+
+	stop = jiffies + timeout;
+
+	if (chip->vendor.irq) {
+again:
+		timeout = stop - jiffies;
+		if ((long)timeout <= 0)
+			return -ETIME;
+		rc = wait_event_interruptible_timeout(*queue,
+						      ((chip->vendor.status(chip)
+						      & mask) == mask),
+						      timeout);
+		if (rc > 0)
+			return 0;
+		if (rc == -ERESTARTSYS && freezing(current)) {
+			clear_thread_flag(TIF_SIGPENDING);
+			goto again;
+		}
+	} else {
+		do {
+			msleep(TPM_TIMEOUT);
+			status = chip->vendor.status(chip);
+			if ((status & mask) == mask)
+				return 0;
+		} while (time_before(jiffies, stop));
+	}
+	return -ETIME;
+}
+EXPORT_SYMBOL_GPL(wait_for_tpm_stat);
 /*
  * Device file system interface to the TPM
  *