tpm: Provide a generic means to override the chip returned timeouts

Some Atmel TPMs provide completely wrong timeouts from their
TPM_CAP_PROP_TIS_TIMEOUT query. This patch detects that and returns
new correct values via a DID/VID table in the TIS driver.

Tested on ARM using an AT97SC3204T FW version 37.16

Cc: <stable@vger.kernel.org>
[PHuewe: without this fix these 'broken' Atmel TPMs won't function on
older kernels]
Signed-off-by: "Berg, Christopher" <Christopher.Berg@atmel.com>
Signed-off-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
Signed-off-by: Peter Huewe <peterhuewe@gmx.de>

(cherry picked from commit 8e54caf4)
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>

drivers/char/tpm/tpm.c

@@ -577,6 +577,32 @@ int tpm_get_timeouts(struct tpm_chip *chip)
 		}
 	}
 
+	old_timeout[0] = be32_to_cpu(tpm_cmd.params.getcap_out.cap.timeout.a);
+	old_timeout[1] = be32_to_cpu(tpm_cmd.params.getcap_out.cap.timeout.b);
+	old_timeout[2] = be32_to_cpu(tpm_cmd.params.getcap_out.cap.timeout.c);
+	old_timeout[3] = be32_to_cpu(tpm_cmd.params.getcap_out.cap.timeout.d);
+	memcpy(new_timeout, old_timeout, sizeof(new_timeout));
+
+	/*
+	 * Provide ability for vendor overrides of timeout values in case
+	 * of misreporting.
+	 */
+	if (chip->vendor.update_timeouts != NULL)
+		chip->vendor.timeout_adjusted =
+			chip->vendor.update_timeouts(chip, new_timeout);
+
+	if (!chip->vendor.timeout_adjusted) {
+		/* Don't overwrite default if value is 0 */
+		if (new_timeout[0] != 0 && new_timeout[0] < 1000) {
+			int i;
+
+			/* timeouts in msec rather usec */
+			for (i = 0; i != ARRAY_SIZE(new_timeout); i++)
+				new_timeout[i] *= 1000;
+			chip->vendor.timeout_adjusted = true;
+		}
+	}
+
 	/* Report adjusted timeouts */
 	if (chip->vendor.timeout_adjusted) {
 		dev_info(chip->dev,