tpm, tpm_tis: Decorate tpm_get_timeouts() with request_locality()

commit a5665ec2affdba21bff3b0d4d3aed83b3951e8ff upstream.

This is shown with Samsung Chromebook Pro (Caroline) with TPM 1.2
(SLB 9670):

[    4.324298] TPM returned invalid status
[    4.324806] WARNING: CPU: 2 PID: 1 at drivers/char/tpm/tpm_tis_core.c:275 tpm_tis_status+0x86/0x8f

Background
==========

TCG PC Client Platform TPM Profile (PTP) Specification, paragraph 6.1 FIFO
Interface Locality Usage per Register, Table 39 Register Behavior Based on
Locality Setting for FIFO - a read attempt to TPM_STS_x Registers returns
0xFF in case of lack of locality.

The fix
=======

Decorate tpm_get_timeouts() with request_locality() and release_locality().

Fixes: a3fbfae82b4c ("tpm: take TPM chip power gating out of tpm_transmit()")
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: Laurent Bigonville <bigon@debian.org>
Cc: stable@vger.kernel.org
Reported-by: Lukasz Majczak <lma@semihalf.com>
Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Andrea Righi <andrea.righi@canonical.com>

diff --git a/drivers/char/tpm/tpm_tis_core.c b/drivers/char/tpm/tpm_tis_core.c
index ce80e7a2d42098f6a05802c32d187ec479956d76..a2e0395cbe618d8a86604c854a0e46dccca40be3 100644 (file)
--- a/drivers/char/tpm/tpm_tis_core.c
+++ b/drivers/char/tpm/tpm_tis_core.c
@@ -1029,11 +1029,21 @@ int tpm_tis_core_init(struct device *dev, struct tpm_tis_data *priv, int irq,
        init_waitqueue_head(&priv->read_queue);
        init_waitqueue_head(&priv->int_queue);
        if (irq != -1) {
-               /* Before doing irq testing issue a command to the TPM in polling mode
+               /*
+                * Before doing irq testing issue a command to the TPM in polling mode
                 * to make sure it works. May as well use that command to set the
                 * proper timeouts for the driver.
                 */
-               if (tpm_get_timeouts(chip)) {
+
+               rc = request_locality(chip, 0);
+               if (rc < 0)
+                       goto out_err;
+
+               rc = tpm_get_timeouts(chip);
+
+               release_locality(chip, 0);
+
+               if (rc) {
                        dev_err(dev, "Could not get TPM timeouts and durations\n");
                        rc = -ENODEV;
                        goto out_err;