Commit d53a6adf authored by Lukasz Majczak's avatar Lukasz Majczak Committed by Jarkko Sakkinen
Browse files

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



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_tis_gen_interrupt() with request_locality() and
release_locality().

Cc: Laurent Bigonville <bigon@debian.org>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: stable@vger.kernel.org
Fixes: a3fbfae8 ("tpm: take TPM chip power gating out of tpm_transmit()")
Signed-off-by: default avatarLukasz Majczak <lma@semihalf.com>
Signed-off-by: default avatarJarkko Sakkinen <jarkko@kernel.org>
parent a5665ec2

drivers/char/tpm/tpm_tis_core.c

+13 −3
Original line number Diff line number Diff line
@@ -707,12 +707,22 @@ static int tpm_tis_gen_interrupt(struct tpm_chip *chip) 
	const char *desc = "attempting to generate an interrupt";

	u32 cap2;

	cap_t cap;

	int ret;



	/* TPM 2.0 */

	if (chip->flags & TPM_CHIP_FLAG_TPM2)

		return tpm2_get_tpm_pt(chip, 0x100, &cap2, desc);

	else

		return tpm1_getcap(chip, TPM_CAP_PROP_TIS_TIMEOUT, &cap, desc,

				  0);



	/* TPM 1.2 */

	ret = request_locality(chip, 0);

	if (ret < 0)

		return ret;



	ret = tpm1_getcap(chip, TPM_CAP_PROP_TIS_TIMEOUT, &cap, desc, 0);



	release_locality(chip, 0);



	return ret;

}



/* Register the IRQ and issue a command that will cause an interrupt. If an