From b5d0ebc99bf5d0801a5ecbe958caa3d68b8eaee8 Mon Sep 17 00:00:00 2001 From: Enric Balletbo i Serra Date: Tue, 27 Jun 2017 12:27:24 +0200 Subject: tpm: do not suspend/resume if power stays on The suspend/resume behavior of the TPM can be controlled by setting "powered-while-suspended" in the DTS. This is useful for the cases when hardware does not power-off the TPM. Signed-off-by: Sonny Rao Signed-off-by: Enric Balletbo i Serra Reviewed-by: Jason Gunthorpe Reviewed-by: Jarkko Sakkinen Signed-off-by: Jarkko Sakkinen Signed-off-by: James Morris --- drivers/char/tpm/tpm-interface.c | 3 +++ drivers/char/tpm/tpm.h | 1 + drivers/char/tpm/tpm_of.c | 3 +++ 3 files changed, 7 insertions(+) (limited to 'drivers/char/tpm') diff --git a/drivers/char/tpm/tpm-interface.c b/drivers/char/tpm/tpm-interface.c index 3123a6e44687..fe597e6c55c4 100644 --- a/drivers/char/tpm/tpm-interface.c +++ b/drivers/char/tpm/tpm-interface.c @@ -1119,6 +1119,9 @@ int tpm_pm_suspend(struct device *dev) if (chip == NULL) return -ENODEV; + if (chip->flags & TPM_CHIP_FLAG_ALWAYS_POWERED) + return 0; + if (chip->flags & TPM_CHIP_FLAG_TPM2) { tpm2_shutdown(chip, TPM2_SU_STATE); return 0; diff --git a/drivers/char/tpm/tpm.h b/drivers/char/tpm/tpm.h index 71d661a60df2..04fbff2edbf3 100644 --- a/drivers/char/tpm/tpm.h +++ b/drivers/char/tpm/tpm.h @@ -174,6 +174,7 @@ enum tpm_chip_flags { TPM_CHIP_FLAG_IRQ = BIT(2), TPM_CHIP_FLAG_VIRTUAL = BIT(3), TPM_CHIP_FLAG_HAVE_TIMEOUTS = BIT(4), + TPM_CHIP_FLAG_ALWAYS_POWERED = BIT(5), }; struct tpm_bios_log { diff --git a/drivers/char/tpm/tpm_of.c b/drivers/char/tpm/tpm_of.c index de57d4ac8901..aadb7f464076 100644 --- a/drivers/char/tpm/tpm_of.c +++ b/drivers/char/tpm/tpm_of.c @@ -36,6 +36,9 @@ int tpm_read_log_of(struct tpm_chip *chip) else return -ENODEV; + if (of_property_read_bool(np, "powered-while-suspended")) + chip->flags |= TPM_CHIP_FLAG_ALWAYS_POWERED; + sizep = of_get_property(np, "linux,sml-size", NULL); basep = of_get_property(np, "linux,sml-base", NULL); if (sizep == NULL && basep == NULL) -- cgit v1.2.3