From: Sonny Rao <sonny...@chromium.org> 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 <sonny...@chromium.org> Signed-off-by: Enric Balletbo i Serra <enric.balle...@collabora.com> --- Changes since v1: Jason Gunthorpe : - Move the code to handle suspend/resume in the common chip code. Documentation/devicetree/bindings/security/tpm/tpm-i2c.txt | 6 ++++++ drivers/char/tpm/tpm-interface.c | 3 +++ drivers/char/tpm/tpm.h | 3 +++ drivers/char/tpm/tpm_of.c | 3 +++ 4 files changed, 15 insertions(+) diff --git a/Documentation/devicetree/bindings/security/tpm/tpm-i2c.txt b/Documentation/devicetree/bindings/security/tpm/tpm-i2c.txt index 8cb638b..85c8216 100644 --- a/Documentation/devicetree/bindings/security/tpm/tpm-i2c.txt +++ b/Documentation/devicetree/bindings/security/tpm/tpm-i2c.txt @@ -8,6 +8,12 @@ Required properties: the firmware event log - linux,sml-size : size of the memory allocated for the firmware event log +Optional properties: + +- powered-while-suspended: present when the TPM is left powered on between + suspend and resume (makes the suspend/resume + callbacks do nothing). + Example (for OpenPower Systems with Nuvoton TPM 2.0 on I2C) ---------------------------------------------------------- diff --git a/drivers/char/tpm/tpm-interface.c b/drivers/char/tpm/tpm-interface.c index a2688ac..7f60780 100644 --- a/drivers/char/tpm/tpm-interface.c +++ b/drivers/char/tpm/tpm-interface.c @@ -944,6 +944,9 @@ int tpm_pm_suspend(struct device *dev) if (chip == NULL) return -ENODEV; + if (chip->powered_while_suspended) + 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 1ae9768..c8f796c 100644 --- a/drivers/char/tpm/tpm.h +++ b/drivers/char/tpm/tpm.h @@ -183,10 +183,13 @@ struct tpm_chip { unsigned long duration[3]; /* jiffies */ bool duration_adjusted; + bool powered_while_suspended; + struct dentry *bios_dir[TPM_NUM_EVENT_LOG_FILES]; const struct attribute_group *groups[3]; unsigned int groups_cnt; + #ifdef CONFIG_ACPI acpi_handle acpi_dev_handle; char ppi_version[TPM_PPI_VERSION_LEN + 1]; diff --git a/drivers/char/tpm/tpm_of.c b/drivers/char/tpm/tpm_of.c index 7dee42d7..33eddd4 100644 --- a/drivers/char/tpm/tpm_of.c +++ b/drivers/char/tpm/tpm_of.c @@ -34,6 +34,9 @@ int tpm_read_log_of(struct tpm_chip *chip) else return -ENODEV; + chip->powered_while_suspended = of_property_read_bool(np, + "powered-while-suspended"); + sizep = of_get_property(np, "linux,sml-size", NULL); basep = of_get_property(np, "linux,sml-base", NULL); if (sizep == NULL && basep == NULL) -- 2.9.3