On some platforms, the TPM power is managed by firmware and therefore we
don't need to stop the TPM on suspend when going to a light version of
suspend such as S0ix ("freeze" suspend state). Add a chip flag,
TPM_CHIP_FLAG_FIRMWARE_POWER_MANAGED, to indicate this so that certain
platforms can probe for the usage of this light suspend and avoid
touching the TPM state across suspend/resume.Cc: Andrey Pronin <[email protected]> Cc: Duncan Laurie <[email protected]> Cc: Jason Gunthorpe <[email protected]> Cc: Arnd Bergmann <[email protected]> Cc: Greg Kroah-Hartman <[email protected]> Cc: Guenter Roeck <[email protected]> Cc: Alexander Steffen <[email protected]> Signed-off-by: Stephen Boyd <[email protected]> --- drivers/char/tpm/tpm-interface.c | 8 +++++++- drivers/char/tpm/tpm.h | 1 + 2 files changed, 8 insertions(+), 1 deletion(-) diff --git a/drivers/char/tpm/tpm-interface.c b/drivers/char/tpm/tpm-interface.c index 1b4f95c13e00..0b3def8e8186 100644 --- a/drivers/char/tpm/tpm-interface.c +++ b/drivers/char/tpm/tpm-interface.c @@ -23,6 +23,7 @@ #include <linux/slab.h> #include <linux/mutex.h> #include <linux/spinlock.h> +#include <linux/suspend.h> #include <linux/freezer.h> #include <linux/tpm_eventlog.h> @@ -395,7 +396,11 @@ int tpm_pm_suspend(struct device *dev) return -ENODEV; if (chip->flags & TPM_CHIP_FLAG_ALWAYS_POWERED) - return 0; + goto suspended; + + if ((chip->flags & TPM_CHIP_FLAG_FIRMWARE_POWER_MANAGED) && + !pm_suspend_via_firmware()) + goto suspended; if (!tpm_chip_start(chip)) { if (chip->flags & TPM_CHIP_FLAG_TPM2) @@ -406,6 +411,7 @@ int tpm_pm_suspend(struct device *dev) tpm_chip_stop(chip); } +suspended: return rc; } EXPORT_SYMBOL_GPL(tpm_pm_suspend); diff --git a/drivers/char/tpm/tpm.h b/drivers/char/tpm/tpm.h index e503ffc3aa39..28f73331aa2e 100644 --- a/drivers/char/tpm/tpm.h +++ b/drivers/char/tpm/tpm.h @@ -162,6 +162,7 @@ enum tpm_chip_flags { TPM_CHIP_FLAG_VIRTUAL = BIT(3), TPM_CHIP_FLAG_HAVE_TIMEOUTS = BIT(4), TPM_CHIP_FLAG_ALWAYS_POWERED = BIT(5), + TPM_CHIP_FLAG_FIRMWARE_POWER_MANAGED = BIT(6), }; #define to_tpm_chip(d) container_of(d, struct tpm_chip, dev) -- Sent by a computer through tubes
