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tpm: Add a flag to indicate TPM power is managed by firmware

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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 <apronin@chromium.org>
Cc: Duncan Laurie <dlaurie@chromium.org>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Guenter Roeck <groeck@chromium.org>
Cc: Alexander Steffen <Alexander.Steffen@infineon.com>
Cc: Heiko Stuebner <heiko@sntech.de>
Tested-by: Heiko Stuebner <heiko@sntech.de>
Reviewed-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Stephen Boyd <swboyd@chromium.org>
Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
This commit is contained in:
Stephen Boyd 2019-09-20 11:32:36 -07:00 committed by Jarkko Sakkinen
parent fb8d6c8db3
commit 2e2ee5a2db
2 changed files with 8 additions and 1 deletions
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8
drivers/char/tpm/tpm-interface.c
View file

@ -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>
@ -394,7 +395,11 @@ 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)
@ -405,6 +410,7 @@ int tpm_pm_suspend(struct device *dev)
tpm_chip_stop(chip);
}
suspended:
return rc;
}
EXPORT_SYMBOL_GPL(tpm_pm_suspend);

1
drivers/char/tpm/tpm.h
View file

@ -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)