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authorEnric Balletbo i Serra <enric.balletbo@collabora.com>2017-06-27 12:27:24 +0200
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2018-06-13 16:15:27 +0200
commitc7d581820c86b2b2e8c6eaa38bddb76273a2ca28 (patch)
treec47807c9525726b1b131327ff6f2efa6c245a2b0 /drivers
parentdc45cafe612ec6960fe728f3260a0b751c73f4aa (diff)
tpm: do not suspend/resume if power stays on
commit b5d0ebc99bf5d0801a5ecbe958caa3d68b8eaee8 upstream. 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 <sonnyrao@chromium.org> Signed-off-by: Enric Balletbo i Serra <enric.balletbo@collabora.com> Reviewed-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com> Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> Signed-off-by: James Morris <james.l.morris@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers')
-rw-r--r--drivers/char/tpm/tpm-chip.c13
-rw-r--r--drivers/char/tpm/tpm-interface.c3
-rw-r--r--drivers/char/tpm/tpm.h1
3 files changed, 17 insertions, 0 deletions
diff --git a/drivers/char/tpm/tpm-chip.c b/drivers/char/tpm/tpm-chip.c
index a0d9ac6b6cc9..e759100e41a7 100644
--- a/drivers/char/tpm/tpm-chip.c
+++ b/drivers/char/tpm/tpm-chip.c
@@ -26,6 +26,7 @@
#include <linux/spinlock.h>
#include <linux/freezer.h>
#include <linux/major.h>
+#include <linux/of.h>
#include "tpm.h"
#include "tpm_eventlog.h"
@@ -324,8 +325,20 @@ static void tpm1_chip_unregister(struct tpm_chip *chip)
*/
int tpm_chip_register(struct tpm_chip *chip)
{
+#ifdef CONFIG_OF
+ struct device_node *np;
+#endif
int rc;
+#ifdef CONFIG_OF
+ np = of_find_node_by_name(NULL, "vtpm");
+ if (np) {
+ if (of_property_read_bool(np, "powered-while-suspended"))
+ chip->flags |= TPM_CHIP_FLAG_ALWAYS_POWERED;
+ }
+ of_node_put(np);
+#endif
+
rc = tpm1_chip_register(chip);
if (rc)
return rc;
diff --git a/drivers/char/tpm/tpm-interface.c b/drivers/char/tpm/tpm-interface.c
index 36afc1a21699..6ee3611d46cd 100644
--- a/drivers/char/tpm/tpm-interface.c
+++ b/drivers/char/tpm/tpm-interface.c
@@ -931,6 +931,9 @@ 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 772d99b3a8e4..36e1abda00f9 100644
--- a/drivers/char/tpm/tpm.h
+++ b/drivers/char/tpm/tpm.h
@@ -168,6 +168,7 @@ struct tpm_vendor_specific {
enum tpm_chip_flags {
TPM_CHIP_FLAG_REGISTERED = BIT(0),
TPM_CHIP_FLAG_TPM2 = BIT(1),
+ TPM_CHIP_FLAG_ALWAYS_POWERED = BIT(5),
};
struct tpm_chip {