4.4-stable review patch. If anyone has any objections, please let me know.
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From: Enric Balletbo i Serra enric.balletbo@collabora.com
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
--- drivers/char/tpm/tpm-chip.c | 13 +++++++++++++ drivers/char/tpm/tpm-interface.c | 3 +++ drivers/char/tpm/tpm.h | 1 + 3 files changed, 17 insertions(+)
--- 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 */ 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; --- 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; --- 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 {