summaryrefslogtreecommitdiffstats
path: root/drivers/char/tpm/tpm.c
diff options
context:
space:
mode:
authorNeilBrown <neilb@suse.de>2010-05-22 08:31:36 +1000
committerNeilBrown <neilb@suse.de>2010-05-22 08:31:36 +1000
commit19fdb9eefb21b72edbc365b838502780c392bad6 (patch)
treedeae04c48532d6eab64ed4b0396737bb854b5506 /drivers/char/tpm/tpm.c
parentbe6800a73aa2f3dc14744c3b80e676d189789f04 (diff)
parent3ff195b011d7decf501a4d55aeed312731094796 (diff)
Merge commit '3ff195b011d7decf501a4d55aeed312731094796' into for-linus
Conflicts: drivers/md/md.c - Resolved conflict in md_update_sb - Added extra 'NULL' arg to new instance of sysfs_get_dirent. Signed-off-by: NeilBrown <neilb@suse.de>
Diffstat (limited to 'drivers/char/tpm/tpm.c')
-rw-r--r--drivers/char/tpm/tpm.c48
1 files changed, 41 insertions, 7 deletions
diff --git a/drivers/char/tpm/tpm.c b/drivers/char/tpm/tpm.c
index f06bb37defb..05ad4a17a28 100644
--- a/drivers/char/tpm/tpm.c
+++ b/drivers/char/tpm/tpm.c
@@ -24,6 +24,7 @@
*/
#include <linux/poll.h>
+#include <linux/slab.h>
#include <linux/mutex.h>
#include <linux/spinlock.h>
@@ -1067,6 +1068,27 @@ void tpm_remove_hardware(struct device *dev)
}
EXPORT_SYMBOL_GPL(tpm_remove_hardware);
+#define TPM_ORD_SAVESTATE cpu_to_be32(152)
+#define SAVESTATE_RESULT_SIZE 10
+
+static struct tpm_input_header savestate_header = {
+ .tag = TPM_TAG_RQU_COMMAND,
+ .length = cpu_to_be32(10),
+ .ordinal = TPM_ORD_SAVESTATE
+};
+
+/* Bug workaround - some TPM's don't flush the most
+ * recently changed pcr on suspend, so force the flush
+ * with an extend to the selected _unused_ non-volatile pcr.
+ */
+static int tpm_suspend_pcr;
+static int __init tpm_suspend_setup(char *str)
+{
+ get_option(&str, &tpm_suspend_pcr);
+ return 1;
+}
+__setup("tpm_suspend_pcr=", tpm_suspend_setup);
+
/*
* We are about to suspend. Save the TPM state
* so that it can be restored.
@@ -1074,17 +1096,29 @@ EXPORT_SYMBOL_GPL(tpm_remove_hardware);
int tpm_pm_suspend(struct device *dev, pm_message_t pm_state)
{
struct tpm_chip *chip = dev_get_drvdata(dev);
- u8 savestate[] = {
- 0, 193, /* TPM_TAG_RQU_COMMAND */
- 0, 0, 0, 10, /* blob length (in bytes) */
- 0, 0, 0, 152 /* TPM_ORD_SaveState */
- };
+ struct tpm_cmd_t cmd;
+ int rc;
+
+ u8 dummy_hash[TPM_DIGEST_SIZE] = { 0 };
if (chip == NULL)
return -ENODEV;
- tpm_transmit(chip, savestate, sizeof(savestate));
- return 0;
+ /* for buggy tpm, flush pcrs with extend to selected dummy */
+ if (tpm_suspend_pcr) {
+ cmd.header.in = pcrextend_header;
+ cmd.params.pcrextend_in.pcr_idx = cpu_to_be32(tpm_suspend_pcr);
+ memcpy(cmd.params.pcrextend_in.hash, dummy_hash,
+ TPM_DIGEST_SIZE);
+ rc = transmit_cmd(chip, &cmd, EXTEND_PCR_RESULT_SIZE,
+ "extending dummy pcr before suspend");
+ }
+
+ /* now do the actual savestate */
+ cmd.header.in = savestate_header;
+ rc = transmit_cmd(chip, &cmd, SAVESTATE_RESULT_SIZE,
+ "sending savestate before suspend");
+ return rc;
}
EXPORT_SYMBOL_GPL(tpm_pm_suspend);