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authorStefan Berger <stefanb@linux.vnet.ibm.com>2013-01-22 13:52:35 -0600
committerKent Yoder <key@linux.vnet.ibm.com>2013-02-05 09:38:24 -0600
commit1f866057291fc00f14e4962473bd7724ffa8f578 (patch)
treeea780b029f24530a32913fa983a60f1a01a4d0d4 /drivers/char/tpm/tpm_nsc.c
parent3e3a5e906998b090ad929010a5f5082ac0dbbdfb (diff)
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tpm: Fix cancellation of TPM commands (polling mode)
On one of my machines the cancellation of TPM commands does not work. The reason is that by writing into sysfs 'cancel' the tpm_tis_ready call causes the status flag TPM_STS_VALID to be set in the statusregister. However, the TIS driver seems to wait for TPM_STS_COMMAND_READY. Once a 2nd time sysfs 'cancel' is written to, the TPM_STS_COMMAND_READY flag also gets set, resulting in TPM_STS_VALID|TPM_STS_COMMAND_READY to be read from the status register. This patch now converts req_canceled into a function to enable more complex comparisons against possible cancellation status codes. Signed-off-by: Stefan Berger <stefanb@linux.vnet.ibm.com> Signed-off-by: Kent Yoder <key@linux.vnet.ibm.com>
Diffstat (limited to 'drivers/char/tpm/tpm_nsc.c')
-rw-r--r--drivers/char/tpm/tpm_nsc.c7
1 files changed, 6 insertions, 1 deletions
diff --git a/drivers/char/tpm/tpm_nsc.c b/drivers/char/tpm/tpm_nsc.c
index 640c9a427b59..770c46f8eb30 100644
--- a/drivers/char/tpm/tpm_nsc.c
+++ b/drivers/char/tpm/tpm_nsc.c
@@ -227,6 +227,11 @@ static u8 tpm_nsc_status(struct tpm_chip *chip)
return inb(chip->vendor.base + NSC_STATUS);
}
+static bool tpm_nsc_req_canceled(struct tpm_chip *chip, u8 status)
+{
+ return (status == NSC_STATUS_RDY);
+}
+
static const struct file_operations nsc_ops = {
.owner = THIS_MODULE,
.llseek = no_llseek,
@@ -258,7 +263,7 @@ static const struct tpm_vendor_specific tpm_nsc = {
.status = tpm_nsc_status,
.req_complete_mask = NSC_STATUS_OBF,
.req_complete_val = NSC_STATUS_OBF,
- .req_canceled = NSC_STATUS_RDY,
+ .req_canceled = tpm_nsc_req_canceled,
.attr_group = &nsc_attr_grp,
.miscdev = { .fops = &nsc_ops, },
};