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Subject[PATCH v2 3/5] char: tpm: rewrite "tpm_tis_req_canceled()"
Date
From: Amir Mizinski <amirmizi6@gmail.com>

Using this function while read/write data resulted in aborted operation.
After investigating according to TCG TPM Profile (PTP) Specifications,
i found cancel should happen only if TPM_STS.commandReady bit is lit
and couldn't find a case when the current condition is valid.
Also only cmdReady bit need to be compared instead of the full lower status register byte.

Signed-off-by: Amir Mizinski <amirmizi6@gmail.com>
---
drivers/char/tpm/tpm_tis_core.c | 12 +-----------
1 file changed, 1 insertion(+), 11 deletions(-)

diff --git a/drivers/char/tpm/tpm_tis_core.c b/drivers/char/tpm/tpm_tis_core.c
index 43784fd..924489c 100644
--- a/drivers/char/tpm/tpm_tis_core.c
+++ b/drivers/char/tpm/tpm_tis_core.c
@@ -631,17 +631,7 @@ static int probe_itpm(struct tpm_chip *chip)

static bool tpm_tis_req_canceled(struct tpm_chip *chip, u8 status)
{
- struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
-
- switch (priv->manufacturer_id) {
- case TPM_VID_WINBOND:
- return ((status == TPM_STS_VALID) ||
- (status == (TPM_STS_VALID | TPM_STS_COMMAND_READY)));
- case TPM_VID_STM:
- return (status == (TPM_STS_VALID | TPM_STS_COMMAND_READY));
- default:
- return (status == TPM_STS_COMMAND_READY);
- }
+ return ((status & TPM_STS_COMMAND_READY) == TPM_STS_COMMAND_READY);
}

static irqreturn_t tis_int_handler(int dummy, void *dev_id)
--
2.7.4
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