[PATCH v4 3/7] tpm: tpm_tis: rewrite "tpm_tis_req_canceled()"

From: <amirmizi6@gmail.com>
To: <Eyal.Cohen@nuvoton.com>, <jarkko.sakkinen@linux.intel.com>,
	<oshrialkoby85@gmail.com>, <alexander.steffen@infineon.com>,
	<robh+dt@kernel.org>, <mark.rutland@arm.com>, <peterhuewe@gmx.de>,
	<jgg@ziepe.ca>, <arnd@arndb.de>, <gregkh@linuxfoundation.org>
Cc: <devicetree@vger.kernel.org>, <linux-kernel@vger.kernel.org>,
	<linux-integrity@vger.kernel.org>, <oshri.alkoby@nuvoton.com>,
	<tmaimon77@gmail.com>, <gcwilson@us.ibm.com>,
	<kgoldman@us.ibm.com>, <Dan.Morav@nuvoton.com>,
	<oren.tanami@nuvoton.com>, <shmulik.hager@nuvoton.com>,
	<amir.mizinski@nuvoton.com>, Amir Mizinski <amirmizi6@gmail.com>
Subject: [PATCH v4 3/7] tpm: tpm_tis: rewrite "tpm_tis_req_canceled()"
Date: Tue, 31 Mar 2020 14:32:03 +0300	[thread overview]
Message-ID: <20200331113207.107080-4-amirmizi6@gmail.com> (raw)
In-Reply-To: <20200331113207.107080-1-amirmizi6@gmail.com>

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 6c4f232..18b9dc4 100644
--- a/drivers/char/tpm/tpm_tis_core.c
+++ b/drivers/char/tpm/tpm_tis_core.c
@@ -710,17 +710,7 @@ 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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