diff mbox

[v9,3/5] tpm: Clean up reading of timeout and duration capabilities

Message ID 1468426776-42762-4-git-send-email-eswierk@skyportsystems.com (mailing list archive)
State New, archived
Headers show

Commit Message

Ed Swierk July 13, 2016, 4:19 p.m. UTC
Call tpm_getcap() from tpm_get_timeouts() to eliminate redundant
code. Return all errors to the caller rather than swallowing them
(e.g. when tpm_transmit_cmd() returns nonzero).

Signed-off-by: Ed Swierk <eswierk@skyportsystems.com>
---
 drivers/char/tpm/tpm-interface.c | 74 +++++++++++++++-------------------------
 1 file changed, 27 insertions(+), 47 deletions(-)

Comments

Jarkko Sakkinen July 18, 2016, 6:15 p.m. UTC | #1
On Wed, Jul 13, 2016 at 09:19:34AM -0700, Ed Swierk wrote:
> Call tpm_getcap() from tpm_get_timeouts() to eliminate redundant
> code. Return all errors to the caller rather than swallowing them
> (e.g. when tpm_transmit_cmd() returns nonzero).
> 
> Signed-off-by: Ed Swierk <eswierk@skyportsystems.com>

Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>

/Jarkko

> ---
>  drivers/char/tpm/tpm-interface.c | 74 +++++++++++++++-------------------------
>  1 file changed, 27 insertions(+), 47 deletions(-)
> 
> diff --git a/drivers/char/tpm/tpm-interface.c b/drivers/char/tpm/tpm-interface.c
> index a4beb53..dc492ee 100644
> --- a/drivers/char/tpm/tpm-interface.c
> +++ b/drivers/char/tpm/tpm-interface.c
> @@ -460,9 +460,19 @@ ssize_t tpm_getcap(struct tpm_chip *chip, __be32 subcap_id, cap_t *cap,
>  		tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
>  		tpm_cmd.params.getcap_in.subcap = subcap_id;
>  	}
> +
>  	rc = tpm_transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE, desc);
> +
> +	if (!rc &&
> +	    ((subcap_id == TPM_CAP_PROP_TIS_TIMEOUT &&
> +	      be32_to_cpu(tpm_cmd.header.out.length) != TPM_HEADER_SIZE + 20) ||
> +	     (subcap_id == TPM_CAP_PROP_TIS_DURATION &&
> +	      be32_to_cpu(tpm_cmd.header.out.length) != TPM_HEADER_SIZE + 16)))
> +		rc = -EINVAL;
> +
>  	if (!rc)
>  		*cap = tpm_cmd.params.getcap_out.cap;
> +
>  	return rc;
>  }
>  
> @@ -503,10 +513,9 @@ static int tpm_startup(struct tpm_chip *chip, __be16 startup_type)
>  
>  int tpm_get_timeouts(struct tpm_chip *chip)
>  {
> -	struct tpm_cmd_t tpm_cmd;
> +	cap_t cap;
>  	unsigned long new_timeout[4];
>  	unsigned long old_timeout[4];
> -	struct duration_t *duration_cap;
>  	ssize_t rc;
>  
>  	if (chip->flags & TPM_CHIP_FLAG_TPM2) {
> @@ -524,42 +533,25 @@ int tpm_get_timeouts(struct tpm_chip *chip)
>  		return 0;
>  	}
>  
> -	tpm_cmd.header.in = tpm_getcap_header;
> -	tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
> -	tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
> -	tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_TIMEOUT;
> -	rc = tpm_transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE, NULL);
> -
> +	rc = tpm_getcap(chip, TPM_CAP_PROP_TIS_TIMEOUT, &cap,
> +			"attempting to determine the timeouts");
>  	if (rc == TPM_ERR_INVALID_POSTINIT) {
>  		/* The TPM is not started, we are the first to talk to it.
>  		   Execute a startup command. */
> -		dev_info(&chip->dev, "Issuing TPM_STARTUP");
> +		dev_info(&chip->dev, "Issuing TPM_STARTUP\n");
>  		if (tpm_startup(chip, TPM_ST_CLEAR))
>  			return rc;
>  
> -		tpm_cmd.header.in = tpm_getcap_header;
> -		tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
> -		tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
> -		tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_TIMEOUT;
> -		rc = tpm_transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE,
> -				  NULL);
> -	}
> -	if (rc) {
> -		dev_err(&chip->dev,
> -			"A TPM error (%zd) occurred attempting to determine the timeouts\n",
> -			rc);
> -		goto duration;
> +		rc = tpm_getcap(chip, TPM_CAP_PROP_TIS_TIMEOUT, &cap,
> +				"attempting to determine the timeouts");
>  	}
> +	if (rc)
> +		return rc;
>  
> -	if (be32_to_cpu(tpm_cmd.header.out.return_code) != 0 ||
> -	    be32_to_cpu(tpm_cmd.header.out.length)
> -	    != sizeof(tpm_cmd.header.out) + sizeof(u32) + 4 * sizeof(u32))
> -		return -EINVAL;
> -
> -	old_timeout[0] = be32_to_cpu(tpm_cmd.params.getcap_out.cap.timeout.a);
> -	old_timeout[1] = be32_to_cpu(tpm_cmd.params.getcap_out.cap.timeout.b);
> -	old_timeout[2] = be32_to_cpu(tpm_cmd.params.getcap_out.cap.timeout.c);
> -	old_timeout[3] = be32_to_cpu(tpm_cmd.params.getcap_out.cap.timeout.d);
> +	old_timeout[0] = be32_to_cpu(cap.timeout.a);
> +	old_timeout[1] = be32_to_cpu(cap.timeout.b);
> +	old_timeout[2] = be32_to_cpu(cap.timeout.c);
> +	old_timeout[3] = be32_to_cpu(cap.timeout.d);
>  	memcpy(new_timeout, old_timeout, sizeof(new_timeout));
>  
>  	/*
> @@ -597,29 +589,17 @@ int tpm_get_timeouts(struct tpm_chip *chip)
>  	chip->timeout_c = usecs_to_jiffies(new_timeout[2]);
>  	chip->timeout_d = usecs_to_jiffies(new_timeout[3]);
>  
> -duration:
> -	tpm_cmd.header.in = tpm_getcap_header;
> -	tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
> -	tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
> -	tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_DURATION;
> -
> -	rc = tpm_transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE,
> -			      "attempting to determine the durations");
> +	rc = tpm_getcap(chip, TPM_CAP_PROP_TIS_DURATION, &cap,
> +			"attempting to determine the durations");
>  	if (rc)
>  		return rc;
>  
> -	if (be32_to_cpu(tpm_cmd.header.out.return_code) != 0 ||
> -	    be32_to_cpu(tpm_cmd.header.out.length)
> -	    != sizeof(tpm_cmd.header.out) + sizeof(u32) + 3 * sizeof(u32))
> -		return -EINVAL;
> -
> -	duration_cap = &tpm_cmd.params.getcap_out.cap.duration;
>  	chip->duration[TPM_SHORT] =
> -	    usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_short));
> +		usecs_to_jiffies(be32_to_cpu(cap.duration.tpm_short));
>  	chip->duration[TPM_MEDIUM] =
> -	    usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_medium));
> +		usecs_to_jiffies(be32_to_cpu(cap.duration.tpm_medium));
>  	chip->duration[TPM_LONG] =
> -	    usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_long));
> +		usecs_to_jiffies(be32_to_cpu(cap.duration.tpm_long));
>  
>  	/* The Broadcom BCM0102 chipset in a Dell Latitude D820 gets the above
>  	 * value wrong and apparently reports msecs rather than usecs. So we
> -- 
> 1.9.1
> 

------------------------------------------------------------------------------
What NetFlow Analyzer can do for you? Monitors network bandwidth and traffic
patterns at an interface-level. Reveals which users, apps, and protocols are 
consuming the most bandwidth. Provides multi-vendor support for NetFlow, 
J-Flow, sFlow and other flows. Make informed decisions using capacity planning
reports.http://sdm.link/zohodev2dev
Jarkko Sakkinen July 18, 2016, 6:19 p.m. UTC | #2
On Wed, Jul 13, 2016 at 09:19:34AM -0700, Ed Swierk wrote:
> Call tpm_getcap() from tpm_get_timeouts() to eliminate redundant
> code. Return all errors to the caller rather than swallowing them
> (e.g. when tpm_transmit_cmd() returns nonzero).
> 
> Signed-off-by: Ed Swierk <eswierk@skyportsystems.com>

You have to fix the reported kbuild errors.

/Jarkko

> ---
>  drivers/char/tpm/tpm-interface.c | 74 +++++++++++++++-------------------------
>  1 file changed, 27 insertions(+), 47 deletions(-)
> 
> diff --git a/drivers/char/tpm/tpm-interface.c b/drivers/char/tpm/tpm-interface.c
> index a4beb53..dc492ee 100644
> --- a/drivers/char/tpm/tpm-interface.c
> +++ b/drivers/char/tpm/tpm-interface.c
> @@ -460,9 +460,19 @@ ssize_t tpm_getcap(struct tpm_chip *chip, __be32 subcap_id, cap_t *cap,
>  		tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
>  		tpm_cmd.params.getcap_in.subcap = subcap_id;
>  	}
> +
>  	rc = tpm_transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE, desc);
> +
> +	if (!rc &&
> +	    ((subcap_id == TPM_CAP_PROP_TIS_TIMEOUT &&
> +	      be32_to_cpu(tpm_cmd.header.out.length) != TPM_HEADER_SIZE + 20) ||
> +	     (subcap_id == TPM_CAP_PROP_TIS_DURATION &&
> +	      be32_to_cpu(tpm_cmd.header.out.length) != TPM_HEADER_SIZE + 16)))
> +		rc = -EINVAL;
> +
>  	if (!rc)
>  		*cap = tpm_cmd.params.getcap_out.cap;
> +
>  	return rc;
>  }
>  
> @@ -503,10 +513,9 @@ static int tpm_startup(struct tpm_chip *chip, __be16 startup_type)
>  
>  int tpm_get_timeouts(struct tpm_chip *chip)
>  {
> -	struct tpm_cmd_t tpm_cmd;
> +	cap_t cap;
>  	unsigned long new_timeout[4];
>  	unsigned long old_timeout[4];
> -	struct duration_t *duration_cap;
>  	ssize_t rc;
>  
>  	if (chip->flags & TPM_CHIP_FLAG_TPM2) {
> @@ -524,42 +533,25 @@ int tpm_get_timeouts(struct tpm_chip *chip)
>  		return 0;
>  	}
>  
> -	tpm_cmd.header.in = tpm_getcap_header;
> -	tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
> -	tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
> -	tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_TIMEOUT;
> -	rc = tpm_transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE, NULL);
> -
> +	rc = tpm_getcap(chip, TPM_CAP_PROP_TIS_TIMEOUT, &cap,
> +			"attempting to determine the timeouts");
>  	if (rc == TPM_ERR_INVALID_POSTINIT) {
>  		/* The TPM is not started, we are the first to talk to it.
>  		   Execute a startup command. */
> -		dev_info(&chip->dev, "Issuing TPM_STARTUP");
> +		dev_info(&chip->dev, "Issuing TPM_STARTUP\n");
>  		if (tpm_startup(chip, TPM_ST_CLEAR))
>  			return rc;
>  
> -		tpm_cmd.header.in = tpm_getcap_header;
> -		tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
> -		tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
> -		tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_TIMEOUT;
> -		rc = tpm_transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE,
> -				  NULL);
> -	}
> -	if (rc) {
> -		dev_err(&chip->dev,
> -			"A TPM error (%zd) occurred attempting to determine the timeouts\n",
> -			rc);
> -		goto duration;
> +		rc = tpm_getcap(chip, TPM_CAP_PROP_TIS_TIMEOUT, &cap,
> +				"attempting to determine the timeouts");
>  	}
> +	if (rc)
> +		return rc;
>  
> -	if (be32_to_cpu(tpm_cmd.header.out.return_code) != 0 ||
> -	    be32_to_cpu(tpm_cmd.header.out.length)
> -	    != sizeof(tpm_cmd.header.out) + sizeof(u32) + 4 * sizeof(u32))
> -		return -EINVAL;
> -
> -	old_timeout[0] = be32_to_cpu(tpm_cmd.params.getcap_out.cap.timeout.a);
> -	old_timeout[1] = be32_to_cpu(tpm_cmd.params.getcap_out.cap.timeout.b);
> -	old_timeout[2] = be32_to_cpu(tpm_cmd.params.getcap_out.cap.timeout.c);
> -	old_timeout[3] = be32_to_cpu(tpm_cmd.params.getcap_out.cap.timeout.d);
> +	old_timeout[0] = be32_to_cpu(cap.timeout.a);
> +	old_timeout[1] = be32_to_cpu(cap.timeout.b);
> +	old_timeout[2] = be32_to_cpu(cap.timeout.c);
> +	old_timeout[3] = be32_to_cpu(cap.timeout.d);
>  	memcpy(new_timeout, old_timeout, sizeof(new_timeout));
>  
>  	/*
> @@ -597,29 +589,17 @@ int tpm_get_timeouts(struct tpm_chip *chip)
>  	chip->timeout_c = usecs_to_jiffies(new_timeout[2]);
>  	chip->timeout_d = usecs_to_jiffies(new_timeout[3]);
>  
> -duration:
> -	tpm_cmd.header.in = tpm_getcap_header;
> -	tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
> -	tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
> -	tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_DURATION;
> -
> -	rc = tpm_transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE,
> -			      "attempting to determine the durations");
> +	rc = tpm_getcap(chip, TPM_CAP_PROP_TIS_DURATION, &cap,
> +			"attempting to determine the durations");
>  	if (rc)
>  		return rc;
>  
> -	if (be32_to_cpu(tpm_cmd.header.out.return_code) != 0 ||
> -	    be32_to_cpu(tpm_cmd.header.out.length)
> -	    != sizeof(tpm_cmd.header.out) + sizeof(u32) + 3 * sizeof(u32))
> -		return -EINVAL;
> -
> -	duration_cap = &tpm_cmd.params.getcap_out.cap.duration;
>  	chip->duration[TPM_SHORT] =
> -	    usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_short));
> +		usecs_to_jiffies(be32_to_cpu(cap.duration.tpm_short));
>  	chip->duration[TPM_MEDIUM] =
> -	    usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_medium));
> +		usecs_to_jiffies(be32_to_cpu(cap.duration.tpm_medium));
>  	chip->duration[TPM_LONG] =
> -	    usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_long));
> +		usecs_to_jiffies(be32_to_cpu(cap.duration.tpm_long));
>  
>  	/* The Broadcom BCM0102 chipset in a Dell Latitude D820 gets the above
>  	 * value wrong and apparently reports msecs rather than usecs. So we
> -- 
> 1.9.1
> 

------------------------------------------------------------------------------
What NetFlow Analyzer can do for you? Monitors network bandwidth and traffic
patterns at an interface-level. Reveals which users, apps, and protocols are 
consuming the most bandwidth. Provides multi-vendor support for NetFlow, 
J-Flow, sFlow and other flows. Make informed decisions using capacity planning
reports.http://sdm.link/zohodev2dev
Jarkko Sakkinen July 18, 2016, 6:20 p.m. UTC | #3
On Mon, Jul 18, 2016 at 09:19:53PM +0300, Jarkko Sakkinen wrote:
> On Wed, Jul 13, 2016 at 09:19:34AM -0700, Ed Swierk wrote:
> > Call tpm_getcap() from tpm_get_timeouts() to eliminate redundant
> > code. Return all errors to the caller rather than swallowing them
> > (e.g. when tpm_transmit_cmd() returns nonzero).
> > 
> > Signed-off-by: Ed Swierk <eswierk@skyportsystems.com>
> 
> You have to fix the reported kbuild errors.

Please ignore this :) Pressed send button by mistake in mutt.

/Jarkko

------------------------------------------------------------------------------
What NetFlow Analyzer can do for you? Monitors network bandwidth and traffic
patterns at an interface-level. Reveals which users, apps, and protocols are 
consuming the most bandwidth. Provides multi-vendor support for NetFlow, 
J-Flow, sFlow and other flows. Make informed decisions using capacity planning
reports.http://sdm.link/zohodev2dev
diff mbox

Patch

diff --git a/drivers/char/tpm/tpm-interface.c b/drivers/char/tpm/tpm-interface.c
index a4beb53..dc492ee 100644
--- a/drivers/char/tpm/tpm-interface.c
+++ b/drivers/char/tpm/tpm-interface.c
@@ -460,9 +460,19 @@  ssize_t tpm_getcap(struct tpm_chip *chip, __be32 subcap_id, cap_t *cap,
 		tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
 		tpm_cmd.params.getcap_in.subcap = subcap_id;
 	}
+
 	rc = tpm_transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE, desc);
+
+	if (!rc &&
+	    ((subcap_id == TPM_CAP_PROP_TIS_TIMEOUT &&
+	      be32_to_cpu(tpm_cmd.header.out.length) != TPM_HEADER_SIZE + 20) ||
+	     (subcap_id == TPM_CAP_PROP_TIS_DURATION &&
+	      be32_to_cpu(tpm_cmd.header.out.length) != TPM_HEADER_SIZE + 16)))
+		rc = -EINVAL;
+
 	if (!rc)
 		*cap = tpm_cmd.params.getcap_out.cap;
+
 	return rc;
 }
 
@@ -503,10 +513,9 @@  static int tpm_startup(struct tpm_chip *chip, __be16 startup_type)
 
 int tpm_get_timeouts(struct tpm_chip *chip)
 {
-	struct tpm_cmd_t tpm_cmd;
+	cap_t cap;
 	unsigned long new_timeout[4];
 	unsigned long old_timeout[4];
-	struct duration_t *duration_cap;
 	ssize_t rc;
 
 	if (chip->flags & TPM_CHIP_FLAG_TPM2) {
@@ -524,42 +533,25 @@  int tpm_get_timeouts(struct tpm_chip *chip)
 		return 0;
 	}
 
-	tpm_cmd.header.in = tpm_getcap_header;
-	tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
-	tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
-	tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_TIMEOUT;
-	rc = tpm_transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE, NULL);
-
+	rc = tpm_getcap(chip, TPM_CAP_PROP_TIS_TIMEOUT, &cap,
+			"attempting to determine the timeouts");
 	if (rc == TPM_ERR_INVALID_POSTINIT) {
 		/* The TPM is not started, we are the first to talk to it.
 		   Execute a startup command. */
-		dev_info(&chip->dev, "Issuing TPM_STARTUP");
+		dev_info(&chip->dev, "Issuing TPM_STARTUP\n");
 		if (tpm_startup(chip, TPM_ST_CLEAR))
 			return rc;
 
-		tpm_cmd.header.in = tpm_getcap_header;
-		tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
-		tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
-		tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_TIMEOUT;
-		rc = tpm_transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE,
-				  NULL);
-	}
-	if (rc) {
-		dev_err(&chip->dev,
-			"A TPM error (%zd) occurred attempting to determine the timeouts\n",
-			rc);
-		goto duration;
+		rc = tpm_getcap(chip, TPM_CAP_PROP_TIS_TIMEOUT, &cap,
+				"attempting to determine the timeouts");
 	}
+	if (rc)
+		return rc;
 
-	if (be32_to_cpu(tpm_cmd.header.out.return_code) != 0 ||
-	    be32_to_cpu(tpm_cmd.header.out.length)
-	    != sizeof(tpm_cmd.header.out) + sizeof(u32) + 4 * sizeof(u32))
-		return -EINVAL;
-
-	old_timeout[0] = be32_to_cpu(tpm_cmd.params.getcap_out.cap.timeout.a);
-	old_timeout[1] = be32_to_cpu(tpm_cmd.params.getcap_out.cap.timeout.b);
-	old_timeout[2] = be32_to_cpu(tpm_cmd.params.getcap_out.cap.timeout.c);
-	old_timeout[3] = be32_to_cpu(tpm_cmd.params.getcap_out.cap.timeout.d);
+	old_timeout[0] = be32_to_cpu(cap.timeout.a);
+	old_timeout[1] = be32_to_cpu(cap.timeout.b);
+	old_timeout[2] = be32_to_cpu(cap.timeout.c);
+	old_timeout[3] = be32_to_cpu(cap.timeout.d);
 	memcpy(new_timeout, old_timeout, sizeof(new_timeout));
 
 	/*
@@ -597,29 +589,17 @@  int tpm_get_timeouts(struct tpm_chip *chip)
 	chip->timeout_c = usecs_to_jiffies(new_timeout[2]);
 	chip->timeout_d = usecs_to_jiffies(new_timeout[3]);
 
-duration:
-	tpm_cmd.header.in = tpm_getcap_header;
-	tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
-	tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
-	tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_DURATION;
-
-	rc = tpm_transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE,
-			      "attempting to determine the durations");
+	rc = tpm_getcap(chip, TPM_CAP_PROP_TIS_DURATION, &cap,
+			"attempting to determine the durations");
 	if (rc)
 		return rc;
 
-	if (be32_to_cpu(tpm_cmd.header.out.return_code) != 0 ||
-	    be32_to_cpu(tpm_cmd.header.out.length)
-	    != sizeof(tpm_cmd.header.out) + sizeof(u32) + 3 * sizeof(u32))
-		return -EINVAL;
-
-	duration_cap = &tpm_cmd.params.getcap_out.cap.duration;
 	chip->duration[TPM_SHORT] =
-	    usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_short));
+		usecs_to_jiffies(be32_to_cpu(cap.duration.tpm_short));
 	chip->duration[TPM_MEDIUM] =
-	    usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_medium));
+		usecs_to_jiffies(be32_to_cpu(cap.duration.tpm_medium));
 	chip->duration[TPM_LONG] =
-	    usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_long));
+		usecs_to_jiffies(be32_to_cpu(cap.duration.tpm_long));
 
 	/* The Broadcom BCM0102 chipset in a Dell Latitude D820 gets the above
 	 * value wrong and apparently reports msecs rather than usecs. So we