Currently, there is an unnecessary 1 msec delay added in
i2c_nuvoton_write_status() for the successful case. This 
function is called multiple times during send() and recv(),
which implies adding multiple extra delays for every TPM
operation.

This patch calls usleep_range() only if retry is to be done.

Signed-off-by: Nayna Jain <na...@linux.vnet.ibm.com>
Cc: sta...@vger.kernel.org (linux-4.8)
Reviewed-by: Mimi Zohar <zo...@linux.vnet.ibm.com>
---
 drivers/char/tpm/tpm_i2c_nuvoton.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/char/tpm/tpm_i2c_nuvoton.c 
b/drivers/char/tpm/tpm_i2c_nuvoton.c
index 0c98c42..c642877 100644
--- a/drivers/char/tpm/tpm_i2c_nuvoton.c
+++ b/drivers/char/tpm/tpm_i2c_nuvoton.c
@@ -124,8 +124,9 @@ static s32 i2c_nuvoton_write_status(struct i2c_client 
*client, u8 data)
        /* this causes the current command to be aborted */
        for (i = 0, status = -1; i < TPM_I2C_RETRY_COUNT && status < 0; i++) {
                status = i2c_nuvoton_write_buf(client, TPM_STS, 1, &data);
-               usleep_range(TPM_I2C_BUS_DELAY, TPM_I2C_BUS_DELAY
-                            + TPM_I2C_DELAY_RANGE);
+               if (status < 0)
+                       usleep_range(TPM_I2C_BUS_DELAY, TPM_I2C_BUS_DELAY
+                                    + TPM_I2C_DELAY_RANGE);
        }
        return status;
 }
-- 
2.9.3


------------------------------------------------------------------------------
Announcing the Oxford Dictionaries API! The API offers world-renowned
dictionary content that is easy and intuitive to access. Sign up for an
account today to start using our lexical data to power your apps and
projects. Get started today and enter our developer competition.
http://sdm.link/oxford
_______________________________________________
tpmdd-devel mailing list
tpmdd-devel@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/tpmdd-devel

Reply via email to