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 <[email protected]>
Cc: [email protected] (linux-4.8)
Reviewed-by: Mimi Zohar <[email protected]>
---
 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

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