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    SubjectRe: [PATCH 2/2] tpm: add sleep only for retry in i2c_nuvoton_write_status()
    On Fri, Mar 10, 2017 at 01:45:54PM -0500, Nayna Jain wrote:
    > 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 <nayna@linux.vnet.ibm.com>
    > Cc: stable@vger.kernel.org (linux-4.8)
    > Reviewed-by: Mimi Zohar <zohar@linux.vnet.ibm.com>

    I applied this too.

    /Jarkko

    > ---
    > 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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