This is a note to let you know that I've just added the patch titled
tpm: add sleep only for retry in i2c_nuvoton_write_status()
to the 4.9-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
tpm-add-sleep-only-for-retry-in-i2c_nuvoton_write_status.patch
and it can be found in the queue-4.9 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 0afb7118ae021e80ecf70f5a3336e0935505518a Mon Sep 17 00:00:00 2001
From: Nayna Jain <nayna@xxxxxxxxxxxxxxxxxx>
Date: Fri, 10 Mar 2017 13:45:54 -0500
Subject: tpm: add sleep only for retry in i2c_nuvoton_write_status()
From: Nayna Jain <nayna@xxxxxxxxxxxxxxxxxx>
commit 0afb7118ae021e80ecf70f5a3336e0935505518a upstream.
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@xxxxxxxxxxxxxxxxxx>
Reviewed-by: Mimi Zohar <zohar@xxxxxxxxxxxxxxxxxx>
Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@xxxxxxxxxxxxxxx>
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@xxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/char/tpm/tpm_i2c_nuvoton.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
--- 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(stru
/* 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;
}
Patches currently in stable-queue which might be from nayna@xxxxxxxxxxxxxxxxxx are
queue-4.9/tpm-msleep-delays-replace-with-usleep_range-in-i2c-nuvoton-driver.patch
queue-4.9/tpm-add-sleep-only-for-retry-in-i2c_nuvoton_write_status.patch