From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mimi Zohar Subject: Re: [PATCH 2/2] tpm: add sleep only for retry in i2c_nuvoton_write_status() Date: Mon, 13 Mar 2017 10:54:22 -0400 Message-ID: <1489416862.28954.156.camel@linux.vnet.ibm.com> References: <1489171554-6844-1-git-send-email-nayna@linux.vnet.ibm.com> <1489171554-6844-2-git-send-email-nayna@linux.vnet.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1489171554-6844-2-git-send-email-nayna-23VcF4HTsmIX0ybBhKVfKdBPR1lH4CV8@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: tpmdd-devel-bounces-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org To: Jarkko Sakkinen Cc: linux-security-module-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, tpmdd-devel-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, "linux-4.8" List-Id: tpmdd-devel@lists.sourceforge.net Hi Jarkko, On Fri, 2017-03-10 at 13:45 -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 > Cc: stable-u79uwXL29TY76Z2rM5mHXA@public.gmane.org (linux-4.8) > Reviewed-by: Mimi Zohar Either Reviewed-by/Acked-by is fine. Can you pick up this patch and replace the original version of "tpm: msleep() delays - replace with usleep_range()" with the one Nayna posted? Thanks! Mimi > --- > 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; > } ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, Slashdot.org! http://sdm.link/slashdot