From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:50534 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1753230AbdCMOzU (ORCPT ); Mon, 13 Mar 2017 10:55:20 -0400 Received: from pps.filterd (m0098420.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.0.20/8.16.0.20) with SMTP id v2DEricm120248 for ; Mon, 13 Mar 2017 10:55:19 -0400 Received: from e23smtp01.au.ibm.com (e23smtp01.au.ibm.com [202.81.31.143]) by mx0b-001b2d01.pphosted.com with ESMTP id 295vx5t6du-1 (version=TLSv1.2 cipher=AES256-SHA bits=256 verify=NOT) for ; Mon, 13 Mar 2017 10:55:18 -0400 Received: from localhost by e23smtp01.au.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Tue, 14 Mar 2017 00:55:15 +1000 Subject: Re: [tpmdd-devel] [PATCH 2/2] tpm: add sleep only for retry in i2c_nuvoton_write_status() From: Mimi Zohar To: Jarkko Sakkinen Cc: tpmdd-devel@lists.sourceforge.net, linux-kernel@vger.kernel.org, linux-security-module@vger.kernel.org, "linux-4.8" , Nayna Jain Date: Mon, 13 Mar 2017 10:54:22 -0400 In-Reply-To: <1489171554-6844-2-git-send-email-nayna@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> Content-Type: text/plain; charset="UTF-8" Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Message-Id: <1489416862.28954.156.camel@linux.vnet.ibm.com> Sender: stable-owner@vger.kernel.org List-ID: 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@vger.kernel.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; > }