Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752582AbdCMS0Q (ORCPT ); Mon, 13 Mar 2017 14:26:16 -0400 Received: from mga05.intel.com ([192.55.52.43]:31723 "EHLO mga05.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750808AbdCMS0J (ORCPT ); Mon, 13 Mar 2017 14:26:09 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.36,160,1486454400"; d="scan'208";a="74913549" Date: Mon, 13 Mar 2017 20:26:04 +0200 From: Jarkko Sakkinen To: Mimi Zohar Cc: tpmdd-devel@lists.sourceforge.net, linux-kernel@vger.kernel.org, linux-security-module@vger.kernel.org, "linux-4.8" , Nayna Jain Subject: Re: [tpmdd-devel] [PATCH 2/2] tpm: add sleep only for retry in i2c_nuvoton_write_status() Message-ID: <20170313182604.yhfhbqve2wufa2f4@intel.com> References: <1489171554-6844-1-git-send-email-nayna@linux.vnet.ibm.com> <1489171554-6844-2-git-send-email-nayna@linux.vnet.ibm.com> <1489416862.28954.156.camel@linux.vnet.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1489416862.28954.156.camel@linux.vnet.ibm.com> Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo User-Agent: Mutt/1.6.2-neo (2016-08-21) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1796 Lines: 53 On Mon, Mar 13, 2017 at 10:54:22AM -0400, Mimi Zohar wrote: > 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 Yes, sure. I'll try to get that done as soon as possible.. /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; > > } > >