From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S935819AbcLMRMP (ORCPT ); Tue, 13 Dec 2016 12:12:15 -0500 Received: from 4.mo4.mail-out.ovh.net ([178.32.98.131]:37794 "EHLO 4.mo4.mail-out.ovh.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934133AbcLMRML (ORCPT ); Tue, 13 Dec 2016 12:12:11 -0500 Subject: Re: [PATCH 1/1] mtd: spi-nor: improve macronix_quad_enable() To: Marek Vasut , Cyrille Pitchen References: <5b7ad2367d9b6a4e3a766ce6cadf16c313a03a26.1481039788.git.cyrille.pitchen@atmel.com> <5962912d-b5de-f0d0-077b-af3b9ff2a77c@gmail.com> Cc: boris.brezillon@free-electrons.com, computersforpeace@gmail.com, linux-mtd@lists.infradead.org, linux-kernel@vger.kernel.org, richard@nod.at From: Cyrille Pitchen Message-ID: <2a16b055-76bb-1e97-f07a-0ae715721743@wedev4u.fr> Date: Tue, 13 Dec 2016 17:35:04 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.5.1 MIME-Version: 1.0 In-Reply-To: <5962912d-b5de-f0d0-077b-af3b9ff2a77c@gmail.com> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 8bit X-Ovh-Tracer-Id: 2540030192426833729 X-VR-SPAMSTATE: OK X-VR-SPAMSCORE: -100 X-VR-SPAMCAUSE: gggruggvucftvghtrhhoucdtuddrfeelfedrieeggdefjecutefuodetggdotefrodftvfcurfhrohhfihhlvgemucfqggfjpdevjffgvefmvefgnecuuegrihhlohhuthemuceftddtnecusecvtfgvtghiphhivghnthhsucdlqddutddtmd Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Le 06/12/2016 à 20:01, Marek Vasut a écrit : > On 12/06/2016 05:01 PM, Cyrille Pitchen wrote: >> The patch checks whether the Quad Enable bit is already set in the Status >> Register. If so, the function exits immediately with a successful return >> code. > > Performance optimization I presume ? > > Acked-by: Marek Vasut > >> Signed-off-by: Cyrille Pitchen >> Reviewed-by: Jagan Teki Applied to git://github.com/spi-nor/linux.git >> --- >> drivers/mtd/spi-nor/spi-nor.c | 3 +++ >> 1 file changed, 3 insertions(+) >> >> diff --git a/drivers/mtd/spi-nor/spi-nor.c b/drivers/mtd/spi-nor/spi-nor.c >> index da7cd69d4857..1fd32b991eb7 100644 >> --- a/drivers/mtd/spi-nor/spi-nor.c >> +++ b/drivers/mtd/spi-nor/spi-nor.c >> @@ -1216,6 +1216,9 @@ static int macronix_quad_enable(struct spi_nor *nor) >> val = read_sr(nor); >> if (val < 0) >> return val; >> + if (val & SR_QUAD_EN_MX) >> + return 0; >> + >> write_enable(nor); >> >> write_sr(nor, val | SR_QUAD_EN_MX); >> > >