Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965528AbbGVQZ3 (ORCPT ); Wed, 22 Jul 2015 12:25:29 -0400 Received: from eusmtp01.atmel.com ([212.144.249.243]:35858 "EHLO eusmtp01.atmel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934661AbbGVQZ1 (ORCPT ); Wed, 22 Jul 2015 12:25:27 -0400 Message-ID: <55AFC3F0.5050002@atmel.com> Date: Wed, 22 Jul 2015 18:25:20 +0200 From: Cyrille Pitchen User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.7.0 MIME-Version: 1.0 To: Marek Vasut CC: , , , , , , , , , , , , , , , , , , Subject: Re: [PATCH v2 1/5] mtd: spi-nor: notify (Q)SPI controller about protocol change References: <036f143509fed3f303508d1688d68012790f835a.1437569902.git.cyrille.pitchen@atmel.com> <201507221541.46135.marex@denx.de> In-Reply-To: <201507221541.46135.marex@denx.de> Content-Type: text/plain; charset="windows-1252" Content-Transfer-Encoding: 8bit X-Originating-IP: [10.161.30.18] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2368 Lines: 69 Hi Marek, Le 22/07/2015 15:41, Marek Vasut a ?crit : > On Wednesday, July 22, 2015 at 03:17:06 PM, Cyrille Pitchen wrote: >> Once the Quad SPI mode has been enabled on a Micron flash memory, this >> device expects ALL the following commands to use the SPI 4-4-4 protocol. >> The (Q)SPI controller needs to be notified about the protocol change so it >> can adapt and keep on dialoging with the Micron memory. >> >> Signed-off-by: Cyrille Pitchen >> --- >> drivers/mtd/spi-nor/spi-nor.c | 17 +++++++++++++++++ >> include/linux/mtd/spi-nor.h | 13 +++++++++++++ >> 2 files changed, 30 insertions(+) >> >> diff --git a/drivers/mtd/spi-nor/spi-nor.c b/drivers/mtd/spi-nor/spi-nor.c >> index d78831b4422b..93627d4e6be8 100644 >> --- a/drivers/mtd/spi-nor/spi-nor.c >> +++ b/drivers/mtd/spi-nor/spi-nor.c >> @@ -163,6 +163,18 @@ static inline int write_disable(struct spi_nor *nor) >> return nor->write_reg(nor, SPINOR_OP_WRDI, NULL, 0, 0); >> } >> >> +/* >> + * Notify the (Q)SPI controller about the new protocol to be used. > > Hi! > > Can you please just reword this a little, so that it is absolutelly clear > even to the less bright of us (like me) that this is a notification coming > from the upper layers (ie. the spi-nor framework) toward the hardware ? > Sure, no problem! what about the following? /* * Let the spi-nor framework notify lower layers, especially the driver of the * (Q)SPI controller, about the new protocol to be used. Indeed, once the * spi-nor framework has sent manufacturer specific commands to a memory to * enable its Quad SPI mode, it should immediately after tell the QSPI * controller to use the very same Quad SPI protocol as expected by the memory. */ >> + */ >> +static inline int spi_nor_set_protocol(struct spi_nor *nor, >> + enum spi_protocol proto) >> +{ >> + if (nor->set_protocol) >> + return nor->set_protocol(nor, proto); >> + >> + return 0; >> +} >> + >> static inline struct spi_nor *mtd_to_spi_nor(struct mtd_info *mtd) >> { >> return mtd->priv; > > [...] > > Best regards, > Marek Vasut > Best regards, Cyrille -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/