From: Fabio Estevam <festevam-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
To: Thomas Petazzoni
<thomas.petazzoni-wi1+55ScJUtKEb57/3fJTNBPR1lH4CV8@public.gmane.org>
Cc: Marek Vasut <marex-ynQEQJNshbs@public.gmane.org>,
Fabio Estevam
<fabio.estevam-KZfg59tc24xl57MIdRCFDg@public.gmane.org>,
Shawn Guo <shawn.guo-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org>,
Mark Brown
<broonie-yzvPICuk2AATkU/dhu1WVueM+bqZidxxQQ4Iyu8u01E@public.gmane.org>,
Attila Kinali <attila-HB9FjVmMKa7tRgLqZ5aouw@public.gmane.org>,
spi-devel-general-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org,
Chris Ball <cjb-2X9k7bc8m7Mdnm+yROfE0A@public.gmane.org>,
Dong Aisheng <b29396-KZfg59tc24xl57MIdRCFDg@public.gmane.org>,
Linux ARM kernel
<linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org>
Subject: Re: [PATCH 06/10 V2] spi: Add SPI driver for mx233/mx28
Date: Fri, 3 Aug 2012 10:46:06 -0300 [thread overview]
Message-ID: <CAOMZO5AQs1NzJBogcLPcKtY=QSaxpDmzUTvpfScY7P10FEoMJw@mail.gmail.com> (raw)
In-Reply-To: <20120803153815.758dc064@skate>
On Fri, Aug 3, 2012 at 10:38 AM, Thomas Petazzoni
<thomas.petazzoni-wi1+55ScJUtKEb57/3fJTNBPR1lH4CV8@public.gmane.org> wrote:
>
> It sounds really strange to manipulate WAIT_FOR_CMD and WAIT_FOR_IRQ
> bits to adjust the chip select, and when reading the driver, it seemed
> suspicious to me. After going through the datasheet, indeed those bits
> are the appropriate one to select between the SS0, SS1 and SS2 chip
> selects, but I find the code not really obvious. Would it be possible
> to make it more obvious either by adding or comment or doing something
> like:
>
> /* Should be put in some header file */
> #define BM_SSP_CTRL0_SPI_CS_BITS (20)
>
> +static void mxs_spi_set_cs(struct mxs_spi *spi, unsigned cs)
> +{
> + struct mxs_ssp *ssp = &spi->ssp;
> +
> + writel(0x3 << BM_SSP_CTRL0_SPI_CS_BITS,
> + ssp->base + HW_SSP_CTRL0 + STMP_OFFSET_REG_CLR);
> + writel(cs,
> + ssp->base + HW_SSP_CTRL0 + STMP_OFFSET_REG_SET);
> +}
I agree with Thomas.
In U-boot I did the following in order to be able to select the
different chip selects:
http://git.denx.de/?p=u-boot.git;a=commitdiff;h=148ca64f327a89ef77e84756f5d351af33e59b64
Thanks,
Fabio Estevam
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WARNING: multiple messages have this Message-ID (diff)
From: festevam@gmail.com (Fabio Estevam)
To: linux-arm-kernel@lists.infradead.org
Subject: [PATCH 06/10 V2] spi: Add SPI driver for mx233/mx28
Date: Fri, 3 Aug 2012 10:46:06 -0300 [thread overview]
Message-ID: <CAOMZO5AQs1NzJBogcLPcKtY=QSaxpDmzUTvpfScY7P10FEoMJw@mail.gmail.com> (raw)
In-Reply-To: <20120803153815.758dc064@skate>
On Fri, Aug 3, 2012 at 10:38 AM, Thomas Petazzoni
<thomas.petazzoni@free-electrons.com> wrote:
>
> It sounds really strange to manipulate WAIT_FOR_CMD and WAIT_FOR_IRQ
> bits to adjust the chip select, and when reading the driver, it seemed
> suspicious to me. After going through the datasheet, indeed those bits
> are the appropriate one to select between the SS0, SS1 and SS2 chip
> selects, but I find the code not really obvious. Would it be possible
> to make it more obvious either by adding or comment or doing something
> like:
>
> /* Should be put in some header file */
> #define BM_SSP_CTRL0_SPI_CS_BITS (20)
>
> +static void mxs_spi_set_cs(struct mxs_spi *spi, unsigned cs)
> +{
> + struct mxs_ssp *ssp = &spi->ssp;
> +
> + writel(0x3 << BM_SSP_CTRL0_SPI_CS_BITS,
> + ssp->base + HW_SSP_CTRL0 + STMP_OFFSET_REG_CLR);
> + writel(cs,
> + ssp->base + HW_SSP_CTRL0 + STMP_OFFSET_REG_SET);
> +}
I agree with Thomas.
In U-boot I did the following in order to be able to select the
different chip selects:
http://git.denx.de/?p=u-boot.git;a=commitdiff;h=148ca64f327a89ef77e84756f5d351af33e59b64
Thanks,
Fabio Estevam
next prev parent reply other threads:[~2012-08-03 13:46 UTC|newest]
Thread overview: 62+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-07-23 20:40 [PATCH 00/10 V2] MXS SPI driver Marek Vasut
2012-07-23 20:40 ` Marek Vasut
[not found] ` <1343076052-27312-1-git-send-email-marex-ynQEQJNshbs@public.gmane.org>
2012-07-23 20:40 ` [PATCH 01/10 RESEND] mmc: spi: Move SSP register definitions into separate file Marek Vasut
2012-07-23 20:40 ` Marek Vasut
2012-07-23 20:40 ` [PATCH 02/10 RESEND] mmc: spi: Rename IMX2[38]_MMC to IMX2[38]_SSP Marek Vasut
2012-07-23 20:40 ` Marek Vasut
2012-07-23 20:40 ` [PATCH 03/10 V2] mmc: spi: Add necessary bits into mxs-spi.h Marek Vasut
2012-07-23 20:40 ` Marek Vasut
2012-07-23 20:40 ` [PATCH 04/10 RESEND] mmc: spi: Pull out parts shared between MMC and SPI Marek Vasut
2012-07-23 20:40 ` Marek Vasut
2012-07-23 20:40 ` [PATCH 05/10 V2] mmc: spi: Pull out the SSP clock configuration function Marek Vasut
2012-07-23 20:40 ` Marek Vasut
2012-07-23 20:40 ` [PATCH 06/10 V2] spi: Add SPI driver for mx233/mx28 Marek Vasut
2012-07-23 20:40 ` Marek Vasut
[not found] ` <1343076052-27312-7-git-send-email-marex-ynQEQJNshbs@public.gmane.org>
2012-08-01 20:31 ` Mark Brown
2012-08-01 20:31 ` Mark Brown
[not found] ` <20120801203106.GW4483-yzvPICuk2AATkU/dhu1WVueM+bqZidxxQQ4Iyu8u01E@public.gmane.org>
2012-08-02 14:58 ` Marek Vasut
2012-08-02 14:58 ` Marek Vasut
[not found] ` <201208021658.38237.marex-ynQEQJNshbs@public.gmane.org>
2012-08-02 16:00 ` Mark Brown
2012-08-02 16:00 ` Mark Brown
[not found] ` <20120802160016.GA4537-yzvPICuk2AATkU/dhu1WVueM+bqZidxxQQ4Iyu8u01E@public.gmane.org>
2012-08-02 16:03 ` Marek Vasut
2012-08-02 16:03 ` Marek Vasut
2012-08-03 1:29 ` Shawn Guo
2012-08-03 1:29 ` Shawn Guo
2012-08-03 13:38 ` Thomas Petazzoni
2012-08-03 13:38 ` Thomas Petazzoni
2012-08-03 13:46 ` Fabio Estevam [this message]
2012-08-03 13:46 ` Fabio Estevam
[not found] ` <CAOMZO5AQs1NzJBogcLPcKtY=QSaxpDmzUTvpfScY7P10FEoMJw-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org>
2012-08-03 13:49 ` Marek Vasut
2012-08-03 13:49 ` Marek Vasut
2012-08-03 14:00 ` Marek Vasut
2012-08-03 14:00 ` Marek Vasut
2012-07-23 20:40 ` [PATCH 07/10 RESEND] mmc: spi: Pull out common DMA parts from MXS MMC Marek Vasut
2012-07-23 20:40 ` Marek Vasut
2012-07-23 20:40 ` [PATCH 08/10 RESEND] spi: Add DMA support into SPI driver Marek Vasut
2012-07-23 20:40 ` Marek Vasut
[not found] ` <1343076052-27312-9-git-send-email-marex-ynQEQJNshbs@public.gmane.org>
2012-08-01 20:34 ` Mark Brown
2012-08-01 20:34 ` Mark Brown
[not found] ` <20120801203448.GX4483-yzvPICuk2AATkU/dhu1WVueM+bqZidxxQQ4Iyu8u01E@public.gmane.org>
2012-08-02 15:00 ` Marek Vasut
2012-08-02 15:00 ` Marek Vasut
2012-07-23 20:40 ` [PATCH 09/10 RESEND] spi: Add SSP/SPI device tree documentation Marek Vasut
2012-07-23 20:40 ` Marek Vasut
2012-07-24 18:15 ` Sergei Shtylyov
2012-07-24 18:15 ` Sergei Shtylyov
[not found] ` <500EE64B.8080103-Igf4POYTYCDQT0dZR+AlfA@public.gmane.org>
2012-07-24 19:43 ` Marek Vasut
2012-07-24 19:43 ` Marek Vasut
[not found] ` <201207242143.49038.marex-ynQEQJNshbs@public.gmane.org>
2012-07-28 11:40 ` Shawn Guo
2012-07-28 11:40 ` Shawn Guo
[not found] ` <20120728113957.GE2128-rvtDTF3kK1ictlrPMvKcciBecyulp+rMXqFh9Ls21Oc@public.gmane.org>
2012-07-28 11:42 ` Marek Vasut
2012-07-28 11:42 ` Marek Vasut
2012-07-23 20:40 ` [PATCH 10/10 RESEND] ARM: mx28: Add SPI pinmux into imx28.dtsi Marek Vasut
2012-07-23 20:40 ` Marek Vasut
2012-07-24 9:25 ` [PATCH 00/10 V2] MXS SPI driver Attila Kinali
2012-07-24 9:25 ` Attila Kinali
2012-08-03 14:30 ` [PATCH] SPI: MXS: Allow to pass the SPI master bus number from the device tree Maxime Ripard
2012-08-03 14:30 ` Maxime Ripard
[not found] ` <1344004239-22868-1-git-send-email-maxime.ripard-wi1+55ScJUtKEb57/3fJTNBPR1lH4CV8@public.gmane.org>
2012-08-03 14:43 ` Shawn Guo
2012-08-03 14:43 ` Shawn Guo
[not found] ` <20120803144326.GE23791-rvtDTF3kK1ictlrPMvKcciBecyulp+rMXqFh9Ls21Oc@public.gmane.org>
2012-08-03 16:27 ` Maxime Ripard
2012-08-03 16:27 ` Maxime Ripard
-- strict thread matches above, loose matches on Subject: below --
2012-07-06 6:17 [PATCH 01/10 RESEND] mmc: spi: Move SSP register definitions into separate file Marek Vasut
[not found] ` <1341555449-17507-1-git-send-email-marex-ynQEQJNshbs@public.gmane.org>
2012-07-06 6:17 ` [PATCH 06/10 V2] spi: Add SPI driver for mx233/mx28 Marek Vasut
2012-07-06 6:17 ` Marek Vasut
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