From patchwork Tue Dec 4 07:53:48 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Wenyou Yang X-Patchwork-Id: 1836571 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-process-083081@patchwork1.kernel.org Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) by patchwork1.kernel.org (Postfix) with ESMTP id 36AF53FC71 for ; Tue, 4 Dec 2012 08:03:03 +0000 (UTC) Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.76 #1 (Red Hat Linux)) id 1TfnPg-0006vh-ED; Tue, 04 Dec 2012 07:59:32 +0000 Received: from casper.infradead.org ([2001:770:15f::2]) by merlin.infradead.org with esmtps (Exim 4.76 #1 (Red Hat Linux)) id 1TfnOy-0006gL-5P for linux-arm-kernel@merlin.infradead.org; Tue, 04 Dec 2012 07:58:48 +0000 Received: from newsmtp5.atmel.com ([204.2.163.5] helo=sjogate2.atmel.com) by casper.infradead.org with esmtp (Exim 4.76 #1 (Red Hat Linux)) id 1TfnOu-0000HV-OO for linux-arm-kernel@lists.infradead.org; Tue, 04 Dec 2012 07:58:46 +0000 Received: from penbh01.corp.atmel.com ([10.168.5.31]) by sjogate2.atmel.com (8.13.6/8.13.6) with ESMTP id qB47r9SA014424; Mon, 3 Dec 2012 23:53:10 -0800 (PST) Received: from penmb01.corp.atmel.com ([10.168.5.33]) by penbh01.corp.atmel.com with Microsoft SMTPSVC(6.0.3790.3959); Tue, 4 Dec 2012 15:58:20 +0800 Received: from shaarm01.corp.atmel.com ([10.217.6.34]) by penmb01.corp.atmel.com with Microsoft SMTPSVC(6.0.3790.3959); Tue, 4 Dec 2012 15:58:18 +0800 From: Wenyou Yang To: linux-arm-kernel@lists.infradead.org Subject: [v2 PATCH 02/14] of_spi: add generic binding support to specify cs gpio Date: Tue, 4 Dec 2012 15:53:48 +0800 Message-Id: <1354607640-13229-3-git-send-email-wenyou.yang@atmel.com> X-Mailer: git-send-email 1.7.9.5 In-Reply-To: <1354607640-13229-1-git-send-email-wenyou.yang@atmel.com> References: <1354607640-13229-1-git-send-email-wenyou.yang@atmel.com> X-OriginalArrivalTime: 04 Dec 2012 07:58:18.0624 (UTC) FILETIME=[1F518000:01CDD1F5] X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20121204_075845_153144_67A0B1C2 X-CRM114-Status: GOOD ( 27.66 ) X-Spam-Score: 0.5 (/) X-Spam-Report: SpamAssassin version 3.3.2 on casper.infradead.org summary: Content analysis details: (0.5 points, 5.0 required) pts rule name description ---- ---------------------- -------------------------------------------------- 3.0 KHOP_BIG_TO_CC Sent to 10+ recipients instaed of Bcc or a list -0.0 SPF_PASS SPF: sender matches SPF record -0.6 RP_MATCHES_RCVD Envelope sender domain matches handover relay domain -1.9 BAYES_00 BODY: Bayes spam probability is 0 to 1% [score: 0.0000] Cc: richard.genoud@gmail.com, JM.Lin@atmel.com, nicolas.ferre@atmel.com, linux-kernel@vger.kernel.org, rob.herring@calxeda.com, wenyou.yang@atmel.com, grant.likely@secretlab.ca, rob@landley.net, spi-devel-general@lists.sourceforge.net, plagnioj@jcrosoft.com, devicetree-discuss@lists.ozlabs.org X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Sender: linux-arm-kernel-bounces@lists.infradead.org Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org From: Jean-Christophe PLAGNIOL-VILLARD This will allow to use gpio for chip select with no modification in the driver binding When use the cs-gpios, the gpio number will be passed via the cs_gpio field and the number of chip select will automatically increased. Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD Cc: devicetree-discuss@lists.ozlabs.org Cc: spi-devel-general@lists.sourceforge.net Cc: grant.likely@secretlab.ca Cc: rob.herring@calxeda.com Cc: rob@landley.net Cc: richard.genoud@gmail.com --- Hi, Richard, This patch based on the original patch from Jean-Christophe, [PATCH] of_spi: add generic binding support to specify cs gpio and merge the patch from Richard Genoud, [PATCH] [BUG] SPI: array out of bound => no CS Could you sign your signature in this patch? Best Regards, Wenyou Yang Documentation/devicetree/bindings/spi/spi-bus.txt | 6 +++ drivers/spi/spi.c | 55 +++++++++++++++++++-- include/linux/spi/spi.h | 3 ++ 3 files changed, 61 insertions(+), 3 deletions(-) diff --git a/Documentation/devicetree/bindings/spi/spi-bus.txt b/Documentation/devicetree/bindings/spi/spi-bus.txt index d2c33d0..7f59ae30 100644 --- a/Documentation/devicetree/bindings/spi/spi-bus.txt +++ b/Documentation/devicetree/bindings/spi/spi-bus.txt @@ -12,6 +12,7 @@ The SPI master node requires the following properties: - #size-cells - should be zero. - compatible - name of SPI bus controller following generic names recommended practice. +- cs-gpios - (optional) gpios chip select. No other properties are required in the SPI bus node. It is assumed that a driver for an SPI bus device will understand that it is an SPI bus. However, the binding does not attempt to define the specific method for @@ -21,6 +22,8 @@ assumption that board specific platform code will be used to manage chip selects. Individual drivers can define additional properties to support describing the chip select layout. +If cs-gpios is used the number of chip select will automatically increased. + Optional property: - num-cs : total number of chipselects @@ -37,6 +40,9 @@ contain the following properties. - spi-cs-high - (optional) Empty property indicating device requires chip select active high +If a gpio chipselect is used for the SPI slave the gpio number will be passed +via the controller_data + SPI example for an MPC5200 SPI bus: spi@f00 { #address-cells = <1>; diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c index 84c2861..74e6577 100644 --- a/drivers/spi/spi.c +++ b/drivers/spi/spi.c @@ -30,6 +30,7 @@ #include #include #include +#include #include #include #include @@ -327,6 +328,7 @@ struct spi_device *spi_alloc_device(struct spi_master *master) spi->dev.parent = &master->dev; spi->dev.bus = &spi_bus_type; spi->dev.release = spidev_release; + spi->cs_gpio = -EINVAL; device_initialize(&spi->dev); return spi; } @@ -344,15 +346,16 @@ EXPORT_SYMBOL_GPL(spi_alloc_device); int spi_add_device(struct spi_device *spi) { static DEFINE_MUTEX(spi_add_lock); - struct device *dev = spi->master->dev.parent; + struct spi_master *master = spi->master; + struct device *dev = master->dev.parent; struct device *d; int status; /* Chipselects are numbered 0..max; validate. */ - if (spi->chip_select >= spi->master->num_chipselect) { + if (spi->chip_select >= master->num_chipselect) { dev_err(dev, "cs%d >= max %d\n", spi->chip_select, - spi->master->num_chipselect); + master->num_chipselect); return -EINVAL; } @@ -376,6 +379,9 @@ int spi_add_device(struct spi_device *spi) goto done; } + if (master->cs_gpios) + spi->cs_gpio = master->cs_gpios[spi->chip_select]; + /* Drivers may modify this initial i/o setup, but will * normally rely on the device being setup. Devices * using SPI_CS_HIGH can't coexist well otherwise... @@ -946,6 +952,45 @@ struct spi_master *spi_alloc_master(struct device *dev, unsigned size) } EXPORT_SYMBOL_GPL(spi_alloc_master); +#ifdef CONFIG_OF +static int of_spi_register_master(struct spi_master *master) +{ + int nb, i; + int *cs; + struct device_node *np = master->dev.of_node; + + if (!np) + return 0; + + nb = of_gpio_named_count(np, "cs-gpios"); + + if (nb < 1) + return 0; + + cs = devm_kzalloc(&master->dev, + sizeof(int) * (master->num_chipselect + nb), + GFP_KERNEL); + master->cs_gpios = cs; + + if (!master->cs_gpios) + return -ENOMEM; + + memset(cs, -EINVAL, master->num_chipselect); + cs += master->num_chipselect; + master->num_chipselect += nb; + + for (i = 0; i < nb; i++) + cs[i] = of_get_named_gpio(np, "cs-gpios", i); + + return 0; +} +#else +static int of_spi_register_master(struct spi_master *master) +{ + return 0; +} +#endif + /** * spi_register_master - register SPI master controller * @master: initialized master, originally from spi_alloc_master() @@ -977,6 +1022,10 @@ int spi_register_master(struct spi_master *master) if (!dev) return -ENODEV; + status = of_spi_register_master(master); + if (status) + return status; + /* even if it's just one always-selected device, there must * be at least one chipselect */ diff --git a/include/linux/spi/spi.h b/include/linux/spi/spi.h index fa702ae..f629189 100644 --- a/include/linux/spi/spi.h +++ b/include/linux/spi/spi.h @@ -90,6 +90,7 @@ struct spi_device { void *controller_state; void *controller_data; char modalias[SPI_NAME_SIZE]; + int cs_gpio; /* chip select gpio */ /* * likely need more hooks for more protocol options affecting how @@ -362,6 +363,8 @@ struct spi_master { int (*transfer_one_message)(struct spi_master *master, struct spi_message *mesg); int (*unprepare_transfer_hardware)(struct spi_master *master); + /* gpio chip select */ + int *cs_gpios; }; static inline void *spi_master_get_devdata(struct spi_master *master)