From patchwork Fri Jun 21 05:56:12 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: girishks2000@gmail.com X-Patchwork-Id: 2760211 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork1.web.kernel.org (Postfix) with ESMTP id A21AE9F39E for ; Fri, 21 Jun 2013 05:57:54 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id AEF0820173 for ; Fri, 21 Jun 2013 05:57:53 +0000 (UTC) Received: from casper.infradead.org (casper.infradead.org [85.118.1.10]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 41CAF20171 for ; Fri, 21 Jun 2013 05:57:52 +0000 (UTC) Received: from merlin.infradead.org ([2001:4978:20e::2]) by casper.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1UpuLU-0007yM-Pa; Fri, 21 Jun 2013 05:57:17 +0000 Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1UpuLO-0000Nc-V1; Fri, 21 Jun 2013 05:57:10 +0000 Received: from mail-pb0-x233.google.com ([2607:f8b0:400e:c01::233]) by merlin.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1UpuLB-0000Le-Ov for linux-arm-kernel@lists.infradead.org; Fri, 21 Jun 2013 05:56:59 +0000 Received: by mail-pb0-f51.google.com with SMTP id um15so7241918pbc.38 for ; Thu, 20 Jun 2013 22:56:35 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=from:to:cc:subject:date:message-id:x-mailer:in-reply-to:references; bh=SzUYUGeVGawCLqmZIAfsxVM1E0foLcGPYauno9T7DNM=; b=GtANYPgA9bi4JnzAaOLu4H4azTZDlC7rIArF3QZhhm2SKa3fV8tnOrRoPZv8uFX8a6 mgh8JtCz3dK+54/dN+p01UyGEZADsFfFsW6MMwioYXTkJVNZUqM2Za6GcC7e/mr6EgEB Pc8rgLN0hIWeuMsaXb359J/9TlUBFNiBbbq2nNei+cc20BWRnZXTabynKDswkHPzQyqv TEcafriEGug3U9dal9Y4NktQcEaQW4A41ynEqjkpivvFzor/7VADPQJlWk6tM7HT9Ocm R0HbgI/rC+o6Qixx0xNmzTgG1htVv5RsHKe5YCcHCJeSiccCrfpY2zyTsA3UKKG81EH1 gd2A== X-Received: by 10.68.194.169 with SMTP id hx9mr10459040pbc.210.1371794195887; Thu, 20 Jun 2013 22:56:35 -0700 (PDT) Received: from localhost.localdomain ([115.113.119.130]) by mx.google.com with ESMTPSA id re16sm4140496pac.16.2013.06.20.22.56.31 for (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Thu, 20 Jun 2013 22:56:34 -0700 (PDT) From: Girish K S To: spi-devel-general@lists.sourceforge.net, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org Subject: [PATCH 1/2] spi: s3c64xx: Added provision for dedicated cs pin Date: Fri, 21 Jun 2013 11:26:12 +0530 Message-Id: <1371794173-27266-2-git-send-email-ks.giri@samsung.com> X-Mailer: git-send-email 1.7.5.4 In-Reply-To: <1371794173-27266-1-git-send-email-ks.giri@samsung.com> References: <1371794173-27266-1-git-send-email-ks.giri@samsung.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20130621_015657_962876_7F5DB2C9 X-CRM114-Status: GOOD ( 18.59 ) X-Spam-Score: -1.8 (-) Cc: broonie@kernel.org, Girish K S X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Spam-Status: No, score=-5.6 required=5.0 tests=BAYES_00, DKIM_ADSP_CUSTOM_MED, DKIM_SIGNED, FREEMAIL_FROM, RCVD_IN_DNSWL_MED, RP_MATCHES_RCVD, T_DKIM_INVALID, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP From: Girish K S The existing driver supports gpio based /cs signal. For controller's that have one device per controller, the slave device's /cs signal might be internally controlled by the chip select bit of slave select register. They are not externally asserted/deasserted using gpio pin. This patch adds support for controllers with dedicated /cs pin. if "cs-gpio" property doesnt exist in a spi dts node, the controller would treat the /cs pin as dedicated. Signed-off-by: Girish K S --- drivers/spi/spi-s3c64xx.c | 34 ++++++++++++++++++++++++++-------- 1 files changed, 26 insertions(+), 8 deletions(-) diff --git a/drivers/spi/spi-s3c64xx.c b/drivers/spi/spi-s3c64xx.c index 0a80692..3744321 100644 --- a/drivers/spi/spi-s3c64xx.c +++ b/drivers/spi/spi-s3c64xx.c @@ -208,6 +208,7 @@ struct s3c64xx_spi_driver_data { struct s3c64xx_spi_port_config *port_conf; unsigned int port_id; unsigned long gpios[4]; + bool cs_gpio; }; static void flush_fifo(struct s3c64xx_spi_driver_data *sdd) @@ -570,14 +571,16 @@ static inline void enable_cs(struct s3c64xx_spi_driver_data *sdd, if (sdd->tgl_spi != spi) { /* if last mssg on diff device */ /* Deselect the last toggled device */ cs = sdd->tgl_spi->controller_data; - gpio_set_value(cs->line, - spi->mode & SPI_CS_HIGH ? 0 : 1); + if (sdd->cs_gpio) + gpio_set_value(cs->line, + spi->mode & SPI_CS_HIGH ? 0 : 1); } sdd->tgl_spi = NULL; } cs = spi->controller_data; - gpio_set_value(cs->line, spi->mode & SPI_CS_HIGH ? 1 : 0); + if (sdd->cs_gpio) + gpio_set_value(cs->line, spi->mode & SPI_CS_HIGH ? 1 : 0); /* Start the signals */ writel(0, sdd->regs + S3C64XX_SPI_SLAVE_SEL); @@ -709,7 +712,8 @@ static inline void disable_cs(struct s3c64xx_spi_driver_data *sdd, if (sdd->tgl_spi == spi) sdd->tgl_spi = NULL; - gpio_set_value(cs->line, spi->mode & SPI_CS_HIGH ? 0 : 1); + if (sdd->cs_gpio) + gpio_set_value(cs->line, spi->mode & SPI_CS_HIGH ? 0 : 1); /* Quiese the signals */ writel(S3C64XX_SPI_SLAVE_SIG_INACT, sdd->regs + S3C64XX_SPI_SLAVE_SEL); @@ -997,8 +1001,10 @@ static struct s3c64xx_spi_csinfo *s3c64xx_get_slave_ctrldata( { struct s3c64xx_spi_csinfo *cs; struct device_node *slave_np, *data_np = NULL; + struct s3c64xx_spi_driver_data *sdd; u32 fb_delay = 0; + sdd = spi_master_get_devdata(spi->master); slave_np = spi->dev.of_node; if (!slave_np) { dev_err(&spi->dev, "device node not found\n"); @@ -1018,7 +1024,10 @@ static struct s3c64xx_spi_csinfo *s3c64xx_get_slave_ctrldata( return ERR_PTR(-ENOMEM); } - cs->line = of_get_named_gpio(data_np, "cs-gpio", 0); + /* The CS line is asserted/deasserted by the gpio pin */ + if (sdd->cs_gpio) + cs->line = of_get_named_gpio(data_np, "cs-gpio", 0); + if (!gpio_is_valid(cs->line)) { dev_err(&spi->dev, "chip select gpio is not specified or invalid\n"); kfree(cs); @@ -1058,7 +1067,8 @@ static int s3c64xx_spi_setup(struct spi_device *spi) return -ENODEV; } - if (!spi_get_ctldata(spi)) { + /* Request gpio only if cs line is asserted by gpio pins */ + if (sdd->cs_gpio) { err = gpio_request_one(cs->line, GPIOF_OUT_INIT_HIGH, dev_name(&spi->dev)); if (err) { @@ -1067,9 +1077,11 @@ static int s3c64xx_spi_setup(struct spi_device *spi) cs->line, err); goto err_gpio_req; } - spi_set_ctldata(spi, cs); } + if (!spi_get_ctldata(spi)) + spi_set_ctldata(spi, cs); + sci = sdd->cntrlr_info; spin_lock_irqsave(&sdd->lock, flags); @@ -1147,8 +1159,10 @@ err_gpio_req: static void s3c64xx_spi_cleanup(struct spi_device *spi) { struct s3c64xx_spi_csinfo *cs = spi_get_ctldata(spi); + struct s3c64xx_spi_driver_data *sdd; - if (cs) { + sdd = spi_master_get_devdata(spi->master); + if (cs && sdd->cs_gpio) { gpio_free(cs->line); if (spi->dev.of_node) kfree(cs); @@ -1325,7 +1339,11 @@ static int s3c64xx_spi_probe(struct platform_device *pdev) sdd->cntrlr_info = sci; sdd->pdev = pdev; sdd->sfr_start = mem_res->start; + sdd->cs_gpio = true; if (pdev->dev.of_node) { + if (!of_find_property(pdev->dev.of_node, "cs-gpio", NULL)) + sdd->cs_gpio = false; + ret = of_alias_get_id(pdev->dev.of_node, "spi"); if (ret < 0) { dev_err(&pdev->dev, "failed to get alias id, errno %d\n",