From patchwork Thu Jun 30 12:15:53 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mark Brown X-Patchwork-Id: 9207353 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id BCDC960752 for ; Thu, 30 Jun 2016 12:18:46 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id ACE972867B for ; Thu, 30 Jun 2016 12:18:46 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id A11FF2867D; Thu, 30 Jun 2016 12:18:46 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=unavailable version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 169BD2867B for ; Thu, 30 Jun 2016 12:18:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752037AbcF3MQF (ORCPT ); Thu, 30 Jun 2016 08:16:05 -0400 Received: from mezzanine.sirena.org.uk ([106.187.55.193]:58626 "EHLO mezzanine.sirena.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751929AbcF3MQC (ORCPT ); Thu, 30 Jun 2016 08:16:02 -0400 Received: from [137.158.23.105] (helo=finisterre) by mezzanine.sirena.org.uk with esmtpsa (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.84_2) (envelope-from ) id 1bIasw-0000Lk-B9; Thu, 30 Jun 2016 12:15:59 +0000 Received: from broonie by finisterre with local (Exim 4.87) (envelope-from ) id 1bIasr-0001EN-6Z; Thu, 30 Jun 2016 13:15:53 +0100 From: Mark Brown To: Andi Shyti Cc: Mark Brown , Kukjin Kim , Krzysztof Kozlowski , Mark Brown , Jaehoon Chung , linux-arm-kernel@lists.infradead.org, linux-samsung-soc@vger.kernel.org, linux-spi@vger.kernel.org, linux-kernel@vger.kernel.org, Andi Shyti In-Reply-To: <1467081676-8442-3-git-send-email-andi.shyti@samsung.com> Message-Id: Date: Thu, 30 Jun 2016 13:15:53 +0100 X-SA-Exim-Connect-IP: 137.158.23.105 X-SA-Exim-Mail-From: broonie@sirena.org.uk Subject: Applied "spi: s3c64xx: consider the case when the CS line is not connected" to the spi tree X-SA-Exim-Version: 4.2.1 (built Mon, 26 Dec 2011 16:24:06 +0000) X-SA-Exim-Scanned: Yes (on mezzanine.sirena.org.uk) Sender: linux-spi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-spi@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP The patch spi: s3c64xx: consider the case when the CS line is not connected has been applied to the spi tree at git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi.git All being well this means that it will be integrated into the linux-next tree (usually sometime in the next 24 hours) and sent to Linus during the next merge window (or sooner if it is a bug fix), however if problems are discovered then the patch may be dropped or reverted. You may get further e-mails resulting from automated or manual testing and review of the tree, please engage with people reporting problems and send followup patches addressing any issues that are reported if needed. If any updates are required or you are submitting further changes they should be sent as incremental updates against current git, existing patches will not be replaced. Please add any relevant lists and maintainers to the CCs when replying to this mail. Thanks, Mark From a92e7c3d82a1313ab1954e5cdfd8f04efdb4ca78 Mon Sep 17 00:00:00 2001 From: Andi Shyti Date: Tue, 28 Jun 2016 11:41:12 +0900 Subject: [PATCH] spi: s3c64xx: consider the case when the CS line is not connected When the CS line is not connected, it is not needed to enable or disable the chip selection functionality from the s3c64xx devices in order to perform a transfer. Set the CS controller logically always enabled already during initialization (by writing '0' in the S3C64XX_SPI_SLAVE_SEL register) and never disable it. Signed-off-by: Andi Shyti Signed-off-by: Mark Brown --- Documentation/devicetree/bindings/spi/spi-samsung.txt | 3 +++ drivers/spi/spi-s3c64xx.c | 9 ++++++++- include/linux/platform_data/spi-s3c64xx.h | 1 + 3 files changed, 12 insertions(+), 1 deletion(-) diff --git a/Documentation/devicetree/bindings/spi/spi-samsung.txt b/Documentation/devicetree/bindings/spi/spi-samsung.txt index 6dbdeb3c361a..930bc7349271 100644 --- a/Documentation/devicetree/bindings/spi/spi-samsung.txt +++ b/Documentation/devicetree/bindings/spi/spi-samsung.txt @@ -40,6 +40,9 @@ Optional Board Specific Properties: - cs-gpios: should specify GPIOs used for chipselects (see spi-bus.txt) +- no-cs-readback: the CS line is disconnected, therefore the device should not + operate based on CS signalling. + SPI Controller specific data in SPI slave nodes: - The spi slave nodes should provide the following information which is required diff --git a/drivers/spi/spi-s3c64xx.c b/drivers/spi/spi-s3c64xx.c index 972367d5c7f2..14269b07804c 100644 --- a/drivers/spi/spi-s3c64xx.c +++ b/drivers/spi/spi-s3c64xx.c @@ -315,6 +315,9 @@ static void s3c64xx_spi_set_cs(struct spi_device *spi, bool enable) struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(spi->master); + if (sdd->cntrlr_info->no_cs) + return; + if (enable) { if (!(sdd->port_conf->quirks & S3C64XX_SPI_QUIRK_CS_AUTO)) { writel(0, sdd->regs + S3C64XX_SPI_SLAVE_SEL); @@ -960,7 +963,9 @@ static void s3c64xx_spi_hwinit(struct s3c64xx_spi_driver_data *sdd, int channel) sdd->cur_speed = 0; - if (!(sdd->port_conf->quirks & S3C64XX_SPI_QUIRK_CS_AUTO)) + if (sci->no_cs) + writel(0, sdd->regs + S3C64XX_SPI_SLAVE_SEL); + else if (!(sdd->port_conf->quirks & S3C64XX_SPI_QUIRK_CS_AUTO)) writel(S3C64XX_SPI_SLAVE_SIG_INACT, sdd->regs + S3C64XX_SPI_SLAVE_SEL); /* Disable Interrupts - we use Polling if not DMA mode */ @@ -1015,6 +1020,8 @@ static struct s3c64xx_spi_info *s3c64xx_spi_parse_dt(struct device *dev) sci->num_cs = temp; } + sci->no_cs = of_property_read_bool(dev->of_node, "broken-cs"); + return sci; } #else diff --git a/include/linux/platform_data/spi-s3c64xx.h b/include/linux/platform_data/spi-s3c64xx.h index fb5625bcca9a..5c1e21c87270 100644 --- a/include/linux/platform_data/spi-s3c64xx.h +++ b/include/linux/platform_data/spi-s3c64xx.h @@ -38,6 +38,7 @@ struct s3c64xx_spi_csinfo { struct s3c64xx_spi_info { int src_clk_nr; int num_cs; + bool no_cs; int (*cfg_gpio)(void); dma_filter_fn filter; void *dma_tx;