From patchwork Wed May 17 22:30:05 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Boerge Struempfel X-Patchwork-Id: 13245822 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0B56EC77B7A for ; Wed, 17 May 2023 22:30:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229595AbjEQWas (ORCPT ); Wed, 17 May 2023 18:30:48 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33972 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229456AbjEQWar (ORCPT ); Wed, 17 May 2023 18:30:47 -0400 Received: from mail-ej1-x62f.google.com (mail-ej1-x62f.google.com [IPv6:2a00:1450:4864:20::62f]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 064C659FD; Wed, 17 May 2023 15:30:44 -0700 (PDT) Received: by mail-ej1-x62f.google.com with SMTP id a640c23a62f3a-965fc25f009so235898466b.3; Wed, 17 May 2023 15:30:43 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20221208; t=1684362642; x=1686954642; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:from:to:cc:subject:date:message-id:reply-to; bh=1xvZgYgSWGaYso+rMNPq2umuAV7PxMbwVAnAP9WIPXc=; b=OZ9CGRQV1SeQ2kcD8yaOaISaKguhXnwPewhpm95OxfALiQ+94wbvi7qyuoi0EhMcLy o+NI1Sn59jiDT886nlK4v7x1q4a77uIZi+ov/J2+TjnGYFqn1zrCxMLAcHkOu3zz7DUL s5ihngf9Q/WBNpaqAkzRljMTUJqM4tb1vRBIudf4y7C/HK6xsN8KnpZsa0rKVWC+XlZa tZCwzhQB26iGoLJtIjxyUY/XFp07GqQPFncDfZU00Yq+MMWrwT3w+C6w5BJV5GHDm4Sj NUgosoE5MoADYEa4yRUGEe8ayujrc8enXF/10AnEFZWFU7ChbRhI+O5YQ6RLcacAfzqE Wnnw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1684362642; x=1686954642; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=1xvZgYgSWGaYso+rMNPq2umuAV7PxMbwVAnAP9WIPXc=; b=ftC1c/Fhx6P9Rs6d3kiDsFOtgOvFhT3wM/7wSZYLsfqQKW5ZekbHTSwNQt8aapyECl 5691XPHpvcqEX0VInzD3ehmvgSqizSa9fKPT41lCEe8qfER9KwIc6blbuHNE+42GeAIV W44NKYURnnVFJkJB4T5TPFUEhXET7JaPMNErm3II1si81Q5h+s4H2OFYHp44ijU4armX FTpqB5a+ckifK99GZzSrggRtawfFvQS2L/KQdSLDFxvyjQG5FbR0w9KKjwjE09nPbhMM u0muUzXCGJZdYLSpRvDGn8kPlK/oWHPwCUhV7w4QXTWN+YL9QxVOb3+3z2QJwZGmq5cA eLOw== X-Gm-Message-State: AC+VfDy/BhUodNcq/b2oUQv7MmzyYdRIVCEUDCwSO3NJWlyAUDO9Zo2w Fonjo36TCjX7BoGNlFAcv6w= X-Google-Smtp-Source: ACHHUZ6nai5aV4t2xJk7IyN+8Ad3ycGG5nCY8zPmux1AvlcXXVCpMuuuutAsIVKWGprRkefr8VzF4Q== X-Received: by 2002:a17:907:3e9c:b0:966:471c:2565 with SMTP id hs28-20020a1709073e9c00b00966471c2565mr37357809ejc.48.1684362642211; Wed, 17 May 2023 15:30:42 -0700 (PDT) Received: from wslxew193.fritz.box (p200300c78700c900633510ddc4028dcd.dip0.t-ipconnect.de. [2003:c7:8700:c900:6335:10dd:c402:8dcd]) by smtp.gmail.com with ESMTPSA id y14-20020a1709064b0e00b0095807ab4b57sm109327eju.178.2023.05.17.15.30.40 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 17 May 2023 15:30:41 -0700 (PDT) From: Boerge Struempfel Cc: boerge.struempfel@gmail.com, bstruempfel@ultratronik.de, andy.shevchenko@gmail.com, festevam@gmail.com, amit.kumar-mahapatra@amd.com, broonie@kernel.org, Shawn Guo , Sascha Hauer , Pengutronix Kernel Team , NXP Linux Team , linux-spi@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Subject: [PATCH v4 1/3] spi: add SPI_MOSI_IDLE_LOW mode bit Date: Thu, 18 May 2023 00:30:05 +0200 Message-Id: <20230517223007.178432-1-boerge.struempfel@gmail.com> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 To: unlisted-recipients:; (no To-header on input) Precedence: bulk List-ID: X-Mailing-List: linux-spi@vger.kernel.org Some spi controller switch the mosi line to high, whenever they are idle. This may not be desired in all use cases. For example neopixel leds can get confused and flicker due to misinterpreting the idle state. Therefore, we introduce a new spi-mode bit, with which the idle behaviour can be overwritten on a per device basis. Signed-off-by: Boerge Struempfel Link for versions: v1 and v2: https://lore.kernel.org/linux-spi/20230511135632.78344-1-bstruempfel@ultratronik.de/ v3: https://lore.kernel.org/linux-spi/20230517103007.26287-1-boerge.struempfel@gmail.com/T/#t Changes from V3: - Added missing paranthesis which caused builderrors Changes from V2: - Removed the device-tree binding since this should not be managed by the DT but by the device itself. - Replaced all occurences of spi->chip_select with the corresponding macro spi_get_chipselect(spi,0) Changes from V1: - Added patch, introducing the new devicetree binding flag - Split the generic spi part of the patch from the imx-spi specific part - Replaced SPI_CPOL and SPI_CPHA by the combined SPI_MODE_X_MASK bit in the imx-spi.c modebits. - Added the SPI_MOSI_IDLE_LOW bit to spidev Signed-off-by: Your name --- include/uapi/linux/spi/spi.h | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/include/uapi/linux/spi/spi.h b/include/uapi/linux/spi/spi.h index 9d5f58059703..ca56e477d161 100644 --- a/include/uapi/linux/spi/spi.h +++ b/include/uapi/linux/spi/spi.h @@ -28,6 +28,7 @@ #define SPI_RX_OCTAL _BITUL(14) /* receive with 8 wires */ #define SPI_3WIRE_HIZ _BITUL(15) /* high impedance turnaround */ #define SPI_RX_CPHA_FLIP _BITUL(16) /* flip CPHA on Rx only xfer */ +#define SPI_MOSI_IDLE_LOW _BITUL(17) /* leave mosi line low when idle */ /* * All the bits defined above should be covered by SPI_MODE_USER_MASK. @@ -37,6 +38,6 @@ * These bits must not overlap. A static assert check should make sure of that. * If adding extra bits, make sure to increase the bit index below as well. */ -#define SPI_MODE_USER_MASK (_BITUL(17) - 1) +#define SPI_MODE_USER_MASK (_BITUL(18) - 1) #endif /* _UAPI_SPI_H */