From patchwork Thu Nov 17 10:52:42 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Tudor Ambarus X-Patchwork-Id: 13046572 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 76A8FC43217 for ; Thu, 17 Nov 2022 10:53:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239622AbiKQKxn (ORCPT ); Thu, 17 Nov 2022 05:53:43 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42416 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234058AbiKQKxG (ORCPT ); Thu, 17 Nov 2022 05:53:06 -0500 Received: from esa.microchip.iphmx.com (esa.microchip.iphmx.com [68.232.154.123]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D51275E9E5; Thu, 17 Nov 2022 02:52:57 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=microchip.com; i=@microchip.com; q=dns/txt; s=mchp; t=1668682377; x=1700218377; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=gNtn9WfsbwYVLh4+RkqUoRwPVNMtyYltmpBOWMDfWsw=; b=sRHyVYoFhEXKVU58uS4G4lS9tKNIIeHwI7o5d1sT6uHzqZotaqPR8JgY GE5VuxTTjqUNDlJ7/9y165D2U/voNyLsmf+U3qT8CFObA+3zkyl9c3W5D RNxPujqFzSGS1bPWzk2/+YPG/i0pxiKfMOOfvqJKVv4EfG07tk88kcIS2 DK8gje8bJKJAPN5UtIPWxHw2ReVTh8UX8OUwjDkEO2rJNEfgVQerhu7q9 UzkSE6EIshgToMfLPyy+OoqLBxcQSfn2a1IbIA7Zw9LnnYhBP/4TIwle+ Z4s8nKRzsya8PHEyqlK+GFkauoQBzKNe+bAeWCLcWcL7EQ3YRCOwHnvgF A==; X-IronPort-AV: E=Sophos;i="5.96,171,1665471600"; d="scan'208";a="123873129" Received: from unknown (HELO email.microchip.com) ([170.129.1.10]) by esa6.microchip.iphmx.com with ESMTP/TLS/AES256-SHA256; 17 Nov 2022 03:52:56 -0700 Received: from chn-vm-ex02.mchp-main.com (10.10.87.72) by chn-vm-ex02.mchp-main.com (10.10.87.72) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.12; Thu, 17 Nov 2022 03:52:56 -0700 Received: from ROB-ULT-M18064N.mchp-main.com (10.10.115.15) by chn-vm-ex02.mchp-main.com (10.10.85.144) with Microsoft SMTP Server id 15.1.2507.12 via Frontend Transport; Thu, 17 Nov 2022 03:52:53 -0700 From: Tudor Ambarus To: , , , , , CC: , , , , , Tudor Ambarus Subject: [PATCH 1/8] spi: dt-bindings: Introduce spi-cs-setup-ns property Date: Thu, 17 Nov 2022 12:52:42 +0200 Message-ID: <20221117105249.115649-2-tudor.ambarus@microchip.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20221117105249.115649-1-tudor.ambarus@microchip.com> References: <20221117105249.115649-1-tudor.ambarus@microchip.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-spi@vger.kernel.org SPI NOR flashes have specific cs-setup time requirements without which they can't work at frequencies close to their maximum supported frequency, as they miss the first bits of the instruction command. Unrecognized commands are ignored, thus the flash will be unresponsive. Introduce the spi-cs-setup-ns property to allow spi devices to specify their cs setup time. Signed-off-by: Tudor Ambarus --- .../devicetree/bindings/spi/spi-peripheral-props.yaml | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/Documentation/devicetree/bindings/spi/spi-peripheral-props.yaml b/Documentation/devicetree/bindings/spi/spi-peripheral-props.yaml index dca677f9e1b9..ead2cccf658f 100644 --- a/Documentation/devicetree/bindings/spi/spi-peripheral-props.yaml +++ b/Documentation/devicetree/bindings/spi/spi-peripheral-props.yaml @@ -44,6 +44,11 @@ properties: description: Maximum SPI clocking speed of the device in Hz. + spi-cs-setup-ns: + description: + Delay in nanosecods to be introduced by the controller after CS is + asserted. + spi-rx-bus-width: description: Bus width to the SPI bus used for read transfers.