From patchwork Tue Jun 2 00:19:54 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Tony Lindgren X-Patchwork-Id: 199677 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED, USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6F91BC433E0 for ; Tue, 2 Jun 2020 00:20:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 537A4207ED for ; Tue, 2 Jun 2020 00:20:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1725841AbgFBAUA (ORCPT ); Mon, 1 Jun 2020 20:20:00 -0400 Received: from muru.com ([72.249.23.125]:56666 "EHLO muru.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725446AbgFBAT7 (ORCPT ); Mon, 1 Jun 2020 20:19:59 -0400 Received: from hillo.muru.com (localhost [127.0.0.1]) by muru.com (Postfix) with ESMTP id 4219C804F; Tue, 2 Jun 2020 00:20:50 +0000 (UTC) From: Tony Lindgren To: linux-omap@vger.kernel.org Cc: =?utf-8?q?Beno=C3=AEt_Cousson?= , devicetree@vger.kernel.org, maemo-leste@lists.dyne.org, Merlijn Wajer , Pavel Machek , Sebastian Reichel Subject: [PATCH] ARM: dts: omap4-droid4: Fix spi configuration and increase rate Date: Mon, 1 Jun 2020 17:19:54 -0700 Message-Id: <20200602001954.30736-1-tony@atomide.com> X-Mailer: git-send-email 2.26.2 MIME-Version: 1.0 Sender: devicetree-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org We can currently sometimes get "RXS timed out" errors and "EOT timed out" errors with spi transfers. These errors can be made easy to reproduce by reading the cpcap iio values in a loop while keeping the CPUs busy by also reading /dev/urandom. The "RXS timed out" errors we can fix by adding spi-cpol and spi-cpha in addition to the spi-cs-high property we already have. The "EOT timed out" errors we can fix by increasing the spi clock rate to 9.6 MHz. Looks similar MC13783 PMIC says it works at spi clock rates up to 20 MHz, so let's assume we can pick any rate up to 20 MHz also for cpcap. Cc: maemo-leste@lists.dyne.org Cc: Merlijn Wajer Cc: Pavel Machek Cc: Sebastian Reichel Signed-off-by: Tony Lindgren --- arch/arm/boot/dts/motorola-cpcap-mapphone.dtsi | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/arch/arm/boot/dts/motorola-cpcap-mapphone.dtsi b/arch/arm/boot/dts/motorola-cpcap-mapphone.dtsi --- a/arch/arm/boot/dts/motorola-cpcap-mapphone.dtsi +++ b/arch/arm/boot/dts/motorola-cpcap-mapphone.dtsi @@ -13,8 +13,10 @@ cpcap: pmic@0 { #interrupt-cells = <2>; #address-cells = <1>; #size-cells = <0>; - spi-max-frequency = <3000000>; + spi-max-frequency = <9600000>; spi-cs-high; + spi-cpol; + spi-cpha; cpcap_adc: adc { compatible = "motorola,mapphone-cpcap-adc";