From patchwork Sat Aug 22 15:08:54 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Guenter Roeck X-Patchwork-Id: 11731175 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 79B401575 for ; Sat, 22 Aug 2020 15:09:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 559A72072D for ; Sat, 22 Aug 2020 15:09:13 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="TreoCnNR" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728211AbgHVPJK (ORCPT ); Sat, 22 Aug 2020 11:09:10 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46590 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728196AbgHVPJJ (ORCPT ); Sat, 22 Aug 2020 11:09:09 -0400 Received: from mail-pj1-x1043.google.com (mail-pj1-x1043.google.com [IPv6:2607:f8b0:4864:20::1043]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 98D0AC061575; Sat, 22 Aug 2020 08:09:08 -0700 (PDT) Received: by mail-pj1-x1043.google.com with SMTP id kr4so2091713pjb.2; Sat, 22 Aug 2020 08:09:08 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=sender:from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=aWfg/p1bEEsF9VR7qbKwXbT4prM1ax9SkBLPqSVouws=; b=TreoCnNRUV59m5H5mc54POb5e9AKUfujBJtw6CIU7DJ7TlGxX+yWWCP90io+UvOhtI 6lN6VARFlIqBKPqYLlaGNDPnM9Q3+Fsd5EiE77WcG1FjMNbhUiTgw+eHU9Odthuh81lh BY+V/CK+INs+HgCEm8drPMVSUzhSMeEGuR33FpIiedWXcilR1XxjcbF3SHrkRzPyH56f baurpXfeJMVOEuh5wP4ETfaQXhStCqc6nMOycfWwUbB7ksdW8nnvtGzXBBKHgb2FTwet 3BqxDuzR3/1LGrjg1flO1cB++9SUh1+CP3TNx9S7/0sxZxUkPvbe+FsBqSSJfHyMphfn oGiw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:from:to:cc:subject:date:message-id :in-reply-to:references:mime-version:content-transfer-encoding; bh=aWfg/p1bEEsF9VR7qbKwXbT4prM1ax9SkBLPqSVouws=; b=b9XiuoU01BLGuQCJyVU7COCO63YBASXCjsW+yLXpfiaadDIZAWLvIyOGXVF6Ua9Zi0 O0dl4j89f+7vKnWr7MXBPd5CBlChMVmynVrsXglu3q2Xypy3fJFwdmKiFhpo6xqit3P5 jOh6VmR12aEE++2BBzw5TlqWTwVC+PSemthapbl1LtwbHi/9cJjI7dL0EEZaODcBHMmh 5exK9XgJRa98DQRmoCL93dPa1hSrX0TxfhcOUxBVk9wTkYFSYR4DiC2KBgLNEU3jIebX MACGmRk6SBiVnmXi3cyi/2mRC6bXy1Q43zApustOTwepFICziL6DWL/2rTJX/BSg/WuT CqxQ== X-Gm-Message-State: AOAM530a2WubOv2eTbJYYvgmlyKjMt6OBlgTKiKlXrytfMOMr8nsERbb x9FPIS/3CN9WdEadDKYWY/U= X-Google-Smtp-Source: ABdhPJys2OLCfUIKzWTMevNyztH0683b7F8X4R7+XyRTVJJiiPVel4kLEjsxFqZHvK3QajGoT+87wA== X-Received: by 2002:a17:90b:154:: with SMTP id em20mr6778169pjb.173.1598108948143; Sat, 22 Aug 2020 08:09:08 -0700 (PDT) Received: from localhost ([2600:1700:e321:62f0:329c:23ff:fee3:9d7c]) by smtp.gmail.com with ESMTPSA id n18sm5066040pgd.91.2020.08.22.08.09.07 (version=TLS1_2 cipher=ECDHE-ECDSA-CHACHA20-POLY1305 bits=256/256); Sat, 22 Aug 2020 08:09:07 -0700 (PDT) From: Guenter Roeck To: Enric Balletbo i Serra Cc: Jonathan Cameron , Benson Leung , Dmitry Torokhov , Thierry Reding , =?utf-8?q?Uwe_Kleine-K=C3=B6nig?= , Lee Jones , Gwendal Grignou , Yu-Hsuan Hsu , Prashant Malani , linux-iio@vger.kernel.org, linux-input@vger.kernel.org, linux-pwm@vger.kernel.org, linux-kernel@vger.kernel.org, Guenter Roeck , Brian Norris Subject: [PATCH v5 4/7] pwm: cros-ec: Accept more error codes from cros_ec_cmd_xfer_status Date: Sat, 22 Aug 2020 08:08:54 -0700 Message-Id: <20200822150857.205775-5-linux@roeck-us.net> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20200822150857.205775-1-linux@roeck-us.net> References: <20200822150857.205775-1-linux@roeck-us.net> MIME-Version: 1.0 Sender: linux-input-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-input@vger.kernel.org Since commit c5cd2b47b203 ("platform/chrome: cros_ec_proto: Report command not supported") we can no longer assume that cros_ec_cmd_xfer_status() reports -EPROTO for all errors returned by the EC itself. A follow-up patch will change cros_ec_cmd_xfer_status() to report additional errors reported by the EC as distinguished Linux error codes. Handle this change by no longer assuming that only -EPROTO is used to report all errors returned by the EC itself. Instead, support both the old and the new error codes. Add a comment describing cros_ec_num_pwms() to explain its functionality. Cc: Gwendal Grignou Cc: Yu-Hsuan Hsu Cc: Prashant Malani Cc: Brian Norris Acked-by: Thierry Reding Acked-by: Uwe Kleine-König Signed-off-by: Guenter Roeck --- v5: Added Uwe's Acked-by: tag v4: Added comments describing cros_ec_num_pwms() in more detail Added Thierry's Acked-by: tag v3: Added patch drivers/pwm/pwm-cros-ec.c | 29 ++++++++++++++++++++++------- 1 file changed, 22 insertions(+), 7 deletions(-) diff --git a/drivers/pwm/pwm-cros-ec.c b/drivers/pwm/pwm-cros-ec.c index 09c08dee099e..94d3dff9b0e5 100644 --- a/drivers/pwm/pwm-cros-ec.c +++ b/drivers/pwm/pwm-cros-ec.c @@ -204,6 +204,11 @@ static const struct pwm_ops cros_ec_pwm_ops = { .owner = THIS_MODULE, }; +/* + * Determine the number of supported PWMs. The EC does not return the number + * of PWMs it supports directly, so we have to read the pwm duty cycle for + * subsequent channels until we get an error. + */ static int cros_ec_num_pwms(struct cros_ec_device *ec) { int i, ret; @@ -213,20 +218,30 @@ static int cros_ec_num_pwms(struct cros_ec_device *ec) u32 result = 0; ret = __cros_ec_pwm_get_duty(ec, i, &result); - /* We want to parse EC protocol errors */ - if (ret < 0 && !(ret == -EPROTO && result)) - return ret; - /* * We look for SUCCESS, INVALID_COMMAND, or INVALID_PARAM * responses; everything else is treated as an error. + * The EC error codes either map to -EOPNOTSUPP / -EINVAL, + * or -EPROTO is returned and the EC error is in the result + * field. Check for both. */ - if (result == EC_RES_INVALID_COMMAND) + switch (ret) { + case -EOPNOTSUPP: /* invalid command */ return -ENODEV; - else if (result == EC_RES_INVALID_PARAM) + case -EINVAL: /* invalid parameter */ return i; - else if (result) + case -EPROTO: + /* Old or new error return code: Handle both */ + if (result == EC_RES_INVALID_COMMAND) + return -ENODEV; + else if (result == EC_RES_INVALID_PARAM) + return i; return -EPROTO; + default: + if (ret < 0) + return ret; + break; + } } return U8_MAX;