From patchwork Thu Aug 6 15:33:05 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Guenter Roeck X-Patchwork-Id: 11703559 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 8E12E722 for ; Thu, 6 Aug 2020 16:52:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E89A023119 for ; Thu, 6 Aug 2020 16:52:15 +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="m7aHHurS" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729339AbgHFQwB (ORCPT ); Thu, 6 Aug 2020 12:52:01 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43414 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729516AbgHFQvD (ORCPT ); Thu, 6 Aug 2020 12:51:03 -0400 Received: from mail-pf1-x441.google.com (mail-pf1-x441.google.com [IPv6:2607:f8b0:4864:20::441]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 73218C0086B3; Thu, 6 Aug 2020 08:33:18 -0700 (PDT) Received: by mail-pf1-x441.google.com with SMTP id r11so17255581pfl.11; Thu, 06 Aug 2020 08:33:18 -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; bh=OB49z5mjW0LWW4JF1oLw/U9qGTQogmAmaaexYlsEeUw=; b=m7aHHurSz7uvNcMNReeucg84mWKcscHNcmgJuLIIEgFG4hxSY6p8emZ8iiBLZU/SjU hnpDSG6rOqZL5ObYwMcDzUPqcKMrVziaFBtLZEyIGIPaKBYhG/nCZFPxWmaHFLTey134 B+Y45WUbfnQa99OlAw+RhZgOe7H+WYQwrwwu4UyqG8OZN+UMxfOagz/oO4Ip9YekWoH0 zuew55ms00TRlcuHveJKjLHunhcFXF/IhdiG7UuGivLBYZy8ShKzchCJUTkZ1C0DW8uG KHFjJYWhwx15gMR1fMcEwMoLLLPtsztdq/zWKAor2CJGnH8q7XibLdKD7IyKA7XZD6T/ B4HQ== 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; bh=OB49z5mjW0LWW4JF1oLw/U9qGTQogmAmaaexYlsEeUw=; b=dJ6HTEaIrc13Nx6W3KAj73IzHkIf8Gx4zrD7YHdWZCKvLFAvWVsP5I9KOTUt1EOXpA Hg6bbicmgIZ9xOJFhQULl/Tky5IjkA9ZDKJW9uaay9UPdr/fgo8KonK1dyFMAJY9NX9+ Q5U23auz/RE1enMF/KQDG60FKcjVvPg9fGoanqaim9ALhG1UG5/koNtGnNjR25DbSC85 6SOF/zhA+t50Ryi4ND+i3CAx77+l4vPUA5u9+ntnfN3K0icJqwC0q53mhf0d0LIzHJlv PBSJSKlgD3eaiYrTC5FMs2YxFV6OBgXEpH7pJfOAGSApOC+lUaHhLw6pKzjsQTyk/bQo KN/Q== X-Gm-Message-State: AOAM5322hHHkmylZQawG3M74Geau7u2AhPdce9D+e3Dhr7VidwxGdWTx 5oY06ZiV9l+W22yazmnZ/2I= X-Google-Smtp-Source: ABdhPJxiJvfAbC9f+jE+gjdTyrvBQXJFfHAlNRMm9oer2udDGpn+6J5NittGKv7K821x1r9QYXU9bA== X-Received: by 2002:a63:1a49:: with SMTP id a9mr7834508pgm.110.1596727998029; Thu, 06 Aug 2020 08:33:18 -0700 (PDT) Received: from localhost ([2600:1700:e321:62f0:329c:23ff:fee3:9d7c]) by smtp.gmail.com with ESMTPSA id 207sm8479732pfz.203.2020.08.06.08.33.17 (version=TLS1_2 cipher=ECDHE-ECDSA-CHACHA20-POLY1305 bits=256/256); Thu, 06 Aug 2020 08:33:17 -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 , Brian Norris , 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 Subject: [PATCH v4 4/7] pwm: cros-ec: Accept more error codes from cros_ec_cmd_xfer_status Date: Thu, 6 Aug 2020 08:33:05 -0700 Message-Id: <20200806153308.204605-5-linux@roeck-us.net> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20200806153308.204605-1-linux@roeck-us.net> References: <20200806153308.204605-1-linux@roeck-us.net> 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 Signed-off-by: Guenter Roeck Acked-by: Uwe Kleine-König --- 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;