From mboxrd@z Thu Jan 1 00:00:00 1970 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=-15.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,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 A9094C433B4 for ; Wed, 19 May 2021 22:29:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8CDC461353 for ; Wed, 19 May 2021 22:29:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229999AbhESWbO (ORCPT ); Wed, 19 May 2021 18:31:14 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38122 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230020AbhESWbM (ORCPT ); Wed, 19 May 2021 18:31:12 -0400 Received: from mail-qk1-x72b.google.com (mail-qk1-x72b.google.com [IPv6:2607:f8b0:4864:20::72b]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E87DBC06175F; Wed, 19 May 2021 15:29:50 -0700 (PDT) Received: by mail-qk1-x72b.google.com with SMTP id k4so3291005qkd.0; Wed, 19 May 2021 15:29:50 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=+oLkd2BFmvyOKIIVIKSB47lAlzpITnkbcma+rS4i+f4=; b=M7/uMs4uOWPQGG6ys73fVHklBVvxYef5A4uyjv1faBK/y2DN1Brj/R7NXfO+zfWlnO I2/a4jS61+IXZyhdWvvb1MawlJJ5n2zb3YMshljbqaxg46ABfoovgVdY+hyrXxzkQEYW dGJ3njUH0hDxrGHtoFaz2tkCNHKnMitxerREaM0PatOc9Lzdv8BfaCXHvgJMSFx5a8ui OVW8Gd+oICZOvm6YK93p8rccxDZKPLa0sS/vdC+Cytm1c9qvUTDdaNvJVwhSZe5x3Owr WIwSIBk/BSUwNk85pf/4rsOwfa0WLHO6PSx9BoXTF6PX5YevEf7UGI8uUQR+Id4AnUfl dl+g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=+oLkd2BFmvyOKIIVIKSB47lAlzpITnkbcma+rS4i+f4=; b=hGw26CoKsw2swE9k+izRAG2/X5uBQZa/DN4iVqXKvX/wbx1N5n6qoxwnfm+RYKrUin jIKgVSArMlS1SO7cbtAOUttmUOENiu806dvs5EknKI5fCcSIEA0zvSpYrTqG5zQ/FoM6 RLgspOctSy+mhk3Fmu/5P4wd7aPr5F+NNap84RBIvdNOwQkQHyM1iBtAqYBCcZ0w66GC t2Gtp055HFHpd5WE04MmT5UIQT2vLADlX7GSleApXdmi+r6VfgrDQmI4Tz/vuu7cExBI PazxufP51qsFSIj16MnMu+xBdJg8Ja2PXizNJqni/Ae7x4DbaNgzUZfPHzgs0ertfRZc WuOQ== X-Gm-Message-State: AOAM532b7oPtD7x4SIv0SWJWBoFYTbLndPbJquVjrQSCZKpdKr6jd0Ko 17xASq2U5wmv6lodh7RzjHc= X-Google-Smtp-Source: ABdhPJwABm3nKfiB4f+H0r4INFR7J+pQ9Nqli+Q29VJEKNsKIc7LYQpMFqKkC4VO//qoMJTKlBbZsg== X-Received: by 2002:a37:a4c1:: with SMTP id n184mr1716069qke.309.1621463390131; Wed, 19 May 2021 15:29:50 -0700 (PDT) Received: from LuizSampaio-PC.localdomain ([2804:214:8175:da27:c352:bf96:2102:fa64]) by smtp.gmail.com with ESMTPSA id d18sm823716qkc.28.2021.05.19.15.29.46 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 19 May 2021 15:29:49 -0700 (PDT) From: Luiz Sampaio To: zbr@ioremap.net Cc: corbet@lwn.net, rikard.falkeborn@gmail.com, gregkh@linuxfoundation.org, linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org, Luiz Sampaio Subject: [PATCH v8 5/6] w1: ds2438: adding support for reading page1 Date: Wed, 19 May 2021 19:30:45 -0300 Message-Id: <20210519223046.13798-6-sampaio.ime@gmail.com> X-Mailer: git-send-email 2.30.1 In-Reply-To: <20210519223046.13798-1-sampaio.ime@gmail.com> References: <20210409031533.442123-1-sampaio.ime@gmail.com> <20210519223046.13798-1-sampaio.ime@gmail.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Added a sysfs entry to support reading the page1 registers. This registers contain Elapsed Time Meter (ETM) data, which shows for how long the chip is on, as well as an Offset Register data, which can be used to calibrate the current measurement of the chip. Signed-off-by: Luiz Sampaio --- .../ABI/stable/sysfs-driver-w1_ds2438 | 6 +++ Documentation/w1/slaves/w1_ds2438.rst | 8 ++++ drivers/w1/slaves/w1_ds2438.c | 41 +++++++++++++++++++ 3 files changed, 55 insertions(+) create mode 100644 Documentation/ABI/stable/sysfs-driver-w1_ds2438 diff --git a/Documentation/ABI/stable/sysfs-driver-w1_ds2438 b/Documentation/ABI/stable/sysfs-driver-w1_ds2438 new file mode 100644 index 000000000000..fa47437c11d9 --- /dev/null +++ b/Documentation/ABI/stable/sysfs-driver-w1_ds2438 @@ -0,0 +1,6 @@ +What: /sys/bus/w1/devices/.../page1 +Date: April 2021 +Contact: Luiz Sampaio +Description: read the contents of the page1 of the DS2438 + see Documentation/w1/slaves/w1_ds2438.rst for detailed information +Users: any user space application which wants to communicate with DS2438 diff --git a/Documentation/w1/slaves/w1_ds2438.rst b/Documentation/w1/slaves/w1_ds2438.rst index a29309a3f8e5..ac8d0d4b0d0e 100644 --- a/Documentation/w1/slaves/w1_ds2438.rst +++ b/Documentation/w1/slaves/w1_ds2438.rst @@ -44,6 +44,14 @@ Internally when this file is read, the additional CRC byte is also obtained from the slave device. If it is correct, the 8 bytes page data are passed to userspace, otherwise an I/O error is returned. +"page1" +------- +This file provides full 8 bytes of the chip Page 1 (01h). +This page contains the ICA, elapsed time meter and current offset data of the DS2438. +Internally when this file is read, the additional CRC byte is also obtained +from the slave device. If it is correct, the 8 bytes page data are passed +to userspace, otherwise an I/O error is returned. + "temperature" ------------- Opening and reading this file initiates the CONVERT_T (temperature conversion) diff --git a/drivers/w1/slaves/w1_ds2438.c b/drivers/w1/slaves/w1_ds2438.c index 1e95f3a256c7..42080ae779f0 100644 --- a/drivers/w1/slaves/w1_ds2438.c +++ b/drivers/w1/slaves/w1_ds2438.c @@ -49,6 +49,15 @@ #define DS2438_CURRENT_MSB 0x06 #define DS2438_THRESHOLD 0x07 +/* Page #1 definitions */ +#define DS2438_ETM_0 0x00 +#define DS2438_ETM_1 0x01 +#define DS2438_ETM_2 0x02 +#define DS2438_ETM_3 0x03 +#define DS2438_ICA 0x04 +#define DS2438_OFFSET_LSB 0x05 +#define DS2438_OFFSET_MSB 0x06 + static int w1_ds2438_get_page(struct w1_slave *sl, int pageno, u8 *buf) { unsigned int retries = W1_DS2438_RETRIES; @@ -325,6 +334,36 @@ static ssize_t page0_read(struct file *filp, struct kobject *kobj, return ret; } +static ssize_t page1_read(struct file *filp, struct kobject *kobj, + struct bin_attribute *bin_attr, char *buf, + loff_t off, size_t count) +{ + struct w1_slave *sl = kobj_to_w1_slave(kobj); + int ret; + u8 w1_buf[DS2438_PAGE_SIZE + 1 /*for CRC*/]; + + if (off != 0) + return 0; + if (!buf) + return -EINVAL; + + mutex_lock(&sl->master->bus_mutex); + + /* Read no more than page1 size */ + if (count > DS2438_PAGE_SIZE) + count = DS2438_PAGE_SIZE; + + if (w1_ds2438_get_page(sl, 1, w1_buf) == 0) { + memcpy(buf, &w1_buf, count); + ret = count; + } else + ret = -EIO; + + mutex_unlock(&sl->master->bus_mutex); + + return ret; +} + static ssize_t temperature_read(struct file *filp, struct kobject *kobj, struct bin_attribute *bin_attr, char *buf, loff_t off, size_t count) @@ -390,6 +429,7 @@ static ssize_t vdd_read(struct file *filp, struct kobject *kobj, static BIN_ATTR_RW(iad, 0); static BIN_ATTR_RO(page0, DS2438_PAGE_SIZE); +static BIN_ATTR_RO(page1, DS2438_PAGE_SIZE); static BIN_ATTR_RO(temperature, 0/* real length varies */); static BIN_ATTR_RO(vad, 0/* real length varies */); static BIN_ATTR_RO(vdd, 0/* real length varies */); @@ -397,6 +437,7 @@ static BIN_ATTR_RO(vdd, 0/* real length varies */); static struct bin_attribute *w1_ds2438_bin_attrs[] = { &bin_attr_iad, &bin_attr_page0, + &bin_attr_page1, &bin_attr_temperature, &bin_attr_vad, &bin_attr_vdd, -- 2.30.1