From patchwork Tue Nov 17 01:09:43 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Tao Ren X-Patchwork-Id: 11911109 X-Patchwork-Delegate: kuba@kernel.org 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=-12.6 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, 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 93CBEC63777 for ; Tue, 17 Nov 2020 01:10:18 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5A9AA24694 for ; Tue, 17 Nov 2020 01:10:18 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="QsmgCf+C" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731576AbgKQBJ6 (ORCPT ); Mon, 16 Nov 2020 20:09:58 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59900 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728779AbgKQBJ5 (ORCPT ); Mon, 16 Nov 2020 20:09:57 -0500 Received: from mail-pg1-x543.google.com (mail-pg1-x543.google.com [IPv6:2607:f8b0:4864:20::543]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1FB33C0613CF; Mon, 16 Nov 2020 17:09:57 -0800 (PST) Received: by mail-pg1-x543.google.com with SMTP id e21so14810736pgr.11; Mon, 16 Nov 2020 17:09:57 -0800 (PST) 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; bh=e/IegTC1nzz3ON1xySPtjDRJgwT23h4pdg52sOpqi/E=; b=QsmgCf+C4J16pGh4GVPXMB5KWc+eiDU/VoNlfPiIm5CGBCDYSdxESDXHb1SvTZ7XlR 16KHDJh71/Wy2h6O0hL+3w7NL/pmNnoBK62FIbtHnegMzzur0LSc3kSV2cE/cE65qzms RQ1hn3rxcdIIoblc2rySdxPpi7NUhnl/zqMJmSwzPIGB047PGo0L7sK92IhRIrDwxU+I Gmg96LLTFZLkuVoFS1HgzXg3LUZu6onEncNGnFZiNkVZGAO+78Da8IFn6pQiNzoIlgrn ksVqueIXNgQ1ZOluALHNY5n735xBq7jb8YDHUiO9gW+ezVzwD8X0osg8M+rZO0U43WM5 17TA== 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; bh=e/IegTC1nzz3ON1xySPtjDRJgwT23h4pdg52sOpqi/E=; b=sQRYEC1zpSOf7Ca4XpKcCJg4k8JV8rP0CXZRxo0yhNPEgvT0zPj3Smqe/xVXriTSOn 2qMifbE4R6kZM+bE2QYNxu1v4K6YKCMlrlW9pqVuQZVEzmE4xtXtaaN2mGfH7TbKF5n/ Co9QFzJBxFF2JXbVJBbMs4/hrTPJPaITa34fkxMzt5JKiqn3tVSGSZHOijwwe7QWIS7J Y9HJEs9wBocGoTBtzgLZlbdBknzOt5vXu7/kzUdDJegjnZd2b7XH0yLu/Q5GkUzN94VK imsAdQyL3h6RV1Xe740/+apmXA2NEBiVBKngTU3xt7WKXcf40DJeqEh1PaUI4pbbIcnP tilg== X-Gm-Message-State: AOAM532K6hi/pI+9piG9oPmcweBT1TPLStB9RUoMpwepioNhssYrtmCC 13mjisCGxB/842McIYbgLBk= X-Google-Smtp-Source: ABdhPJwh+NYZnw/7oS4tjiV0DxVXKfIRhqstbwjasDhD41C2oIwGuEzBfF35TYbB1FVQZGJCOnvuUg== X-Received: by 2002:a65:6219:: with SMTP id d25mr1475293pgv.1.1605575396591; Mon, 16 Nov 2020 17:09:56 -0800 (PST) Received: from taoren-ubuntu-R90MNF91.thefacebook.com (c-73-252-146-110.hsd1.ca.comcast.net. [73.252.146.110]) by smtp.gmail.com with ESMTPSA id m23sm7362091pfo.136.2020.11.16.17.09.54 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 16 Nov 2020 17:09:56 -0800 (PST) From: rentao.bupt@gmail.com To: Jean Delvare , Guenter Roeck , Jonathan Corbet , Alexei Starovoitov , Daniel Borkmann , "David S . Miller" , Jakub Kicinski , Jesper Dangaard Brouer , John Fastabend , linux-hwmon@vger.kernel.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, bpf@vger.kernel.org, openbmc@lists.ozlabs.org, taoren@fb.com, mikechoi@fb.com Cc: Tao Ren Subject: [PATCH 1/2] hwmon: (max127) Add Maxim MAX127 hardware monitoring driver Date: Mon, 16 Nov 2020 17:09:43 -0800 Message-Id: <20201117010944.28457-2-rentao.bupt@gmail.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20201117010944.28457-1-rentao.bupt@gmail.com> References: <20201117010944.28457-1-rentao.bupt@gmail.com> Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org From: Tao Ren Add hardware monitoring driver for the Maxim MAX127 chip. MAX127 min/max range handling code is inspired by the max197 driver. Signed-off-by: Tao Ren --- drivers/hwmon/Kconfig | 9 ++ drivers/hwmon/Makefile | 1 + drivers/hwmon/max127.c | 286 +++++++++++++++++++++++++++++++++++++++++ 3 files changed, 296 insertions(+) create mode 100644 drivers/hwmon/max127.c diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig index 9d600e0c5584..716df51edc87 100644 --- a/drivers/hwmon/Kconfig +++ b/drivers/hwmon/Kconfig @@ -950,6 +950,15 @@ config SENSORS_MAX1111 This driver can also be built as a module. If so, the module will be called max1111. +config SENSORS_MAX127 + tristate "Maxim MAX127 12-bit 8-channel Data Acquisition System" + depends on I2C + help + Say y here to support Maxim's MAX127 DAS chips. + + This driver can also be built as a module. If so, the module + will be called max127. + config SENSORS_MAX16065 tristate "Maxim MAX16065 System Manager and compatibles" depends on I2C diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile index 1083bbfac779..01ca5d3fbad4 100644 --- a/drivers/hwmon/Makefile +++ b/drivers/hwmon/Makefile @@ -127,6 +127,7 @@ obj-$(CONFIG_SENSORS_LTC4260) += ltc4260.o obj-$(CONFIG_SENSORS_LTC4261) += ltc4261.o obj-$(CONFIG_SENSORS_LTQ_CPUTEMP) += ltq-cputemp.o obj-$(CONFIG_SENSORS_MAX1111) += max1111.o +obj-$(CONFIG_SENSORS_MAX127) += max127.o obj-$(CONFIG_SENSORS_MAX16065) += max16065.o obj-$(CONFIG_SENSORS_MAX1619) += max1619.o obj-$(CONFIG_SENSORS_MAX1668) += max1668.o diff --git a/drivers/hwmon/max127.c b/drivers/hwmon/max127.c new file mode 100644 index 000000000000..df74a95bcf28 --- /dev/null +++ b/drivers/hwmon/max127.c @@ -0,0 +1,286 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Hardware monitoring driver for MAX127. + * + * Copyright (c) 2020 Facebook Inc. + */ + +#include +#include +#include +#include +#include +#include +#include + +/* MAX127 Control Byte. */ +#define MAX127_CTRL_START BIT(7) +#define MAX127_CTRL_SEL_OFFSET 4 +#define MAX127_CTRL_RNG BIT(3) +#define MAX127_CTRL_BIP BIT(2) +#define MAX127_CTRL_PD1 BIT(1) +#define MAX127_CTRL_PD0 BIT(0) + +#define MAX127_NUM_CHANNELS 8 +#define MAX127_SET_CHANNEL(ch) (((ch) & 7) << (MAX127_CTRL_SEL_OFFSET)) + +#define MAX127_INPUT_LIMIT 10 /* 10V */ + +/* + * MAX127 returns 2 bytes at read: + * - the first byte contains data[11:4]. + * - the second byte contains data[3:0] (MSB) and 4 dummy 0s (LSB). + */ +#define MAX127_DATA1_SHIFT 4 + +struct max127_data { + struct mutex lock; + struct i2c_client *client; + int input_limit; + u8 ctrl_byte[MAX127_NUM_CHANNELS]; +}; + +static int max127_select_channel(struct max127_data *data, int channel) +{ + int status; + struct i2c_client *client = data->client; + struct i2c_msg msg = { + .addr = client->addr, + .flags = 0, + .len = 1, + .buf = &data->ctrl_byte[channel], + }; + + status = i2c_transfer(client->adapter, &msg, 1); + if (status != 1) + return status; + + return 0; +} + +static int max127_read_channel(struct max127_data *data, int channel, u16 *vin) +{ + int status; + u8 i2c_data[2]; + struct i2c_client *client = data->client; + struct i2c_msg msg = { + .addr = client->addr, + .flags = I2C_M_RD, + .len = 2, + .buf = i2c_data, + }; + + status = i2c_transfer(client->adapter, &msg, 1); + if (status != 1) + return status; + + *vin = ((i2c_data[0] << 8) | i2c_data[1]) >> MAX127_DATA1_SHIFT; + return 0; +} + +static ssize_t max127_input_show(struct device *dev, + struct device_attribute *dev_attr, + char *buf) +{ + u16 vin; + int status; + struct max127_data *data = dev_get_drvdata(dev); + struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr); + + if (mutex_lock_interruptible(&data->lock)) + return -ERESTARTSYS; + + status = max127_select_channel(data, attr->index); + if (status) + goto exit; + + status = max127_read_channel(data, attr->index, &vin); + if (status) + goto exit; + + status = sprintf(buf, "%u", vin); + +exit: + mutex_unlock(&data->lock); + return status; +} + +static ssize_t max127_range_show(struct device *dev, + struct device_attribute *dev_attr, + char *buf) +{ + u8 ctrl, rng_bip; + struct max127_data *data = dev_get_drvdata(dev); + struct sensor_device_attribute_2 *attr = to_sensor_dev_attr_2(dev_attr); + int rng_type = attr->nr; /* 0 for min, 1 for max */ + int channel = attr->index; + int full = data->input_limit; + int half = full / 2; + int range_table[4][2] = { + [0] = {0, half}, /* RNG=0, BIP=0 */ + [1] = {-half, half}, /* RNG=0, BIP=1 */ + [2] = {0, full}, /* RNG=1, BIP=0 */ + [3] = {-full, full}, /* RNG=1, BIP=1 */ + }; + + if (mutex_lock_interruptible(&data->lock)) + return -ERESTARTSYS; + ctrl = data->ctrl_byte[channel]; + mutex_unlock(&data->lock); + + rng_bip = (ctrl >> 2) & 3; + return sprintf(buf, "%d", range_table[rng_bip][rng_type]); +} + +static void max127_set_range(struct max127_data *data, int channel) +{ + data->ctrl_byte[channel] |= MAX127_CTRL_RNG; +} + +static void max127_clear_range(struct max127_data *data, int channel) +{ + data->ctrl_byte[channel] &= ~MAX127_CTRL_RNG; +} + +static void max127_set_polarity(struct max127_data *data, int channel) +{ + data->ctrl_byte[channel] |= MAX127_CTRL_BIP; +} + +static void max127_clear_polarity(struct max127_data *data, int channel) +{ + data->ctrl_byte[channel] &= ~MAX127_CTRL_BIP; +} + +static ssize_t max127_range_store(struct device *dev, + struct device_attribute *devattr, + const char *buf, + size_t count) +{ + struct max127_data *data = dev_get_drvdata(dev); + struct sensor_device_attribute_2 *attr = to_sensor_dev_attr_2(devattr); + int rng_type = attr->nr; /* 0 for min, 1 for max */ + int channel = attr->index; + int full = data->input_limit; + int half = full / 2; + long input, output; + + if (kstrtol(buf, 0, &input)) + return -EINVAL; + + if (rng_type == 0) { /* min input */ + if (input <= -full) + output = -full; + else if (input < 0) + output = -half; + else + output = 0; + } else { /* max input */ + output = (input >= full) ? full : half; + } + + if (mutex_lock_interruptible(&data->lock)) + return -ERESTARTSYS; + + if (output == -full) { + max127_set_polarity(data, channel); + max127_set_range(data, channel); + } else if (output == -half) { + max127_set_polarity(data, channel); + max127_clear_range(data, channel); + } else if (output == 0) { + max127_clear_polarity(data, channel); + } else if (output == half) { + max127_clear_range(data, channel); + } else { + max127_set_range(data, channel); + } + + mutex_unlock(&data->lock); + + return count; +} + +#define MAX127_SENSOR_DEV_ATTR_DEF(ch) \ + static SENSOR_DEVICE_ATTR_RO(in##ch##_input, max127_input, ch); \ + static SENSOR_DEVICE_ATTR_2_RW(in##ch##_min, max127_range, 0, ch); \ + static SENSOR_DEVICE_ATTR_2_RW(in##ch##_max, max127_range, 1, ch) + +MAX127_SENSOR_DEV_ATTR_DEF(0); +MAX127_SENSOR_DEV_ATTR_DEF(1); +MAX127_SENSOR_DEV_ATTR_DEF(2); +MAX127_SENSOR_DEV_ATTR_DEF(3); +MAX127_SENSOR_DEV_ATTR_DEF(4); +MAX127_SENSOR_DEV_ATTR_DEF(5); +MAX127_SENSOR_DEV_ATTR_DEF(6); +MAX127_SENSOR_DEV_ATTR_DEF(7); + +#define MAX127_SENSOR_DEVICE_ATTR(ch) \ + &sensor_dev_attr_in##ch##_input.dev_attr.attr, \ + &sensor_dev_attr_in##ch##_min.dev_attr.attr, \ + &sensor_dev_attr_in##ch##_max.dev_attr.attr + +static struct attribute *max127_attrs[] = { + MAX127_SENSOR_DEVICE_ATTR(0), + MAX127_SENSOR_DEVICE_ATTR(1), + MAX127_SENSOR_DEVICE_ATTR(2), + MAX127_SENSOR_DEVICE_ATTR(3), + MAX127_SENSOR_DEVICE_ATTR(4), + MAX127_SENSOR_DEVICE_ATTR(5), + MAX127_SENSOR_DEVICE_ATTR(6), + MAX127_SENSOR_DEVICE_ATTR(7), + NULL, +}; + +ATTRIBUTE_GROUPS(max127); + +static const struct attribute_group max127_attr_groups = { + .attrs = max127_attrs, +}; + +static int max127_probe(struct i2c_client *client, + const struct i2c_device_id *id) +{ + int i; + struct device *hwmon_dev; + struct max127_data *data; + struct device *dev = &client->dev; + + data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL); + if (!data) + return -ENOMEM; + + data->client = client; + mutex_init(&data->lock); + data->input_limit = MAX127_INPUT_LIMIT; + for (i = 0; i < ARRAY_SIZE(data->ctrl_byte); i++) + data->ctrl_byte[i] = (MAX127_CTRL_START | + MAX127_SET_CHANNEL(i)); + + hwmon_dev = devm_hwmon_device_register_with_groups(dev, + client->name, data, max127_groups); + + return PTR_ERR_OR_ZERO(hwmon_dev); +} + +static const struct i2c_device_id max127_id[] = { + { "max127", 0 }, + { } +}; +MODULE_DEVICE_TABLE(i2c, max127_id); + +static struct i2c_driver max127_driver = { + .class = I2C_CLASS_HWMON, + .driver = { + .name = "max127", + }, + .probe = max127_probe, + .id_table = max127_id, +}; + +module_i2c_driver(max127_driver); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Mike Choi "); +MODULE_AUTHOR("Tao Ren "); +MODULE_DESCRIPTION("MAX127 Hardware Monitoring driver");