From patchwork Sat Mar 5 15:34:56 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Adam Baker X-Patchwork-Id: 8510581 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork2.web.kernel.org (Postfix) with ESMTP id 9529EC0553 for ; Sat, 5 Mar 2016 15:37:15 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 4B1CD2017D for ; Sat, 5 Mar 2016 15:37:14 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.9]) (using TLSv1.2 with cipher AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id E8E1F20173 for ; Sat, 5 Mar 2016 15:37:12 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1acEF3-0007w0-Og; Sat, 05 Mar 2016 15:35:41 +0000 Received: from avasout06.plus.net ([212.159.14.18]) by bombadil.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1acEEq-0007WX-MI for linux-arm-kernel@lists.infradead.org; Sat, 05 Mar 2016 15:35:30 +0000 Received: from debian.baker-net.org.uk ([212.159.113.184]) by avasout06 with smtp id SFb11s0053ymAd801Fb2Cl; Sat, 05 Mar 2016 15:35:06 +0000 X-CM-Score: 0.00 X-CNFS-Analysis: v=2.1 cv=Rr04V3SK c=1 sm=1 tr=0 a=fkd5KTHJFGKPA0tsLFcInQ==:117 a=fkd5KTHJFGKPA0tsLFcInQ==:17 a=L9H7d07YOLsA:10 a=9cW_t1CCXrUA:10 a=s5jvgZ67dGcA:10 a=7OsogOcEt9IA:10 a=gJibsqi4AAAA:8 a=aNednkirAAAA:8 a=2cJhgLHkKmX14XI90CYA:9 a=a1CADXucfts6VVlE:21 a=mBHXIlZ1V9hSlhf1:21 Received: from wendolene.baker-net.org.uk (wendolene.baker-net.org.uk [192.168.0.6]) by debian.baker-net.org.uk (Postfix) with ESMTP id 214D4CD41AA; Sat, 5 Mar 2016 15:35:01 +0000 (GMT) Received: by wendolene.baker-net.org.uk (Postfix, from userid 1000) id CDB4214F2034; Sat, 5 Mar 2016 15:35:00 +0000 (GMT) From: Adam Baker To: Jason Cooper , Andrew Lunn , Gregory Clement , Sebastian Hesselbarth , Jean Delvare , Guenter Roeck Subject: [PATCH v4 2/3] hwmon: Create an NSA320 hardware monitoring driver Date: Sat, 5 Mar 2016 15:34:56 +0000 Message-Id: <1457192097-32538-3-git-send-email-linux@baker-net.org.uk> X-Mailer: git-send-email 2.1.4 In-Reply-To: <1457192097-32538-1-git-send-email-linux@baker-net.org.uk> References: <1457192097-32538-1-git-send-email-linux@baker-net.org.uk> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20160305_073529_090243_E71D5E0D X-CRM114-Status: GOOD ( 29.80 ) X-Spam-Score: -2.6 (--) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Mark Rutland , devicetree@vger.kernel.org, Russell King , Pawel Moll , Ian Campbell , Adam Baker , lm-sensors@lm-sensors.org, Rob Herring , carl.wolfgang@googlemail.com, Kumar Gala , linux-arm-kernel@lists.infradead.org MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Spam-Status: No, score=-4.2 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_MED, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Create a driver to support the hardware monitoring chip present in the Zyxel NSA320 and some of the other Zyxel NAS devices. The driver reads fan speed and temperature from a suitably pre-programmed MCU on the device. Signed-off-by: Adam Baker --- Changes since v3 - change return type of nsa320_hwmon_update to s32 - eliminate use of IS_ERR_VALUE() - fix some remaining refernces to NSA3XX rather than NSA320 Changes since v2 Updated based on Guenter Roeck's review, - return a single value that is result or error from the update function - use separate show_value routimes for fan and temp - Added Documentation/hwmon/nsa320-hwmon --- Documentation/hwmon/nsa320 | 53 +++++++++++ drivers/hwmon/Kconfig | 15 +++ drivers/hwmon/Makefile | 1 + drivers/hwmon/nsa320-hwmon.c | 216 +++++++++++++++++++++++++++++++++++++++++++ 4 files changed, 285 insertions(+) create mode 100644 Documentation/hwmon/nsa320 create mode 100644 drivers/hwmon/nsa320-hwmon.c diff --git a/Documentation/hwmon/nsa320 b/Documentation/hwmon/nsa320 new file mode 100644 index 0000000..fdbd694 --- /dev/null +++ b/Documentation/hwmon/nsa320 @@ -0,0 +1,53 @@ +Kernel driver nsa320_hwmon +========================== + +Supported chips: + * Holtek HT46R065 microcontroller with onboard firmware that configures + it to act as a hardware monitor. + Prefix: 'nsa320' + Addresses scanned: none + Datasheet: Not available, driver was reverse engineered based upon the + Zyxel kernel source + +Author: + Adam Baker + +Description +----------- + +This chip is known to be used in the Zyxel NSA320 and NSA325 NAS Units and +also in some variants of the NSA310 but the driver has only been tested +on the NSA320. In all of these devices it is connected to the same 3 GPIO +lines which are used to provide chip select, clock and data lines. The +interface behaves similarly to SPI but at much lower speeds than are normally +used for SPI. + +Following each chip select pulse the chip will generate a single 32 bit word +that contains 0x55 as a marker to indicate that data is being read correctly, +followed by an 8 bit fan speed in 100s of RPM and a 16 bit temperature in +tenths of a degree. + + +sysfs-Interface +--------------- + +temp1_input - temperature input +fan1_input - fan speed + +Notes +----- + +The access timings used in the driver are the same as used in the Zyxel +provided kernel. Testing has shown that if the delay between chip select and +the first clock pulse is reduced from 100 ms to just under 10ms then the chip +will not produce any output. If the duration of either phase of the clock +is reduced from 100 us to less than 15 us then data pulses are likely to be +read twice corrupting the output. The above analysis is based upon a sample +of one unit but suggests that the Zyxel provided delay values include a +reasonable tolerance. + +The driver incorporates a limit that it will not check for updated values +faster than once a second. This is because the hardware takes a relatively long +time to read the data from the device and when it does it reads both temp and +fan speed. As the most likely case for two accesses in quick succession is +to read both of these values avoiding a second read delay is desirable. diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig index 80a73bf..08fd7f5 100644 --- a/drivers/hwmon/Kconfig +++ b/drivers/hwmon/Kconfig @@ -1186,6 +1186,21 @@ config SENSORS_NCT7904 This driver can also be built as a module. If so, the module will be called nct7904. +config SENSORS_NSA320 + tristate "ZyXEL NSA320 and compatible fan speed and temperature sensors" + depends on GPIOLIB && OF + depends on MACH_KIRKWOOD || COMPILE_TEST + help + If you say yes here you get support for hardware monitoring + for the ZyXEL NSA320 Media Server and other compatible devices + (probably the NSA325 and some NSA310 variants). + + The sensor data is taken from a Holtek HT46R065 microcontroller + connected to GPIO lines. + + This driver can also be built as a module. If so, the module + will be called nsa320-hwmon. + config SENSORS_PCF8591 tristate "Philips PCF8591 ADC/DAC" depends on I2C diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile index 12a3239..9e22cf7 100644 --- a/drivers/hwmon/Makefile +++ b/drivers/hwmon/Makefile @@ -124,6 +124,7 @@ obj-$(CONFIG_SENSORS_NCT6683) += nct6683.o obj-$(CONFIG_SENSORS_NCT6775) += nct6775.o obj-$(CONFIG_SENSORS_NCT7802) += nct7802.o obj-$(CONFIG_SENSORS_NCT7904) += nct7904.o +obj-$(CONFIG_SENSORS_NSA320) += nsa320-hwmon.o obj-$(CONFIG_SENSORS_NTC_THERMISTOR) += ntc_thermistor.o obj-$(CONFIG_SENSORS_PC87360) += pc87360.o obj-$(CONFIG_SENSORS_PC87427) += pc87427.o diff --git a/drivers/hwmon/nsa320-hwmon.c b/drivers/hwmon/nsa320-hwmon.c new file mode 100644 index 0000000..456a9f2 --- /dev/null +++ b/drivers/hwmon/nsa320-hwmon.c @@ -0,0 +1,216 @@ +/* + * drivers/hwmon/nsa320-hwmon.c + * + * ZyXEL NSA320 Media Servers + * hardware monitoring + * + * Copyright (C) 2016 Adam Baker + * based on a board file driver + * Copyright (C) 2012 Peter Schildmann + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License v2 as published by the + * Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for + * more details. + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +/* Tests for error return values rely upon this value being < 0x80 */ +#define MAGIC_NUMBER 0x55 + +/* + * The Zyxel hwmon MCU is a Holtek HT46R065 that is factory programmed + * to perform temperature and fan speed monitoring. It is read by taking + * the active pin low. The 32 bit output word is then clocked onto the + * data line. The MSB of the data word is a magic nuber to indicate it + * has been read correctly, the next byte is the fan speed (in hundreds + * of RPM) and the last two bytes are the temperature (in tenths of a + * degree) + */ + +struct nsa320_hwmon { + struct mutex update_lock; /* lock GPIO operations */ + unsigned long last_updated; /* jiffies */ + unsigned long mcu_data; + struct gpio_desc *act; + struct gpio_desc *clk; + struct gpio_desc *data; +}; + +enum nsa320_inputs { + NSA320_TEMP = 0, + NSA320_FAN = 1, +}; + +static const char * const nsa320_input_names[] = { + [NSA320_TEMP] = "System Temperature", + [NSA320_FAN] = "Chassis Fan", +}; + +/* + * Although this protocol looks similar to SPI the long delay + * between the active (aka chip select) signal and the shorter + * delay between clock pulses are needed for reliable operation. + * The delays provided are taken from the manufacturer kernel, + * testing suggest they probably incorporate a reasonable safety + * margin. (The single device tested became unreliable if the + * delay was reduced to 1/10th of this value.) + */ +static s32 nsa320_hwmon_update(struct device *dev) +{ + u32 mcu_data; + u32 mask; + struct nsa320_hwmon *hwmon = dev_get_drvdata(dev); + + mutex_lock(&hwmon->update_lock); + + mcu_data = hwmon->mcu_data; + + if (time_after(jiffies, hwmon->last_updated + HZ) || mcu_data == 0) { + gpiod_set_value(hwmon->act, 1); + msleep(100); + + mcu_data = 0; + for (mask = BIT(31); mask; mask >>= 1) { + gpiod_set_value(hwmon->clk, 0); + usleep_range(100, 200); + gpiod_set_value(hwmon->clk, 1); + usleep_range(100, 200); + if (gpiod_get_value(hwmon->data)) + mcu_data |= mask; + } + + gpiod_set_value(hwmon->act, 0); + dev_dbg(dev, "Read raw MCU data %08x\n", mcu_data); + + if ((mcu_data >> 24) != MAGIC_NUMBER) { + dev_dbg(dev, "Read invalid MCU data %08x\n", mcu_data); + mcu_data = -EIO; + } else { + hwmon->mcu_data = mcu_data; + hwmon->last_updated = jiffies; + } + } + + mutex_unlock(&hwmon->update_lock); + + return mcu_data; +} + +static ssize_t show_label(struct device *dev, + struct device_attribute *attr, char *buf) +{ + int channel = to_sensor_dev_attr(attr)->index; + + return sprintf(buf, "%s\n", nsa320_input_names[channel]); +} + +static ssize_t show_temp(struct device *dev, struct device_attribute *attr, + char *buf) +{ + s32 mcu_data = nsa320_hwmon_update(dev); + + if (mcu_data < 0) + return mcu_data; + + return sprintf(buf, "%d\n", (mcu_data & 0xffff) * 100); +} + +static ssize_t show_fan(struct device *dev, struct device_attribute *attr, + char *buf) +{ + s32 mcu_data = nsa320_hwmon_update(dev); + + if (mcu_data < 0) + return mcu_data; + + return sprintf(buf, "%d\n", ((mcu_data & 0xff0000) >> 16) * 100); +} + +static SENSOR_DEVICE_ATTR(temp1_label, S_IRUGO, show_label, NULL, NSA320_TEMP); +static DEVICE_ATTR(temp1_input, S_IRUGO, show_temp, NULL); +static SENSOR_DEVICE_ATTR(fan1_label, S_IRUGO, show_label, NULL, NSA320_FAN); +static DEVICE_ATTR(fan1_input, S_IRUGO, show_fan, NULL); + +static struct attribute *nsa320_attrs[] = { + &sensor_dev_attr_temp1_label.dev_attr.attr, + &dev_attr_temp1_input.attr, + &sensor_dev_attr_fan1_label.dev_attr.attr, + &dev_attr_fan1_input.attr, + NULL +}; + +ATTRIBUTE_GROUPS(nsa320); + +static const struct of_device_id of_nsa320_hwmon_match[] = { + { .compatible = "zyxel,nsa320-mcu", }, + { }, +}; + +static int nsa320_hwmon_probe(struct platform_device *pdev) +{ + struct nsa320_hwmon *hwmon; + struct device *classdev; + + hwmon = devm_kzalloc(&pdev->dev, sizeof(*hwmon), GFP_KERNEL); + if (!hwmon) + return -ENOMEM; + + /* Look up the GPIO pins to use */ + hwmon->act = devm_gpiod_get(&pdev->dev, "act", GPIOD_OUT_LOW); + if (IS_ERR(hwmon->act)) + return PTR_ERR(hwmon->act); + + hwmon->clk = devm_gpiod_get(&pdev->dev, "clk", GPIOD_OUT_HIGH); + if (IS_ERR(hwmon->clk)) + return PTR_ERR(hwmon->clk); + + hwmon->data = devm_gpiod_get(&pdev->dev, "data", GPIOD_IN); + if (IS_ERR(hwmon->data)) + return PTR_ERR(hwmon->data); + + mutex_init(&hwmon->update_lock); + + classdev = devm_hwmon_device_register_with_groups(&pdev->dev, + "nsa320", hwmon, nsa320_groups); + + return PTR_ERR_OR_ZERO(classdev); + +} + +/* All allocations use devres so remove() is not needed. */ + +static struct platform_driver nsa320_hwmon_driver = { + .probe = nsa320_hwmon_probe, + .driver = { + .name = "nsa320-hwmon", + .owner = THIS_MODULE, + .of_match_table = of_match_ptr(of_nsa320_hwmon_match), + }, +}; + +module_platform_driver(nsa320_hwmon_driver); + +MODULE_DEVICE_TABLE(of, of_nsa320_hwmon_match); +MODULE_AUTHOR("Peter Schildmann "); +MODULE_AUTHOR("Adam Baker "); +MODULE_DESCRIPTION("NSA320 Hardware Monitoring"); +MODULE_LICENSE("GPL v2"); +MODULE_ALIAS("platform:nsa320-hwmon");