Create a driver to support the hardware monitoring chip present in several models of Zyxel NSA3xx NAS devices. The driver reads fan speed and temperature from a suitably programmed MCU on the device. Signed-off-by: Adam Baker <linux@xxxxxxxxxxxxxxxx> --- I've tested this on an NSA-320, I've had someone offer to test it on NSA-325 so hopefully I will get a tested by back. --- drivers/hwmon/Kconfig | 13 +++ drivers/hwmon/Makefile | 1 + drivers/hwmon/nsa3xx-hwmon.c | 223 +++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 237 insertions(+) create mode 100644 drivers/hwmon/nsa3xx-hwmon.c diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig index 80a73bf..8801b78 100644 --- a/drivers/hwmon/Kconfig +++ b/drivers/hwmon/Kconfig @@ -1757,6 +1757,19 @@ config SENSORS_ULTRA45 This driver provides support for the Ultra45 workstation environmental sensors. +config SENSORS_NSA3XX + tristate "ZyXEL NSA3xx fan speed and temperature sensors" + depends on GPIOLIB && OF + help + If you say yes here you get support for hardware monitoring + for the ZyXEL NSA3XX Media Servers. + + 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 nsa3xx-hwmon. + if ACPI comment "ACPI drivers" diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile index 12a3239..e85414a 100644 --- a/drivers/hwmon/Makefile +++ b/drivers/hwmon/Makefile @@ -118,6 +118,7 @@ obj-$(CONFIG_SENSORS_MAX6650) += max6650.o obj-$(CONFIG_SENSORS_MAX6697) += max6697.o obj-$(CONFIG_SENSORS_MAX31790) += max31790.o obj-$(CONFIG_SENSORS_MC13783_ADC)+= mc13783-adc.o +obj-$(CONFIG_SENSORS_NSA3XX) += nsa3xx-hwmon.o obj-$(CONFIG_SENSORS_MCP3021) += mcp3021.o obj-$(CONFIG_SENSORS_MENF21BMC_HWMON) += menf21bmc_hwmon.o obj-$(CONFIG_SENSORS_NCT6683) += nct6683.o diff --git a/drivers/hwmon/nsa3xx-hwmon.c b/drivers/hwmon/nsa3xx-hwmon.c new file mode 100644 index 0000000..0fbf118 --- /dev/null +++ b/drivers/hwmon/nsa3xx-hwmon.c @@ -0,0 +1,223 @@ +/* + * drivers/hwmon/nsa3xx-hwmon.c + * + * ZyXEL NSA3xx Media Servers + * hardware monitoring + * + * Copyright (C) 2016 Adam Baker <linux@xxxxxxxxxxxxxxxx> + * based on a board file driver + * Copyright (C) 2012 Peter Schildmann <linux@xxxxxxxxxxxxxxx> + * + * 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 <linux/module.h> +#include <linux/mutex.h> +#include <linux/platform_device.h> +#include <linux/err.h> +#include <linux/gpio/consumer.h> +#include <linux/hwmon.h> +#include <linux/hwmon-sysfs.h> +#include <linux/jiffies.h> +#include <linux/delay.h> +#include <linux/of.h> +#include <linux/of_device.h> +#include <linux/of_platform.h> + +#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 nsa3xx_hwmon { + struct device *classdev; + struct mutex update_lock; /* lock GPIO operations */ + unsigned long last_updated; /* jiffies */ + u32 mcu_data; + struct gpio_desc *act; + struct gpio_desc *clk; + struct gpio_desc *data; +}; + +enum nsa3xx_inputs { + NSA3XX_FAN = 1, + NSA3XX_TEMP = 0, +}; + +static const char * const nsa3xx_input_names[] = { + [NSA3XX_FAN] = "Chassis Fan", + [NSA3XX_TEMP] = "System Temperature", +}; + +/* 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 unsigned long nsa3xx_hwmon_update(struct device *dev) +{ + u32 mcu_data; + u32 mask; + struct nsa3xx_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); + + 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_err(dev, "Read invalid MCU data %08x\n", mcu_data); + mcu_data = 0; + } + + 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", nsa3xx_input_names[channel]); +} + +static ssize_t show_value(struct device *dev, + struct device_attribute *attr, char *buf) +{ + int channel = to_sensor_dev_attr(attr)->index; + unsigned long mcu_data = nsa3xx_hwmon_update(dev); + unsigned long value = 0; + + pr_debug("channel value 0x%02x!\n", channel); + switch (channel) { + case NSA3XX_TEMP: + value = (mcu_data & 0xffff) * 100; + break; + case NSA3XX_FAN: + value = ((mcu_data & 0xff0000) >> 16) * 100; + break; + } + return sprintf(buf, "%lu\n", value); +} + +static SENSOR_DEVICE_ATTR(temp1_label, S_IRUGO, show_label, NULL, NSA3XX_TEMP); +static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_value, NULL, NSA3XX_TEMP); +static SENSOR_DEVICE_ATTR(fan1_label, S_IRUGO, show_label, NULL, NSA3XX_FAN); +static SENSOR_DEVICE_ATTR(fan1_input, S_IRUGO, show_value, NULL, NSA3XX_FAN); + +static struct attribute *nsa3xx_attrs[] = { + &sensor_dev_attr_temp1_label.dev_attr.attr, + &sensor_dev_attr_temp1_input.dev_attr.attr, + &sensor_dev_attr_fan1_label.dev_attr.attr, + &sensor_dev_attr_fan1_input.dev_attr.attr, + NULL +}; + +ATTRIBUTE_GROUPS(nsa3xx); + +static const struct of_device_id of_nsa3xx_hwmon_match[] = { + { .compatible = "zyxel,nsa320-mcu", }, + { }, +}; + +static int nsa3xx_hwmon_probe(struct platform_device *pdev) +{ + struct nsa3xx_hwmon *hwmon; + + hwmon = devm_kzalloc(&pdev->dev, sizeof(*hwmon), GFP_KERNEL); + if (!hwmon) + return -ENOMEM; + + platform_set_drvdata(pdev, hwmon); + + /* Look up the GPIO pins to use */ + hwmon->act = devm_gpiod_get(&pdev->dev, "act", GPIOD_OUT_LOW); + hwmon->clk = devm_gpiod_get(&pdev->dev, "clk", GPIOD_OUT_HIGH); + hwmon->data = devm_gpiod_get(&pdev->dev, "data", GPIOD_IN); + + if (IS_ERR(hwmon->act)) + return PTR_ERR(hwmon->act); + if (IS_ERR(hwmon->clk)) + return PTR_ERR(hwmon->clk); + if (IS_ERR(hwmon->data)) + return PTR_ERR(hwmon->data); + + mutex_init(&hwmon->update_lock); + + hwmon->classdev = devm_hwmon_device_register_with_groups(&pdev->dev, + "nsa3xx", hwmon, nsa3xx_groups); + if (IS_ERR(hwmon->classdev)) + return PTR_ERR(hwmon->classdev); + + dev_dbg(&pdev->dev, "initialized\n"); + + return 0; +} + +static int nsa3xx_hwmon_remove(struct platform_device *pdev) +{ + /* All resources are allocated with devm_*() so + * there is nothing to do here. + */ + + return 0; +} + +static struct platform_driver nsa3xx_hwmon_driver = { + .probe = nsa3xx_hwmon_probe, + .remove = nsa3xx_hwmon_remove, + .driver = { + .name = "nsa3xx-hwmon", + .owner = THIS_MODULE, + .of_match_table = of_match_ptr(of_nsa3xx_hwmon_match), + }, +}; + +module_platform_driver(nsa3xx_hwmon_driver); + +MODULE_DEVICE_TABLE(of, of_nsa3xx_hwmon_match); +MODULE_AUTHOR("Peter Schildmann <linux@xxxxxxxxxxxxxxx>"); +MODULE_AUTHOR("Adam Baker <linux@xxxxxxxxxxxxxxxx>"); +MODULE_DESCRIPTION("NSA3XX Hardware Monitoring"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("platform:nsa3xx-hwmon"); -- 2.1.4 -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html