[PATCH 2/2] hwmon: Add SFR NB6 sensor driver

From: Ãlvaro FernÃndez Rojas
Date: Sun Jun 07 2020 - 14:25:38 EST


SFR NeufBox 6 is equipped with an I2C connected chip to monitor voltage,
temperature and other stats. It also has a PWM LEDs that can be manually
controlled or set to specific hardware monitoring modes.

Signed-off-by: Ãlvaro FernÃndez Rojas <noltari@xxxxxxxxx>
---
drivers/hwmon/Kconfig | 11 +
drivers/hwmon/Makefile | 1 +
drivers/hwmon/nb6-hwmon.c | 466 ++++++++++++++++++++++++++++++++++++++
3 files changed, 478 insertions(+)
create mode 100644 drivers/hwmon/nb6-hwmon.c

diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
index 288ae9f63588..5523de75868d 100644
--- a/drivers/hwmon/Kconfig
+++ b/drivers/hwmon/Kconfig
@@ -1092,6 +1092,17 @@ config SENSORS_MENF21BMC_HWMON
This driver can also be built as a module. If so the module
will be called menf21bmc_hwmon.

+config SENSORS_NB6_HWMON
+ tristate "SFR NeufBox 6 (NB6) Hardware Monitoring"
+ depends on I2C
+ depends on PWM
+ help
+ If you say yes here you get support for SFR NeufBox 6 PWM LEDs,
+ temperature and voltage sensors.
+
+ This driver can also be built as a module. If so, the module
+ will be called nb6-hwmon.
+
config SENSORS_ADCXX
tristate "National Semiconductor ADCxxxSxxx"
depends on SPI_MASTER
diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile
index 3e32c21f5efe..5a35fde42bd8 100644
--- a/drivers/hwmon/Makefile
+++ b/drivers/hwmon/Makefile
@@ -141,6 +141,7 @@ obj-$(CONFIG_SENSORS_MCP3021) += mcp3021.o
obj-$(CONFIG_SENSORS_TC654) += tc654.o
obj-$(CONFIG_SENSORS_MLXREG_FAN) += mlxreg-fan.o
obj-$(CONFIG_SENSORS_MENF21BMC_HWMON) += menf21bmc_hwmon.o
+obj-$(CONFIG_SENSORS_NB6_HWMON) += nb6-hwmon.o
obj-$(CONFIG_SENSORS_NCT6683) += nct6683.o
obj-$(CONFIG_SENSORS_NCT6775) += nct6775.o
obj-$(CONFIG_SENSORS_NCT7802) += nct7802.o
diff --git a/drivers/hwmon/nb6-hwmon.c b/drivers/hwmon/nb6-hwmon.c
new file mode 100644
index 000000000000..aebb6ebbf3a8
--- /dev/null
+++ b/drivers/hwmon/nb6-hwmon.c
@@ -0,0 +1,466 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Driver for SFR NeufBox 6 Hardware Monitoring
+ *
+ * Copyright 2020 Ãlvaro FernÃndez Rojas <noltari@xxxxxxxxx>
+ */
+#include <linux/delay.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/i2c.h>
+#include <linux/hwmon.h>
+#include <linux/err.h>
+#include <linux/mutex.h>
+#include <linux/pwm.h>
+#include <linux/sysfs.h>
+
+#define NB6_LEDS_PWM_REG 0x10
+#define NB6_TEMP_REG 0x22
+#define NB6_VOLTAGE_REG 0x24
+#define NB6_DMESG_CTL_REG 0x26
+#define NB6_DMESG_VAL_REG 0x27
+#define NB6_LEDS_MODE_REG 0x31
+#define NB6_RELEASE_REG 0x90
+#define NB6_STATS_BOOT_REG 0xa0
+#define NB6_STATS_PANIC_REG 0xa1
+#define NB6_STATS_OOPS_REG 0xa2
+#define NB6_WDT_REG 0xee
+
+#define NB6_DELAY 1000
+#define NB6_DMESG_SIZE 512
+#define NB6_I2C_RETRIES 5
+#define NB6_LEDS_MODE_LEN 32
+#define NB6_LEDS_PWM_COUNT 9
+#define NB6_PWM(x) (NB6_LEDS_PWM_REG + x)
+#define NB6_WDT_LEN 10
+
+#define ADC_quantum(Vref) ((1000 * (Vref)) / 1024)
+#define ADC_mV(Vref,x) ((ADC_quantum(Vref) * (x)) / 1000)
+#define ADC_Temperature(t) (1000 * (100 * ADC_mV(1800, t)) / 349)
+#define MR1 82
+#define MR2 20
+#define ADC_Voltage(v) ((ADC_mV(2400, v) * ((10 * (MR1 + MR2)) / MR2)) / 10)
+
+struct nb6_data {
+ struct pwm_chip pwm;
+ struct i2c_client *i2c;
+ struct device *dev;
+ struct mutex lock;
+ u8 leds_mode;
+ u8 leds_pwm[NB6_LEDS_PWM_COUNT];
+ u8 release;
+ u8 stats_boot;
+ u8 stats_panic;
+ u8 stats_oops;
+ u16 temperature;
+ u16 voltage;
+ u8 watchdog;
+};
+
+enum LEDS_MODE {
+ LEDS_MODE_DISABLE,
+ LEDS_MODE_BOOT,
+ LEDS_MODE_BOOT_MAIN,
+ LEDS_MODE_BOOT_TFTP,
+ LEDS_MODE_BOOT_RESCUE,
+ LEDS_MODE_LOGIN,
+ LEDS_MODE_BURNING,
+ LEDS_MODE_DOWNLOAD,
+ LEDS_MODE_WDT_TEMPERATURE,
+ LEDS_MODE_WDT_VOLTAGE,
+ LEDS_MODE_PANIC,
+ LEDS_MODE_CONTROL,
+ LEDS_MODE_NUM
+};
+
+static char const *leds_modes_str[] = {
+ [LEDS_MODE_DISABLE] = "disable",
+ [LEDS_MODE_BOOT] = "boot",
+ [LEDS_MODE_BOOT_MAIN] = "boot-main",
+ [LEDS_MODE_BOOT_TFTP] = "boot-tftp",
+ [LEDS_MODE_BOOT_RESCUE] = "boot-rescue",
+ [LEDS_MODE_LOGIN] = "login",
+ [LEDS_MODE_BURNING] = "burning",
+ [LEDS_MODE_DOWNLOAD] = "downloading",
+ [LEDS_MODE_WDT_TEMPERATURE] = "wdt-temperature",
+ [LEDS_MODE_WDT_VOLTAGE] = "wdt-voltage",
+ [LEDS_MODE_PANIC] = "panic",
+ [LEDS_MODE_CONTROL] = "control",
+};
+
+/* I2C Helpers */
+
+static u8 nb6_readb(struct nb6_data *data, u8 addr, u8 val)
+{
+ int status;
+ unsigned i;
+
+ for (i = 0; i < NB6_I2C_RETRIES; i++) {
+ status = i2c_smbus_read_byte_data(data->i2c, addr);
+ if (status >= 0)
+ return status;
+ udelay(NB6_DELAY);
+ }
+
+ dev_err(data->dev, "read error (%d): addr=0x%02x", status, addr);
+
+ return val;
+}
+
+static u16 nb6_readw(struct nb6_data *data, u8 addr, u16 val)
+{
+ u8 tmp;
+
+ tmp = nb6_readb(data, addr, (val >> 8) & 0xff);
+ val = (val & 0xff) | (tmp << 8);
+
+ tmp = nb6_readb(data, addr + 1, val & 0xff);
+ val = (val & 0xff00) | tmp;
+
+ return val;
+}
+
+static s32 nb6_writeb(struct nb6_data *data, u8 addr, u8 val)
+{
+ int status;
+ unsigned i;
+
+ for (i = 0; i < NB6_I2C_RETRIES; i++) {
+ status = i2c_smbus_write_byte_data(data->i2c, addr, val);
+ if (!status)
+ return 0;
+ udelay(NB6_DELAY);
+ }
+
+ dev_err(data->dev, "write error (%d): addr=0x%02x val=0x%02x", status, addr, val);
+
+ return status;
+}
+
+static inline void leds_mode_update(struct nb6_data *data, u8 val)
+{
+ if ((data->leds_mode != val) &&
+ !nb6_writeb(data, NB6_LEDS_MODE_REG, val))
+ data->leds_mode = val;
+}
+
+static inline void leds_pwm_update(struct nb6_data *data, u8 id, u8 val)
+{
+ if ((data->leds_pwm[id] != val) &&
+ !nb6_writeb(data, NB6_PWM(id), val))
+ data->leds_pwm[id] = val;
+}
+
+/* Hardware Monitoring */
+
+static ssize_t dmesg_show(struct device *dev, struct device_attribute *attr,
+ char *buf)
+{
+ struct nb6_data *data = dev_get_drvdata(dev);
+ unsigned i;
+
+ mutex_lock(&data->lock);
+
+ if (nb6_writeb(data, NB6_DMESG_CTL_REG, 0)) {
+ mutex_unlock(&data->lock);
+ return -EINVAL;
+ }
+
+ for (i = 0; i < NB6_DMESG_SIZE; i++)
+ buf[i] = nb6_readb(data, NB6_DMESG_VAL_REG, ~0);
+
+ mutex_unlock(&data->lock);
+
+ *buf = '\0';
+
+ return i + 1;
+}
+
+static DEVICE_ATTR_RO(dmesg);
+
+static ssize_t leds_mode_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct nb6_data *data = dev_get_drvdata(dev);
+ loff_t off = 0;
+ unsigned i;
+
+ mutex_lock(&data->lock);
+ data->leds_mode = nb6_readb(data, NB6_LEDS_MODE_REG, data->leds_mode);
+ mutex_unlock(&data->lock);
+
+ for (i = 0; i < ARRAY_SIZE(leds_modes_str); i++) {
+ off += sprintf(buf + off,
+ (i == data->leds_mode) ? "[%s] " : "%s ",
+ leds_modes_str[i]);
+ }
+
+ off += sprintf(buf + off, "\n");
+
+ return off;
+}
+
+static ssize_t leds_mode_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct nb6_data *data = dev_get_drvdata(dev);
+ char _s[NB6_LEDS_MODE_LEN];
+ char *s;
+ unsigned i;
+
+ snprintf(_s, sizeof(_s), "%s", buf);
+ s = strstrip(_s);
+ for (i = 0; i < ARRAY_SIZE(leds_modes_str); i++) {
+ if (!strcmp(s, leds_modes_str[i])) {
+ leds_mode_update(data, i);
+ break;
+ }
+ }
+
+ return count;
+}
+
+static DEVICE_ATTR_RW(leds_mode);
+
+static ssize_t release_show(struct device *dev, struct device_attribute *attr,
+ char *buf)
+{
+ struct nb6_data *data = dev_get_drvdata(dev);
+
+ mutex_lock(&data->lock);
+ data->release = nb6_readb(data, NB6_RELEASE_REG, data->release);
+ mutex_unlock(&data->lock);
+
+ return sprintf(buf, "%u\n", data->release);
+}
+
+static DEVICE_ATTR_RO(release);
+
+static ssize_t stats_show(struct device *dev, struct device_attribute *attr,
+ char *buf)
+{
+ struct nb6_data *data = dev_get_drvdata(dev);
+
+ mutex_lock(&data->lock);
+ data->stats_boot = nb6_readb(data, NB6_STATS_BOOT_REG,
+ data->stats_boot);
+ data->stats_panic = nb6_readb(data, NB6_STATS_PANIC_REG,
+ data->stats_panic);
+ data->stats_oops = nb6_readb(data, NB6_STATS_OOPS_REG,
+ data->stats_oops);
+ mutex_unlock(&data->lock);
+
+ return sprintf(buf, "boot: %u\npanic: %u\noops: %u\n",
+ data->stats_boot, data->stats_panic, data->stats_oops);
+}
+
+static DEVICE_ATTR_RO(stats);
+
+static ssize_t temperature_show(struct device *dev,
+ struct device_attribute *da, char *buf)
+{
+ struct nb6_data *data = dev_get_drvdata(dev);
+
+ mutex_lock(&data->lock);
+ data->temperature = nb6_readw(data, NB6_TEMP_REG, data->temperature);
+ mutex_unlock(&data->lock);
+
+ return sprintf(buf, "%u\n", ADC_Temperature(data->temperature));
+}
+
+static DEVICE_ATTR_RO(temperature);
+
+static ssize_t voltage_show(struct device *dev, struct device_attribute *attr,
+ char *buf)
+{
+ struct nb6_data *data = dev_get_drvdata(dev);
+
+ mutex_lock(&data->lock);
+ data->voltage = nb6_readw(data, NB6_VOLTAGE_REG, data->voltage);
+ mutex_unlock(&data->lock);
+
+ return sprintf(buf, "%u\n", ADC_Voltage(data->voltage));
+}
+
+static DEVICE_ATTR_RO(voltage);
+
+static ssize_t watchdog_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct nb6_data *data = dev_get_drvdata(dev);
+
+ mutex_lock(&data->lock);
+ data->watchdog = nb6_readb(data, NB6_WDT_REG, data->watchdog);
+ mutex_unlock(&data->lock);
+
+ return sprintf(buf, "%u\n", data->watchdog);
+}
+
+static ssize_t watchdog_store(struct device *dev,
+ struct device_attribute *attr, const char *buf,
+ size_t len)
+{
+ struct nb6_data *data = dev_get_drvdata(dev);
+ unsigned long val;
+ int ret;
+
+ ret = kstrtoul(buf, 0, &val);
+ if (ret < 0)
+ return ret;
+
+ mutex_lock(&data->lock);
+ if (!nb6_writeb(data, NB6_WDT_REG, val))
+ data->watchdog = val;
+ mutex_unlock(&data->lock);
+
+ return len;
+}
+
+static DEVICE_ATTR_RW(watchdog);
+
+static struct attribute *nb6_attrs[] = {
+ &dev_attr_dmesg.attr,
+ &dev_attr_leds_mode.attr,
+ &dev_attr_release.attr,
+ &dev_attr_stats.attr,
+ &dev_attr_temperature.attr,
+ &dev_attr_voltage.attr,
+ &dev_attr_watchdog.attr,
+ NULL,
+};
+
+ATTRIBUTE_GROUPS(nb6);
+
+/* PWM */
+
+static inline struct nb6_data *to_nb6_pwm(struct pwm_chip *chip)
+{
+ return container_of(chip, struct nb6_data, pwm);
+}
+
+static int nb6_pwm_request(struct pwm_chip *chip, struct pwm_device *pwm)
+{
+ struct nb6_data *data = to_nb6_pwm(chip);
+
+ mutex_lock(&data->lock);
+ if (!nb6_writeb(data, NB6_PWM(pwm->hwpwm), 0))
+ data->leds_pwm[pwm->hwpwm] = 0;
+ else
+ data->leds_pwm[pwm->hwpwm] = ~0;
+ mutex_unlock(&data->lock);
+
+ return 0;
+}
+
+static void nb6_pwm_free(struct pwm_chip *chip, struct pwm_device *pwm)
+{
+ struct nb6_data *data = to_nb6_pwm(chip);
+ unsigned i;
+
+ mutex_lock(&data->lock);
+ for (i = 0; i < NB6_LEDS_PWM_COUNT; i++) {
+ if (data->leds_pwm[i]) {
+ leds_mode_update(data, LEDS_MODE_DISABLE);
+ break;
+ }
+ }
+ mutex_unlock(&data->lock);
+}
+
+static int nb6_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
+ int duty_ns, int period_ns)
+{
+ struct nb6_data *data = to_nb6_pwm(chip);
+
+ mutex_lock(&data->lock);
+ leds_mode_update(data, LEDS_MODE_CONTROL);
+ leds_pwm_update(data, pwm->hwpwm, duty_ns);
+ mutex_unlock(&data->lock);
+
+ return 0;
+}
+
+static int nb6_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
+{
+ struct nb6_data *data = to_nb6_pwm(chip);
+
+ mutex_lock(&data->lock);
+ leds_mode_update(data, LEDS_MODE_CONTROL);
+ mutex_unlock(&data->lock);
+
+ return 0;
+}
+
+static void nb6_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)
+{
+ struct nb6_data *data = to_nb6_pwm(chip);
+
+ mutex_lock(&data->lock);
+ leds_pwm_update(data, pwm->hwpwm, 0);
+ mutex_unlock(&data->lock);
+}
+
+static const struct pwm_ops nb6_pwm_ops = {
+ .request = nb6_pwm_request,
+ .free = nb6_pwm_free,
+ .config = nb6_pwm_config,
+ .enable = nb6_pwm_enable,
+ .disable = nb6_pwm_disable,
+ .owner = THIS_MODULE,
+};
+
+/* Driver */
+
+static int nb6_hwmon_probe(struct i2c_client *client,
+ const struct i2c_device_id *id)
+{
+ struct device *dev = &client->dev;
+ struct nb6_data *data;
+ struct device *hwmon_dev;
+ int ret;
+
+ data = devm_kzalloc(dev, sizeof(struct nb6_data), GFP_KERNEL);
+ if (!data)
+ return -ENOMEM;
+
+ data->dev = dev;
+ data->i2c = client;
+ data->leds_mode = LEDS_MODE_NUM;
+ i2c_set_clientdata(client, data);
+ mutex_init(&data->lock);
+
+ hwmon_dev = devm_hwmon_device_register_with_groups(dev, client->name,
+ data,
+ nb6_groups);
+ if (IS_ERR(hwmon_dev))
+ return PTR_ERR(hwmon_dev);
+
+ data->pwm.dev = dev;
+ data->pwm.ops = &nb6_pwm_ops;
+ data->pwm.base = -1;
+ data->pwm.npwm = NB6_LEDS_PWM_COUNT;
+
+ ret = pwmchip_add(&data->pwm);
+ if (ret < 0)
+ return ret;
+
+ return 0;
+};
+
+static const struct of_device_id nb6_hwmon_of_match[] = {
+ { .compatible = "sfr,nb6_hwmon" },
+ { },
+};
+MODULE_DEVICE_TABLE(of, nb6_hwmon_of_match);
+
+static struct i2c_driver nb6_hwmon_driver = {
+ .class = I2C_CLASS_HWMON,
+ .driver = {
+ .name = "nb6-hwmon",
+ .of_match_table = of_match_ptr(nb6_hwmon_of_match),
+ },
+ .probe = nb6_hwmon_probe,
+};
+module_i2c_driver(nb6_hwmon_driver);
--
2.26.2