Hi Guenter,
Thanks for your comments, I will reimplement it as MFD.
Regards,
Álvaro.
> El 8 jun 2020, a las 16:03, Guenter Roeck <linux@xxxxxxxxxxxx> escribió:
>
> On 6/7/20 11:25 AM, Álvaro Fernández Rojas wrote:
>> 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: Álvaro Fernández Rojas <noltari@xxxxxxxxx>
>> ---
>> drivers/hwmon/Kconfig | 11 +
>> drivers/hwmon/Makefile | 1 +
>> drivers/hwmon/nb6-hwmon.c | 466 ++++++++++++++++++++++++++++++++++++++
>
> Missing Documentation/hwmon/nb6-hwmon.rst
>
>> 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 should not support LEDs.
>
>> + 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 Álvaro Fernández 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)
>
> This will never return an error.
>
>> +{
>> + 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);
>> + }
>> +
>
> Is that system really that bad ? That needs an explanation.
>
>> + dev_err(data->dev, "read error (%d): addr=0x%02x", status, addr);
>> +
>> + return val;
>
> Obviously this error case was never reached.
>
>> +}
>> +
>> +static u16 nb6_readw(struct nb6_data *data, u8 addr, u16 val)
>
> This will never return an error.
>
>> +{
>> + u8 tmp;
>> +
>> + tmp = nb6_readb(data, addr, (val >> 8) & 0xff);
>
> This ignores any received errors and, worse, converts errors
> into pretty much random data.
>
>> + 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);
>> +
>
> Non-standard attributes need to be explained and their need must be discussed.
>
>> +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);
>> +
>
> I won't accept any attributes not associated with hardware monitoring.
>
>> +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);
>> +
>
> And I will most definitely not accept unexplained non-standard attributes.
>
>> +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);
>> +
>
> This are not standard hardware monitoring attributes.
>
>> +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);
>> +
>
> While there are situations where we accept a watchdog driver as part
> of a hardware monitoring driver, it has to be a standard watchdog
> driver, not a random attribute such as "watchdog" and "status".
>
>> +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,
>> +};
>
> Not a single standard hardware monitoring attribute.
>
>> +
>> +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);
>
> New drivers must use devm_hwmon_device_register_with_info().
>
>> + 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;
>> +
>
> This very much looks like a multi-function chip (hardware monitoring,
> pwm, LEDs, and possibly watchdog) and should be implemented as such.
>
>> + 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);
