2017-06-22 16:44 GMT+03:00 Guenter Roeck <linux@xxxxxxxxxxxx>: > On 06/22/2017 05:07 AM, Kirill Esipov wrote: >> >> >> >> 2017-06-22 1:24 GMT+03:00 Guenter Roeck <linux@xxxxxxxxxxxx >> <mailto:linux@xxxxxxxxxxxx>>: >> >> On Wed, Jun 21, 2017 at 05:49:43PM +0300, Kirill Esipov wrote: >> > DS3232/DS3234 has the temperature registers with a resolution of >> > 0.25 degree celsius. This enables to get the value through hwmon. >> > >> > # cat /sys/class/hwmon/hwmon0/temp1_input >> > 37250 >> > >> > Signed-off-by: Kirill Esipov <yesipov@xxxxxxxxx >> <mailto:yesipov@xxxxxxxxx>> >> >> > --- >> > drivers/rtc/Kconfig | 9 ++++++ >> > drivers/rtc/rtc-ds3232.c | 84 >> ++++++++++++++++++++++++++++++++++++++++++++++++ >> > 2 files changed, 93 insertions(+) >> > >> > diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig >> > index 8d3b95728326..b4a6a916d4df 100644 >> > --- a/drivers/rtc/Kconfig >> > +++ b/drivers/rtc/Kconfig >> > @@ -791,6 +791,15 @@ config RTC_DRV_DS3232 >> > This driver can also be built as a module. If so, the >> module >> > will be called rtc-ds3232. >> > >> > +config RTC_DRV_DS3232_HWMON >> > + bool "HWMON support for Dallas/Maxim DS3232/DS3234" >> > + depends on RTC_DRV_DS3232 && HWMON >> > + depends on !(RTC_DRV_DS3232=y && HWMON=m) >> > + default y >> > + help >> > + Say Y here if you want to expose temperature sensor data on >> > + rtc-ds3232 >> > + >> > config RTC_DRV_PCF2127 >> > tristate "NXP PCF2127" >> > depends on RTC_I2C_AND_SPI >> > diff --git a/drivers/rtc/rtc-ds3232.c b/drivers/rtc/rtc-ds3232.c >> > index deff431a37c4..f94ff0685942 100644 >> > --- a/drivers/rtc/rtc-ds3232.c >> > +++ b/drivers/rtc/rtc-ds3232.c >> > @@ -22,6 +22,8 @@ >> > #include <linux/bcd.h> >> > #include <linux/slab.h> >> > #include <linux/regmap.h> >> > +#include <linux/hwmon.h> >> > +#include <linux/hwmon-sysfs.h> >> > >> > #define DS3232_REG_SECONDS 0x00 >> > #define DS3232_REG_MINUTES 0x01 >> > @@ -275,6 +277,86 @@ static int ds3232_update_alarm(struct device >> *dev, unsigned int enabled) >> > return ret; >> > } >> > >> > >> +/*----------------------------------------------------------------------*/ >> > + >> > +#ifdef CONFIG_RTC_DRV_DS3232_HWMON >> > + >> > +/* >> > + * Temperature sensor support for ds3232/ds3234 devices. >> > + */ >> > + >> > +#define DS3232_REG_TEMPERATURE 0x11 >> > + >> > +/* >> > + * A user-initiated temperature conversion is not started by this >> function, >> > + * so the temperature is updated once every 64 seconds. >> > + */ >> > +static int ds3232_hwmon_read_temp(struct device *dev, s32 *mC) >> > +{ >> > + struct ds3232 *ds3232 = dev_get_drvdata(dev); >> > + u8 temp_buf[2]; >> > + s16 temp; >> > + int ret; >> > + >> > + ret = regmap_bulk_read(ds3232->regmap, >> DS3232_REG_TEMPERATURE, temp_buf, >> > + sizeof(temp_buf)); >> > + >> > + if (ret < 0) >> > + return ret; >> > + >> > + /* >> > + * Temperature is represented as a 10-bit code with a >> resolution of >> > + * 0.25 degree celsius and encoded in two's complement >> format. >> > + */ >> > + temp = (temp_buf[0] << 8) | temp_buf[1]; >> > + temp >>= 6; >> > + *mC = temp * 250; >> > + >> > + return 0; >> > +} >> > + >> > +static ssize_t ds3232_hwmon_show_temp(struct device *dev, >> > + struct device_attribute *attr, char >> *buf) >> > +{ >> > + int ret; >> > + s32 temp; >> > + >> > + ret = ds3232_hwmon_read_temp(dev, &temp); >> > + if (ret < 0) >> > + return ret; >> > + >> > + return sprintf(buf, "%d\n", temp); >> > +} >> > +static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, >> ds3232_hwmon_show_temp, >> > + NULL, 0); >> > + >> > +static struct attribute *ds3232_hwmon_attrs[] = { >> > + &sensor_dev_attr_temp1_input.dev_attr.attr, >> > + NULL, >> > +}; >> > +ATTRIBUTE_GROUPS(ds3232_hwmon); >> > + >> > +static void ds3232_hwmon_register(struct device *dev, const char >> *name) >> > +{ >> > + struct ds3232 *ds3232 = dev_get_drvdata(dev); >> > + struct device *hwmon_dev; >> > + >> > + hwmon_dev = devm_hwmon_device_register_with_groups(dev, name, >> ds3232, >> > + >> ds3232_hwmon_groups); >> >> Any reason for not using devm_hwmon_device_register_with_info() ? >> >> >> >> Just to keep uniformity, because other rtc drivers with hwmon >> (rtc-ds1307, rtc-rv3029c2) use >> devm_hwmon_device_register_with_groups(). >> > > Hmm. Odd reason. With this line of argument, a new API should never be used > because "everyone else uses the old API". Well, I had task to add temperature feature to my device, and the cheapest (easiest) way was to make it as in same device drivers. I did it and decided to share. > How about converting the other drivers to use new API instead ? Ok, at first I'll try to use new hwmon API for current driver (rtc-ds3232) . > The idea behind the new API was to simplify drivers and make them > independent > of the sysfs ABI. That doesn't mean that drivers _have_ to use that API, > though, > so feel free to stick with the above. > > Guenter > > >> >> Guenter >> >> > + if (IS_ERR(hwmon_dev)) { >> > + dev_warn(dev, "unable to register hwmon device >> %ld\n", >> > + PTR_ERR(hwmon_dev)); >> > + } >> > +} >> > + >> > +#else >> > + >> > +static void ds3232_hwmon_register(struct ds3232 *ds3232) >> > +{ >> > +} >> > + >> > +#endif >> > + >> > static int ds3232_alarm_irq_enable(struct device *dev, unsigned >> int enabled) >> > { >> > struct ds3232 *ds3232 = dev_get_drvdata(dev); >> > @@ -366,6 +448,8 @@ static int ds3232_probe(struct device *dev, >> struct regmap *regmap, int irq, >> > if (ds3232->irq > 0) >> > device_init_wakeup(dev, 1); >> > >> > + ds3232_hwmon_register(dev, name); >> > + >> > ds3232->rtc = devm_rtc_device_register(dev, name, >> &ds3232_rtc_ops, >> > THIS_MODULE); >> > if (IS_ERR(ds3232->rtc)) >> >> >> >> >> -- >> Kirill Esipov > > -- Kirill Esipov
