Unverified Commit 303ecf69 authored by Armin Wolf's avatar Armin Wolf Committed by Ilpo Järvinen
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platform/x86: dell-ddv: Expose the battery manufacture date to userspace 



The manufacture date of a given battery is exposed over the Dell DDV
WMI interface using the "BatteryManufactureDate" WMI method. The
resulting data contains the manufacture date of the battery encoded
inside a 16-bit value as described in the Smart Battery Data
Specification.

Expose this value to userspace using the power supply extension
interface.

Tested on a Dell Inspiron 3505.

Signed-off-by: default avatarArmin Wolf <W_Armin@gmx.de>
Link: https://lore.kernel.org/r/20250429003606.303870-3-W_Armin@gmx.de


Reviewed-by: default avatarIlpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: default avatarIlpo Järvinen <ilpo.jarvinen@linux.intel.com>
parent 058de163

Documentation/wmi/devices/dell-wmi-ddv.rst

+0 −3
Original line number Diff line number Diff line
@@ -118,9 +118,6 @@ The date is encoded in the following manner: 
- bits 5 to 8 contain the manufacture month.

- bits 9 to 15 contain the manufacture year biased by 1980.



.. note::

   The data format needs to be verified on more machines.



WMI method BatterySerialNumber()

--------------------------------

drivers/platform/x86/dell/dell-wmi-ddv.c

+56 −0
Original line number Diff line number Diff line
@@ -8,6 +8,7 @@ 
#define pr_format(fmt) KBUILD_MODNAME ": " fmt



#include <linux/acpi.h>

#include <linux/bitfield.h>

#include <linux/debugfs.h>

#include <linux/device.h>

#include <linux/device/driver.h>
@@ -42,6 +43,10 @@ 
/* Battery indices 1, 2 and 3 */

#define DELL_DDV_NUM_BATTERIES		3



#define SBS_MANUFACTURE_YEAR_MASK	GENMASK(15, 9)

#define SBS_MANUFACTURE_MONTH_MASK	GENMASK(8, 5)

#define SBS_MANUFACTURE_DAY_MASK	GENMASK(4, 0)



#define DELL_EPPID_LENGTH	20

#define DELL_EPPID_EXT_LENGTH	23
@@ -744,6 +749,50 @@ static ssize_t eppid_show(struct device *dev, struct device_attribute *attr, cha 
	return ret;

}



static int dell_wmi_ddv_get_manufacture_date(struct dell_wmi_ddv_data *data, u32 index,

					     enum power_supply_property psp,

					     union power_supply_propval *val)

{

	u16 year, month, day;

	u32 value;

	int ret;



	ret = dell_wmi_ddv_query_integer(data->wdev, DELL_DDV_BATTERY_MANUFACTURE_DATE,

					 index, &value);

	if (ret < 0)

		return ret;

	if (value > U16_MAX)

		return -ENXIO;



	/*

	 * Some devices report a invalid manufacture date value

	 * like 0.0.1980. Because of this we have to check the

	 * whole value before exposing parts of it to user space.

	 */

	year = FIELD_GET(SBS_MANUFACTURE_YEAR_MASK, value) + 1980;

	month = FIELD_GET(SBS_MANUFACTURE_MONTH_MASK, value);

	if (month < 1 || month > 12)

		return -ENODATA;



	day = FIELD_GET(SBS_MANUFACTURE_DAY_MASK, value);

	if (day < 1 || day > 31)

		return -ENODATA;



	switch (psp) {

	case POWER_SUPPLY_PROP_MANUFACTURE_YEAR:

		val->intval = year;

		return 0;

	case POWER_SUPPLY_PROP_MANUFACTURE_MONTH:

		val->intval = month;

		return 0;

	case POWER_SUPPLY_PROP_MANUFACTURE_DAY:

		val->intval = day;

		return 0;

	default:

		return -EINVAL;

	}

}



static int dell_wmi_ddv_get_property(struct power_supply *psy, const struct power_supply_ext *ext,

				     void *drvdata, enum power_supply_property psp,

				     union power_supply_propval *val)
@@ -768,6 +817,10 @@ static int dell_wmi_ddv_get_property(struct power_supply *psy, const struct powe 
		 */

		val->intval = value - 2732;

		return 0;

	case POWER_SUPPLY_PROP_MANUFACTURE_YEAR:

	case POWER_SUPPLY_PROP_MANUFACTURE_MONTH:

	case POWER_SUPPLY_PROP_MANUFACTURE_DAY:

		return dell_wmi_ddv_get_manufacture_date(data, index, psp, val);

	default:

		return -EINVAL;

	}
@@ -775,6 +828,9 @@ static int dell_wmi_ddv_get_property(struct power_supply *psy, const struct powe 


static const enum power_supply_property dell_wmi_ddv_properties[] = {

	POWER_SUPPLY_PROP_TEMP,

	POWER_SUPPLY_PROP_MANUFACTURE_YEAR,

	POWER_SUPPLY_PROP_MANUFACTURE_MONTH,

	POWER_SUPPLY_PROP_MANUFACTURE_DAY,

};



static const struct power_supply_ext dell_wmi_ddv_extension = {