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Diffstat (limited to 'Documentation/wmi/devices/dell-wmi-ddv.rst')
| -rw-r--r-- | Documentation/wmi/devices/dell-wmi-ddv.rst | 46 |
1 files changed, 34 insertions, 12 deletions
diff --git a/Documentation/wmi/devices/dell-wmi-ddv.rst b/Documentation/wmi/devices/dell-wmi-ddv.rst index e0c20af30948..109d4c5c922e 100644 --- a/Documentation/wmi/devices/dell-wmi-ddv.rst +++ b/Documentation/wmi/devices/dell-wmi-ddv.rst @@ -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() -------------------------------- @@ -153,7 +150,40 @@ Returns the voltage flow of the battery in mV as an u16. WMI method BatteryManufactureAccess() ------------------------------------- -Returns a manufacture-defined value as an u16. +Returns the health status of the battery as a u16. +The health status encoded in the following manner: + + - the third nibble contains the general failure mode + - the fourth nibble contains the specific failure code + +Valid failure modes are: + + - permanent failure (``0x9``) + - overheat failure (``0xa``) + - overcurrent failure (``0xb``) + +All other failure modes are to be considered normal. + +The following failure codes are valid for a permanent failure: + + - fuse blown (``0x0``) + - cell imbalance (``0x1``) + - overvoltage (``0x2``) + - fet failure (``0x3``) + +The last two bits of the failure code are to be ignored when the battery +signals a permanent failure. + +The following failure codes a valid for a overheat failure: + + - overheat at start of charging (``0x5``) + - overheat during charging (``0x7``) + - overheat during discharging (``0x8``) + +The following failure codes are valid for a overcurrent failure: + + - overcurrent during charging (``0x6``) + - overcurrent during discharging (``0xb``) WMI method BatteryRelativeStateOfCharge() ----------------------------------------- @@ -260,14 +290,6 @@ Some machines like the Dell Inspiron 3505 only support a single battery and thus ignore the battery index. Because of this the driver depends on the ACPI battery hook mechanism to discover batteries. -.. note:: - The ACPI battery matching algorithm currently used inside the driver is - outdated and does not match the algorithm described above. The reasons for - this are differences in the handling of the ToHexString() ACPI opcode between - Linux and Windows, which distorts the serial number of ACPI batteries on many - machines. Until this issue is resolved, the driver cannot use the above - algorithm. - Reverse-Engineering the DDV WMI interface ========================================= |