[PATCH v2 1/2] powerpc/powernv: Add poweroff (EPOW, DPO) events support for PowerNV platform

[Stewart Smith]

trigg <mr.triggtrigg at gmail.com> writes:
>> --- a/arch/powerpc/include/asm/opal-api.h
>> +++ b/arch/powerpc/include/asm/opal-api.h
>> @@ -730,6 +730,36 @@ struct opal_i2c_request {
>>         __be64 buffer_ra;               /* Buffer real address */
>>  };
>>
>> +/*
>> + * EPOW status sharing (OPAL and the host)
>> + *
>> + * The host will pass on OPAL, a buffer of length OPAL_EPOW_MAX_CLASSES
>> + * to fetch system wide EPOW status. Each element in the returned buffer
>> + * will contain bitwise EPOW status for each EPOW sub class.
>> + */
>> +
>> +/* EPOW types */
>> +enum OpalEpow {
>> +       OPAL_EPOW_POWER         = 0,    /* Power EPOW */
>> +       OPAL_EPOW_TEMP          = 1,    /* Temperature EPOW */
>> +       OPAL_EPOW_COOLING       = 2,    /* Cooling EPOW */
>> +       OPAL_MAX_EPOW_CLASSES   = 3,    /* Max EPOW categories */
>> +};
> Dont explicitly assign sequential numbers in an enum. Its taken care
> of by the compiler.

This header is shared with firmware, and the exact values of each item
does matter as it's ABI. The explicit numbers means that people think
twice before inserting a new value in the middle and subtley breaking
firmware ABI.