One additional reason...
With current code, sleep_states(0) will not be set if compiled without
CONFIG_SUSPEND, which means that S0 will also disappear from
/proc/acpi/sleep. With pre-2.6.23 code it would be listed there.
I think that is even a more relevant change than the display issue and could
possibly even be considered a user-space interface regression.
My proposed patch fixes that too.
Note that the patch currently does not call acpi_get_sleep_type_data for S0,
but (partially from Rafael's comment) I was assuming that for S0 that does
not really matter. If it does, then the patch could easily be adjusted to
include that.
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