• Bob Moore's avatar
    ACPICA: Update to GPIO region handler interface. · 75ec6e55
    Bob Moore authored
    Changes to correct several GPIO issues:
    
    1) The update_rule in a GPIO field definition is now ignored;
    a read-modify-write operation is never performed for GPIO fields.
    (Internally, this means that the field assembly/disassembly
    code is completely bypassed for GPIO.)
    
    2) The Address parameter passed to a GPIO region handler is
    now the bit offset of the field from a previous Connection()
    operator. Thus, it becomes a "Pin Number Index" into the
    Connection() resource descriptor.
    
    3) The bit_width parameter passed to a GPIO region handler is
    now the exact bit width of the GPIO field. Thus, it can be
    interpreted as "number of pins".
    
    Overall, we can now say that the region handler interface
    to GPIO handlers is a raw "bit/pin" addressed interface, not
    a byte-addressed interface like the system_memory handler interface.
    Signed-off-by: default avatarBob Moore <robert.moore@intel.com>
    Signed-off-by: default avatarLv Zheng <lv.zheng@intel.com>
    Cc: 3.15+ <stable@vger.kernel.org> # 3.15+
    Signed-off-by: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
    75ec6e55
evregion.c 23 KB