• Dave Martin's avatar
    ARM: 6940/1: fiq: Briefly document driver responsibilities for suspend/resume · 2846d84f
    Dave Martin authored
    Drivers which make use of the FIQ interrupt may require the state
    of the FIQ mode registers to be preserved across suspend/resume.
    
    Because the FIQ mode registers are not saved and restored
    automatically by the kernel, driver authors will need to do the
    appropriate save/restore in their own driver suspend/resume
    handlers.
    
    Implementing global automatic save/restore of the FIQ state does
    not appear appropriate, since this by itself is not sufficient for
    FIQ-based drivers to function correctly across suspend/resume in
    any case.
    
    This patch adds a brief explanatory note to fiq.h documenting the
    requirement placed on driver authors.
    Signed-off-by: default avatarDave Martin <dave.martin@linaro.org>
    Signed-off-by: default avatarRussell King <rmk+kernel@arm.linux.org.uk>
    2846d84f
fiq.h 1.32 KB