• Tony Lindgren's avatar
    ARM: OMAP3: Fix prm wake interrupt for resume · d3be6d2a
    Tony Lindgren authored
    For platform_suspend_ops, the finish call is too late to re-enable wake
    irqs and we need re-enable wake irqs on wake call instead.
    
    Otherwise noirq resume for devices has already happened. And then
    dev_pm_disarm_wake_irq() has already disabled the dedicated wake irqs
    when the interrupt triggers and the wake irq is never handled.
    
    For devices that are already in PM runtime suspended state when we
    enter suspend this means that a possible wake irq will never trigger.
    
    And this can lead into a situation where a device has a pending padconf
    wake irq, and the device will stay unresponsive to any further wake
    irqs.
    
    This issue can be easily reproduced by setting serial console log level
    to zero, letting the serial console idle, and suspend the system from
    an ssh terminal. Then try to wake up the system by typing to the serial
    console.
    
    Note that this affects only omap3 PRM interrupt as that's currently
    the only omap variant that does anything in omap_pm_wake().
    
    In general, for the wake irqs to work, the interrupt must have either
    IRQF_NO_SUSPEND or IRQF_EARLY_RESUME set for it to trigger before
    dev_pm_disarm_wake_irq() disables the wake irqs.
    Reported-by: default avatarGrygorii Strashko <grygorii.strashko@ti.com>
    Cc: Tero Kristo <t-kristo@ti.com>
    Signed-off-by: default avatarTony Lindgren <tony@atomide.com>
    d3be6d2a
pm.c 5.4 KB