4.4-stable review patch. If anyone has any objections, please let me know.
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From: Tony Lindgren tony@atomide.com
[ Upstream commit d3be6d2a08bd26580562d9714d3d97ea9ba22c73 ]
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: Grygorii Strashko grygorii.strashko@ti.com Cc: Tero Kristo t-kristo@ti.com Signed-off-by: Tony Lindgren tony@atomide.com Signed-off-by: Sasha Levin alexander.levin@microsoft.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- arch/arm/mach-omap2/pm.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
--- a/arch/arm/mach-omap2/pm.c +++ b/arch/arm/mach-omap2/pm.c @@ -231,7 +231,7 @@ static void omap_pm_end(void) cpu_idle_poll_ctrl(false); }
-static void omap_pm_finish(void) +static void omap_pm_wake(void) { if (cpu_is_omap34xx()) omap_prcm_irq_complete(); @@ -241,7 +241,7 @@ static const struct platform_suspend_ops .begin = omap_pm_begin, .end = omap_pm_end, .enter = omap_pm_enter, - .finish = omap_pm_finish, + .wake = omap_pm_wake, .valid = suspend_valid_only_mem, };