From 353d6d6c82e5d2533ba22e7f9fb081582bf50dc2 Mon Sep 17 00:00:00 2001 From: Thomas Petazzoni Date: Wed, 21 Oct 2015 15:48:15 +0200 Subject: [PATCH] irqchip/armada-370-xp: Fix regression by clearing IRQ_NOAUTOEN Commit d17cab4451df1 ("irqchip: Kill off set_irq_flags usage") changed the code of armada_370_xp_mpic_irq_map() from using set_irq_flags() to irq_set_probe(). While the commit log seems to imply that there are no functional changes, there are indeed functional changes introduced by this commit: the IRQ_NOAUTOEN flag is no longer cleared. This functional change causes a regression on Armada XP, which no longer works properly after suspend/resume because per-CPU interrupts remain disabled. Due to how the hardware registers work, the irq-armada-370-xp cannot simply save/restore a bunch of registers at suspend/resume to make sure that the interrupts remain in the same state after resuming. Therefore, it relies on the kernel to say whether the interrupt is disabled or not, using the irqd_irq_disabled() function. This was all working fine while the IRQ_NOAUTOEN flag was cleared. With the change introduced by Rob Herring in d17cab4451df1, the IRQ_NOAUTOEN flag is now set for all interrupts. irqd_irq_disabled() returns false for per-CPU interrupts, and therefore our per-CPU interrupts are no longer re-enabled after resume. This commit works around this problem by clearing again the IRQ_NOAUTOEN flags, so that we are back to the situation we had before commit d17cab4451df1. This work around is proposed as a minimal fix for the problem, while a better long-term solution is being worked on. Fixes: d17cab4451df1 "irqchip: Kill off set_irq_flags usage" Signed-off-by: Thomas Petazzoni Link: https://lkml.kernel.org/r/1445435295-19956-1-git-send-email-thomas.petazzoni@free-electrons.com Signed-off-by: Jason Cooper Signed-off-by: Thomas Gleixner --- drivers/irqchip/irq-armada-370-xp.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/irqchip/irq-armada-370-xp.c b/drivers/irqchip/irq-armada-370-xp.c index 655cb967a1f2..389318a3be82 100644 --- a/drivers/irqchip/irq-armada-370-xp.c +++ b/drivers/irqchip/irq-armada-370-xp.c @@ -317,6 +317,7 @@ static int armada_370_xp_mpic_irq_map(struct irq_domain *h, handle_level_irq); } irq_set_probe(virq); + irq_clear_status_flags(virq, IRQ_NOAUTOEN); return 0; } -- 2.20.1