Re: [PATCH 1/2] pinctrl: mediatek: Ignore interrupts that are wake only during resume
From: Sean Wang <sean.wang@kernel.org>
Date: 2019-06-21 04:47:32
Also in:
linux-gpio, linux-mediatek, lkml
Hi Nicolas, On Sun, Apr 28, 2019 at 8:55 PM Nicolas Boichat [off-list ref] wrote:
Before suspending, mtk-eint would set the interrupt mask to the
one in wake_mask. However, some of these interrupts may not have a
corresponding interrupt handler, or the interrupt may be disabled.
On resume, the eint irq handler would trigger nevertheless,
and irq/pm.c:irq_pm_check_wakeup would be called, which would
try to call irq_disable. However, if the interrupt is not enabled
(irqd_irq_disabled(&desc->irq_data) is true), the call does nothing,
and the interrupt is left enabled in the eint driver.
Especially for level-sensitive interrupts, this will lead to an
interrupt storm on resume.
If we detect that an interrupt is only in wake_mask, but not in
cur_mask, we can just mask it out immediately (as mtk_eint_resume
would do anyway at a later stage in the resume sequence, when
restoring cur_mask).
Fixes: bf22ff45bed ("genirq: Avoid unnecessary low level irq function calls")
Signed-off-by: Nicolas Boichat <redacted>Acked-by: Sean Wang <sean.wang@kernel.org>
quoted hunk ↗ jump to hunk
--- drivers/pinctrl/mediatek/mtk-eint.c | 16 +++++++++++++++- 1 file changed, 15 insertions(+), 1 deletion(-)diff --git a/drivers/pinctrl/mediatek/mtk-eint.c b/drivers/pinctrl/mediatek/mtk-eint.c index f464f8cd274b75c..737385e86beb807 100644 --- a/drivers/pinctrl/mediatek/mtk-eint.c +++ b/drivers/pinctrl/mediatek/mtk-eint.c@@ -318,7 +318,7 @@ static void mtk_eint_irq_handler(struct irq_desc *desc) struct irq_chip *chip = irq_desc_get_chip(desc); struct mtk_eint *eint = irq_desc_get_handler_data(desc); unsigned int status, eint_num; - int offset, index, virq; + int offset, mask_offset, index, virq; void __iomem *reg = mtk_eint_get_offset(eint, 0, eint->regs->stat); int dual_edge, start_level, curr_level;@@ -328,10 +328,24 @@ static void mtk_eint_irq_handler(struct irq_desc *desc) status = readl(reg); while (status) { offset = __ffs(status); + mask_offset = eint_num >> 5; index = eint_num + offset; virq = irq_find_mapping(eint->domain, index); status &= ~BIT(offset); + /* + * If we get an interrupt on pin that was only required + * for wake (but no real interrupt requested), mask the + * interrupt (as would mtk_eint_resume do anyway later + * in the resume sequence). + */ + if (eint->wake_mask[mask_offset] & BIT(offset) && + !(eint->cur_mask[mask_offset] & BIT(offset))) { + writel_relaxed(BIT(offset), reg - + eint->regs->stat + + eint->regs->mask_set); + } + dual_edge = eint->dual_edge[index]; if (dual_edge) { /* --2.21.0.593.g511ec345e18-goog
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