From 5ae0c7ad06f4386d253ff2120ea769f01292f37b Mon Sep 17 00:00:00 2001 From: Doug Anderson Date: Mon, 26 Jan 2015 08:24:03 -0800 Subject: [PATCH] pinctrl: rockchip: Only mask interrupts; never disable The Rockchip GPIO interrupt controller totally throws away all status about an interrupt when you "disable" the interrupt. That has unfortunate consequences in the following situation: 1. An edge-triggered interrupt is enabled and should wake the system. 2. System suspend happens: interrupt is disabled and marked for wake. 3. rockchip_irq_suspend() reenables the interrupt so we can wake. 4. Interrupt happens when asleep. 5. rockchip_irq_resume() redisables the interrupt. 6. Disabling the interrupt throws away all status about it. 7. Normal system resume happens and we enable the interrupt again, since we threw away status about the interrupt we don't know it fired while suspended. Even worse: if we need both edges of the interrupt the logic to swap edges never runs. Note: even if we somehow can post the status about wakeup interrupts in rockchip_irq_resume() we would still have a window of losing any edges that came in while interrupts were disabled. If we use mask only then we don't need to worry. The GPIO Interrupt controller keeps track of pending interrupts that are enabled and just masked. There was no real strong reason to support the enable/disable functionality (other than that it seemed right), so let's go back to just supporting mask/unmask but actually map it to the real mask/unmask. This ends up with slightly different (and more correct) behavior than before (f2dd028 pinctrl: rockchip: Fix enable/disable/mask/unmask). Signed-off-by: Doug Anderson Reviewed-by: Heiko Stuebner Signed-off-by: Linus Walleij --- drivers/pinctrl/pinctrl-rockchip.c | 48 ++++++++---------------------- 1 file changed, 13 insertions(+), 35 deletions(-) diff --git a/drivers/pinctrl/pinctrl-rockchip.c b/drivers/pinctrl/pinctrl-rockchip.c index d144330a4865..dee7d5f06c60 100644 --- a/drivers/pinctrl/pinctrl-rockchip.c +++ b/drivers/pinctrl/pinctrl-rockchip.c @@ -89,7 +89,7 @@ struct rockchip_iomux { * @reg_pull: optional separate register for additional pull settings * @clk: clock of the gpio bank * @irq: interrupt of the gpio bank - * @saved_enables: Saved content of GPIO_INTEN at suspend time. + * @saved_masks: Saved content of GPIO_INTEN at suspend time. * @pin_base: first pin number * @nr_pins: number of pins in this bank * @name: name of the bank @@ -108,7 +108,7 @@ struct rockchip_pin_bank { struct regmap *regmap_pull; struct clk *clk; int irq; - u32 saved_enables; + u32 saved_masks; u32 pin_base; u8 nr_pins; char *name; @@ -1545,8 +1545,8 @@ static void rockchip_irq_suspend(struct irq_data *d) struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d); struct rockchip_pin_bank *bank = gc->private; - bank->saved_enables = irq_reg_readl(gc, GPIO_INTEN); - irq_reg_writel(gc, gc->wake_active, GPIO_INTEN); + bank->saved_masks = irq_reg_readl(gc, GPIO_INTMASK); + irq_reg_writel(gc, ~gc->wake_active, GPIO_INTMASK); } static void rockchip_irq_resume(struct irq_data *d) @@ -1554,35 +1554,7 @@ static void rockchip_irq_resume(struct irq_data *d) struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d); struct rockchip_pin_bank *bank = gc->private; - irq_reg_writel(gc, bank->saved_enables, GPIO_INTEN); -} - -static void rockchip_irq_disable(struct irq_data *d) -{ - struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d); - u32 val; - - irq_gc_lock(gc); - - val = irq_reg_readl(gc, GPIO_INTEN); - val &= ~d->mask; - irq_reg_writel(gc, val, GPIO_INTEN); - - irq_gc_unlock(gc); -} - -static void rockchip_irq_enable(struct irq_data *d) -{ - struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d); - u32 val; - - irq_gc_lock(gc); - - val = irq_reg_readl(gc, GPIO_INTEN); - val |= d->mask; - irq_reg_writel(gc, val, GPIO_INTEN); - - irq_gc_unlock(gc); + irq_reg_writel(gc, bank->saved_masks, GPIO_INTMASK); } static int rockchip_interrupts_register(struct platform_device *pdev, @@ -1620,6 +1592,14 @@ static int rockchip_interrupts_register(struct platform_device *pdev, continue; } + /* + * Linux assumes that all interrupts start out disabled/masked. + * Our driver only uses the concept of masked and always keeps + * things enabled, so for us that's all masked and all enabled. + */ + writel_relaxed(0xffffffff, bank->reg_base + GPIO_INTMASK); + writel_relaxed(0xffffffff, bank->reg_base + GPIO_INTEN); + gc = irq_get_domain_generic_chip(bank->domain, 0); gc->reg_base = bank->reg_base; gc->private = bank; @@ -1628,8 +1608,6 @@ static int rockchip_interrupts_register(struct platform_device *pdev, gc->chip_types[0].chip.irq_ack = irq_gc_ack_set_bit; gc->chip_types[0].chip.irq_mask = irq_gc_mask_set_bit; gc->chip_types[0].chip.irq_unmask = irq_gc_mask_clr_bit; - gc->chip_types[0].chip.irq_enable = rockchip_irq_enable; - gc->chip_types[0].chip.irq_disable = rockchip_irq_disable; gc->chip_types[0].chip.irq_set_wake = irq_gc_set_wake; gc->chip_types[0].chip.irq_suspend = rockchip_irq_suspend; gc->chip_types[0].chip.irq_resume = rockchip_irq_resume; -- 2.20.1