From 0c0451e7634564052a045d4398a91ea4ef1f755b Mon Sep 17 00:00:00 2001 From: Grygorii Strashko Date: Tue, 12 Apr 2016 13:52:31 +0300 Subject: [PATCH] gpio: omap: fix irq triggering in smart-idle wakeup mode Now GPIO IRQ loss is observed on dra7-evm after suspend/resume cycle in the following case: extcon_usb1(id_irq) -> pcf8575.gpio1 -> omapgpio6.gpio11 -> gic the extcon_usb1 is wake up source and it enables IRQ wake up for id_irq by calling enable/disable_irq_wake() during suspend/resume which, in turn, causes execution of omap_gpio_wake_enable(). And omap_gpio_wake_enable() will set/clear corresponding bit in GPIO_IRQWAKEN_x register. omapgpio6 configuration after boot - wakeup is enabled for GPIO IRQs by default from omap_gpio_irq_type: GPIO_IRQSTATUS_SET_0 | 0x00000400 GPIO_IRQSTATUS_CLR_0 | 0x00000400 GPIO_IRQWAKEN_0 | 0x00000400 GPIO_RISINGDETECT | 0x00000000 GPIO_FALLINGDETECT | 0x00000400 omapgpio6 configuration after after suspend/resume cycle: GPIO_IRQSTATUS_SET_0 | 0x00000400 GPIO_IRQSTATUS_CLR_0 | 0x00000400 GPIO_IRQWAKEN_0 | 0x00000000 <--- GPIO_RISINGDETECT | 0x00000000 GPIO_FALLINGDETECT | 0x00000400 As result, system will start to lose interrupts from pcf8575 GPIO expander, because when OMAP GPIO IP is in smart-idle wakeup mode, there is no guarantee that transition(s) on input non wake up GPIO pin will trigger asynchronous wake-up request to PRCM and then IRQ generation. IRQ will be generated when GPIO is in active mode - for example, some time after accessing GPIO bank registers IRQs will be generated normally, but issue will happen again once PRCM will put GPIO in low power smart-idle wakeup mode. Note 1. Issue is not reproduced if debounce clk is enabled for GPIO bank. Note 2. Issue hardly reproducible if GPIO pins group contains both wakeup/non-wakeup gpios - for example, it will be hard to reproduce issue with pin2 if GPIO_IRQWAKEN_0=0x1 GPIO_IRQSTATUS_SET_0=0x3 GPIO_FALLINGDETECT = 0x3 (TRM "Power Saving by Grouping the Edge/Level Detection"). Note 3. There nothing common bitween System wake up and OMAP GPIO bank IP wake up logic - the last one defines how the GPIO bank ON-IDLE-ON transition will happen inside SoC under control of PRCM. Hence, fix the problem by removing omap_set_gpio_wakeup() function completely and so keeping always in sync GPIO IRQ mask/unmask (IRQSTATUS_SET) and wake up enable (GPIO_IRQWAKEN) bits; and adding IRQCHIP_MASK_ON_SUSPEND flag in OMAP GPIO irqchip. That way non wakeup GPIO IRQs will be properly masked/unmask by IRQ PM core during suspend/resume cycle. Cc: Roger Quadros Signed-off-by: Grygorii Strashko Acked-by: Tony Lindgren Acked-by: Santosh Shilimkar Signed-off-by: Linus Walleij --- drivers/gpio/gpio-omap.c | 42 ++-------------------------------------- 1 file changed, 2 insertions(+), 40 deletions(-) diff --git a/drivers/gpio/gpio-omap.c b/drivers/gpio/gpio-omap.c index 551dfa9d97ab..b98ede78c9d8 100644 --- a/drivers/gpio/gpio-omap.c +++ b/drivers/gpio/gpio-omap.c @@ -611,51 +611,12 @@ static inline void omap_set_gpio_irqenable(struct gpio_bank *bank, omap_disable_gpio_irqbank(bank, BIT(offset)); } -/* - * Note that ENAWAKEUP needs to be enabled in GPIO_SYSCONFIG register. - * 1510 does not seem to have a wake-up register. If JTAG is connected - * to the target, system will wake up always on GPIO events. While - * system is running all registered GPIO interrupts need to have wake-up - * enabled. When system is suspended, only selected GPIO interrupts need - * to have wake-up enabled. - */ -static int omap_set_gpio_wakeup(struct gpio_bank *bank, unsigned offset, - int enable) -{ - u32 gpio_bit = BIT(offset); - unsigned long flags; - - if (bank->non_wakeup_gpios & gpio_bit) { - dev_err(bank->chip.parent, - "Unable to modify wakeup on non-wakeup GPIO%d\n", - offset); - return -EINVAL; - } - - raw_spin_lock_irqsave(&bank->lock, flags); - if (enable) - bank->context.wake_en |= gpio_bit; - else - bank->context.wake_en &= ~gpio_bit; - - writel_relaxed(bank->context.wake_en, bank->base + bank->regs->wkup_en); - raw_spin_unlock_irqrestore(&bank->lock, flags); - - return 0; -} - /* Use disable_irq_wake() and enable_irq_wake() functions from drivers */ static int omap_gpio_wake_enable(struct irq_data *d, unsigned int enable) { struct gpio_bank *bank = omap_irq_data_get_bank(d); - unsigned offset = d->hwirq; - int ret; - ret = omap_set_gpio_wakeup(bank, offset, enable); - if (!ret) - ret = irq_set_irq_wake(bank->irq, enable); - - return ret; + return irq_set_irq_wake(bank->irq, enable); } static int omap_gpio_request(struct gpio_chip *chip, unsigned offset) @@ -1187,6 +1148,7 @@ static int omap_gpio_probe(struct platform_device *pdev) irqc->irq_bus_lock = omap_gpio_irq_bus_lock, irqc->irq_bus_sync_unlock = gpio_irq_bus_sync_unlock, irqc->name = dev_name(&pdev->dev); + irqc->flags = IRQCHIP_MASK_ON_SUSPEND; bank->irq = platform_get_irq(pdev, 0); if (bank->irq <= 0) { -- 2.39.2