From 4e50573f39229d5e9c985fa3b4923a8b29619ade Mon Sep 17 00:00:00 2001 From: Vladimir Oltean Date: Fri, 15 Nov 2019 14:55:51 +0200 Subject: gpio: mpc8xxx: Don't overwrite default irq_set_type callback The per-SoC devtype structures can contain their own callbacks that overwrite mpc8xxx_gpio_devtype_default. The clear intention is that mpc8xxx_irq_set_type is used in case the SoC does not specify a more specific callback. But what happens is that if the SoC doesn't specify one, its .irq_set_type is de-facto NULL, and this overwrites mpc8xxx_irq_set_type to a no-op. This means that the following SoCs are affected: - fsl,mpc8572-gpio - fsl,ls1028a-gpio - fsl,ls1088a-gpio On these boards, the irq_set_type does exactly nothing, and the GPIO controller keeps its GPICR register in the hardware-default state. On the LS1028A, that is ACTIVE_BOTH, which means 2 interrupts are raised even if the IRQ client requests LEVEL_HIGH. Another implication is that the IRQs are not checked (e.g. level-triggered interrupts are not rejected, although they are not supported). Fixes: 82e39b0d8566 ("gpio: mpc8xxx: handle differences between incarnations at a single place") Signed-off-by: Vladimir Oltean Link: https://lore.kernel.org/r/20191115125551.31061-1-olteanv@gmail.com Tested-by: Michael Walle Signed-off-by: Linus Walleij --- drivers/gpio/gpio-mpc8xxx.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'drivers/gpio/gpio-mpc8xxx.c') diff --git a/drivers/gpio/gpio-mpc8xxx.c b/drivers/gpio/gpio-mpc8xxx.c index 58ff37219fce..81f0f31e04d9 100644 --- a/drivers/gpio/gpio-mpc8xxx.c +++ b/drivers/gpio/gpio-mpc8xxx.c @@ -377,7 +377,8 @@ static int mpc8xxx_probe(struct platform_device *pdev) * It's assumed that only a single type of gpio controller is available * on the current machine, so overwriting global data is fine. */ - mpc8xxx_irq_chip.irq_set_type = devtype->irq_set_type; + if (devtype->irq_set_type) + mpc8xxx_irq_chip.irq_set_type = devtype->irq_set_type; if (devtype->gpio_dir_out) gc->direction_output = devtype->gpio_dir_out; -- cgit v1.2.3