From: Vladimir Oltean vladimir.oltean@nxp.com
[ Upstream commit 4e50573f39229d5e9c985fa3b4923a8b29619ade ]
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 vladimir.oltean@nxp.com Link: https://lore.kernel.org/r/20191115125551.31061-1-olteanv@gmail.com Tested-by: Michael Walle michael@walle.cc Signed-off-by: Linus Walleij linus.walleij@linaro.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/gpio/gpio-mpc8xxx.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/gpio/gpio-mpc8xxx.c b/drivers/gpio/gpio-mpc8xxx.c index b863421ae7309..a031cbcdf6ef9 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;