Re: [PATCH] pinctrl: apple: Always return valid type in apple_gpio_irq_type

From: Joey Gouly
Date: Mon Nov 01 2021 - 11:18:56 EST


Hi Sven,

On Mon, Nov 01, 2021 at 04:06:40PM +0100, Sven Peter wrote:
> apple_gpio_irq_type can possibly return -EINVAL which triggers the
> following compile error with gcc 9 because the type no longer fits
> into the mask.
>
> drivers/pinctrl/pinctrl-apple-gpio.c: In function 'apple_gpio_irq_set_type':
> ././include/linux/compiler_types.h:335:38: error: call to '__compiletime_assert_289' declared with attribute error: FIELD_PREP: value too large for the field
> 335 | _compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__)
> | ^
> [...]
> drivers/pinctrl/pinctrl-apple-gpio.c:294:7: note: in expansion of macro 'FIELD_PREP'
> 294 | FIELD_PREP(REG_GPIOx_MODE, irqtype));
> | ^~~~~~~~~~
>
> Fix this by making the return value always valid and instead checking
> for REG_GPIOx_IN_IRQ_OFF in apple_gpio_irq_set_type and return -EINVAL
> from there.
>
> Fixes: a0f160ffcb83 ("pinctrl: add pinctrl/GPIO driver for Apple SoCs")
> Signed-off-by: Sven Peter <sven@xxxxxxxxxxxxx>
> ---
> drivers/pinctrl/pinctrl-apple-gpio.c | 12 ++++++------
> 1 file changed, 6 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/pinctrl/pinctrl-apple-gpio.c b/drivers/pinctrl/pinctrl-apple-gpio.c
> index 0cc346bfc4c3..a7861079a650 100644
> --- a/drivers/pinctrl/pinctrl-apple-gpio.c
> +++ b/drivers/pinctrl/pinctrl-apple-gpio.c
> @@ -258,7 +258,7 @@ static void apple_gpio_irq_ack(struct irq_data *data)
> pctl->base + REG_IRQ(irqgrp, data->hwirq));
> }
>
> -static int apple_gpio_irq_type(unsigned int type)
> +static unsigned int apple_gpio_irq_type(unsigned int type)
> {
> switch (type & IRQ_TYPE_SENSE_MASK) {
> case IRQ_TYPE_EDGE_RISING:
> @@ -272,7 +272,7 @@ static int apple_gpio_irq_type(unsigned int type)
> case IRQ_TYPE_LEVEL_LOW:
> return REG_GPIOx_IN_IRQ_LO;
> default:
> - return -EINVAL;
> + return REG_GPIOx_IN_IRQ_OFF;
> }
> }
>
> @@ -288,7 +288,7 @@ static void apple_gpio_irq_unmask(struct irq_data *data)
> {
> struct apple_gpio_pinctrl *pctl =
> gpiochip_get_data(irq_data_get_irq_chip_data(data));
> - int irqtype = apple_gpio_irq_type(irqd_get_trigger_type(data));
> + unsigned int irqtype = apple_gpio_irq_type(irqd_get_trigger_type(data));
>
> apple_gpio_set_reg(pctl, data->hwirq, REG_GPIOx_MODE,
> FIELD_PREP(REG_GPIOx_MODE, irqtype));
> @@ -313,10 +313,10 @@ static int apple_gpio_irq_set_type(struct irq_data *data,
> {
> struct apple_gpio_pinctrl *pctl =
> gpiochip_get_data(irq_data_get_irq_chip_data(data));
> - int irqtype = apple_gpio_irq_type(type);
> + unsigned int irqtype = apple_gpio_irq_type(type);
>
> - if (irqtype < 0)
> - return irqtype;
> + if (irqtype == REG_GPIOx_IN_IRQ_OFF)
> + return -EINVAL;
>
> apple_gpio_set_reg(pctl, data->hwirq, REG_GPIOx_MODE,
> FIELD_PREP(REG_GPIOx_MODE, irqtype));
> --
> 2.25.1
>

This was previously reported, but was miscategorised it as a compiler bug, so thanks for fixing this!

Reviewed-by: Joey Gouly <joey.gouly@xxxxxxx>

Thanks,
Joey