The Intel Lynxpoint pinctrl driver implements irqchip callbacks which are called with desc->lock raw_spinlock held. In mainline this is fine because spinlock resolves to raw_spinlock. However, running the same code in -rt we will get a BUG() asserted. This is because in -rt spinlocks are preemptible so taking the driver private spinlock in irqchip callbacks causes might_sleep() to trigger. In order to keep -rt happy but at the same time make sure that register accesses get serialized, convert the driver to use raw_spinlock instead. Signed-off-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx> --- drivers/pinctrl/intel/pinctrl-lynxpoint.c | 28 +++++++++++------------ 1 file changed, 14 insertions(+), 14 deletions(-) diff --git a/drivers/pinctrl/intel/pinctrl-lynxpoint.c b/drivers/pinctrl/intel/pinctrl-lynxpoint.c index e9e47c0d5be7..6467095523cc 100644 --- a/drivers/pinctrl/intel/pinctrl-lynxpoint.c +++ b/drivers/pinctrl/intel/pinctrl-lynxpoint.c @@ -47,7 +47,7 @@ struct lp_gpio { struct gpio_chip chip; struct platform_device *pdev; - spinlock_t lock; + raw_spinlock_t lock; unsigned long reg_base; }; @@ -144,7 +144,7 @@ static int lp_irq_type(struct irq_data *d, unsigned type) if (hwirq >= lg->chip.ngpio) return -EINVAL; - spin_lock_irqsave(&lg->lock, flags); + raw_spin_lock_irqsave(&lg->lock, flags); value = inl(reg); /* set both TRIG_SEL and INV bits to 0 for rising edge */ @@ -164,7 +164,7 @@ static int lp_irq_type(struct irq_data *d, unsigned type) value |= TRIG_SEL_BIT | INT_INV_BIT; outl(value, reg); - spin_unlock_irqrestore(&lg->lock, flags); + raw_spin_unlock_irqrestore(&lg->lock, flags); return 0; } @@ -181,14 +181,14 @@ static void lp_gpio_set(struct gpio_chip *chip, unsigned offset, int value) unsigned long reg = lp_gpio_reg(chip, offset, LP_CONFIG1); unsigned long flags; - spin_lock_irqsave(&lg->lock, flags); + raw_spin_lock_irqsave(&lg->lock, flags); if (value) outl(inl(reg) | OUT_LVL_BIT, reg); else outl(inl(reg) & ~OUT_LVL_BIT, reg); - spin_unlock_irqrestore(&lg->lock, flags); + raw_spin_unlock_irqrestore(&lg->lock, flags); } static int lp_gpio_direction_input(struct gpio_chip *chip, unsigned offset) @@ -197,9 +197,9 @@ static int lp_gpio_direction_input(struct gpio_chip *chip, unsigned offset) unsigned long reg = lp_gpio_reg(chip, offset, LP_CONFIG1); unsigned long flags; - spin_lock_irqsave(&lg->lock, flags); + raw_spin_lock_irqsave(&lg->lock, flags); outl(inl(reg) | DIR_BIT, reg); - spin_unlock_irqrestore(&lg->lock, flags); + raw_spin_unlock_irqrestore(&lg->lock, flags); return 0; } @@ -213,9 +213,9 @@ static int lp_gpio_direction_output(struct gpio_chip *chip, lp_gpio_set(chip, offset, value); - spin_lock_irqsave(&lg->lock, flags); + raw_spin_lock_irqsave(&lg->lock, flags); outl(inl(reg) & ~DIR_BIT, reg); - spin_unlock_irqrestore(&lg->lock, flags); + raw_spin_unlock_irqrestore(&lg->lock, flags); return 0; } @@ -266,9 +266,9 @@ static void lp_irq_enable(struct irq_data *d) unsigned long reg = lp_gpio_reg(&lg->chip, hwirq, LP_INT_ENABLE); unsigned long flags; - spin_lock_irqsave(&lg->lock, flags); + raw_spin_lock_irqsave(&lg->lock, flags); outl(inl(reg) | BIT(hwirq % 32), reg); - spin_unlock_irqrestore(&lg->lock, flags); + raw_spin_unlock_irqrestore(&lg->lock, flags); } static void lp_irq_disable(struct irq_data *d) @@ -279,9 +279,9 @@ static void lp_irq_disable(struct irq_data *d) unsigned long reg = lp_gpio_reg(&lg->chip, hwirq, LP_INT_ENABLE); unsigned long flags; - spin_lock_irqsave(&lg->lock, flags); + raw_spin_lock_irqsave(&lg->lock, flags); outl(inl(reg) & ~BIT(hwirq % 32), reg); - spin_unlock_irqrestore(&lg->lock, flags); + raw_spin_unlock_irqrestore(&lg->lock, flags); } static struct irq_chip lp_irqchip = { @@ -345,7 +345,7 @@ static int lp_gpio_probe(struct platform_device *pdev) return -EBUSY; } - spin_lock_init(&lg->lock); + raw_spin_lock_init(&lg->lock); gc = &lg->chip; gc->label = dev_name(dev); -- 2.24.0.rc1