[PATCH] gpio: ml-ioh: use raw_spinlock_t for the register lock
From: Junjie Cao
Date: Thu Jul 30 2026 - 23:34:27 EST
ioh_irq_type() is registered as the irq_chip .irq_set_type callback and
takes chip->spinlock with spin_lock_irqsave(). This callback is reached
from __setup_irq() -> __irq_set_trigger() -> chip->irq_set_type() while
the caller holds desc->lock, a raw_spinlock_t, with hardirqs disabled.
That context is not sleepable, but on PREEMPT_RT a regular spinlock_t is
an rtmutex-backed sleeping lock, so acquiring it there is invalid.
ioh_irq_enable() and ioh_irq_disable() take the same lock from the
.irq_enable/.irq_disable callbacks, which are likewise invoked with
desc->lock held.
Convert the register lock to raw_spinlock_t. The same lock also
serializes the GPIO direction/value callbacks and the suspend/resume
register save/restore, and those critical sections only perform short
sequences of MMIO register accesses (ioread32()/iowrite32()); the
.irq_set_type callback additionally emits a dev_warn() on an unsupported
type. None of these are sleepable operations, so keeping this register
lock non-sleeping is appropriate for the irqchip callbacks and does not
change the GPIO-side locking contract.
This is the same fix as commit a02b8950d619 ("gpio: pch: use
raw_spinlock_t for the register lock"); this driver shares the same
structure as gpio-pch.
Fixes: 54be566317b6 ("gpio-ml-ioh: Support interrupt function")
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Junjie Cao <junjie.cao@xxxxxxxxx>
---
drivers/gpio/gpio-ml-ioh.c | 36 ++++++++++++++++++------------------
1 file changed, 18 insertions(+), 18 deletions(-)
diff --git a/drivers/gpio/gpio-ml-ioh.c b/drivers/gpio/gpio-ml-ioh.c
index 6576e5dcb0ee..0a9d34b7636e 100644
--- a/drivers/gpio/gpio-ml-ioh.c
+++ b/drivers/gpio/gpio-ml-ioh.c
@@ -84,7 +84,7 @@ struct ioh_gpio {
u32 gpio_use_sel;
int ch;
int irq_base;
- spinlock_t spinlock;
+ raw_spinlock_t spinlock;
};
static const int num_ports[] = {6, 12, 16, 16, 15, 16, 16, 12};
@@ -95,7 +95,7 @@ static int ioh_gpio_set(struct gpio_chip *gpio, unsigned int nr, int val)
struct ioh_gpio *chip = gpiochip_get_data(gpio);
unsigned long flags;
- spin_lock_irqsave(&chip->spinlock, flags);
+ raw_spin_lock_irqsave(&chip->spinlock, flags);
reg_val = ioread32(&chip->reg->regs[chip->ch].po);
if (val)
reg_val |= BIT(nr);
@@ -103,7 +103,7 @@ static int ioh_gpio_set(struct gpio_chip *gpio, unsigned int nr, int val)
reg_val &= ~BIT(nr);
iowrite32(reg_val, &chip->reg->regs[chip->ch].po);
- spin_unlock_irqrestore(&chip->spinlock, flags);
+ raw_spin_unlock_irqrestore(&chip->spinlock, flags);
return 0;
}
@@ -123,7 +123,7 @@ static int ioh_gpio_direction_output(struct gpio_chip *gpio, unsigned nr,
u32 reg_val;
unsigned long flags;
- spin_lock_irqsave(&chip->spinlock, flags);
+ raw_spin_lock_irqsave(&chip->spinlock, flags);
pm = ioread32(&chip->reg->regs[chip->ch].pm);
pm &= BIT(num_ports[chip->ch]) - 1;
pm |= BIT(nr);
@@ -136,7 +136,7 @@ static int ioh_gpio_direction_output(struct gpio_chip *gpio, unsigned nr,
reg_val &= ~BIT(nr);
iowrite32(reg_val, &chip->reg->regs[chip->ch].po);
- spin_unlock_irqrestore(&chip->spinlock, flags);
+ raw_spin_unlock_irqrestore(&chip->spinlock, flags);
return 0;
}
@@ -147,12 +147,12 @@ static int ioh_gpio_direction_input(struct gpio_chip *gpio, unsigned nr)
u32 pm;
unsigned long flags;
- spin_lock_irqsave(&chip->spinlock, flags);
+ raw_spin_lock_irqsave(&chip->spinlock, flags);
pm = ioread32(&chip->reg->regs[chip->ch].pm);
pm &= BIT(num_ports[chip->ch]) - 1;
pm &= ~BIT(nr);
iowrite32(pm, &chip->reg->regs[chip->ch].pm);
- spin_unlock_irqrestore(&chip->spinlock, flags);
+ raw_spin_unlock_irqrestore(&chip->spinlock, flags);
return 0;
}
@@ -256,7 +256,7 @@ static int ioh_irq_type(struct irq_data *d, unsigned int type)
dev_dbg(chip->dev, "%s:irq=%d type=%d ch=%d pos=%d type=%d\n",
__func__, irq, type, ch, im_pos, type);
- spin_lock_irqsave(&chip->spinlock, flags);
+ raw_spin_lock_irqsave(&chip->spinlock, flags);
switch (type) {
case IRQ_TYPE_EDGE_RISING:
@@ -296,7 +296,7 @@ static int ioh_irq_type(struct irq_data *d, unsigned int type)
ien = ioread32(&chip->reg->regs[chip->ch].ien);
iowrite32(ien | BIT(ch), &chip->reg->regs[chip->ch].ien);
end:
- spin_unlock_irqrestore(&chip->spinlock, flags);
+ raw_spin_unlock_irqrestore(&chip->spinlock, flags);
return 0;
}
@@ -326,11 +326,11 @@ static void ioh_irq_disable(struct irq_data *d)
unsigned long flags;
u32 ien;
- spin_lock_irqsave(&chip->spinlock, flags);
+ raw_spin_lock_irqsave(&chip->spinlock, flags);
ien = ioread32(&chip->reg->regs[chip->ch].ien);
ien &= ~BIT(d->irq - chip->irq_base);
iowrite32(ien, &chip->reg->regs[chip->ch].ien);
- spin_unlock_irqrestore(&chip->spinlock, flags);
+ raw_spin_unlock_irqrestore(&chip->spinlock, flags);
}
static void ioh_irq_enable(struct irq_data *d)
@@ -340,11 +340,11 @@ static void ioh_irq_enable(struct irq_data *d)
unsigned long flags;
u32 ien;
- spin_lock_irqsave(&chip->spinlock, flags);
+ raw_spin_lock_irqsave(&chip->spinlock, flags);
ien = ioread32(&chip->reg->regs[chip->ch].ien);
ien |= BIT(d->irq - chip->irq_base);
iowrite32(ien, &chip->reg->regs[chip->ch].ien);
- spin_unlock_irqrestore(&chip->spinlock, flags);
+ raw_spin_unlock_irqrestore(&chip->spinlock, flags);
}
static irqreturn_t ioh_gpio_handler(int irq, void *dev_id)
@@ -440,7 +440,7 @@ static int ioh_gpio_probe(struct pci_dev *pdev,
chip->base = base;
chip->reg = chip->base;
chip->ch = i;
- spin_lock_init(&chip->spinlock);
+ raw_spin_lock_init(&chip->spinlock);
ioh_gpio_setup(chip, num_ports[i]);
ret = devm_gpiochip_add_data(dev, &chip->gpio, chip);
if (ret) {
@@ -484,9 +484,9 @@ static int ioh_gpio_suspend(struct device *dev)
struct ioh_gpio *chip = dev_get_drvdata(dev);
unsigned long flags;
- spin_lock_irqsave(&chip->spinlock, flags);
+ raw_spin_lock_irqsave(&chip->spinlock, flags);
ioh_gpio_save_reg_conf(chip);
- spin_unlock_irqrestore(&chip->spinlock, flags);
+ raw_spin_unlock_irqrestore(&chip->spinlock, flags);
return 0;
}
@@ -496,11 +496,11 @@ static int ioh_gpio_resume(struct device *dev)
struct ioh_gpio *chip = dev_get_drvdata(dev);
unsigned long flags;
- spin_lock_irqsave(&chip->spinlock, flags);
+ raw_spin_lock_irqsave(&chip->spinlock, flags);
iowrite32(0x01, &chip->reg->srst);
iowrite32(0x00, &chip->reg->srst);
ioh_gpio_restore_reg_conf(chip);
- spin_unlock_irqrestore(&chip->spinlock, flags);
+ raw_spin_unlock_irqrestore(&chip->spinlock, flags);
return 0;
}
base-commit: a02b8950d619123da64f69b70fe1dadef217dfe4
--
2.43.0