diff options
author | Julia Cartwright <julia@ni.com> | 2017-03-21 17:43:09 -0500 |
---|---|---|
committer | Linus Walleij <linus.walleij@linaro.org> | 2017-03-28 11:13:59 +0200 |
commit | ea38ce081d155534494bac5df2bb0d343fb1679b (patch) | |
tree | e76970c32b86f621a9a2bbd53ba8369e261ca7c4 /drivers/gpio | |
parent | 3906e8089af3225a0a22c12cc3cf10be4630976e (diff) | |
download | linux-ea38ce081d155534494bac5df2bb0d343fb1679b.tar.bz2 |
gpio: pci-idio-16: make use of raw_spinlock variants
The pci-idio-16 gpio driver currently implements an irq_chip for handling
interrupts; due to how irq_chip handling is done, it's necessary for the
irq_chip methods to be invoked from hardirq context, even on a a
real-time kernel. Because the spinlock_t type becomes a "sleeping"
spinlock w/ RT kernels, it is not suitable to be used with irq_chips.
A quick audit of the operations under the lock reveal that they do only
minimal, bounded work, and are therefore safe to do under a raw spinlock.
Signed-off-by: Julia Cartwright <julia@ni.com>
Acked-by: William Breathitt Gray <vilhelm.gray@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Diffstat (limited to 'drivers/gpio')
-rw-r--r-- | drivers/gpio/gpio-pci-idio-16.c | 28 |
1 files changed, 14 insertions, 14 deletions
diff --git a/drivers/gpio/gpio-pci-idio-16.c b/drivers/gpio/gpio-pci-idio-16.c index 269ab628634b..7de4f6a2cb49 100644 --- a/drivers/gpio/gpio-pci-idio-16.c +++ b/drivers/gpio/gpio-pci-idio-16.c @@ -59,7 +59,7 @@ struct idio_16_gpio_reg { */ struct idio_16_gpio { struct gpio_chip chip; - spinlock_t lock; + raw_spinlock_t lock; struct idio_16_gpio_reg __iomem *reg; unsigned long irq_mask; }; @@ -121,7 +121,7 @@ static void idio_16_gpio_set(struct gpio_chip *chip, unsigned int offset, } else base = &idio16gpio->reg->out0_7; - spin_lock_irqsave(&idio16gpio->lock, flags); + raw_spin_lock_irqsave(&idio16gpio->lock, flags); if (value) out_state = ioread8(base) | mask; @@ -130,7 +130,7 @@ static void idio_16_gpio_set(struct gpio_chip *chip, unsigned int offset, iowrite8(out_state, base); - spin_unlock_irqrestore(&idio16gpio->lock, flags); + raw_spin_unlock_irqrestore(&idio16gpio->lock, flags); } static void idio_16_gpio_set_multiple(struct gpio_chip *chip, @@ -140,7 +140,7 @@ static void idio_16_gpio_set_multiple(struct gpio_chip *chip, unsigned long flags; unsigned int out_state; - spin_lock_irqsave(&idio16gpio->lock, flags); + raw_spin_lock_irqsave(&idio16gpio->lock, flags); /* process output lines 0-7 */ if (*mask & 0xFF) { @@ -160,7 +160,7 @@ static void idio_16_gpio_set_multiple(struct gpio_chip *chip, iowrite8(out_state, &idio16gpio->reg->out8_15); } - spin_unlock_irqrestore(&idio16gpio->lock, flags); + raw_spin_unlock_irqrestore(&idio16gpio->lock, flags); } static void idio_16_irq_ack(struct irq_data *data) @@ -177,11 +177,11 @@ static void idio_16_irq_mask(struct irq_data *data) idio16gpio->irq_mask &= ~mask; if (!idio16gpio->irq_mask) { - spin_lock_irqsave(&idio16gpio->lock, flags); + raw_spin_lock_irqsave(&idio16gpio->lock, flags); iowrite8(0, &idio16gpio->reg->irq_ctl); - spin_unlock_irqrestore(&idio16gpio->lock, flags); + raw_spin_unlock_irqrestore(&idio16gpio->lock, flags); } } @@ -196,11 +196,11 @@ static void idio_16_irq_unmask(struct irq_data *data) idio16gpio->irq_mask |= mask; if (!prev_irq_mask) { - spin_lock_irqsave(&idio16gpio->lock, flags); + raw_spin_lock_irqsave(&idio16gpio->lock, flags); ioread8(&idio16gpio->reg->irq_ctl); - spin_unlock_irqrestore(&idio16gpio->lock, flags); + raw_spin_unlock_irqrestore(&idio16gpio->lock, flags); } } @@ -229,11 +229,11 @@ static irqreturn_t idio_16_irq_handler(int irq, void *dev_id) struct gpio_chip *const chip = &idio16gpio->chip; int gpio; - spin_lock(&idio16gpio->lock); + raw_spin_lock(&idio16gpio->lock); irq_status = ioread8(&idio16gpio->reg->irq_status); - spin_unlock(&idio16gpio->lock); + raw_spin_unlock(&idio16gpio->lock); /* Make sure our device generated IRQ */ if (!(irq_status & 0x3) || !(irq_status & 0x4)) @@ -242,12 +242,12 @@ static irqreturn_t idio_16_irq_handler(int irq, void *dev_id) for_each_set_bit(gpio, &idio16gpio->irq_mask, chip->ngpio) generic_handle_irq(irq_find_mapping(chip->irqdomain, gpio)); - spin_lock(&idio16gpio->lock); + raw_spin_lock(&idio16gpio->lock); /* Clear interrupt */ iowrite8(0, &idio16gpio->reg->in0_7); - spin_unlock(&idio16gpio->lock); + raw_spin_unlock(&idio16gpio->lock); return IRQ_HANDLED; } @@ -302,7 +302,7 @@ static int idio_16_probe(struct pci_dev *pdev, const struct pci_device_id *id) idio16gpio->chip.set = idio_16_gpio_set; idio16gpio->chip.set_multiple = idio_16_gpio_set_multiple; - spin_lock_init(&idio16gpio->lock); + raw_spin_lock_init(&idio16gpio->lock); err = devm_gpiochip_add_data(dev, &idio16gpio->chip, idio16gpio); if (err) { |