diff options
| author | Julia Cartwright <julia@ni.com> | 2017-03-21 17:43:07 -0500 |
|---|---|---|
| committer | Linus Walleij <linus.walleij@linaro.org> | 2017-03-28 14:55:08 +0200 |
| commit | e1e37d6c4a78bb6fb9b67115f497337cb38de503 (patch) | |
| tree | 86ca3250c46d75dcede1cd179fa1120cd72a7029 | |
| parent | ea38ce081d155534494bac5df2bb0d343fb1679b (diff) | |
gpio: 104-idi-48: make use of raw_spinlock variants
The 104-idi-48 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>
| -rw-r--r-- | drivers/gpio/gpio-104-idi-48.c | 18 |
1 files changed, 10 insertions, 8 deletions
diff --git a/drivers/gpio/gpio-104-idi-48.c b/drivers/gpio/gpio-104-idi-48.c index 568375a7ebc2..337c048168d8 100644 --- a/drivers/gpio/gpio-104-idi-48.c +++ b/drivers/gpio/gpio-104-idi-48.c @@ -51,7 +51,7 @@ MODULE_PARM_DESC(irq, "ACCES 104-IDI-48 interrupt line numbers"); */ struct idi_48_gpio { struct gpio_chip chip; - spinlock_t lock; + raw_spinlock_t lock; spinlock_t ack_lock; unsigned char irq_mask[6]; unsigned base; @@ -112,11 +112,12 @@ static void idi_48_irq_mask(struct irq_data *data) if (!idi48gpio->irq_mask[boundary]) { idi48gpio->cos_enb &= ~BIT(boundary); - spin_lock_irqsave(&idi48gpio->lock, flags); + raw_spin_lock_irqsave(&idi48gpio->lock, flags); outb(idi48gpio->cos_enb, idi48gpio->base + 7); - spin_unlock_irqrestore(&idi48gpio->lock, flags); + raw_spin_unlock_irqrestore(&idi48gpio->lock, + flags); } return; @@ -145,11 +146,12 @@ static void idi_48_irq_unmask(struct irq_data *data) if (!prev_irq_mask) { idi48gpio->cos_enb |= BIT(boundary); - spin_lock_irqsave(&idi48gpio->lock, flags); + raw_spin_lock_irqsave(&idi48gpio->lock, flags); outb(idi48gpio->cos_enb, idi48gpio->base + 7); - spin_unlock_irqrestore(&idi48gpio->lock, flags); + raw_spin_unlock_irqrestore(&idi48gpio->lock, + flags); } return; @@ -186,11 +188,11 @@ static irqreturn_t idi_48_irq_handler(int irq, void *dev_id) spin_lock(&idi48gpio->ack_lock); - spin_lock(&idi48gpio->lock); + raw_spin_lock(&idi48gpio->lock); cos_status = inb(idi48gpio->base + 7); - spin_unlock(&idi48gpio->lock); + raw_spin_unlock(&idi48gpio->lock); /* IRQ Status (bit 6) is active low (0 = IRQ generated by device) */ if (cos_status & BIT(6)) { @@ -256,7 +258,7 @@ static int idi_48_probe(struct device *dev, unsigned int id) idi48gpio->chip.get = idi_48_gpio_get; idi48gpio->base = base[id]; - spin_lock_init(&idi48gpio->lock); + raw_spin_lock_init(&idi48gpio->lock); spin_lock_init(&idi48gpio->ack_lock); err = devm_gpiochip_add_data(dev, &idi48gpio->chip, idi48gpio); |