diff options
| author | Julia Cartwright <julia@ni.com> | 2017-03-09 10:21:49 -0600 |
|---|---|---|
| committer | Linus Walleij <linus.walleij@linaro.org> | 2017-03-16 21:52:06 +0100 |
| commit | 21d01c9c081ab231d6ef9d94ad9345c58b6568c1 (patch) | |
| tree | d440b4fc169af796d9ed8fd171aa7b2c70a69499 /drivers/gpio/gpio-altera.c | |
| parent | 660549e05d6bf7ed7160de51da2948c2f1646f7e (diff) | |
| download | linux-21d01c9c081ab231d6ef9d94ad9345c58b6568c1.tar.gz | |
gpio: altera: make use of raw_spinlock variants
The altera 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> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Diffstat (limited to 'drivers/gpio/gpio-altera.c')
| -rw-r--r-- | drivers/gpio/gpio-altera.c | 24 |
1 files changed, 12 insertions, 12 deletions
diff --git a/drivers/gpio/gpio-altera.c b/drivers/gpio/gpio-altera.c index 5bddbd507ca9..6c08d16ea911 100644 --- a/drivers/gpio/gpio-altera.c +++ b/drivers/gpio/gpio-altera.c @@ -38,7 +38,7 @@ */ struct altera_gpio_chip { struct of_mm_gpio_chip mmchip; - spinlock_t gpio_lock; + raw_spinlock_t gpio_lock; int interrupt_trigger; int mapped_irq; }; @@ -53,12 +53,12 @@ static void altera_gpio_irq_unmask(struct irq_data *d) altera_gc = gpiochip_get_data(irq_data_get_irq_chip_data(d)); mm_gc = &altera_gc->mmchip; - spin_lock_irqsave(&altera_gc->gpio_lock, flags); + raw_spin_lock_irqsave(&altera_gc->gpio_lock, flags); intmask = readl(mm_gc->regs + ALTERA_GPIO_IRQ_MASK); /* Set ALTERA_GPIO_IRQ_MASK bit to unmask */ intmask |= BIT(irqd_to_hwirq(d)); writel(intmask, mm_gc->regs + ALTERA_GPIO_IRQ_MASK); - spin_unlock_irqrestore(&altera_gc->gpio_lock, flags); + raw_spin_unlock_irqrestore(&altera_gc->gpio_lock, flags); } static void altera_gpio_irq_mask(struct irq_data *d) @@ -71,12 +71,12 @@ static void altera_gpio_irq_mask(struct irq_data *d) altera_gc = gpiochip_get_data(irq_data_get_irq_chip_data(d)); mm_gc = &altera_gc->mmchip; - spin_lock_irqsave(&altera_gc->gpio_lock, flags); + raw_spin_lock_irqsave(&altera_gc->gpio_lock, flags); intmask = readl(mm_gc->regs + ALTERA_GPIO_IRQ_MASK); /* Clear ALTERA_GPIO_IRQ_MASK bit to mask */ intmask &= ~BIT(irqd_to_hwirq(d)); writel(intmask, mm_gc->regs + ALTERA_GPIO_IRQ_MASK); - spin_unlock_irqrestore(&altera_gc->gpio_lock, flags); + raw_spin_unlock_irqrestore(&altera_gc->gpio_lock, flags); } /** @@ -143,14 +143,14 @@ static void altera_gpio_set(struct gpio_chip *gc, unsigned offset, int value) mm_gc = to_of_mm_gpio_chip(gc); chip = gpiochip_get_data(gc); - spin_lock_irqsave(&chip->gpio_lock, flags); + raw_spin_lock_irqsave(&chip->gpio_lock, flags); data_reg = readl(mm_gc->regs + ALTERA_GPIO_DATA); if (value) data_reg |= BIT(offset); else data_reg &= ~BIT(offset); writel(data_reg, mm_gc->regs + ALTERA_GPIO_DATA); - spin_unlock_irqrestore(&chip->gpio_lock, flags); + raw_spin_unlock_irqrestore(&chip->gpio_lock, flags); } static int altera_gpio_direction_input(struct gpio_chip *gc, unsigned offset) @@ -163,12 +163,12 @@ static int altera_gpio_direction_input(struct gpio_chip *gc, unsigned offset) mm_gc = to_of_mm_gpio_chip(gc); chip = gpiochip_get_data(gc); - spin_lock_irqsave(&chip->gpio_lock, flags); + raw_spin_lock_irqsave(&chip->gpio_lock, flags); /* Set pin as input, assumes software controlled IP */ gpio_ddr = readl(mm_gc->regs + ALTERA_GPIO_DIR); gpio_ddr &= ~BIT(offset); writel(gpio_ddr, mm_gc->regs + ALTERA_GPIO_DIR); - spin_unlock_irqrestore(&chip->gpio_lock, flags); + raw_spin_unlock_irqrestore(&chip->gpio_lock, flags); return 0; } @@ -184,7 +184,7 @@ static int altera_gpio_direction_output(struct gpio_chip *gc, mm_gc = to_of_mm_gpio_chip(gc); chip = gpiochip_get_data(gc); - spin_lock_irqsave(&chip->gpio_lock, flags); + raw_spin_lock_irqsave(&chip->gpio_lock, flags); /* Sets the GPIO value */ data_reg = readl(mm_gc->regs + ALTERA_GPIO_DATA); if (value) @@ -197,7 +197,7 @@ static int altera_gpio_direction_output(struct gpio_chip *gc, gpio_ddr = readl(mm_gc->regs + ALTERA_GPIO_DIR); gpio_ddr |= BIT(offset); writel(gpio_ddr, mm_gc->regs + ALTERA_GPIO_DIR); - spin_unlock_irqrestore(&chip->gpio_lock, flags); + raw_spin_unlock_irqrestore(&chip->gpio_lock, flags); return 0; } @@ -266,7 +266,7 @@ static int altera_gpio_probe(struct platform_device *pdev) if (!altera_gc) return -ENOMEM; - spin_lock_init(&altera_gc->gpio_lock); + raw_spin_lock_init(&altera_gc->gpio_lock); if (of_property_read_u32(node, "altr,ngpio", ®)) /* By default assume maximum ngpio */ |