[PATCH 18/19] pinctrl: sirf: atlas7: make use of raw_spinlock variants

From: Julia Cartwright
Date: Thu Mar 09 2017 - 12:07:06 EST


The sirf atlas7 pinctrl drivers currently implement 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@xxxxxx>
---
drivers/pinctrl/sirf/pinctrl-atlas7.c | 44 +++++++++++++++++------------------
1 file changed, 22 insertions(+), 22 deletions(-)

diff --git a/drivers/pinctrl/sirf/pinctrl-atlas7.c b/drivers/pinctrl/sirf/pinctrl-atlas7.c
index 600d6427a978..1efa315a7dbe 100644
--- a/drivers/pinctrl/sirf/pinctrl-atlas7.c
+++ b/drivers/pinctrl/sirf/pinctrl-atlas7.c
@@ -352,7 +352,7 @@ struct atlas7_gpio_chip {
void __iomem *reg;
struct clk *clk;
int nbank;
- spinlock_t lock;
+ raw_spinlock_t lock;
struct gpio_chip chip;
struct atlas7_gpio_bank banks[0];
};
@@ -5650,13 +5650,13 @@ static void atlas7_gpio_irq_ack(struct irq_data *d)
pin_in_bank = d->hwirq - bank->gpio_offset;
ctrl_reg = ATLAS7_GPIO_CTRL(bank, pin_in_bank);

- spin_lock_irqsave(&a7gc->lock, flags);
+ raw_spin_lock_irqsave(&a7gc->lock, flags);

val = readl(ctrl_reg);
/* clear interrupt status */
writel(val, ctrl_reg);

- spin_unlock_irqrestore(&a7gc->lock, flags);
+ raw_spin_unlock_irqrestore(&a7gc->lock, flags);
}

static void __atlas7_gpio_irq_mask(struct atlas7_gpio_chip *a7gc, int idx)
@@ -5681,11 +5681,11 @@ static void atlas7_gpio_irq_mask(struct irq_data *d)
struct atlas7_gpio_chip *a7gc = gpiochip_get_data(gc);
unsigned long flags;

- spin_lock_irqsave(&a7gc->lock, flags);
+ raw_spin_lock_irqsave(&a7gc->lock, flags);

__atlas7_gpio_irq_mask(a7gc, d->hwirq);

- spin_unlock_irqrestore(&a7gc->lock, flags);
+ raw_spin_unlock_irqrestore(&a7gc->lock, flags);
}

static void atlas7_gpio_irq_unmask(struct irq_data *d)
@@ -5701,14 +5701,14 @@ static void atlas7_gpio_irq_unmask(struct irq_data *d)
pin_in_bank = d->hwirq - bank->gpio_offset;
ctrl_reg = ATLAS7_GPIO_CTRL(bank, pin_in_bank);

- spin_lock_irqsave(&a7gc->lock, flags);
+ raw_spin_lock_irqsave(&a7gc->lock, flags);

val = readl(ctrl_reg);
val &= ~ATLAS7_GPIO_CTL_INTR_STATUS_MASK;
val |= ATLAS7_GPIO_CTL_INTR_EN_MASK;
writel(val, ctrl_reg);

- spin_unlock_irqrestore(&a7gc->lock, flags);
+ raw_spin_unlock_irqrestore(&a7gc->lock, flags);
}

static int atlas7_gpio_irq_type(struct irq_data *d,
@@ -5725,7 +5725,7 @@ static int atlas7_gpio_irq_type(struct irq_data *d,
pin_in_bank = d->hwirq - bank->gpio_offset;
ctrl_reg = ATLAS7_GPIO_CTRL(bank, pin_in_bank);

- spin_lock_irqsave(&a7gc->lock, flags);
+ raw_spin_lock_irqsave(&a7gc->lock, flags);

val = readl(ctrl_reg);
val &= ~(ATLAS7_GPIO_CTL_INTR_STATUS_MASK |
@@ -5768,7 +5768,7 @@ static int atlas7_gpio_irq_type(struct irq_data *d,

writel(val, ctrl_reg);

- spin_unlock_irqrestore(&a7gc->lock, flags);
+ raw_spin_unlock_irqrestore(&a7gc->lock, flags);

return 0;
}
@@ -5863,7 +5863,7 @@ static int atlas7_gpio_request(struct gpio_chip *chip,
if (pinctrl_request_gpio(chip->base + gpio))
return -ENODEV;

- spin_lock_irqsave(&a7gc->lock, flags);
+ raw_spin_lock_irqsave(&a7gc->lock, flags);

/*
* default status:
@@ -5872,7 +5872,7 @@ static int atlas7_gpio_request(struct gpio_chip *chip,
__atlas7_gpio_set_input(a7gc, gpio);
__atlas7_gpio_irq_mask(a7gc, gpio);

- spin_unlock_irqrestore(&a7gc->lock, flags);
+ raw_spin_unlock_irqrestore(&a7gc->lock, flags);

return 0;
}
@@ -5883,12 +5883,12 @@ static void atlas7_gpio_free(struct gpio_chip *chip,
struct atlas7_gpio_chip *a7gc = gpiochip_get_data(chip);
unsigned long flags;

- spin_lock_irqsave(&a7gc->lock, flags);
+ raw_spin_lock_irqsave(&a7gc->lock, flags);

__atlas7_gpio_irq_mask(a7gc, gpio);
__atlas7_gpio_set_input(a7gc, gpio);

- spin_unlock_irqrestore(&a7gc->lock, flags);
+ raw_spin_unlock_irqrestore(&a7gc->lock, flags);

pinctrl_free_gpio(chip->base + gpio);
}
@@ -5899,11 +5899,11 @@ static int atlas7_gpio_direction_input(struct gpio_chip *chip,
struct atlas7_gpio_chip *a7gc = gpiochip_get_data(chip);
unsigned long flags;

- spin_lock_irqsave(&a7gc->lock, flags);
+ raw_spin_lock_irqsave(&a7gc->lock, flags);

__atlas7_gpio_set_input(a7gc, gpio);

- spin_unlock_irqrestore(&a7gc->lock, flags);
+ raw_spin_unlock_irqrestore(&a7gc->lock, flags);

return 0;
}
@@ -5936,11 +5936,11 @@ static int atlas7_gpio_direction_output(struct gpio_chip *chip,
struct atlas7_gpio_chip *a7gc = gpiochip_get_data(chip);
unsigned long flags;

- spin_lock_irqsave(&a7gc->lock, flags);
+ raw_spin_lock_irqsave(&a7gc->lock, flags);

__atlas7_gpio_set_output(a7gc, gpio, value);

- spin_unlock_irqrestore(&a7gc->lock, flags);
+ raw_spin_unlock_irqrestore(&a7gc->lock, flags);

return 0;
}
@@ -5956,11 +5956,11 @@ static int atlas7_gpio_get_value(struct gpio_chip *chip,
bank = atlas7_gpio_to_bank(a7gc, gpio);
pin_in_bank = gpio - bank->gpio_offset;

- spin_lock_irqsave(&a7gc->lock, flags);
+ raw_spin_lock_irqsave(&a7gc->lock, flags);

val = readl(ATLAS7_GPIO_CTRL(bank, pin_in_bank));

- spin_unlock_irqrestore(&a7gc->lock, flags);
+ raw_spin_unlock_irqrestore(&a7gc->lock, flags);

return !!(val & ATLAS7_GPIO_CTL_DATAIN_MASK);
}
@@ -5978,7 +5978,7 @@ static void atlas7_gpio_set_value(struct gpio_chip *chip,
pin_in_bank = gpio - bank->gpio_offset;
ctrl_reg = ATLAS7_GPIO_CTRL(bank, pin_in_bank);

- spin_lock_irqsave(&a7gc->lock, flags);
+ raw_spin_lock_irqsave(&a7gc->lock, flags);

ctrl = readl(ctrl_reg);
if (value)
@@ -5987,7 +5987,7 @@ static void atlas7_gpio_set_value(struct gpio_chip *chip,
ctrl &= ~ATLAS7_GPIO_CTL_DATAOUT_MASK;
writel(ctrl, ctrl_reg);

- spin_unlock_irqrestore(&a7gc->lock, flags);
+ raw_spin_unlock_irqrestore(&a7gc->lock, flags);
}

static const struct of_device_id atlas7_gpio_ids[] = {
@@ -6036,7 +6036,7 @@ static int atlas7_gpio_probe(struct platform_device *pdev)
}

a7gc->nbank = nbank;
- spin_lock_init(&a7gc->lock);
+ raw_spin_lock_init(&a7gc->lock);

/* Setup GPIO Chip */
chip = &a7gc->chip;
--
2.11.1