mfd: asic3: Make use of raw_spinlock variants

The asic3 mfd 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: Lee Jones <lee.jones@linaro.org>

1 files changed, 28 insertions, 28 deletions

diff --git a/drivers/mfd/asic3.c b/drivers/mfd/asic3.c
index 0413c8159551..cf2e25ab2940 100644
--- a/drivers/mfd/asic3.c
+++ b/drivers/mfd/asic3.c
@@ -78,7 +78,7 @@ struct asic3 {
         unsigned int bus_shift;
         unsigned int irq_nr;
         unsigned int irq_base;
-        spinlock_t lock;
+        raw_spinlock_t lock;
         u16 irq_bothedge[4];
         struct gpio_chip gpio;
         struct device *dev;
@@ -108,14 +108,14 @@ static void asic3_set_register(struct asic3 *asic, u32 reg, u32 bits, bool set)
         unsigned long flags;
         u32 val;
 
-        spin_lock_irqsave(&asic->lock, flags);
+        raw_spin_lock_irqsave(&asic->lock, flags);
         val = asic3_read_register(asic, reg);
         if (set)
                 val |= bits;
         else
                 val &= ~bits;
         asic3_write_register(asic, reg, val);
-        spin_unlock_irqrestore(&asic->lock, flags);
+        raw_spin_unlock_irqrestore(&asic->lock, flags);
 }
 
 /* IRQs */
@@ -129,13 +129,13 @@ static void asic3_irq_flip_edge(struct asic3 *asic,
         u16 edge;
         unsigned long flags;
 
-        spin_lock_irqsave(&asic->lock, flags);
+        raw_spin_lock_irqsave(&asic->lock, flags);
         edge = asic3_read_register(asic,
                                    base + ASIC3_GPIO_EDGE_TRIGGER);
         edge ^= bit;
         asic3_write_register(asic,
                              base + ASIC3_GPIO_EDGE_TRIGGER, edge);
-        spin_unlock_irqrestore(&asic->lock, flags);
+        raw_spin_unlock_irqrestore(&asic->lock, flags);
 }
 
 static void asic3_irq_demux(struct irq_desc *desc)
@@ -151,10 +151,10 @@ static void asic3_irq_demux(struct irq_desc *desc)
                 u32 status;
                 int bank;
 
-                spin_lock_irqsave(&asic->lock, flags);
+                raw_spin_lock_irqsave(&asic->lock, flags);
                 status = asic3_read_register(asic,
                                              ASIC3_OFFSET(INTR, P_INT_STAT));
-                spin_unlock_irqrestore(&asic->lock, flags);
+                raw_spin_unlock_irqrestore(&asic->lock, flags);
 
                 /* Check all ten register bits */
                 if ((status & 0x3ff) == 0)
@@ -167,7 +167,7 @@ static void asic3_irq_demux(struct irq_desc *desc)
 
                                 base = ASIC3_GPIO_A_BASE
                                        + bank * ASIC3_GPIO_BASE_INCR;
-                                spin_lock_irqsave(&asic->lock, flags);
+                                raw_spin_lock_irqsave(&asic->lock, flags);
                                 istat = asic3_read_register(asic,
                                                             base +
                                                             ASIC3_GPIO_INT_STATUS);
@@ -175,7 +175,7 @@ static void asic3_irq_demux(struct irq_desc *desc)
                                 asic3_write_register(asic,
                                                      base +
                                                      ASIC3_GPIO_INT_STATUS, 0);
-                                spin_unlock_irqrestore(&asic->lock, flags);
+                                raw_spin_unlock_irqrestore(&asic->lock, flags);
 
                                 for (i = 0; i < ASIC3_GPIOS_PER_BANK; i++) {
                                         int bit = (1 << i);
@@ -230,11 +230,11 @@ static void asic3_mask_gpio_irq(struct irq_data *data)
         bank = asic3_irq_to_bank(asic, data->irq);
         index = asic3_irq_to_index(asic, data->irq);
 
-        spin_lock_irqsave(&asic->lock, flags);
+        raw_spin_lock_irqsave(&asic->lock, flags);
         val = asic3_read_register(asic, bank + ASIC3_GPIO_MASK);
         val |= 1 << index;
         asic3_write_register(asic, bank + ASIC3_GPIO_MASK, val);
-        spin_unlock_irqrestore(&asic->lock, flags);
+        raw_spin_unlock_irqrestore(&asic->lock, flags);
 }
 
 static void asic3_mask_irq(struct irq_data *data)
@@ -243,7 +243,7 @@ static void asic3_mask_irq(struct irq_data *data)
         int regval;
         unsigned long flags;
 
-        spin_lock_irqsave(&asic->lock, flags);
+        raw_spin_lock_irqsave(&asic->lock, flags);
         regval = asic3_read_register(asic,
                                      ASIC3_INTR_BASE +
                                      ASIC3_INTR_INT_MASK);
@@ -255,7 +255,7 @@ static void asic3_mask_irq(struct irq_data *data)
                              ASIC3_INTR_BASE +
                              ASIC3_INTR_INT_MASK,
                              regval);
-        spin_unlock_irqrestore(&asic->lock, flags);
+        raw_spin_unlock_irqrestore(&asic->lock, flags);
 }
 
 static void asic3_unmask_gpio_irq(struct irq_data *data)
@@ -267,11 +267,11 @@ static void asic3_unmask_gpio_irq(struct irq_data *data)
         bank = asic3_irq_to_bank(asic, data->irq);
         index = asic3_irq_to_index(asic, data->irq);
 
-        spin_lock_irqsave(&asic->lock, flags);
+        raw_spin_lock_irqsave(&asic->lock, flags);
         val = asic3_read_register(asic, bank + ASIC3_GPIO_MASK);
         val &= ~(1 << index);
         asic3_write_register(asic, bank + ASIC3_GPIO_MASK, val);
-        spin_unlock_irqrestore(&asic->lock, flags);
+        raw_spin_unlock_irqrestore(&asic->lock, flags);
 }
 
 static void asic3_unmask_irq(struct irq_data *data)
@@ -280,7 +280,7 @@ static void asic3_unmask_irq(struct irq_data *data)
         int regval;
         unsigned long flags;
 
-        spin_lock_irqsave(&asic->lock, flags);
+        raw_spin_lock_irqsave(&asic->lock, flags);
         regval = asic3_read_register(asic,
                                      ASIC3_INTR_BASE +
                                      ASIC3_INTR_INT_MASK);
@@ -292,7 +292,7 @@ static void asic3_unmask_irq(struct irq_data *data)
                              ASIC3_INTR_BASE +
                              ASIC3_INTR_INT_MASK,
                              regval);
-        spin_unlock_irqrestore(&asic->lock, flags);
+        raw_spin_unlock_irqrestore(&asic->lock, flags);
 }
 
 static int asic3_gpio_irq_type(struct irq_data *data, unsigned int type)
@@ -306,7 +306,7 @@ static int asic3_gpio_irq_type(struct irq_data *data, unsigned int type)
         index = asic3_irq_to_index(asic, data->irq);
         bit = 1<<index;
 
-        spin_lock_irqsave(&asic->lock, flags);
+        raw_spin_lock_irqsave(&asic->lock, flags);
         level = asic3_read_register(asic,
                                     bank + ASIC3_GPIO_LEVEL_TRIGGER);
         edge = asic3_read_register(asic,
@@ -348,7 +348,7 @@ static int asic3_gpio_irq_type(struct irq_data *data, unsigned int type)
                              edge);
         asic3_write_register(asic, bank + ASIC3_GPIO_TRIGGER_TYPE,
                              trigger);
-        spin_unlock_irqrestore(&asic->lock, flags);
+        raw_spin_unlock_irqrestore(&asic->lock, flags);
         return 0;
 }
 
@@ -455,7 +455,7 @@ static int asic3_gpio_direction(struct gpio_chip *chip,
                 return -EINVAL;
         }
 
-        spin_lock_irqsave(&asic->lock, flags);
+        raw_spin_lock_irqsave(&asic->lock, flags);
 
         out_reg = asic3_read_register(asic, gpio_base + ASIC3_GPIO_DIRECTION);
 
@@ -467,7 +467,7 @@ static int asic3_gpio_direction(struct gpio_chip *chip,
 
         asic3_write_register(asic, gpio_base + ASIC3_GPIO_DIRECTION, out_reg);
 
-        spin_unlock_irqrestore(&asic->lock, flags);
+        raw_spin_unlock_irqrestore(&asic->lock, flags);
 
         return 0;
 
@@ -524,7 +524,7 @@ static void asic3_gpio_set(struct gpio_chip *chip,
 
         mask = ASIC3_GPIO_TO_MASK(offset);
 
-        spin_lock_irqsave(&asic->lock, flags);
+        raw_spin_lock_irqsave(&asic->lock, flags);
 
         out_reg = asic3_read_register(asic, gpio_base + ASIC3_GPIO_OUT);
 
@@ -535,7 +535,7 @@ static void asic3_gpio_set(struct gpio_chip *chip,
 
         asic3_write_register(asic, gpio_base + ASIC3_GPIO_OUT, out_reg);
 
-        spin_unlock_irqrestore(&asic->lock, flags);
+        raw_spin_unlock_irqrestore(&asic->lock, flags);
 }
 
 static int asic3_gpio_to_irq(struct gpio_chip *chip, unsigned offset)
@@ -611,13 +611,13 @@ static void asic3_clk_enable(struct asic3 *asic, struct asic3_clk *clk)
         unsigned long flags;
         u32 cdex;
 
-        spin_lock_irqsave(&asic->lock, flags);
+        raw_spin_lock_irqsave(&asic->lock, flags);
         if (clk->enabled++ == 0) {
                 cdex = asic3_read_register(asic, ASIC3_OFFSET(CLOCK, CDEX));
                 cdex |= clk->cdex;
                 asic3_write_register(asic, ASIC3_OFFSET(CLOCK, CDEX), cdex);
         }
-        spin_unlock_irqrestore(&asic->lock, flags);
+        raw_spin_unlock_irqrestore(&asic->lock, flags);
 }
 
 static void asic3_clk_disable(struct asic3 *asic, struct asic3_clk *clk)
@@ -627,13 +627,13 @@ static void asic3_clk_disable(struct asic3 *asic, struct asic3_clk *clk)
 
         WARN_ON(clk->enabled == 0);
 
-        spin_lock_irqsave(&asic->lock, flags);
+        raw_spin_lock_irqsave(&asic->lock, flags);
         if (--clk->enabled == 0) {
                 cdex = asic3_read_register(asic, ASIC3_OFFSET(CLOCK, CDEX));
                 cdex &= ~clk->cdex;
                 asic3_write_register(asic, ASIC3_OFFSET(CLOCK, CDEX), cdex);
         }
-        spin_unlock_irqrestore(&asic->lock, flags);
+        raw_spin_unlock_irqrestore(&asic->lock, flags);
 }
 
 /* MFD cells (SPI, PWM, LED, DS1WM, MMC) */
@@ -963,7 +963,7 @@ static int __init asic3_probe(struct platform_device *pdev)
         if (!asic)
                 return -ENOMEM;
 
-        spin_lock_init(&asic->lock);
+        raw_spin_lock_init(&asic->lock);
         platform_set_drvdata(pdev, asic);
         asic->dev = &pdev->dev;