1 files changed, 73 insertions, 120 deletions

diff --git a/arch/mips/rb532/gpio.c b/arch/mips/rb532/gpio.c
index 70c4a6726377..0e84c8ab6a39 100644
--- a/arch/mips/rb532/gpio.c
+++ b/arch/mips/rb532/gpio.c
@@ -39,10 +39,6 @@
 struct rb532_gpio_chip {
         struct gpio_chip chip;
         void __iomem     *regbase;
-        void            (*set_int_level)(struct gpio_chip *chip, unsigned offset, int value);
-        int             (*get_int_level)(struct gpio_chip *chip, unsigned offset);
-        void            (*set_int_status)(struct gpio_chip *chip, unsigned offset, int value);
-        int             (*get_int_status)(struct gpio_chip *chip, unsigned offset);
 };
 
 struct mpmc_device dev3;
@@ -111,15 +107,47 @@ unsigned char get_latch_u5(void)
 }
 EXPORT_SYMBOL(get_latch_u5);
 
+/* rb532_set_bit - sanely set a bit
+ *
+ * bitval: new value for the bit
+ * offset: bit index in the 4 byte address range
+ * ioaddr: 4 byte aligned address being altered
+ */
+static inline void rb532_set_bit(unsigned bitval,
+                unsigned offset, void __iomem *ioaddr)
+{
+        unsigned long flags;
+        u32 val;
+
+        bitval = !!bitval;              /* map parameter to {0,1} */
+
+        local_irq_save(flags);
+
+        val = readl(ioaddr);
+        val &= ~( ~bitval << offset );   /* unset bit if bitval == 0 */
+        val |=  (  bitval << offset );   /* set bit if bitval == 1 */
+        writel(val, ioaddr);
+
+        local_irq_restore(flags);
+}
+
+/* rb532_get_bit - read a bit
+ *
+ * returns the boolean state of the bit, which may be > 1
+ */
+static inline int rb532_get_bit(unsigned offset, void __iomem *ioaddr)
+{
+        return (readl(ioaddr) & (1 << offset));
+}
+
 /*
  * Return GPIO level */
 static int rb532_gpio_get(struct gpio_chip *chip, unsigned offset)
 {
-        u32                     mask = 1 << offset;
         struct rb532_gpio_chip  *gpch;
 
         gpch = container_of(chip, struct rb532_gpio_chip, chip);
-        return readl(gpch->regbase + GPIOD) & mask;
+        return rb532_get_bit(offset, gpch->regbase + GPIOD);
 }
 
 /*
@@ -128,23 +156,10 @@ static int rb532_gpio_get(struct gpio_chip *chip, unsigned offset)
 static void rb532_gpio_set(struct gpio_chip *chip,
                                 unsigned offset, int value)
 {
-        unsigned long           flags;
-        u32                     mask = 1 << offset;
-        u32                     tmp;
         struct rb532_gpio_chip  *gpch;
-        void __iomem            *gpvr;
 
         gpch = container_of(chip, struct rb532_gpio_chip, chip);
-        gpvr = gpch->regbase + GPIOD;
-
-        local_irq_save(flags);
-        tmp = readl(gpvr);
-        if (value)
-                tmp |= mask;
-        else
-                tmp &= ~mask;
-        writel(tmp, gpvr);
-        local_irq_restore(flags);
+        rb532_set_bit(value, offset, gpch->regbase + GPIOD);
 }
 
 /*
@@ -152,21 +167,14 @@ static void rb532_gpio_set(struct gpio_chip *chip,
  */
 static int rb532_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
 {
-        unsigned long           flags;
-        u32                     mask = 1 << offset;
-        u32                     value;
         struct rb532_gpio_chip  *gpch;
-        void __iomem            *gpdr;
 
         gpch = container_of(chip, struct rb532_gpio_chip, chip);
-        gpdr = gpch->regbase + GPIOCFG;
 
-        local_irq_save(flags);
-        value = readl(gpdr);
-        value &= ~mask;
-        writel(value, gpdr);
-        local_irq_restore(flags);
+        if (rb532_get_bit(offset, gpch->regbase + GPIOFUNC))
+                return 1;       /* alternate function, GPIOCFG is ignored */
 
+        rb532_set_bit(0, offset, gpch->regbase + GPIOCFG);
         return 0;
 }
 
@@ -176,117 +184,60 @@ static int rb532_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
 static int rb532_gpio_direction_output(struct gpio_chip *chip,
                                         unsigned offset, int value)
 {
-        unsigned long           flags;
-        u32                     mask = 1 << offset;
-        u32                     tmp;
         struct rb532_gpio_chip  *gpch;
-        void __iomem            *gpdr;
 
         gpch = container_of(chip, struct rb532_gpio_chip, chip);
-        writel(mask, gpch->regbase + GPIOD);
-        gpdr = gpch->regbase + GPIOCFG;
 
-        local_irq_save(flags);
-        tmp = readl(gpdr);
-        tmp |= mask;
-        writel(tmp, gpdr);
-        local_irq_restore(flags);
+        if (rb532_get_bit(offset, gpch->regbase + GPIOFUNC))
+                return 1;       /* alternate function, GPIOCFG is ignored */
 
+        /* set the initial output value */
+        rb532_set_bit(value, offset, gpch->regbase + GPIOD);
+
+        rb532_set_bit(1, offset, gpch->regbase + GPIOCFG);
         return 0;
 }
 
-/*
- * Set the GPIO interrupt level
- */
-static void rb532_gpio_set_int_level(struct gpio_chip *chip,
-                                        unsigned offset, int value)
-{
-        unsigned long           flags;
-        u32                     mask = 1 << offset;
-        u32                     tmp;
-        struct rb532_gpio_chip  *gpch;
-        void __iomem            *gpil;
-
-        gpch = container_of(chip, struct rb532_gpio_chip, chip);
-        gpil = gpch->regbase + GPIOILEVEL;
-
-        local_irq_save(flags);
-        tmp = readl(gpil);
-        if (value)
-                tmp |= mask;
-        else
-                tmp &= ~mask;
-        writel(tmp, gpil);
-        local_irq_restore(flags);
-}
+static struct rb532_gpio_chip rb532_gpio_chip[] = {
+        [0] = {
+                .chip = {
+                        .label                  = "gpio0",
+                        .direction_input        = rb532_gpio_direction_input,
+                        .direction_output       = rb532_gpio_direction_output,
+                        .get                    = rb532_gpio_get,
+                        .set                    = rb532_gpio_set,
+                        .base                   = 0,
+                        .ngpio                  = 32,
+                },
+        },
+};
 
 /*
- * Get the GPIO interrupt level
+ * Set GPIO interrupt level
  */
-static int rb532_gpio_get_int_level(struct gpio_chip *chip, unsigned offset)
+void rb532_gpio_set_ilevel(int bit, unsigned gpio)
 {
-        u32                     mask = 1 << offset;
-        struct rb532_gpio_chip  *gpch;
-
-        gpch = container_of(chip, struct rb532_gpio_chip, chip);
-        return readl(gpch->regbase + GPIOILEVEL) & mask;
+        rb532_set_bit(bit, gpio, rb532_gpio_chip->regbase + GPIOILEVEL);
 }
+EXPORT_SYMBOL(rb532_gpio_set_ilevel);
 
 /*
- * Set the GPIO interrupt status
+ * Set GPIO interrupt status
  */
-static void rb532_gpio_set_int_status(struct gpio_chip *chip,
-                                unsigned offset, int value)
+void rb532_gpio_set_istat(int bit, unsigned gpio)
 {
-        unsigned long           flags;
-        u32                     mask = 1 << offset;
-        u32                     tmp;
-        struct rb532_gpio_chip  *gpch;
-        void __iomem            *gpis;
-
-        gpch = container_of(chip, struct rb532_gpio_chip, chip);
-        gpis = gpch->regbase + GPIOISTAT;
-
-        local_irq_save(flags);
-        tmp = readl(gpis);
-        if (value)
-                tmp |= mask;
-        else
-                tmp &= ~mask;
-        writel(tmp, gpis);
-        local_irq_restore(flags);
+        rb532_set_bit(bit, gpio, rb532_gpio_chip->regbase + GPIOISTAT);
 }
+EXPORT_SYMBOL(rb532_gpio_set_istat);
 
 /*
- * Get the GPIO interrupt status
+ * Configure GPIO alternate function
  */
-static int rb532_gpio_get_int_status(struct gpio_chip *chip, unsigned offset)
+static void rb532_gpio_set_func(int bit, unsigned gpio)
 {
-        u32                     mask = 1 << offset;
-        struct rb532_gpio_chip  *gpch;
-
-        gpch = container_of(chip, struct rb532_gpio_chip, chip);
-        return readl(gpch->regbase + GPIOISTAT) & mask;
+       rb532_set_bit(bit, gpio, rb532_gpio_chip->regbase + GPIOFUNC);
 }
 
-static struct rb532_gpio_chip rb532_gpio_chip[] = {
-        [0] = {
-                .chip = {
-                        .label                  = "gpio0",
-                        .direction_input        = rb532_gpio_direction_input,
-                        .direction_output       = rb532_gpio_direction_output,
-                        .get                    = rb532_gpio_get,
-                        .set                    = rb532_gpio_set,
-                        .base                   = 0,
-                        .ngpio                  = 32,
-                },
-                .get_int_level          = rb532_gpio_get_int_level,
-                .set_int_level          = rb532_gpio_set_int_level,
-                .get_int_status         = rb532_gpio_get_int_status,
-                .set_int_status         = rb532_gpio_set_int_status,
-        },
-};
-
 int __init rb532_gpio_init(void)
 {
         struct resource *r;
@@ -310,9 +261,11 @@ int __init rb532_gpio_init(void)
                 return -ENXIO;
         }
 
-        /* Set the interrupt status and level for the CF pin */
-        rb532_gpio_set_int_level(&rb532_gpio_chip->chip, CF_GPIO_NUM, 1);
-        rb532_gpio_set_int_status(&rb532_gpio_chip->chip, CF_GPIO_NUM, 0);
+        /* configure CF_GPIO_NUM as CFRDY IRQ source */
+        rb532_gpio_set_func(0, CF_GPIO_NUM);
+        rb532_gpio_direction_input(&rb532_gpio_chip->chip, CF_GPIO_NUM);
+        rb532_gpio_set_ilevel(1, CF_GPIO_NUM);
+        rb532_gpio_set_istat(0, CF_GPIO_NUM);
 
         return 0;
 }