1 files changed, 73 insertions, 120 deletions

diff --git a/arch/mips/rb532/gpio.c b/arch/mips/rb532/gpio.c
index 70c4a67..0e84c8a 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;
 }