[ARM] Orion: share GPIO IRQ handling code

Split off Orion GPIO IRQ handling code into plat-orion/.
Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
Signed-off-by: Nicolas Pitre <nico@marvell.com>

arch/arm/mach-orion5x/include/mach/gpio.h

@@ -19,6 +19,9 @@
 #define GPIO_BLINK_EN(pin)	ORION5X_DEV_BUS_REG(0x108)
 #define GPIO_IN_POL(pin)	ORION5X_DEV_BUS_REG(0x10c)
 #define GPIO_DATA_IN(pin)	ORION5X_DEV_BUS_REG(0x110)
+#define GPIO_EDGE_CAUSE(pin)	ORION5X_DEV_BUS_REG(0x114)
+#define GPIO_EDGE_MASK(pin)	ORION5X_DEV_BUS_REG(0x118)
+#define GPIO_LEVEL_MASK(pin)	ORION5X_DEV_BUS_REG(0x11c)
 
 static inline int gpio_to_irq(int pin)
 {

arch/arm/mach-orion5x/include/mach/orion5x.h

@@ -134,9 +134,6 @@
 #define MPP_16_19_CTRL		ORION5X_DEV_BUS_REG(0x050)
 #define MPP_DEV_CTRL		ORION5X_DEV_BUS_REG(0x008)
 #define MPP_RESET_SAMPLE	ORION5X_DEV_BUS_REG(0x010)
-#define GPIO_EDGE_CAUSE		ORION5X_DEV_BUS_REG(0x114)
-#define GPIO_EDGE_MASK		ORION5X_DEV_BUS_REG(0x118)
-#define GPIO_LEVEL_MASK		ORION5X_DEV_BUS_REG(0x11c)
 #define DEV_BANK_0_PARAM	ORION5X_DEV_BUS_REG(0x45c)
 #define DEV_BANK_1_PARAM	ORION5X_DEV_BUS_REG(0x460)
 #define DEV_BANK_2_PARAM	ORION5X_DEV_BUS_REG(0x464)

arch/arm/mach-orion5x/irq.c

@@ -19,193 +19,38 @@
 #include <plat/irq.h>
 #include "common.h"
 
-/*****************************************************************************
- * Orion GPIO IRQ
- *
- * GPIO_IN_POL register controls whether GPIO_DATA_IN will hold the same
- * value of the line or the opposite value.
- *
- * Level IRQ handlers: DATA_IN is used directly as cause register.
- *                     Interrupt are masked by LEVEL_MASK registers.
- * Edge IRQ handlers:  Change in DATA_IN are latched in EDGE_CAUSE.
- *                     Interrupt are masked by EDGE_MASK registers.
- * Both-edge handlers: Similar to regular Edge handlers, but also swaps
- *                     the polarity to catch the next line transaction.
- *                     This is a race condition that might not perfectly
- *                     work on some use cases.
- *
- * Every eight GPIO lines are grouped (OR'ed) before going up to main
- * cause register.
- *
- *                    EDGE  cause    mask
- *        data-in   /--------| |-----| |----\
- *     -----| |-----                         ---- to main cause reg
- *           X      \----------------| |----/
- *        polarity    LEVEL          mask
- *
- ****************************************************************************/
-static void orion5x_gpio_irq_ack(u32 irq)
-{
-	int pin = irq_to_gpio(irq);
-	if (irq_desc[irq].status & IRQ_LEVEL)
-		/*
-		 * Mask bit for level interrupt
-		 */
-		orion5x_clrbits(GPIO_LEVEL_MASK, 1 << pin);
-	else
-		/*
-		 * Clear casue bit for egde interrupt
-		 */
-		orion5x_clrbits(GPIO_EDGE_CAUSE, 1 << pin);
-}
-
-static void orion5x_gpio_irq_mask(u32 irq)
-{
-	int pin = irq_to_gpio(irq);
-	if (irq_desc[irq].status & IRQ_LEVEL)
-		orion5x_clrbits(GPIO_LEVEL_MASK, 1 << pin);
-	else
-		orion5x_clrbits(GPIO_EDGE_MASK, 1 << pin);
-}
-
-static void orion5x_gpio_irq_unmask(u32 irq)
+static void gpio_irq_handler(unsigned int irq, struct irq_desc *desc)
 {
-	int pin = irq_to_gpio(irq);
-	if (irq_desc[irq].status & IRQ_LEVEL)
-		orion5x_setbits(GPIO_LEVEL_MASK, 1 << pin);
-	else
-		orion5x_setbits(GPIO_EDGE_MASK, 1 << pin);
-}
-
-static int orion5x_gpio_set_irq_type(u32 irq, u32 type)
-{
-	int pin = irq_to_gpio(irq);
-	struct irq_desc *desc;
-
-	if ((readl(GPIO_IO_CONF(pin)) & (1 << pin)) == 0) {
-		printk(KERN_ERR "orion5x_gpio_set_irq_type failed "
-				"(irq %d, pin %d).\n", irq, pin);
-		return -EINVAL;
-	}
-
-	desc = irq_desc + irq;
-
-	switch (type) {
-	case IRQ_TYPE_LEVEL_HIGH:
-		desc->handle_irq = handle_level_irq;
-		desc->status |= IRQ_LEVEL;
-		orion5x_clrbits(GPIO_IN_POL(pin), (1 << pin));
-		break;
-	case IRQ_TYPE_LEVEL_LOW:
-		desc->handle_irq = handle_level_irq;
-		desc->status |= IRQ_LEVEL;
-		orion5x_setbits(GPIO_IN_POL(pin), (1 << pin));
-		break;
-	case IRQ_TYPE_EDGE_RISING:
-		desc->handle_irq = handle_edge_irq;
-		desc->status &= ~IRQ_LEVEL;
-		orion5x_clrbits(GPIO_IN_POL(pin), (1 << pin));
-		break;
-	case IRQ_TYPE_EDGE_FALLING:
-		desc->handle_irq = handle_edge_irq;
-		desc->status &= ~IRQ_LEVEL;
-		orion5x_setbits(GPIO_IN_POL(pin), (1 << pin));
-		break;
-	case IRQ_TYPE_EDGE_BOTH:
-		desc->handle_irq = handle_edge_irq;
-		desc->status &= ~IRQ_LEVEL;
-		/*
-		 * set initial polarity based on current input level
-		 */
-		if ((readl(GPIO_IN_POL(pin)) ^ readl(GPIO_DATA_IN(pin)))
-		    & (1 << pin))
-			orion5x_setbits(GPIO_IN_POL(pin), (1 << pin)); /* falling */
-		else
-			orion5x_clrbits(GPIO_IN_POL(pin), (1 << pin)); /* rising */
-
-		break;
-	default:
-		printk(KERN_ERR "failed to set irq=%d (type=%d)\n", irq, type);
-		return -EINVAL;
-	}
-
-	desc->status &= ~IRQ_TYPE_SENSE_MASK;
-	desc->status |= type & IRQ_TYPE_SENSE_MASK;
-
-	return 0;
-}
-
-static struct irq_chip orion5x_gpio_irq_chip = {
-	.name		= "Orion-IRQ-GPIO",
-	.ack		= orion5x_gpio_irq_ack,
-	.mask		= orion5x_gpio_irq_mask,
-	.unmask		= orion5x_gpio_irq_unmask,
-	.set_type	= orion5x_gpio_set_irq_type,
-};
-
-static void orion5x_gpio_irq_handler(unsigned int irq, struct irq_desc *desc)
-{
-	u32 cause, offs, pin;
-
 	BUG_ON(irq < IRQ_ORION5X_GPIO_0_7 || irq > IRQ_ORION5X_GPIO_24_31);
-	offs = (irq - IRQ_ORION5X_GPIO_0_7) * 8;
-	cause = (readl(GPIO_DATA_IN(offs)) & readl(GPIO_LEVEL_MASK)) |
-		(readl(GPIO_EDGE_CAUSE) & readl(GPIO_EDGE_MASK));
 
-	for (pin = offs; pin < offs + 8; pin++) {
-		if (cause & (1 << pin)) {
-			irq = gpio_to_irq(pin);
-			desc = irq_desc + irq;
-			if ((desc->status & IRQ_TYPE_SENSE_MASK) == IRQ_TYPE_EDGE_BOTH) {
-				/* Swap polarity (race with GPIO line) */
-				u32 polarity = readl(GPIO_IN_POL(pin));
-				polarity ^= 1 << pin;
-				writel(polarity, GPIO_IN_POL(pin));
-			}
-			generic_handle_irq(irq);
-		}
-	}
+	orion_gpio_irq_handler((irq - IRQ_ORION5X_GPIO_0_7) << 3);
 }
 
-static void __init orion5x_init_gpio_irq(void)
+void __init orion5x_init_irq(void)
 {
 	int i;
-	struct irq_desc *desc;
+
+	orion_irq_init(0, (void __iomem *)MAIN_IRQ_MASK);
 
 	/*
 	 * Mask and clear GPIO IRQ interrupts
 	 */
-	writel(0x0, GPIO_LEVEL_MASK);
-	writel(0x0, GPIO_EDGE_MASK);
-	writel(0x0, GPIO_EDGE_CAUSE);
+	writel(0x0, GPIO_LEVEL_MASK(0));
+	writel(0x0, GPIO_EDGE_MASK(0));
+	writel(0x0, GPIO_EDGE_CAUSE(0));
 
 	/*
 	 * Register chained level handlers for GPIO IRQs by default.
 	 * User can use set_type() if he wants to use edge types handlers.
 	 */
 	for (i = IRQ_ORION5X_GPIO_START; i < NR_IRQS; i++) {
-		set_irq_chip(i, &orion5x_gpio_irq_chip);
+		set_irq_chip(i, &orion_gpio_irq_level_chip);
 		set_irq_handler(i, handle_level_irq);
-		desc = irq_desc + i;
-		desc->status |= IRQ_LEVEL;
+		irq_desc[i].status |= IRQ_LEVEL;
 		set_irq_flags(i, IRQF_VALID);
 	}
-	set_irq_chained_handler(IRQ_ORION5X_GPIO_0_7, orion5x_gpio_irq_handler);
-	set_irq_chained_handler(IRQ_ORION5X_GPIO_8_15, orion5x_gpio_irq_handler);
-	set_irq_chained_handler(IRQ_ORION5X_GPIO_16_23, orion5x_gpio_irq_handler);
-	set_irq_chained_handler(IRQ_ORION5X_GPIO_24_31, orion5x_gpio_irq_handler);
-}
-
-/*****************************************************************************
- * Orion Main IRQ
- ****************************************************************************/
-static void __init orion5x_init_main_irq(void)
-{
-	orion_irq_init(0, (void __iomem *)MAIN_IRQ_MASK);
-}
-
-void __init orion5x_init_irq(void)
-{
-	orion5x_init_main_irq();
-	orion5x_init_gpio_irq();
+	set_irq_chained_handler(IRQ_ORION5X_GPIO_0_7, gpio_irq_handler);
+	set_irq_chained_handler(IRQ_ORION5X_GPIO_8_15, gpio_irq_handler);
+	set_irq_chained_handler(IRQ_ORION5X_GPIO_16_23, gpio_irq_handler);
+	set_irq_chained_handler(IRQ_ORION5X_GPIO_24_31, gpio_irq_handler);
 }

arch/arm/plat-orion/gpio.c

@@ -10,6 +10,7 @@
 
 #include <linux/kernel.h>
 #include <linux/init.h>
+#include <linux/irq.h>
 #include <linux/module.h>
 #include <linux/spinlock.h>
 #include <linux/bitops.h>
@@ -237,3 +238,178 @@ void orion_gpio_set_blink(unsigned pin, int blink)
 	spin_unlock_irqrestore(&gpio_lock, flags);
 }
 EXPORT_SYMBOL(orion_gpio_set_blink);
+
+
+/*****************************************************************************
+ * Orion GPIO IRQ
+ *
+ * GPIO_IN_POL register controls whether GPIO_DATA_IN will hold the same
+ * value of the line or the opposite value.
+ *
+ * Level IRQ handlers: DATA_IN is used directly as cause register.
+ *                     Interrupt are masked by LEVEL_MASK registers.
+ * Edge IRQ handlers:  Change in DATA_IN are latched in EDGE_CAUSE.
+ *                     Interrupt are masked by EDGE_MASK registers.
+ * Both-edge handlers: Similar to regular Edge handlers, but also swaps
+ *                     the polarity to catch the next line transaction.
+ *                     This is a race condition that might not perfectly
+ *                     work on some use cases.
+ *
+ * Every eight GPIO lines are grouped (OR'ed) before going up to main
+ * cause register.
+ *
+ *                    EDGE  cause    mask
+ *        data-in   /--------| |-----| |----\
+ *     -----| |-----                         ---- to main cause reg
+ *           X      \----------------| |----/
+ *        polarity    LEVEL          mask
+ *
+ ****************************************************************************/
+static void gpio_irq_edge_ack(u32 irq)
+{
+	int pin = irq_to_gpio(irq);
+
+	writel(~(1 << (pin & 31)), GPIO_EDGE_CAUSE(pin));
+}
+
+static void gpio_irq_edge_mask(u32 irq)
+{
+	int pin = irq_to_gpio(irq);
+	u32 u;
+
+	u = readl(GPIO_EDGE_MASK(pin));
+	u &= ~(1 << (pin & 31));
+	writel(u, GPIO_EDGE_MASK(pin));
+}
+
+static void gpio_irq_edge_unmask(u32 irq)
+{
+	int pin = irq_to_gpio(irq);
+	u32 u;
+
+	u = readl(GPIO_EDGE_MASK(pin));
+	u |= 1 << (pin & 31);
+	writel(u, GPIO_EDGE_MASK(pin));
+}
+
+static void gpio_irq_level_mask(u32 irq)
+{
+	int pin = irq_to_gpio(irq);
+	u32 u;
+
+	u = readl(GPIO_LEVEL_MASK(pin));
+	u &= ~(1 << (pin & 31));
+	writel(u, GPIO_LEVEL_MASK(pin));
+}
+
+static void gpio_irq_level_unmask(u32 irq)
+{
+	int pin = irq_to_gpio(irq);
+	u32 u;
+
+	u = readl(GPIO_LEVEL_MASK(pin));
+	u |= 1 << (pin & 31);
+	writel(u, GPIO_LEVEL_MASK(pin));
+}
+
+static int gpio_irq_set_type(u32 irq, u32 type)
+{
+	int pin = irq_to_gpio(irq);
+	struct irq_desc *desc;
+	u32 u;
+
+	u = readl(GPIO_IO_CONF(pin)) & (1 << (pin & 31));
+	if (!u) {
+		printk(KERN_ERR "orion gpio_irq_set_type failed "
+				"(irq %d, pin %d).\n", irq, pin);
+		return -EINVAL;
+	}
+
+	desc = irq_desc + irq;
+
+	/*
+	 * Set edge/level type.
+	 */
+	if (type & (IRQ_TYPE_EDGE_RISING | IRQ_TYPE_EDGE_FALLING)) {
+		desc->chip = &orion_gpio_irq_edge_chip;
+	} else if (type & (IRQ_TYPE_LEVEL_HIGH | IRQ_TYPE_LEVEL_LOW)) {
+		desc->chip = &orion_gpio_irq_level_chip;
+	} else {
+		printk(KERN_ERR "failed to set irq=%d (type=%d)\n", irq, type);
+		return -EINVAL;
+	}
+
+	/*
+	 * Configure interrupt polarity.
+	 */
+	if (type == IRQ_TYPE_EDGE_RISING || type == IRQ_TYPE_LEVEL_HIGH) {
+		u = readl(GPIO_IN_POL(pin));
+		u &= ~(1 << (pin & 31));
+		writel(u, GPIO_IN_POL(pin));
+	} else if (type == IRQ_TYPE_EDGE_FALLING || type == IRQ_TYPE_LEVEL_LOW) {
+		u = readl(GPIO_IN_POL(pin));
+		u |= 1 << (pin & 31);
+		writel(u, GPIO_IN_POL(pin));
+	} else if (type == IRQ_TYPE_EDGE_BOTH) {
+		u32 v;
+
+		v = readl(GPIO_IN_POL(pin)) ^ readl(GPIO_DATA_IN(pin));
+
+		/*
+		 * set initial polarity based on current input level
+		 */
+		u = readl(GPIO_IN_POL(pin));
+		if (v & (1 << (pin & 31)))
+			u |= 1 << (pin & 31);		/* falling */
+		else
+			u &= ~(1 << (pin & 31));	/* rising */
+		writel(u, GPIO_IN_POL(pin));
+	}
+
+	desc->status = (desc->status & ~IRQ_TYPE_SENSE_MASK) | type;
+
+	return 0;
+}
+
+struct irq_chip orion_gpio_irq_edge_chip = {
+	.name		= "orion_gpio_irq_edge",
+	.ack		= gpio_irq_edge_ack,
+	.mask		= gpio_irq_edge_mask,
+	.unmask		= gpio_irq_edge_unmask,
+	.set_type	= gpio_irq_set_type,
+};
+
+struct irq_chip orion_gpio_irq_level_chip = {
+	.name		= "orion_gpio_irq_level",
+	.mask		= gpio_irq_level_mask,
+	.mask_ack	= gpio_irq_level_mask,
+	.unmask		= gpio_irq_level_unmask,
+	.set_type	= gpio_irq_set_type,
+};
+
+void orion_gpio_irq_handler(int pinoff)
+{
+	u32 cause;
+	int pin;
+
+	cause = readl(GPIO_DATA_IN(pinoff)) & readl(GPIO_LEVEL_MASK(pinoff));
+	cause |= readl(GPIO_EDGE_CAUSE(pinoff)) & readl(GPIO_EDGE_MASK(pinoff));
+
+	for (pin = pinoff; pin < pinoff + 8; pin++) {
+		int irq = gpio_to_irq(pin);
+		struct irq_desc *desc = irq_desc + irq;
+
+		if (!(cause & (1 << (pin & 31))))
+			continue;
+
+		if ((desc->status & IRQ_TYPE_SENSE_MASK) == IRQ_TYPE_EDGE_BOTH) {
+			/* Swap polarity (race with GPIO line) */
+			u32 polarity;
+
+			polarity = readl(GPIO_IN_POL(pin));
+			polarity ^= 1 << (pin & 31);
+			writel(polarity, GPIO_IN_POL(pin));
+		}
+		desc_handle_irq(irq, desc);
+	}
+}

arch/arm/plat-orion/include/plat/gpio.h

@@ -28,5 +28,12 @@ void orion_gpio_set_unused(unsigned pin);
 void orion_gpio_set_valid(unsigned pin, int valid);
 void orion_gpio_set_blink(unsigned pin, int blink);
 
+/*
+ * GPIO interrupt handling.
+ */
+extern struct irq_chip orion_gpio_irq_edge_chip;
+extern struct irq_chip orion_gpio_irq_level_chip;
+void orion_gpio_irq_handler(int irqoff);
+
 
 #endif