ARM: 8281/1: sa1100: move GPIO-related IRQ code to gpio driver

As a part of driver consolidation, move GPIO-related IRQ code to
drivers/gpio/gpio-sa1100.c. The code does not use GPIOLIB_IRQCHIP (yet),
because sa1100 does not have a device for gpios, which is a requirement
for GPIOLIB_IRQCHIP. This will be the next step.

Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
Tested-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

1 files changed, 197 insertions, 0 deletions

diff --git a/drivers/gpio/gpio-sa1100.c b/drivers/gpio/gpio-sa1100.c
index 5b5d3c7bb84e..bec397a60204 100644
--- a/drivers/gpio/gpio-sa1100.c
+++ b/drivers/gpio/gpio-sa1100.c
@@ -11,6 +11,7 @@
 #include <linux/init.h>
 #include <linux/module.h>
 #include <linux/io.h>
+#include <linux/syscore_ops.h>
 #include <mach/hardware.h>
 #include <mach/irqs.h>
 
@@ -64,7 +65,203 @@ static struct gpio_chip sa1100_gpio_chip = {
 	.ngpio			= GPIO_MAX + 1,
 };
 
+/*
+ * SA1100 GPIO edge detection for IRQs:
+ * IRQs are generated on Falling-Edge, Rising-Edge, or both.
+ * Use this instead of directly setting GRER/GFER.
+ */
+static int GPIO_IRQ_rising_edge;
+static int GPIO_IRQ_falling_edge;
+static int GPIO_IRQ_mask;
+
+static int sa1100_gpio_type(struct irq_data *d, unsigned int type)
+{
+	unsigned int mask;
+
+	mask = BIT(d->hwirq);
+
+	if (type == IRQ_TYPE_PROBE) {
+		if ((GPIO_IRQ_rising_edge | GPIO_IRQ_falling_edge) & mask)
+			return 0;
+		type = IRQ_TYPE_EDGE_RISING | IRQ_TYPE_EDGE_FALLING;
+	}
+
+	if (type & IRQ_TYPE_EDGE_RISING)
+		GPIO_IRQ_rising_edge |= mask;
+	else
+		GPIO_IRQ_rising_edge &= ~mask;
+	if (type & IRQ_TYPE_EDGE_FALLING)
+		GPIO_IRQ_falling_edge |= mask;
+	else
+		GPIO_IRQ_falling_edge &= ~mask;
+
+	GRER = GPIO_IRQ_rising_edge & GPIO_IRQ_mask;
+	GFER = GPIO_IRQ_falling_edge & GPIO_IRQ_mask;
+
+	return 0;
+}
+
+/*
+ * GPIO IRQs must be acknowledged.
+ */
+static void sa1100_gpio_ack(struct irq_data *d)
+{
+	GEDR = BIT(d->hwirq);
+}
+
+static void sa1100_gpio_mask(struct irq_data *d)
+{
+	unsigned int mask = BIT(d->hwirq);
+
+	GPIO_IRQ_mask &= ~mask;
+
+	GRER &= ~mask;
+	GFER &= ~mask;
+}
+
+static void sa1100_gpio_unmask(struct irq_data *d)
+{
+	unsigned int mask = BIT(d->hwirq);
+
+	GPIO_IRQ_mask |= mask;
+
+	GRER = GPIO_IRQ_rising_edge & GPIO_IRQ_mask;
+	GFER = GPIO_IRQ_falling_edge & GPIO_IRQ_mask;
+}
+
+static int sa1100_gpio_wake(struct irq_data *d, unsigned int on)
+{
+	if (on)
+		PWER |= BIT(d->hwirq);
+	else
+		PWER &= ~BIT(d->hwirq);
+	return 0;
+}
+
+/*
+ * This is for GPIO IRQs
+ */
+static struct irq_chip sa1100_gpio_irq_chip = {
+	.name		= "GPIO",
+	.irq_ack	= sa1100_gpio_ack,
+	.irq_mask	= sa1100_gpio_mask,
+	.irq_unmask	= sa1100_gpio_unmask,
+	.irq_set_type	= sa1100_gpio_type,
+	.irq_set_wake	= sa1100_gpio_wake,
+};
+
+static int sa1100_gpio_irqdomain_map(struct irq_domain *d,
+		unsigned int irq, irq_hw_number_t hwirq)
+{
+	irq_set_chip_and_handler(irq, &sa1100_gpio_irq_chip,
+				 handle_edge_irq);
+	set_irq_flags(irq, IRQF_VALID | IRQF_PROBE);
+
+	return 0;
+}
+
+static struct irq_domain_ops sa1100_gpio_irqdomain_ops = {
+	.map = sa1100_gpio_irqdomain_map,
+	.xlate = irq_domain_xlate_onetwocell,
+};
+
+static struct irq_domain *sa1100_gpio_irqdomain;
+
+/*
+ * IRQ 0-11 (GPIO) handler.  We enter here with the
+ * irq_controller_lock held, and IRQs disabled.  Decode the IRQ
+ * and call the handler.
+ */
+static void
+sa1100_gpio_handler(unsigned int irq, struct irq_desc *desc)
+{
+	unsigned int mask;
+
+	mask = GEDR;
+	do {
+		/*
+		 * clear down all currently active IRQ sources.
+		 * We will be processing them all.
+		 */
+		GEDR = mask;
+
+		irq = IRQ_GPIO0;
+		do {
+			if (mask & 1)
+				generic_handle_irq(irq);
+			mask >>= 1;
+			irq++;
+		} while (mask);
+
+		mask = GEDR;
+	} while (mask);
+}
+
+static int sa1100_gpio_suspend(void)
+{
+	/*
+	 * Set the appropriate edges for wakeup.
+	 */
+	GRER = PWER & GPIO_IRQ_rising_edge;
+	GFER = PWER & GPIO_IRQ_falling_edge;
+
+	/*
+	 * Clear any pending GPIO interrupts.
+	 */
+	GEDR = GEDR;
+
+	return 0;
+}
+
+static void sa1100_gpio_resume(void)
+{
+	GRER = GPIO_IRQ_rising_edge & GPIO_IRQ_mask;
+	GFER = GPIO_IRQ_falling_edge & GPIO_IRQ_mask;
+}
+
+static struct syscore_ops sa1100_gpio_syscore_ops = {
+	.suspend	= sa1100_gpio_suspend,
+	.resume		= sa1100_gpio_resume,
+};
+
+static int __init sa1100_gpio_init_devicefs(void)
+{
+	register_syscore_ops(&sa1100_gpio_syscore_ops);
+	return 0;
+}
+
+device_initcall(sa1100_gpio_init_devicefs);
+
 void __init sa1100_init_gpio(void)
 {
+	/* clear all GPIO edge detects */
+	GFER = 0;
+	GRER = 0;
+	GEDR = -1;
+
 	gpiochip_add(&sa1100_gpio_chip);
+
+	sa1100_gpio_irqdomain = irq_domain_add_simple(NULL,
+			28, IRQ_GPIO0,
+			&sa1100_gpio_irqdomain_ops, NULL);
+
+	/*
+	 * Install handlers for GPIO 0-10 edge detect interrupts
+	 */
+	irq_set_chained_handler(IRQ_GPIO0_SC, sa1100_gpio_handler);
+	irq_set_chained_handler(IRQ_GPIO1_SC, sa1100_gpio_handler);
+	irq_set_chained_handler(IRQ_GPIO2_SC, sa1100_gpio_handler);
+	irq_set_chained_handler(IRQ_GPIO3_SC, sa1100_gpio_handler);
+	irq_set_chained_handler(IRQ_GPIO4_SC, sa1100_gpio_handler);
+	irq_set_chained_handler(IRQ_GPIO5_SC, sa1100_gpio_handler);
+	irq_set_chained_handler(IRQ_GPIO6_SC, sa1100_gpio_handler);
+	irq_set_chained_handler(IRQ_GPIO7_SC, sa1100_gpio_handler);
+	irq_set_chained_handler(IRQ_GPIO8_SC, sa1100_gpio_handler);
+	irq_set_chained_handler(IRQ_GPIO9_SC, sa1100_gpio_handler);
+	irq_set_chained_handler(IRQ_GPIO10_SC, sa1100_gpio_handler);
+	/*
+	 * Install handler for GPIO 11-27 edge detect interrupts
+	 */
+	irq_set_chained_handler(IRQ_GPIO11_27, sa1100_gpio_handler);
+
 }