[ARM] pxa: move GPIO IRQ specific code out of irq.c into gpio.c

Signed-off-by: eric miao <eric.miao@marvell.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

1 files changed, 183 insertions, 0 deletions

diff --git a/arch/arm/mach-pxa/gpio.c b/arch/arm/mach-pxa/gpio.c
index 37b5b83fe240..a64227254151 100644
--- a/arch/arm/mach-pxa/gpio.c
+++ b/arch/arm/mach-pxa/gpio.c
@@ -14,6 +14,7 @@
 
 #include <linux/init.h>
 #include <linux/module.h>
+#include <linux/irq.h>
 
 #include <asm/gpio.h>
 #include <asm/hardware.h>
@@ -165,3 +166,185 @@ void __init pxa_init_gpio(int gpio_nr)
                 gpiochip_add(&pxa_gpio_chip[i/32].chip);
         }
 }
+
+/*
+ * PXA GPIO edge detection for IRQs:
+ * IRQs are generated on Falling-Edge, Rising-Edge, or both.
+ * Use this instead of directly setting GRER/GFER.
+ */
+
+static long GPIO_IRQ_rising_edge[4];
+static long GPIO_IRQ_falling_edge[4];
+static long GPIO_IRQ_mask[4];
+
+static int pxa_gpio_irq_type(unsigned int irq, unsigned int type)
+{
+        int gpio, idx;
+
+        gpio = IRQ_TO_GPIO(irq);
+        idx = gpio >> 5;
+
+        if (type == IRQ_TYPE_PROBE) {
+                /* Don't mess with enabled GPIOs using preconfigured edges or
+                 * GPIOs set to alternate function or to output during probe
+                 */
+                if ((GPIO_IRQ_rising_edge[idx] |
+                     GPIO_IRQ_falling_edge[idx] |
+                     GPDR(gpio)) & GPIO_bit(gpio))
+                        return 0;
+                if (GAFR(gpio) & (0x3 << (((gpio) & 0xf)*2)))
+                        return 0;
+                type = IRQ_TYPE_EDGE_RISING | IRQ_TYPE_EDGE_FALLING;
+        }
+
+        pxa_gpio_mode(gpio | GPIO_IN);
+
+        if (type & IRQ_TYPE_EDGE_RISING)
+                __set_bit(gpio, GPIO_IRQ_rising_edge);
+        else
+                __clear_bit(gpio, GPIO_IRQ_rising_edge);
+
+        if (type & IRQ_TYPE_EDGE_FALLING)
+                __set_bit(gpio, GPIO_IRQ_falling_edge);
+        else
+                __clear_bit(gpio, GPIO_IRQ_falling_edge);
+
+        GRER(gpio) = GPIO_IRQ_rising_edge[idx] & GPIO_IRQ_mask[idx];
+        GFER(gpio) = GPIO_IRQ_falling_edge[idx] & GPIO_IRQ_mask[idx];
+
+        pr_debug("%s: IRQ%d (GPIO%d) - edge%s%s\n", __func__, irq, gpio,
+                ((type & IRQ_TYPE_EDGE_RISING)  ? " rising"  : ""),
+                ((type & IRQ_TYPE_EDGE_FALLING) ? " falling" : ""));
+        return 0;
+}
+
+/*
+ * GPIO IRQs must be acknowledged.  This is for GPIO 0 and 1.
+ */
+
+static void pxa_ack_low_gpio(unsigned int irq)
+{
+        GEDR0 = (1 << (irq - IRQ_GPIO0));
+}
+
+static void pxa_mask_low_gpio(unsigned int irq)
+{
+        ICMR &= ~(1 << (irq - PXA_IRQ(0)));
+}
+
+static void pxa_unmask_low_gpio(unsigned int irq)
+{
+        ICMR |= 1 << (irq - PXA_IRQ(0));
+}
+
+static struct irq_chip pxa_low_gpio_chip = {
+        .name           = "GPIO-l",
+        .ack            = pxa_ack_low_gpio,
+        .mask           = pxa_mask_low_gpio,
+        .unmask         = pxa_unmask_low_gpio,
+        .set_type       = pxa_gpio_irq_type,
+};
+
+/*
+ * Demux handler for GPIO>=2 edge detect interrupts
+ */
+
+#define GEDR_BITS       (sizeof(gedr) * BITS_PER_BYTE)
+
+static void pxa_gpio_demux_handler(unsigned int irq, struct irq_desc *desc)
+{
+        int loop, bit, n;
+        unsigned long gedr[4];
+
+        do {
+                gedr[0] = GEDR0 & GPIO_IRQ_mask[0] & ~3;
+                gedr[1] = GEDR1 & GPIO_IRQ_mask[1];
+                gedr[2] = GEDR2 & GPIO_IRQ_mask[2];
+                gedr[3] = GEDR3 & GPIO_IRQ_mask[3];
+
+                GEDR0 = gedr[0]; GEDR1 = gedr[1];
+                GEDR2 = gedr[2]; GEDR3 = gedr[3];
+
+                loop = 0;
+                bit = find_first_bit(gedr, GEDR_BITS);
+                while (bit < GEDR_BITS) {
+                        loop = 1;
+
+                        n = PXA_GPIO_IRQ_BASE + bit;
+                        desc_handle_irq(n, irq_desc + n);
+
+                        bit = find_next_bit(gedr, GEDR_BITS, bit + 1);
+                }
+        } while (loop);
+}
+
+static void pxa_ack_muxed_gpio(unsigned int irq)
+{
+        int gpio = irq - IRQ_GPIO(2) + 2;
+        GEDR(gpio) = GPIO_bit(gpio);
+}
+
+static void pxa_mask_muxed_gpio(unsigned int irq)
+{
+        int gpio = irq - IRQ_GPIO(2) + 2;
+        __clear_bit(gpio, GPIO_IRQ_mask);
+        GRER(gpio) &= ~GPIO_bit(gpio);
+        GFER(gpio) &= ~GPIO_bit(gpio);
+}
+
+static void pxa_unmask_muxed_gpio(unsigned int irq)
+{
+        int gpio = irq - IRQ_GPIO(2) + 2;
+        int idx = gpio >> 5;
+        __set_bit(gpio, GPIO_IRQ_mask);
+        GRER(gpio) = GPIO_IRQ_rising_edge[idx] & GPIO_IRQ_mask[idx];
+        GFER(gpio) = GPIO_IRQ_falling_edge[idx] & GPIO_IRQ_mask[idx];
+}
+
+static struct irq_chip pxa_muxed_gpio_chip = {
+        .name           = "GPIO",
+        .ack            = pxa_ack_muxed_gpio,
+        .mask           = pxa_mask_muxed_gpio,
+        .unmask         = pxa_unmask_muxed_gpio,
+        .set_type       = pxa_gpio_irq_type,
+};
+
+void __init pxa_init_irq_gpio(int gpio_nr)
+{
+        int irq, i;
+
+        pxa_last_gpio = gpio_nr - 1;
+
+        /* clear all GPIO edge detects */
+        for (i = 0; i < gpio_nr; i += 32) {
+                GFER(i) = 0;
+                GRER(i) = 0;
+                GEDR(i) = GEDR(i);
+        }
+
+        /* GPIO 0 and 1 must have their mask bit always set */
+        GPIO_IRQ_mask[0] = 3;
+
+        for (irq = IRQ_GPIO0; irq <= IRQ_GPIO1; irq++) {
+                set_irq_chip(irq, &pxa_low_gpio_chip);
+                set_irq_handler(irq, handle_edge_irq);
+                set_irq_flags(irq, IRQF_VALID | IRQF_PROBE);
+        }
+
+        for (irq = IRQ_GPIO(2); irq < IRQ_GPIO(gpio_nr); irq++) {
+                set_irq_chip(irq, &pxa_muxed_gpio_chip);
+                set_irq_handler(irq, handle_edge_irq);
+                set_irq_flags(irq, IRQF_VALID | IRQF_PROBE);
+        }
+
+        /* Install handler for GPIO>=2 edge detect interrupts */
+        set_irq_chained_handler(IRQ_GPIO_2_x, pxa_gpio_demux_handler);
+
+        pxa_init_gpio(gpio_nr);
+}
+
+void __init pxa_init_gpio_set_wake(int (*set_wake)(unsigned int, unsigned int))
+{
+        pxa_low_gpio_chip.set_wake = set_wake;
+        pxa_muxed_gpio_chip.set_wake = set_wake;
+}