[PATCH-V2] mpc8xxx_gpio: add interrupt support
Peter Korsgaard
jacmet at sunsite.dk
Mon Dec 21 23:26:15 EST 2009
Signed-off-by: Peter Korsgaard <jacmet at sunsite.dk>
---
.../powerpc/dts-bindings/fsl/8xxx_gpio.txt | 22 +++-
arch/powerpc/sysdev/mpc8xxx_gpio.c | 147 ++++++++++++++++++++
2 files changed, 168 insertions(+), 1 deletions(-)
Changes since v1:
- Document OF binding for IRQ as requested by Kumar.
diff --git a/Documentation/powerpc/dts-bindings/fsl/8xxx_gpio.txt b/Documentation/powerpc/dts-bindings/fsl/8xxx_gpio.txt
index d015dce..b0019eb 100644
--- a/Documentation/powerpc/dts-bindings/fsl/8xxx_gpio.txt
+++ b/Documentation/powerpc/dts-bindings/fsl/8xxx_gpio.txt
@@ -11,7 +11,7 @@ Required properties:
83xx, "fsl,mpc8572-gpio" for 85xx and "fsl,mpc8610-gpio" for 86xx.
- #gpio-cells : Should be two. The first cell is the pin number and the
second cell is used to specify optional parameters (currently unused).
- - interrupts : Interrupt mapping for GPIO IRQ (currently unused).
+ - interrupts : Interrupt mapping for GPIO IRQ.
- interrupt-parent : Phandle for the interrupt controller that
services interrupts for this device.
- gpio-controller : Marks the port as GPIO controller.
@@ -38,3 +38,23 @@ Example of gpio-controller nodes for a MPC8347 SoC:
See booting-without-of.txt for details of how to specify GPIO
information for devices.
+
+To use GPIO pins as interrupt sources for peripherals, specify the
+GPIO controller as the interrupt parent and define GPIO number +
+trigger mode using the interrupts property, which is defined like
+this:
+
+interrupts = <number trigger>, where:
+ - number: GPIO pin (0..31)
+ - trigger: trigger mode:
+ 2 = trigger on falling edge
+ 3 = trigger on both edges
+
+Example of device using this is:
+
+ funkyfpga at 0 {
+ compatible = "funky-fpga";
+ ...
+ interrupts = <4 3>;
+ interrupt-parent = <&gpio1>;
+ };
diff --git a/arch/powerpc/sysdev/mpc8xxx_gpio.c b/arch/powerpc/sysdev/mpc8xxx_gpio.c
index ee1c0e1..b4f861a 100644
--- a/arch/powerpc/sysdev/mpc8xxx_gpio.c
+++ b/arch/powerpc/sysdev/mpc8xxx_gpio.c
@@ -15,6 +15,7 @@
#include <linux/of.h>
#include <linux/of_gpio.h>
#include <linux/gpio.h>
+#include <linux/irq.h>
#define MPC8XXX_GPIO_PINS 32
@@ -34,6 +35,7 @@ struct mpc8xxx_gpio_chip {
* open drain mode safely
*/
u32 data;
+ struct irq_host *irq;
};
static inline u32 mpc8xxx_gpio2mask(unsigned int gpio)
@@ -127,12 +129,136 @@ static int mpc8xxx_gpio_dir_out(struct gpio_chip *gc, unsigned int gpio, int val
return 0;
}
+static int mpc8xxx_gpio_to_irq(struct gpio_chip *gc, unsigned offset)
+{
+ struct of_mm_gpio_chip *mm = to_of_mm_gpio_chip(gc);
+ struct mpc8xxx_gpio_chip *mpc8xxx_gc = to_mpc8xxx_gpio_chip(mm);
+
+ if (mpc8xxx_gc->irq && offset < MPC8XXX_GPIO_PINS)
+ return irq_create_mapping(mpc8xxx_gc->irq, offset);
+ else
+ return -ENXIO;
+}
+
+static void mpc8xxx_gpio_irq_cascade(unsigned int irq, struct irq_desc *desc)
+{
+ struct mpc8xxx_gpio_chip *mpc8xxx_gc = get_irq_desc_data(desc);
+ struct of_mm_gpio_chip *mm = &mpc8xxx_gc->mm_gc;
+ unsigned int mask;
+
+ mask = in_be32(mm->regs + GPIO_IER) & in_be32(mm->regs + GPIO_IMR);
+ if (mask)
+ generic_handle_irq(irq_linear_revmap(mpc8xxx_gc->irq,
+ 32 - ffs(mask)));
+}
+
+static void mpc8xxx_irq_unmask(unsigned int virq)
+{
+ struct mpc8xxx_gpio_chip *mpc8xxx_gc = get_irq_chip_data(virq);
+ struct of_mm_gpio_chip *mm = &mpc8xxx_gc->mm_gc;
+ unsigned long flags;
+
+ spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
+
+ setbits32(mm->regs + GPIO_IMR, mpc8xxx_gpio2mask(virq_to_hw(virq)));
+
+ spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
+}
+
+static void mpc8xxx_irq_mask(unsigned int virq)
+{
+ struct mpc8xxx_gpio_chip *mpc8xxx_gc = get_irq_chip_data(virq);
+ struct of_mm_gpio_chip *mm = &mpc8xxx_gc->mm_gc;
+ unsigned long flags;
+
+ spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
+
+ clrbits32(mm->regs + GPIO_IMR, mpc8xxx_gpio2mask(virq_to_hw(virq)));
+
+ spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
+}
+
+static void mpc8xxx_irq_ack(unsigned int virq)
+{
+ struct mpc8xxx_gpio_chip *mpc8xxx_gc = get_irq_chip_data(virq);
+ struct of_mm_gpio_chip *mm = &mpc8xxx_gc->mm_gc;
+
+ out_be32(mm->regs + GPIO_IER, mpc8xxx_gpio2mask(virq_to_hw(virq)));
+}
+
+static int mpc8xxx_irq_set_type(unsigned int virq, unsigned int flow_type)
+{
+ struct mpc8xxx_gpio_chip *mpc8xxx_gc = get_irq_chip_data(virq);
+ struct of_mm_gpio_chip *mm = &mpc8xxx_gc->mm_gc;
+ unsigned long flags;
+
+ switch (flow_type) {
+ case IRQ_TYPE_EDGE_FALLING:
+ spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
+ setbits32(mm->regs + GPIO_ICR,
+ mpc8xxx_gpio2mask(virq_to_hw(virq)));
+ spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
+ break;
+
+ case IRQ_TYPE_EDGE_BOTH:
+ spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
+ clrbits32(mm->regs + GPIO_ICR,
+ mpc8xxx_gpio2mask(virq_to_hw(virq)));
+ spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
+ break;
+
+ default:
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static struct irq_chip mpc8xxx_irq_chip = {
+ .name = "mpc8xxx-gpio",
+ .unmask = mpc8xxx_irq_unmask,
+ .mask = mpc8xxx_irq_mask,
+ .ack = mpc8xxx_irq_ack,
+ .set_type = mpc8xxx_irq_set_type,
+};
+
+static int mpc8xxx_gpio_irq_map(struct irq_host *h, unsigned int virq,
+ irq_hw_number_t hw)
+{
+ set_irq_chip_data(virq, h->host_data);
+ set_irq_chip_and_handler(virq, &mpc8xxx_irq_chip, handle_level_irq);
+ set_irq_type(virq, IRQ_TYPE_NONE);
+
+ return 0;
+}
+
+static int mpc8xxx_gpio_irq_xlate(struct irq_host *h, struct device_node *ct,
+ u32 *intspec, unsigned int intsize,
+ irq_hw_number_t *out_hwirq,
+ unsigned int *out_flags)
+
+{
+ /* interrupt sense values coming from the device tree equal either
+ * EDGE_FALLING or EDGE_BOTH
+ */
+ *out_hwirq = intspec[0];
+ *out_flags = intspec[1];
+
+ return 0;
+}
+
+static struct irq_host_ops mpc8xxx_gpio_irq_ops = {
+ .map = mpc8xxx_gpio_irq_map,
+ .xlate = mpc8xxx_gpio_irq_xlate,
+};
+
static void __init mpc8xxx_add_controller(struct device_node *np)
{
struct mpc8xxx_gpio_chip *mpc8xxx_gc;
struct of_mm_gpio_chip *mm_gc;
struct of_gpio_chip *of_gc;
struct gpio_chip *gc;
+ unsigned hwirq;
int ret;
mpc8xxx_gc = kzalloc(sizeof(*mpc8xxx_gc), GFP_KERNEL);
@@ -157,11 +283,32 @@ static void __init mpc8xxx_add_controller(struct device_node *np)
else
gc->get = mpc8xxx_gpio_get;
gc->set = mpc8xxx_gpio_set;
+ gc->to_irq = mpc8xxx_gpio_to_irq;
ret = of_mm_gpiochip_add(np, mm_gc);
if (ret)
goto err;
+ hwirq = irq_of_parse_and_map(np, 0);
+ if (hwirq == NO_IRQ)
+ goto skip_irq;
+
+ mpc8xxx_gc->irq =
+ irq_alloc_host(np, IRQ_HOST_MAP_LINEAR, MPC8XXX_GPIO_PINS,
+ &mpc8xxx_gpio_irq_ops, MPC8XXX_GPIO_PINS);
+ if (!mpc8xxx_gc->irq)
+ goto skip_irq;
+
+ mpc8xxx_gc->irq->host_data = mpc8xxx_gc;
+
+ /* ack and mask all irqs */
+ out_be32(mm_gc->regs + GPIO_IER, 0xffffffff);
+ out_be32(mm_gc->regs + GPIO_IMR, 0);
+
+ set_irq_data(hwirq, mpc8xxx_gc);
+ set_irq_chained_handler(hwirq, mpc8xxx_gpio_irq_cascade);
+
+skip_irq:
return;
err:
--
1.6.5
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