pinctrl: sunxi: Add external interrupts support

The port controller IP found in the Allwinner A10 and A13 can use few of
the pins it manage as an interrupt source, called external interrupts in
the datasheet.

The number of these external interrupts are SoCs specific, but the
current upper limit is 32. In order to work, the external interrupts'
pins have to be muxed to a specific function to generate an interrupt.

This patch adds the irqchip and the needed logic to use the PIO
controller as an interrupt controller.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

1 files changed, 68 insertions, 0 deletions

diff --git a/drivers/pinctrl/pinctrl-sunxi.h b/drivers/pinctrl/pinctrl-sunxi.h
index e921621..d68047d 100644
--- a/drivers/pinctrl/pinctrl-sunxi.h
+++ b/drivers/pinctrl/pinctrl-sunxi.h
@@ -344,9 +344,31 @@
 #define PULL_PINS_BITS		2
 #define PULL_PINS_MASK		0x03
 
+#define SUNXI_IRQ_NUMBER	32
+
+#define IRQ_CFG_REG		0x200
+#define IRQ_CFG_IRQ_PER_REG		8
+#define IRQ_CFG_IRQ_BITS		4
+#define IRQ_CFG_IRQ_MASK		((1 << IRQ_CFG_IRQ_BITS) - 1)
+#define IRQ_CTRL_REG		0x210
+#define IRQ_CTRL_IRQ_PER_REG		32
+#define IRQ_CTRL_IRQ_BITS		1
+#define IRQ_CTRL_IRQ_MASK		((1 << IRQ_CTRL_IRQ_BITS) - 1)
+#define IRQ_STATUS_REG		0x214
+#define IRQ_STATUS_IRQ_PER_REG		32
+#define IRQ_STATUS_IRQ_BITS		1
+#define IRQ_STATUS_IRQ_MASK		((1 << IRQ_STATUS_IRQ_BITS) - 1)
+
+#define IRQ_EDGE_RISING		0x00
+#define IRQ_EDGE_FALLING	0x01
+#define IRQ_LEVEL_HIGH		0x02
+#define IRQ_LEVEL_LOW		0x03
+#define IRQ_EDGE_BOTH		0x04
+
 struct sunxi_desc_function {
 	const char	*name;
 	u8		muxval;
+	u8		irqnum;
 };
 
 struct sunxi_desc_pin {
@@ -378,10 +400,13 @@ struct sunxi_pinctrl {
 	struct gpio_chip		*chip;
 	struct sunxi_pinctrl_desc	*desc;
 	struct device			*dev;
+	struct irq_domain		*domain;
 	struct sunxi_pinctrl_function	*functions;
 	unsigned			nfunctions;
 	struct sunxi_pinctrl_group	*groups;
 	unsigned			ngroups;
+	int				irq;
+	int				irq_array[SUNXI_IRQ_NUMBER];
 	struct pinctrl_dev		*pctl_dev;
 };
 
@@ -398,6 +423,13 @@ struct sunxi_pinctrl {
 		.muxval = _val,					\
 	}
 
+#define SUNXI_FUNCTION_IRQ(_val, _irq)				\
+	{							\
+		.name = "irq",					\
+		.muxval = _val,					\
+		.irqnum = _irq,					\
+	}
+
 /*
  * The sunXi PIO registers are organized as is:
  * 0x00 - 0x0c	Muxing values.
@@ -475,4 +507,40 @@ static inline u32 sunxi_pull_offset(u16 pin)
 	return pin_num * PULL_PINS_BITS;
 }
 
+static inline u32 sunxi_irq_cfg_reg(u16 irq)
+{
+	u8 reg = irq / IRQ_CFG_IRQ_PER_REG;
+	return reg + IRQ_CFG_REG;
+}
+
+static inline u32 sunxi_irq_cfg_offset(u16 irq)
+{
+	u32 irq_num = irq % IRQ_CFG_IRQ_PER_REG;
+	return irq_num * IRQ_CFG_IRQ_BITS;
+}
+
+static inline u32 sunxi_irq_ctrl_reg(u16 irq)
+{
+	u8 reg = irq / IRQ_CTRL_IRQ_PER_REG;
+	return reg + IRQ_CTRL_REG;
+}
+
+static inline u32 sunxi_irq_ctrl_offset(u16 irq)
+{
+	u32 irq_num = irq % IRQ_CTRL_IRQ_PER_REG;
+	return irq_num * IRQ_CTRL_IRQ_BITS;
+}
+
+static inline u32 sunxi_irq_status_reg(u16 irq)
+{
+	u8 reg = irq / IRQ_STATUS_IRQ_PER_REG;
+	return reg + IRQ_STATUS_REG;
+}
+
+static inline u32 sunxi_irq_status_offset(u16 irq)
+{
+	u32 irq_num = irq % IRQ_STATUS_IRQ_PER_REG;
+	return irq_num * IRQ_STATUS_IRQ_BITS;
+}
+
 #endif /* __PINCTRL_SUNXI_H */