avr32: Add support for "GPIO" port mux

The "GPIO" port mux is used on AVR32 UC3 parts as well as AT32AP7200 and
all later AVR32 chips. This patch adds a driver for it, implementing the
same API as the existing portmux-pio driver but with more functionality.

Signed-off-by: Haavard Skinnemoen <haavard.skinnemoen@atmel.com>

3 files changed, 301 insertions, 0 deletions

diff --git a/cpu/at32ap/Makefile b/cpu/at32ap/Makefile
index 100cf3e..e08f273 100644
--- a/cpu/at32ap/Makefile
+++ b/cpu/at32ap/Makefile
@@ -35,6 +35,7 @@ COBJS-y			+= exception.o
 COBJS-y			+= cache.o
 COBJS-y			+= interrupts.o
 COBJS-$(CONFIG_PORTMUX_PIO) += portmux-pio.o
+COBJS-$(CONFIG_PORTMUX_GPIO) += portmux-gpio.o
 
 SRCS	:= $(START-y:.o=.S) $(SOBJS-y:.o=.S) $(COBJS-y:.o=.c)
 OBJS	:= $(addprefix $(obj),$(SOBJS-y) $(COBJS-y))
diff --git a/cpu/at32ap/portmux-gpio.c b/cpu/at32ap/portmux-gpio.c
new file mode 100644
index 0000000..9acd040
--- /dev/null
+++ b/cpu/at32ap/portmux-gpio.c
@@ -0,0 +1,107 @@
+/*
+ * Copyright (C) 2008 Atmel Corporation
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ */
+#include <common.h>
+
+#include <asm/io.h>
+#include <asm/arch/memory-map.h>
+#include <asm/arch/gpio.h>
+
+void portmux_select_peripheral(void *port, unsigned long pin_mask,
+		enum portmux_function func, unsigned long flags)
+{
+	/* Both pull-up and pull-down set means buskeeper */
+	if (flags & PORTMUX_PULL_DOWN)
+		gpio_writel(port, PDERS, pin_mask);
+	else
+		gpio_writel(port, PDERC, pin_mask);
+	if (flags & PORTMUX_PULL_UP)
+		gpio_writel(port, PUERS, pin_mask);
+	else
+		gpio_writel(port, PUERC, pin_mask);
+
+	/* Select drive strength */
+	if (flags & PORTMUX_DRIVE_LOW)
+		gpio_writel(port, ODCR0S, pin_mask);
+	else
+		gpio_writel(port, ODCR0C, pin_mask);
+	if (flags & PORTMUX_DRIVE_HIGH)
+		gpio_writel(port, ODCR1S, pin_mask);
+	else
+		gpio_writel(port, ODCR1C, pin_mask);
+
+	/* Select function */
+	if (func & PORTMUX_FUNC_B)
+		gpio_writel(port, PMR0S, pin_mask);
+	else
+		gpio_writel(port, PMR0C, pin_mask);
+	if (func & PORTMUX_FUNC_C)
+		gpio_writel(port, PMR1S, pin_mask);
+	else
+		gpio_writel(port, PMR1C, pin_mask);
+
+	/* Disable GPIO (i.e. enable peripheral) */
+	gpio_writel(port, GPERC, pin_mask);
+}
+
+void portmux_select_gpio(void *port, unsigned long pin_mask,
+		unsigned long flags)
+{
+	/* Both pull-up and pull-down set means buskeeper */
+	if (flags & PORTMUX_PULL_DOWN)
+		gpio_writel(port, PDERS, pin_mask);
+	else
+		gpio_writel(port, PDERC, pin_mask);
+	if (flags & PORTMUX_PULL_UP)
+		gpio_writel(port, PUERS, pin_mask);
+	else
+		gpio_writel(port, PUERC, pin_mask);
+
+	/* Enable open-drain mode if requested */
+	if (flags & PORTMUX_OPEN_DRAIN)
+		gpio_writel(port, ODMERS, pin_mask);
+	else
+		gpio_writel(port, ODMERC, pin_mask);
+
+	/* Select drive strength */
+	if (flags & PORTMUX_DRIVE_LOW)
+		gpio_writel(port, ODCR0S, pin_mask);
+	else
+		gpio_writel(port, ODCR0C, pin_mask);
+	if (flags & PORTMUX_DRIVE_HIGH)
+		gpio_writel(port, ODCR1S, pin_mask);
+	else
+		gpio_writel(port, ODCR1C, pin_mask);
+
+	/* Select direction and initial pin state */
+	if (flags & PORTMUX_DIR_OUTPUT) {
+		if (flags & PORTMUX_INIT_HIGH)
+			gpio_writel(port, OVRS, pin_mask);
+		else
+			gpio_writel(port, OVRC, pin_mask);
+		gpio_writel(port, ODERS, pin_mask);
+	} else {
+		gpio_writel(port, ODERC, pin_mask);
+	}
+
+	/* Enable GPIO */
+	gpio_writel(port, GPERS, pin_mask);
+}
diff --git a/include/asm-avr32/arch-common/portmux-gpio.h b/include/asm-avr32/arch-common/portmux-gpio.h
new file mode 100644
index 0000000..24943ec
--- /dev/null
+++ b/include/asm-avr32/arch-common/portmux-gpio.h
@@ -0,0 +1,193 @@
+/*
+ * Copyright (C) 2008 Atmel Corporation
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ */
+#ifndef __AVR32_PORTMUX_GPIO_H__
+#define __AVR32_PORTMUX_GPIO_H__
+
+#include <asm/io.h>
+
+/* Register offsets */
+struct gpio_regs {
+	u32	GPER;
+	u32	GPERS;
+	u32	GPERC;
+	u32	GPERT;
+	u32	PMR0;
+	u32	PMR0S;
+	u32	PMR0C;
+	u32	PMR0T;
+	u32	PMR1;
+	u32	PMR1S;
+	u32	PMR1C;
+	u32	PMR1T;
+	u32	__reserved0[4];
+	u32	ODER;
+	u32	ODERS;
+	u32	ODERC;
+	u32	ODERT;
+	u32	OVR;
+	u32	OVRS;
+	u32	OVRC;
+	u32	OVRT;
+	u32	PVR;
+	u32	__reserved_PVRS;
+	u32	__reserved_PVRC;
+	u32	__reserved_PVRT;
+	u32	PUER;
+	u32	PUERS;
+	u32	PUERC;
+	u32	PUERT;
+	u32	PDER;
+	u32	PDERS;
+	u32	PDERC;
+	u32	PDERT;
+	u32	IER;
+	u32	IERS;
+	u32	IERC;
+	u32	IERT;
+	u32	IMR0;
+	u32	IMR0S;
+	u32	IMR0C;
+	u32	IMR0T;
+	u32	IMR1;
+	u32	IMR1S;
+	u32	IMR1C;
+	u32	IMR1T;
+	u32	GFER;
+	u32	GFERS;
+	u32	GFERC;
+	u32	GFERT;
+	u32	IFR;
+	u32	__reserved_IFRS;
+	u32	IFRC;
+	u32	__reserved_IFRT;
+	u32	ODMER;
+	u32	ODMERS;
+	u32	ODMERC;
+	u32	ODMERT;
+	u32	__reserved1[4];
+	u32	ODCR0;
+	u32	ODCR0S;
+	u32	ODCR0C;
+	u32	ODCR0T;
+	u32	ODCR1;
+	u32	ODCR1S;
+	u32	ODCR1C;
+	u32	ODCR1T;
+	u32	__reserved2[4];
+	u32	OSRR0;
+	u32	OSRR0S;
+	u32	OSRR0C;
+	u32	OSRR0T;
+	u32	__reserved3[8];
+	u32	STER;
+	u32	STERS;
+	u32	STERC;
+	u32	STERT;
+	u32	__reserved4[35];
+	u32	VERSION;
+};
+
+/* Register access macros */
+#define gpio_readl(port, reg)						\
+	__raw_readl(&((struct gpio_regs *)port)->reg)
+#define gpio_writel(gpio, reg, value)					\
+	__raw_writel(value, &((struct gpio_regs *)port)->reg)
+
+/* Portmux API starts here. See doc/README.AVR32-port-muxing */
+
+enum portmux_function {
+	PORTMUX_FUNC_A,
+	PORTMUX_FUNC_B,
+	PORTMUX_FUNC_C,
+	PORTMUX_FUNC_D,
+};
+
+#define PORTMUX_DIR_INPUT	(0 << 0)
+#define PORTMUX_DIR_OUTPUT	(1 << 0)
+#define PORTMUX_INIT_LOW	(0 << 1)
+#define PORTMUX_INIT_HIGH	(1 << 1)
+#define PORTMUX_PULL_UP		(1 << 2)
+#define PORTMUX_PULL_DOWN	(2 << 2)
+#define PORTMUX_BUSKEEPER	(3 << 2)
+#define PORTMUX_DRIVE_MIN	(0 << 4)
+#define PORTMUX_DRIVE_LOW	(1 << 4)
+#define PORTMUX_DRIVE_HIGH	(2 << 4)
+#define PORTMUX_DRIVE_MAX	(3 << 4)
+#define PORTMUX_OPEN_DRAIN	(1 << 6)
+
+void portmux_select_peripheral(void *port, unsigned long pin_mask,
+		enum portmux_function func, unsigned long flags);
+void portmux_select_gpio(void *port, unsigned long pin_mask,
+		unsigned long flags);
+
+/* Internal helper functions */
+
+static inline void *gpio_pin_to_port(unsigned int pin)
+{
+	return (void *)GPIO_BASE + (pin >> 5) * 0x200;
+}
+
+static inline void __gpio_set_output_value(void *port, unsigned int pin,
+		int value)
+{
+	if (value)
+		gpio_writel(port, OVRS, 1 << pin);
+	else
+		gpio_writel(port, OVRC, 1 << pin);
+}
+
+static inline int __gpio_get_input_value(void *port, unsigned int pin)
+{
+	return (gpio_readl(port, PVR) >> pin) & 1;
+}
+
+void gpio_set_output_value(unsigned int pin, int value);
+int gpio_get_input_value(unsigned int pin);
+
+/* GPIO API starts here */
+
+/*
+ * GCC doesn't realize that the constant case is extremely trivial,
+ * so we need to help it make the right decision by using
+ * always_inline.
+ */
+__attribute__((always_inline))
+static inline void gpio_set_value(unsigned int pin, int value)
+{
+	if (__builtin_constant_p(pin))
+		__gpio_set_output_value(gpio_pin_to_port(pin),
+				pin & 0x1f, value);
+	else
+		gpio_set_output_value(pin, value);
+}
+
+__attribute__((always_inline))
+static inline int gpio_get_value(unsigned int pin)
+{
+	if (__builtin_constant_p(pin))
+		return __gpio_get_input_value(gpio_pin_to_port(pin),
+				pin & 0x1f);
+	else
+		return gpio_get_input_value(pin);
+}
+
+#endif /* __AVR32_PORTMUX_GPIO_H__ */