avr32: refactor the portmux/gpio code

  - Separate the portmux configuration functionality from the GPIO pin
    control API.
  - Separate the controller-specific code from the chip-specific code.
  - Allow "ganged" port configuration (multiple pins at once).
  - Add more flexibility to the "canned" peripheral select functions:
      - Allow using more than 23 address bits, more chip selects, as
	well as NAND- and CF-specific pins.
      - Make the MACB SPEED pin optional, and choose between MII/RMII
	using a parameter instead of an #ifdef.
      - Make it possible to use other MMC slots than slot 0, and support
	different MMC/SDCard data bus widths.
  - Use more reasonable pull-up defaults; floating pins may consume a
    lot of power.
  - Get rid of some custom portmux code from the mimc200 board code. The
    old gpio/portmux API couldn't really handle its requirements, but
    the new one can.
  - Add documentation.

The end result is slightly smaller code for all boards. Which isn't
really the point, but at least it isn't any larger.

This has been verified on ATSTK1002 and ATNGW100. I'd appreciate if
the board maintainers could help me test this on their boards. In
particular, the mimc200 port has lost a lot of code, so I'm hoping Mark
can help me out.

Signed-off-by: Haavard Skinnemoen <haavard.skinnemoen@atmel.com>
Cc: Hans-Christian Egtvedt <hans-christian.egtvedt@atmel.com>
Cc: Mark Jackson <mpfj@mimc.co.uk>
Cc: Alex Raimondi <alex.raimondi@miromico.ch>
Cc: Julien May <julien.may@miromico.ch>

Changes since v1:
  * Enable pullup on NWAIT
  * Add missing include to portmux-pio.h
  * Rename CONFIG_PIO2 -> CONFIG_PORTMUX_PIO to match docs
diff --git a/include/asm-avr32/arch-common/portmux-pio.h b/include/asm-avr32/arch-common/portmux-pio.h
new file mode 100644
index 0000000..1abe5be
--- /dev/null
+++ b/include/asm-avr32/arch-common/portmux-pio.h
@@ -0,0 +1,138 @@
+/*
+ * Copyright (C) 2006, 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_PIO_H__
+#define __AVR32_PORTMUX_PIO_H__
+
+#include <asm/io.h>
+
+/* PIO register offsets */
+#define PIO_PER			0x0000
+#define PIO_PDR			0x0004
+#define PIO_PSR			0x0008
+#define PIO_OER			0x0010
+#define PIO_ODR			0x0014
+#define PIO_OSR			0x0018
+#define PIO_IFER		0x0020
+#define PIO_IFDR		0x0024
+#define PIO_ISFR		0x0028
+#define PIO_SODR		0x0030
+#define PIO_CODR		0x0034
+#define PIO_ODSR		0x0038
+#define PIO_PDSR		0x003c
+#define PIO_IER			0x0040
+#define PIO_IDR			0x0044
+#define PIO_IMR			0x0048
+#define PIO_ISR			0x004c
+#define PIO_MDER		0x0050
+#define PIO_MDDR		0x0054
+#define PIO_MDSR		0x0058
+#define PIO_PUDR		0x0060
+#define PIO_PUER		0x0064
+#define PIO_PUSR		0x0068
+#define PIO_ASR			0x0070
+#define PIO_BSR			0x0074
+#define PIO_ABSR		0x0078
+#define PIO_OWER		0x00a0
+#define PIO_OWDR		0x00a4
+#define PIO_OWSR		0x00a8
+
+/* Hardware register access */
+#define pio_readl(base, reg)				\
+	__raw_readl((void *)base + PIO_##reg)
+#define pio_writel(base, reg, value)			\
+	__raw_writel((value), (void *)base + PIO_##reg)
+
+/* Portmux API starts here. See doc/README.AVR32-port-muxing */
+
+enum portmux_function {
+	PORTMUX_FUNC_A,
+	PORTMUX_FUNC_B,
+};
+
+/* Pull-down, buskeeper and drive strength are not supported */
+#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	(0)
+#define PORTMUX_BUSKEEPER	PORTMUX_PULL_UP
+#define PORTMUX_DRIVE_MIN	(0)
+#define PORTMUX_DRIVE_LOW	(0)
+#define PORTMUX_DRIVE_HIGH	(0)
+#define PORTMUX_DRIVE_MAX	(0)
+#define PORTMUX_OPEN_DRAIN	(1 << 3)
+
+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 __pio_set_output_value(void *port, unsigned int pin,
+		int value)
+{
+	/*
+	 * value will usually be constant, but it's pretty cheap
+	 * either way.
+	 */
+	if (value)
+		pio_writel(port, SODR, 1 << pin);
+	else
+		pio_writel(port, CODR, 1 << pin);
+}
+
+static inline int __pio_get_input_value(void *port, unsigned int pin)
+{
+	return (pio_readl(port, PDSR) >> pin) & 1;
+}
+
+void pio_set_output_value(unsigned int pin, int value);
+int pio_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))
+		__pio_set_output_value(pio_pin_to_port(pin), pin & 0x1f, value);
+	else
+		pio_set_output_value(pin, value);
+}
+
+__attribute__((always_inline))
+static inline int gpio_get_value(unsigned int pin)
+{
+	if (__builtin_constant_p(pin))
+		return __pio_get_input_value(pio_pin_to_port(pin), pin & 0x1f);
+	else
+		return pio_get_input_value(pin);
+}
+
+#endif /* __AVR32_PORTMUX_PIO_H__ */