GPIO support

adopted Linux gpio code. Implemented for at91sam9. No gpiolib support
yet.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

arch/arm/mach-at91sam9/Makefile

@@ -1,3 +1,2 @@
-obj-y += clocksource.o
-
-
+obj-y += clocksource.o gpio.o
+obj-$(CONFIG_ARCH_AT91SAM9260) += at91sam9260.o

arch/arm/mach-at91sam9/at91sam9260.c

@@ -0,0 +1,26 @@
+#include <common.h>
+#include <gpio.h>
+#include <init.h>
+#include <asm/hardware.h>
+
+static struct at91_gpio_bank at91sam9260_gpio[] = {
+	{
+		.id		= AT91C_ID_PIOA,
+		.regbase	= (void __iomem *)AT91C_BASE_PIOA,
+	}, {
+		.id		= AT91C_ID_PIOB,
+		.regbase	= (void __iomem *)AT91C_BASE_PIOB,
+	}, {
+		.id		= AT91C_ID_PIOC,
+		.regbase	= (void __iomem *)AT91C_BASE_PIOC,
+	}
+};
+
+static int at91sam9260_initialize(unsigned long main_clock)
+{
+	/* Register GPIO subsystem */
+	at91_gpio_init(at91sam9260_gpio, 3);
+	return 0;
+}
+
+core_initcall(at91sam9260_initialize);

arch/arm/mach-at91sam9/gpio.c

@@ -0,0 +1,192 @@
+/*
+ *
+ * (c) 2008 Sascha Hauer, Pengutronix <s.hauer@pengutronix.de>
+ *
+ * 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 <errno.h>
+#include <asm/io.h>
+#include <gpio.h>
+
+#define OFS_PIO_PER	0x00	/* Enable Register */
+#define OFS_PIO_PDR	0x04	/* Disable Register */
+#define OFS_PIO_PSR	0x08	/* Status Register */
+#define OFS_PIO_OER	0x10	/* Output Enable Register */
+#define OFS_PIO_ODR	0x14	/* Output Disable Register */
+#define OFS_PIO_OSR	0x18	/* Output Status Register */
+#define OFS_PIO_IFER	0x20	/* Glitch Input Filter Enable */
+#define OFS_PIO_IFDR	0x24	/* Glitch Input Filter Disable */
+#define OFS_PIO_IFSR	0x28	/* Glitch Input Filter Status */
+#define OFS_PIO_SODR	0x30	/* Set Output Data Register */
+#define OFS_PIO_CODR	0x34	/* Clear Output Data Register */
+#define OFS_PIO_ODSR	0x38	/* Output Data Status Register */
+#define OFS_PIO_PDSR	0x3c	/* Pin Data Status Register */
+#define OFS_PIO_IER	0x40	/* Interrupt Enable Register */
+#define OFS_PIO_IDR	0x44	/* Interrupt Disable Register */
+#define OFS_PIO_IMR	0x48	/* Interrupt Mask Register */
+#define OFS_PIO_ISR	0x4c	/* Interrupt Status Register */
+#define OFS_PIO_MDER	0x50	/* Multi-driver Enable Register */
+#define OFS_PIO_MDDR	0x54	/* Multi-driver Disable Register */
+#define OFS_PIO_MDSR	0x58	/* Multi-driver Status Register */
+#define OFS_PIO_PUDR	0x60	/* Pull-up Disable Register */
+#define OFS_PIO_PUER	0x64	/* Pull-up Enable Register */
+#define OFS_PIO_PUSR	0x68	/* Pull-up Status Register */
+#define OFS_PIO_ASR	0x70	/* Peripheral A Select Register */
+#define OFS_PIO_BSR	0x74	/* Peripheral B Select Register */
+#define OFS_PIO_ABSR	0x78	/* AB Status Register */
+#define OFS_PIO_OWER	0xa0	/* Output Write Enable Register */
+#define OFS_PIO_OWDR	0xa4	/* Output Write Disable Register */
+#define OFS_PIO_OWSR	0xa8	/* Output Write Status Register */
+
+static int gpio_banks;
+static struct at91_gpio_bank *gpio;
+
+static inline void __iomem *pin_to_controller(unsigned pin)
+{
+	pin /= 32;
+	if (likely(pin < gpio_banks))
+		return gpio[pin].regbase;
+
+	return NULL;
+}
+
+static inline unsigned pin_to_mask(unsigned pin)
+{
+	return 1 << (pin % 32);
+}
+
+/*
+ * mux the pin to the gpio controller (instead of "A" or "B" peripheral), and
+ * configure it for an input.
+ */
+int at91_set_gpio_input(unsigned pin, int use_pullup)
+{
+	void __iomem	*pio = pin_to_controller(pin);
+	unsigned	mask = pin_to_mask(pin);
+
+	if (!pio)
+		return -EINVAL;
+
+	__raw_writel(mask, pio + OFS_PIO_IDR);
+	__raw_writel(mask, pio + (use_pullup ? OFS_PIO_PUER : OFS_PIO_PUDR));
+	__raw_writel(mask, pio + OFS_PIO_ODR);
+	__raw_writel(mask, pio + OFS_PIO_PER);
+	return 0;
+}
+EXPORT_SYMBOL(at91_set_gpio_input);
+
+/*
+ * mux the pin to the gpio controller (instead of "A" or "B" peripheral),
+ * and configure it for an output.
+ */
+int at91_set_gpio_output(unsigned pin, int value)
+{
+	void __iomem	*pio = pin_to_controller(pin);
+	unsigned	mask = pin_to_mask(pin);
+
+	if (!pio)
+		return -EINVAL;
+
+	__raw_writel(mask, pio + OFS_PIO_IDR);
+	__raw_writel(mask, pio + OFS_PIO_PUDR);
+	__raw_writel(mask, pio + (value ? OFS_PIO_SODR : OFS_PIO_CODR));
+	__raw_writel(mask, pio + OFS_PIO_OER);
+	__raw_writel(mask, pio + OFS_PIO_PER);
+	return 0;
+}
+EXPORT_SYMBOL(at91_set_gpio_output);
+
+int gpio_direction_input(unsigned pin)
+{
+	void __iomem	*pio = pin_to_controller(pin);
+	unsigned	mask = pin_to_mask(pin);
+
+	if (!pio || !(__raw_readl(pio + OFS_PIO_PSR) & mask))
+		return -EINVAL;
+	__raw_writel(mask, pio + OFS_PIO_ODR);
+	return 0;
+}
+EXPORT_SYMBOL(gpio_direction_input);
+
+int gpio_direction_output(unsigned pin, int value)
+{
+	void __iomem	*pio = pin_to_controller(pin);
+	unsigned	mask = pin_to_mask(pin);
+
+	if (!pio || !(__raw_readl(pio + OFS_PIO_PSR) & mask))
+		return -EINVAL;
+	__raw_writel(mask, pio + (value ? OFS_PIO_SODR : OFS_PIO_CODR));
+	__raw_writel(mask, pio + OFS_PIO_OER);
+	return 0;
+}
+EXPORT_SYMBOL(gpio_direction_output);
+
+/*--------------------------------------------------------------------------*/
+
+/*
+ * assuming the pin is muxed as a gpio output, set its value.
+ */
+void gpio_set_value(unsigned pin, int value)
+{
+	void __iomem	*pio = pin_to_controller(pin);
+	unsigned	mask = pin_to_mask(pin);
+
+	if (!pio)
+		return;
+	__raw_writel(mask, pio + (value ? OFS_PIO_SODR : OFS_PIO_CODR));
+}
+EXPORT_SYMBOL(gpio_set_value);
+
+
+/*
+ * read the pin's value (works even if it's not muxed as a gpio).
+ */
+int gpio_get_value(unsigned pin)
+{
+	void __iomem	*pio = pin_to_controller(pin);
+	unsigned	mask = pin_to_mask(pin);
+	u32		pdsr;
+
+	if (!pio)
+		return -EINVAL;
+	pdsr = __raw_readl(pio + OFS_PIO_PDSR);
+	return (pdsr & mask) != 0;
+}
+EXPORT_SYMBOL(gpio_get_value);
+
+int at91_gpio_init(struct at91_gpio_bank *data, int nr_banks)
+{
+	unsigned		i;
+	struct at91_gpio_bank	*last;
+
+	gpio = data;
+	gpio_banks = nr_banks;
+
+	for (i = 0, last = NULL; i < nr_banks; i++, last = data, data++) {
+		data->chipbase = i * 32;
+
+		/* AT91SAM9263_ID_PIOCDE groups PIOC, PIOD, PIOE */
+		if (last && last->id == data->id)
+			last->next = data;
+	}
+
+	return 0;
+}

include/asm-arm/arch-at91sam9/gpio.h

@@ -0,0 +1,28 @@
+#ifndef __ASM_ARCH_AT91SAM9_GPIO_H
+#define __ASM_ARCH_AT91SAM9_GPIO_H
+
+struct at91_gpio_bank {
+	unsigned chipbase;		/* bank's first GPIO number */
+	void __iomem *regbase;		/* base of register bank */
+	struct at91_gpio_bank *next;	/* bank sharing same IRQ/clock/... */
+	unsigned short id;		/* peripheral ID */
+	unsigned long offset;		/* offset from system peripheral base */
+};
+
+extern int at91_gpio_init(struct at91_gpio_bank *data, int nr_banks);
+
+static inline int gpio_request(unsigned gpio, const char *label)
+{
+	return 0;
+}
+
+static inline void gpio_free(unsigned gpio)
+{
+}
+
+extern int gpio_direction_input(unsigned gpio);
+extern int gpio_direction_output(unsigned gpio, int value);
+extern int gpio_get_value(unsigned gpio);
+extern void gpio_set_value(unsigned gpio, int value);
+
+#endif /* __ASM_ARCH_AT91SAM9_GPIO_H */

include/asm-arm/gpio.h

@@ -0,0 +1,7 @@
+#ifndef _ARCH_ARM_GPIO_H
+#define _ARCH_ARM_GPIO_H
+
+/* not all ARM platforms necessarily support this API ... */
+#include <asm/arch/gpio.h>
+
+#endif /* _ARCH_ARM_GPIO_H */

include/gpio.h

@@ -0,0 +1 @@
+#include <asm/gpio.h>