1 files changed, 414 insertions, 0 deletions
diff --git a/arch/arm/mach-at91/gpio.c b/arch/arm/mach-at91/gpio.c
new file mode 100644
index 00000000000..9b7495cd555
--- /dev/null
+++ b/arch/arm/mach-at91/gpio.c
@@ -0,0 +1,414 @@
+/*
+ * linux/arch/arm/mach-at91/gpio.c
+ *
+ * Copyright (C) 2005 HP Labs
+ *
+ * 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.
+ */
+
+#include <linux/clk.h>
+#include <linux/errno.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/kernel.h>
+#include <linux/list.h>
+#include <linux/module.h>
+
+#include <asm/io.h>
+#include <asm/hardware.h>
+#include <asm/arch/at91_pio.h>
+#include <asm/arch/gpio.h>
+
+#include "generic.h"
+
+
+static struct at91_gpio_bank *gpio;
+static int gpio_banks;
+
+
+static inline void __iomem *pin_to_controller(unsigned pin)
+{
+	void __iomem *sys_base = (void __iomem *) AT91_VA_BASE_SYS;
+
+	pin -= PIN_BASE;
+	pin /= 32;
+	if (likely(pin < gpio_banks))
+		return sys_base + gpio[pin].offset;
+
+	return NULL;
+}
+
+static inline unsigned pin_to_mask(unsigned pin)
+{
+	pin -= PIN_BASE;
+	return 1 << (pin % 32);
+}
+
+
+/*--------------------------------------------------------------------------*/
+
+/* Not all hardware capabilities are exposed through these calls; they
+ * only encapsulate the most common features and modes.  (So if you
+ * want to change signals in groups, do it directly.)
+ *
+ * Bootloaders will usually handle some of the pin multiplexing setup.
+ * The intent is certainly that by the time Linux is fully booted, all
+ * pins should have been fully initialized.  These setup calls should
+ * only be used by board setup routines, or possibly in driver probe().
+ *
+ * For bootloaders doing all that setup, these calls could be inlined
+ * as NOPs so Linux won't duplicate any setup code
+ */
+
+
+/*
+ * mux the pin to the "A" internal peripheral role.
+ */
+int __init_or_module at91_set_A_periph(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 + PIO_IDR);
+	__raw_writel(mask, pio + (use_pullup ? PIO_PUER : PIO_PUDR));
+	__raw_writel(mask, pio + PIO_ASR);
+	__raw_writel(mask, pio + PIO_PDR);
+	return 0;
+}
+EXPORT_SYMBOL(at91_set_A_periph);
+
+
+/*
+ * mux the pin to the "B" internal peripheral role.
+ */
+int __init_or_module at91_set_B_periph(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 + PIO_IDR);
+	__raw_writel(mask, pio + (use_pullup ? PIO_PUER : PIO_PUDR));
+	__raw_writel(mask, pio + PIO_BSR);
+	__raw_writel(mask, pio + PIO_PDR);
+	return 0;
+}
+EXPORT_SYMBOL(at91_set_B_periph);
+
+
+/*
+ * mux the pin to the gpio controller (instead of "A" or "B" peripheral), and
+ * configure it for an input.
+ */
+int __init_or_module 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 + PIO_IDR);
+	__raw_writel(mask, pio + (use_pullup ? PIO_PUER : PIO_PUDR));
+	__raw_writel(mask, pio + PIO_ODR);
+	__raw_writel(mask, pio + 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 __init_or_module 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 + PIO_IDR);
+	__raw_writel(mask, pio + PIO_PUDR);
+	__raw_writel(mask, pio + (value ? PIO_SODR : PIO_CODR));
+	__raw_writel(mask, pio + PIO_OER);
+	__raw_writel(mask, pio + PIO_PER);
+	return 0;
+}
+EXPORT_SYMBOL(at91_set_gpio_output);
+
+
+/*
+ * enable/disable the glitch filter; mostly used with IRQ handling.
+ */
+int __init_or_module at91_set_deglitch(unsigned pin, int is_on)
+{
+	void __iomem	*pio = pin_to_controller(pin);
+	unsigned	mask = pin_to_mask(pin);
+
+	if (!pio)
+		return -EINVAL;
+	__raw_writel(mask, pio + (is_on ? PIO_IFER : PIO_IFDR));
+	return 0;
+}
+EXPORT_SYMBOL(at91_set_deglitch);
+
+/*
+ * enable/disable the multi-driver; This is only valid for output and
+ * allows the output pin to run as an open collector output.
+ */
+int __init_or_module at91_set_multi_drive(unsigned pin, int is_on)
+{
+	void __iomem	*pio = pin_to_controller(pin);
+	unsigned	mask = pin_to_mask(pin);
+
+	if (!pio)
+		return -EINVAL;
+
+	__raw_writel(mask, pio + (is_on ? PIO_MDER : PIO_MDDR));
+	return 0;
+}
+EXPORT_SYMBOL(at91_set_multi_drive);
+
+/*--------------------------------------------------------------------------*/
+
+/*
+ * assuming the pin is muxed as a gpio output, set its value.
+ */
+int at91_set_gpio_value(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 + (value ? PIO_SODR : PIO_CODR));
+	return 0;
+}
+EXPORT_SYMBOL(at91_set_gpio_value);
+
+
+/*
+ * read the pin's value (works even if it's not muxed as a gpio).
+ */
+int at91_get_gpio_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 + PIO_PDSR);
+	return (pdsr & mask) != 0;
+}
+EXPORT_SYMBOL(at91_get_gpio_value);
+
+/*--------------------------------------------------------------------------*/
+
+#ifdef CONFIG_PM
+
+static u32 wakeups[MAX_GPIO_BANKS];
+static u32 backups[MAX_GPIO_BANKS];
+
+static int gpio_irq_set_wake(unsigned pin, unsigned state)
+{
+	unsigned	mask = pin_to_mask(pin);
+	unsigned	bank = (pin - PIN_BASE) / 32;
+
+	if (unlikely(bank >= MAX_GPIO_BANKS))
+		return -EINVAL;
+
+	if (state)
+		wakeups[bank] |= mask;
+	else
+		wakeups[bank] &= ~mask;
+
+	set_irq_wake(gpio[bank].id, state);
+
+	return 0;
+}
+
+void at91_gpio_suspend(void)
+{
+	int i;
+
+	for (i = 0; i < gpio_banks; i++) {
+		u32 pio = gpio[i].offset;
+
+		backups[i] = at91_sys_read(pio + PIO_IMR);
+		at91_sys_write(pio + PIO_IDR, backups[i]);
+		at91_sys_write(pio + PIO_IER, wakeups[i]);
+
+		if (!wakeups[i])
+			clk_disable(gpio[i].clock);
+		else {
+#ifdef CONFIG_PM_DEBUG
+			printk(KERN_DEBUG "GPIO-%c may wake for %08x\n", 'A'+i, wakeups[i]);
+#endif
+		}
+	}
+}
+
+void at91_gpio_resume(void)
+{
+	int i;
+
+	for (i = 0; i < gpio_banks; i++) {
+		u32 pio = gpio[i].offset;
+
+		if (!wakeups[i])
+			clk_enable(gpio[i].clock);
+
+		at91_sys_write(pio + PIO_IDR, wakeups[i]);
+		at91_sys_write(pio + PIO_IER, backups[i]);
+	}
+}
+
+#else
+#define gpio_irq_set_wake	NULL
+#endif
+
+
+/* Several AIC controller irqs are dispatched through this GPIO handler.
+ * To use any AT91_PIN_* as an externally triggered IRQ, first call
+ * at91_set_gpio_input() then maybe enable its glitch filter.
+ * Then just request_irq() with the pin ID; it works like any ARM IRQ
+ * handler, though it always triggers on rising and falling edges.
+ *
+ * Alternatively, certain pins may be used directly as IRQ0..IRQ6 after
+ * configuring them with at91_set_a_periph() or at91_set_b_periph().
+ * IRQ0..IRQ6 should be configurable, e.g. level vs edge triggering.
+ */
+
+static void gpio_irq_mask(unsigned pin)
+{
+	void __iomem	*pio = pin_to_controller(pin);
+	unsigned	mask = pin_to_mask(pin);
+
+	if (pio)
+		__raw_writel(mask, pio + PIO_IDR);
+}
+
+static void gpio_irq_unmask(unsigned pin)
+{
+	void __iomem	*pio = pin_to_controller(pin);
+	unsigned	mask = pin_to_mask(pin);
+
+	if (pio)
+		__raw_writel(mask, pio + PIO_IER);
+}
+
+static int gpio_irq_type(unsigned pin, unsigned type)
+{
+	return (type == IRQT_BOTHEDGE) ? 0 : -EINVAL;
+}
+
+static struct irq_chip gpio_irqchip = {
+	.name		= "GPIO",
+	.mask		= gpio_irq_mask,
+	.unmask		= gpio_irq_unmask,
+	.set_type	= gpio_irq_type,
+	.set_wake	= gpio_irq_set_wake,
+};
+
+static void gpio_irq_handler(unsigned irq, struct irq_desc *desc)
+{
+	unsigned	pin;
+	struct irq_desc	*gpio;
+	void __iomem	*pio;
+	u32		isr;
+
+	pio = get_irq_chip_data(irq);
+
+	/* temporarily mask (level sensitive) parent IRQ */
+	desc->chip->ack(irq);
+	for (;;) {
+		/* reading ISR acks the pending (edge triggered) GPIO interrupt */
+		isr = __raw_readl(pio + PIO_ISR) & __raw_readl(pio + PIO_IMR);
+		if (!isr)
+			break;
+
+		pin = (unsigned) get_irq_data(irq);
+		gpio = &irq_desc[pin];
+
+		while (isr) {
+			if (isr & 1) {
+				if (unlikely(gpio->depth)) {
+					/*
+					 * The core ARM interrupt handler lazily disables IRQs so
+					 * another IRQ must be generated before it actually gets
+					 * here to be disabled on the GPIO controller.
+					 */
+					gpio_irq_mask(pin);
+				}
+				else
+					desc_handle_irq(pin, gpio);
+			}
+			pin++;
+			gpio++;
+			isr >>= 1;
+		}
+	}
+	desc->chip->unmask(irq);
+	/* now it may re-trigger */
+}
+
+/*--------------------------------------------------------------------------*/
+
+/*
+ * Called from the processor-specific init to enable GPIO interrupt support.
+ */
+void __init at91_gpio_irq_setup(void)
+{
+	unsigned	pioc, pin;
+
+	for (pioc = 0, pin = PIN_BASE;
+			pioc < gpio_banks;
+			pioc++) {
+		void __iomem	*controller;
+		unsigned	id = gpio[pioc].id;
+		unsigned	i;
+
+		clk_enable(gpio[pioc].clock);	/* enable PIO controller's clock */
+
+		controller = (void __iomem *) AT91_VA_BASE_SYS + gpio[pioc].offset;
+		__raw_writel(~0, controller + PIO_IDR);
+
+		set_irq_data(id, (void *) pin);
+		set_irq_chip_data(id, controller);
+
+		for (i = 0; i < 32; i++, pin++) {
+			/*
+			 * Can use the "simple" and not "edge" handler since it's
+			 * shorter, and the AIC handles interupts sanely.
+			 */
+			set_irq_chip(pin, &gpio_irqchip);
+			set_irq_handler(pin, handle_simple_irq);
+			set_irq_flags(pin, IRQF_VALID);
+		}
+
+		set_irq_chained_handler(id, gpio_irq_handler);
+	}
+	pr_info("AT91: %d gpio irqs in %d banks\n", pin - PIN_BASE, gpio_banks);
+}
+
+/*
+ * Called from the processor-specific init to enable GPIO pin support.
+ */
+void __init at91_gpio_init(struct at91_gpio_bank *data, int nr_banks)
+{
+	BUG_ON(nr_banks > MAX_GPIO_BANKS);
+
+	gpio = data;
+	gpio_banks = nr_banks;
+}