--- /dev/null
+/*
+ * linux/arch/arm/mach-at91rm9200/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/errno.h>
+#include <linux/kernel.h>
+#include <linux/list.h>
+#include <linux/module.h>
+
+#include <asm/io.h>
+#include <asm/mach/irq.h>
+#include <asm/arch/hardware.h>
+#include <asm/arch/gpio.h>
+
+static const u32 pio_controller_offset[4] = {
+ AT91_PIOA,
+ AT91_PIOB,
+ AT91_PIOC,
+ AT91_PIOD,
+};
+
+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 < BGA_GPIO_BANKS))
+ return sys_base + pio_controller_offset[pin];
+
+ 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);
+
+/*--------------------------------------------------------------------------*/
+
+
+/* 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 irqchip gpio_irqchip = {
+ .mask = gpio_irq_mask,
+ .unmask = gpio_irq_unmask,
+ .set_type = gpio_irq_type,
+};
+
+static void gpio_irq_handler(unsigned irq, struct irqdesc *desc, struct pt_regs *regs)
+{
+ unsigned pin;
+ struct irqdesc *gpio;
+ void __iomem *pio;
+ u32 isr;
+
+ pio = desc->base;
+
+ /* temporarily mask (level sensitive) parent IRQ */
+ desc->chip->ack(irq);
+ for (;;) {
+ isr = __raw_readl(pio + PIO_ISR) & __raw_readl(pio + PIO_IMR);
+ if (!isr)
+ break;
+
+ pin = (unsigned) desc->data;
+ gpio = &irq_desc[pin];
+
+ while (isr) {
+ if (isr & 1) {
+ if (unlikely(gpio->disable_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
+ gpio->handle(pin, gpio, regs);
+ }
+ pin++;
+ gpio++;
+ isr >>= 1;
+ }
+ }
+ desc->chip->unmask(irq);
+ /* now it may re-trigger */
+}
+
+/* call this from board-specific init_irq */
+void __init at91_gpio_irq_setup(unsigned banks)
+{
+ unsigned pioc, pin, id;
+
+ if (banks > 4)
+ banks = 4;
+ for (pioc = 0, pin = PIN_BASE, id = AT91_ID_PIOA;
+ pioc < banks;
+ pioc++, id++) {
+ void __iomem *controller;
+ unsigned i;
+
+ controller = (void __iomem *) AT91_VA_BASE_SYS + pio_controller_offset[pioc];
+ __raw_writel(~0, controller + PIO_IDR);
+
+ set_irq_data(id, (void *) pin);
+ set_irq_chipdata(id, controller);
+
+ for (i = 0; i < 32; i++, pin++) {
+ set_irq_chip(pin, &gpio_irqchip);
+ set_irq_handler(pin, do_simple_IRQ);
+ set_irq_flags(pin, IRQF_VALID);
+ }
+
+ set_irq_chained_handler(id, gpio_irq_handler);
+
+ /* enable the PIO peripheral clock */
+ at91_sys_write(AT91_PMC_PCER, 1 << id);
+ }
+ pr_info("AT91: %d gpio irqs in %d banks\n", pin - PIN_BASE, banks);
+}
git://git.onelab.eu / linux-2.6.git / blobdiff