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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /arch/avr32/mach-at32ap/pio.c
Initial import
Diffstat (limited to 'arch/avr32/mach-at32ap/pio.c')
-rw-r--r--arch/avr32/mach-at32ap/pio.c470
1 files changed, 470 insertions, 0 deletions
diff --git a/arch/avr32/mach-at32ap/pio.c b/arch/avr32/mach-at32ap/pio.c
new file mode 100644
index 000000000..903c7d81d
--- /dev/null
+++ b/arch/avr32/mach-at32ap/pio.c
@@ -0,0 +1,470 @@
+/*
+ * Atmel PIO2 Port Multiplexer support
+ *
+ * Copyright (C) 2004-2006 Atmel Corporation
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/clk.h>
+#include <linux/debugfs.h>
+#include <linux/export.h>
+#include <linux/fs.h>
+#include <linux/platform_device.h>
+#include <linux/irq.h>
+
+#include <asm/gpio.h>
+#include <asm/io.h>
+
+#include <mach/portmux.h>
+
+#include "pio.h"
+
+#define MAX_NR_PIO_DEVICES 8
+
+struct pio_device {
+ struct gpio_chip chip;
+ void __iomem *regs;
+ const struct platform_device *pdev;
+ struct clk *clk;
+ u32 pinmux_mask;
+ char name[8];
+};
+
+static struct pio_device pio_dev[MAX_NR_PIO_DEVICES];
+
+static struct pio_device *gpio_to_pio(unsigned int gpio)
+{
+ struct pio_device *pio;
+ unsigned int index;
+
+ index = gpio >> 5;
+ if (index >= MAX_NR_PIO_DEVICES)
+ return NULL;
+ pio = &pio_dev[index];
+ if (!pio->regs)
+ return NULL;
+
+ return pio;
+}
+
+/* Pin multiplexing API */
+static DEFINE_SPINLOCK(pio_lock);
+
+void __init at32_select_periph(unsigned int port, u32 pin_mask,
+ unsigned int periph, unsigned long flags)
+{
+ struct pio_device *pio;
+
+ /* assign and verify pio */
+ pio = gpio_to_pio(port);
+ if (unlikely(!pio)) {
+ printk(KERN_WARNING "pio: invalid port %u\n", port);
+ goto fail;
+ }
+
+ /* Test if any of the requested pins is already muxed */
+ spin_lock(&pio_lock);
+ if (unlikely(pio->pinmux_mask & pin_mask)) {
+ printk(KERN_WARNING "%s: pin(s) busy (requested 0x%x, busy 0x%x)\n",
+ pio->name, pin_mask, pio->pinmux_mask & pin_mask);
+ spin_unlock(&pio_lock);
+ goto fail;
+ }
+
+ pio->pinmux_mask |= pin_mask;
+
+ /* enable pull ups */
+ pio_writel(pio, PUER, pin_mask);
+
+ /* select either peripheral A or B */
+ if (periph)
+ pio_writel(pio, BSR, pin_mask);
+ else
+ pio_writel(pio, ASR, pin_mask);
+
+ /* enable peripheral control */
+ pio_writel(pio, PDR, pin_mask);
+
+ /* Disable pull ups if not requested. */
+ if (!(flags & AT32_GPIOF_PULLUP))
+ pio_writel(pio, PUDR, pin_mask);
+
+ spin_unlock(&pio_lock);
+
+ return;
+
+fail:
+ dump_stack();
+}
+
+void __init at32_select_gpio(unsigned int pin, unsigned long flags)
+{
+ struct pio_device *pio;
+ unsigned int pin_index = pin & 0x1f;
+ u32 mask = 1 << pin_index;
+
+ pio = gpio_to_pio(pin);
+ if (unlikely(!pio)) {
+ printk("pio: invalid pin %u\n", pin);
+ goto fail;
+ }
+
+ if (unlikely(test_and_set_bit(pin_index, &pio->pinmux_mask))) {
+ printk("%s: pin %u is busy\n", pio->name, pin_index);
+ goto fail;
+ }
+
+ if (flags & AT32_GPIOF_OUTPUT) {
+ if (flags & AT32_GPIOF_HIGH)
+ pio_writel(pio, SODR, mask);
+ else
+ pio_writel(pio, CODR, mask);
+ if (flags & AT32_GPIOF_MULTIDRV)
+ pio_writel(pio, MDER, mask);
+ else
+ pio_writel(pio, MDDR, mask);
+ pio_writel(pio, PUDR, mask);
+ pio_writel(pio, OER, mask);
+ } else {
+ if (flags & AT32_GPIOF_PULLUP)
+ pio_writel(pio, PUER, mask);
+ else
+ pio_writel(pio, PUDR, mask);
+ if (flags & AT32_GPIOF_DEGLITCH)
+ pio_writel(pio, IFER, mask);
+ else
+ pio_writel(pio, IFDR, mask);
+ pio_writel(pio, ODR, mask);
+ }
+
+ pio_writel(pio, PER, mask);
+
+ return;
+
+fail:
+ dump_stack();
+}
+
+/*
+ * Undo a previous pin reservation. Will not affect the hardware
+ * configuration.
+ */
+void at32_deselect_pin(unsigned int pin)
+{
+ struct pio_device *pio;
+ unsigned int pin_index = pin & 0x1f;
+
+ pio = gpio_to_pio(pin);
+ if (unlikely(!pio)) {
+ printk("pio: invalid pin %u\n", pin);
+ dump_stack();
+ return;
+ }
+
+ clear_bit(pin_index, &pio->pinmux_mask);
+}
+
+/* Reserve a pin, preventing anyone else from changing its configuration. */
+void __init at32_reserve_pin(unsigned int port, u32 pin_mask)
+{
+ struct pio_device *pio;
+
+ /* assign and verify pio */
+ pio = gpio_to_pio(port);
+ if (unlikely(!pio)) {
+ printk(KERN_WARNING "pio: invalid port %u\n", port);
+ goto fail;
+ }
+
+ /* Test if any of the requested pins is already muxed */
+ spin_lock(&pio_lock);
+ if (unlikely(pio->pinmux_mask & pin_mask)) {
+ printk(KERN_WARNING "%s: pin(s) busy (req. 0x%x, busy 0x%x)\n",
+ pio->name, pin_mask, pio->pinmux_mask & pin_mask);
+ spin_unlock(&pio_lock);
+ goto fail;
+ }
+
+ /* Reserve pins */
+ pio->pinmux_mask |= pin_mask;
+ spin_unlock(&pio_lock);
+ return;
+
+fail:
+ dump_stack();
+}
+
+/*--------------------------------------------------------------------------*/
+
+/* GPIO API */
+
+static int direction_input(struct gpio_chip *chip, unsigned offset)
+{
+ struct pio_device *pio = container_of(chip, struct pio_device, chip);
+ u32 mask = 1 << offset;
+
+ if (!(pio_readl(pio, PSR) & mask))
+ return -EINVAL;
+
+ pio_writel(pio, ODR, mask);
+ return 0;
+}
+
+static int gpio_get(struct gpio_chip *chip, unsigned offset)
+{
+ struct pio_device *pio = container_of(chip, struct pio_device, chip);
+
+ return (pio_readl(pio, PDSR) >> offset) & 1;
+}
+
+static void gpio_set(struct gpio_chip *chip, unsigned offset, int value);
+
+static int direction_output(struct gpio_chip *chip, unsigned offset, int value)
+{
+ struct pio_device *pio = container_of(chip, struct pio_device, chip);
+ u32 mask = 1 << offset;
+
+ if (!(pio_readl(pio, PSR) & mask))
+ return -EINVAL;
+
+ gpio_set(chip, offset, value);
+ pio_writel(pio, OER, mask);
+ return 0;
+}
+
+static void gpio_set(struct gpio_chip *chip, unsigned offset, int value)
+{
+ struct pio_device *pio = container_of(chip, struct pio_device, chip);
+ u32 mask = 1 << offset;
+
+ if (value)
+ pio_writel(pio, SODR, mask);
+ else
+ pio_writel(pio, CODR, mask);
+}
+
+/*--------------------------------------------------------------------------*/
+
+/* GPIO IRQ support */
+
+static void gpio_irq_mask(struct irq_data *d)
+{
+ unsigned gpio = irq_to_gpio(d->irq);
+ struct pio_device *pio = &pio_dev[gpio >> 5];
+
+ pio_writel(pio, IDR, 1 << (gpio & 0x1f));
+}
+
+static void gpio_irq_unmask(struct irq_data *d)
+{
+ unsigned gpio = irq_to_gpio(d->irq);
+ struct pio_device *pio = &pio_dev[gpio >> 5];
+
+ pio_writel(pio, IER, 1 << (gpio & 0x1f));
+}
+
+static int gpio_irq_type(struct irq_data *d, unsigned type)
+{
+ if (type != IRQ_TYPE_EDGE_BOTH && type != IRQ_TYPE_NONE)
+ return -EINVAL;
+
+ return 0;
+}
+
+static struct irq_chip gpio_irqchip = {
+ .name = "gpio",
+ .irq_mask = gpio_irq_mask,
+ .irq_unmask = gpio_irq_unmask,
+ .irq_set_type = gpio_irq_type,
+};
+
+static void gpio_irq_handler(unsigned irq, struct irq_desc *desc)
+{
+ struct pio_device *pio = irq_desc_get_chip_data(desc);
+ unsigned gpio_irq;
+
+ gpio_irq = (unsigned) irq_get_handler_data(irq);
+ for (;;) {
+ u32 isr;
+
+ /* ack pending GPIO interrupts */
+ isr = pio_readl(pio, ISR) & pio_readl(pio, IMR);
+ if (!isr)
+ break;
+ do {
+ int i;
+
+ i = ffs(isr) - 1;
+ isr &= ~(1 << i);
+
+ i += gpio_irq;
+ generic_handle_irq(i);
+ } while (isr);
+ }
+}
+
+static void __init
+gpio_irq_setup(struct pio_device *pio, int irq, int gpio_irq)
+{
+ unsigned i;
+
+ irq_set_chip_data(irq, pio);
+ irq_set_handler_data(irq, (void *)gpio_irq);
+
+ for (i = 0; i < 32; i++, gpio_irq++) {
+ irq_set_chip_data(gpio_irq, pio);
+ irq_set_chip_and_handler(gpio_irq, &gpio_irqchip,
+ handle_simple_irq);
+ }
+
+ irq_set_chained_handler(irq, gpio_irq_handler);
+}
+
+/*--------------------------------------------------------------------------*/
+
+#ifdef CONFIG_DEBUG_FS
+
+#include <linux/seq_file.h>
+
+/*
+ * This shows more info than the generic gpio dump code:
+ * pullups, deglitching, open drain drive.
+ */
+static void pio_bank_show(struct seq_file *s, struct gpio_chip *chip)
+{
+ struct pio_device *pio = container_of(chip, struct pio_device, chip);
+ u32 psr, osr, imr, pdsr, pusr, ifsr, mdsr;
+ unsigned i;
+ u32 mask;
+ char bank;
+
+ psr = pio_readl(pio, PSR);
+ osr = pio_readl(pio, OSR);
+ imr = pio_readl(pio, IMR);
+ pdsr = pio_readl(pio, PDSR);
+ pusr = pio_readl(pio, PUSR);
+ ifsr = pio_readl(pio, IFSR);
+ mdsr = pio_readl(pio, MDSR);
+
+ bank = 'A' + pio->pdev->id;
+
+ for (i = 0, mask = 1; i < 32; i++, mask <<= 1) {
+ const char *label;
+
+ label = gpiochip_is_requested(chip, i);
+ if (!label && (imr & mask))
+ label = "[irq]";
+ if (!label)
+ continue;
+
+ seq_printf(s, " gpio-%-3d P%c%-2d (%-12s) %s %s %s",
+ chip->base + i, bank, i,
+ label,
+ (osr & mask) ? "out" : "in ",
+ (mask & pdsr) ? "hi" : "lo",
+ (mask & pusr) ? " " : "up");
+ if (ifsr & mask)
+ seq_printf(s, " deglitch");
+ if ((osr & mdsr) & mask)
+ seq_printf(s, " open-drain");
+ if (imr & mask)
+ seq_printf(s, " irq-%d edge-both",
+ gpio_to_irq(chip->base + i));
+ seq_printf(s, "\n");
+ }
+}
+
+#else
+#define pio_bank_show NULL
+#endif
+
+
+/*--------------------------------------------------------------------------*/
+
+static int __init pio_probe(struct platform_device *pdev)
+{
+ struct pio_device *pio = NULL;
+ int irq = platform_get_irq(pdev, 0);
+ int gpio_irq_base = GPIO_IRQ_BASE + pdev->id * 32;
+
+ BUG_ON(pdev->id >= MAX_NR_PIO_DEVICES);
+ pio = &pio_dev[pdev->id];
+ BUG_ON(!pio->regs);
+
+ pio->chip.label = pio->name;
+ pio->chip.base = pdev->id * 32;
+ pio->chip.ngpio = 32;
+ pio->chip.dev = &pdev->dev;
+ pio->chip.owner = THIS_MODULE;
+
+ pio->chip.direction_input = direction_input;
+ pio->chip.get = gpio_get;
+ pio->chip.direction_output = direction_output;
+ pio->chip.set = gpio_set;
+ pio->chip.dbg_show = pio_bank_show;
+
+ gpiochip_add(&pio->chip);
+
+ gpio_irq_setup(pio, irq, gpio_irq_base);
+
+ platform_set_drvdata(pdev, pio);
+
+ printk(KERN_DEBUG "%s: base 0x%p, irq %d chains %d..%d\n",
+ pio->name, pio->regs, irq, gpio_irq_base, gpio_irq_base + 31);
+
+ return 0;
+}
+
+static struct platform_driver pio_driver = {
+ .driver = {
+ .name = "pio",
+ },
+};
+
+static int __init pio_init(void)
+{
+ return platform_driver_probe(&pio_driver, pio_probe);
+}
+postcore_initcall(pio_init);
+
+void __init at32_init_pio(struct platform_device *pdev)
+{
+ struct resource *regs;
+ struct pio_device *pio;
+
+ if (pdev->id > MAX_NR_PIO_DEVICES) {
+ dev_err(&pdev->dev, "only %d PIO devices supported\n",
+ MAX_NR_PIO_DEVICES);
+ return;
+ }
+
+ pio = &pio_dev[pdev->id];
+ snprintf(pio->name, sizeof(pio->name), "pio%d", pdev->id);
+
+ regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!regs) {
+ dev_err(&pdev->dev, "no mmio resource defined\n");
+ return;
+ }
+
+ pio->clk = clk_get(&pdev->dev, "mck");
+ if (IS_ERR(pio->clk))
+ /*
+ * This is a fatal error, but if we continue we might
+ * be so lucky that we manage to initialize the
+ * console and display this message...
+ */
+ dev_err(&pdev->dev, "no mck clock defined\n");
+ else
+ clk_enable(pio->clk);
+
+ pio->pdev = pdev;
+ pio->regs = ioremap(regs->start, resource_size(regs));
+
+ /* start with irqs disabled and acked */
+ pio_writel(pio, IDR, ~0UL);
+ (void) pio_readl(pio, ISR);
+}