diff options
Diffstat (limited to 'arch/avr32/mach-at32ap/pio.c')
-rw-r--r-- | arch/avr32/mach-at32ap/pio.c | 470 |
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 00000000..903c7d81 --- /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); +} |