From 4f339b429583965a8eb7c23474414d0730db1215 Mon Sep 17 00:00:00 2001 From: popcornmix Date: Wed, 8 Oct 2014 18:50:05 +0100 Subject: [PATCH 002/114] Add bcm2708_gpio driver Signed-off-by: popcornmix bcm2708: Add extension to configure internal pulls The bcm2708 gpio controller supports internal pulls to be used as pull-up, pull-down or being entirely disabled. As it can be useful for a driver to change the pull configuration from it's default pull-down state, add an extension which allows configuring the pull per gpio. Signed-off-by: Julian Scheel bcm2708-gpio: Revert the use of pinctrl_request_gpio In non-DT systems, pinctrl_request_gpio always fails causing "requests probe deferral" messages. In DT systems, it isn't useful because the reference counting is independent of the normal pinctrl pin reservations. gpio: Only clear the currently occurring interrupt. Avoids losing interrupts See: linux #760 bcm2708_gpio: Avoid calling irq_unmask for all interrupts When setting up the interrupts, specify that the handle_simple_irq handler should be used. This leaves interrupt acknowledgement to the caller, and prevents irq_unmask from being called for all interrupts. Issue: linux #760 --- arch/arm/mach-bcm2708/Kconfig | 8 + arch/arm/mach-bcm2708/Makefile | 1 + arch/arm/mach-bcm2708/bcm2708.c | 28 ++ arch/arm/mach-bcm2708/bcm2708_gpio.c | 426 ++++++++++++++++++++++++++++++ arch/arm/mach-bcm2708/include/mach/gpio.h | 17 ++ include/linux/platform_data/bcm2708.h | 23 ++ 6 files changed, 503 insertions(+) create mode 100644 arch/arm/mach-bcm2708/bcm2708_gpio.c create mode 100644 arch/arm/mach-bcm2708/include/mach/gpio.h create mode 100644 include/linux/platform_data/bcm2708.h diff --git a/arch/arm/mach-bcm2708/Kconfig b/arch/arm/mach-bcm2708/Kconfig index 1f11478..9355841 100644 --- a/arch/arm/mach-bcm2708/Kconfig +++ b/arch/arm/mach-bcm2708/Kconfig @@ -9,6 +9,14 @@ config MACH_BCM2708 help Include support for the Broadcom(R) BCM2708 platform. +config BCM2708_GPIO + bool "BCM2708 gpio support" + depends on MACH_BCM2708 + select ARCH_REQUIRE_GPIOLIB + default y + help + Include support for the Broadcom(R) BCM2708 gpio. + config BCM2708_VCMEM bool "Videocore Memory" depends on MACH_BCM2708 diff --git a/arch/arm/mach-bcm2708/Makefile b/arch/arm/mach-bcm2708/Makefile index c76f39bc..a722f3f 100644 --- a/arch/arm/mach-bcm2708/Makefile +++ b/arch/arm/mach-bcm2708/Makefile @@ -3,4 +3,5 @@ # obj-$(CONFIG_MACH_BCM2708) += clock.o bcm2708.o armctrl.o vcio.o power.o dma.o +obj-$(CONFIG_BCM2708_GPIO) += bcm2708_gpio.o obj-$(CONFIG_BCM2708_VCMEM) += vc_mem.o diff --git a/arch/arm/mach-bcm2708/bcm2708.c b/arch/arm/mach-bcm2708/bcm2708.c index 9b4e709..7503649 100644 --- a/arch/arm/mach-bcm2708/bcm2708.c +++ b/arch/arm/mach-bcm2708/bcm2708.c @@ -331,6 +331,31 @@ static struct platform_device bcm2708_vcio_device = { }, }; +#ifdef CONFIG_BCM2708_GPIO +#define BCM_GPIO_DRIVER_NAME "bcm2708_gpio" + +static struct resource bcm2708_gpio_resources[] = { + [0] = { /* general purpose I/O */ + .start = GPIO_BASE, + .end = GPIO_BASE + SZ_4K - 1, + .flags = IORESOURCE_MEM, + }, +}; + +static u64 gpio_dmamask = DMA_BIT_MASK(DMA_MASK_BITS_COMMON); + +static struct platform_device bcm2708_gpio_device = { + .name = BCM_GPIO_DRIVER_NAME, + .id = -1, /* only one VideoCore I/O area */ + .resource = bcm2708_gpio_resources, + .num_resources = ARRAY_SIZE(bcm2708_gpio_resources), + .dev = { + .dma_mask = &gpio_dmamask, + .coherent_dma_mask = DMA_BIT_MASK(DMA_MASK_BITS_COMMON), + }, +}; +#endif + static struct resource bcm2708_systemtimer_resources[] = { [0] = { /* system timer access */ .start = ST_BASE, @@ -473,6 +498,9 @@ void __init bcm2708_init(void) bcm_register_device(&bcm2708_dmaman_device); bcm_register_device(&bcm2708_vcio_device); +#ifdef CONFIG_BCM2708_GPIO + bcm_register_device(&bcm2708_gpio_device); +#endif bcm_register_device(&bcm2708_systemtimer_device); bcm_register_device(&bcm2708_fb_device); bcm_register_device(&bcm2708_usb_device); diff --git a/arch/arm/mach-bcm2708/bcm2708_gpio.c b/arch/arm/mach-bcm2708/bcm2708_gpio.c new file mode 100644 index 0000000..c1e9254 --- /dev/null +++ b/arch/arm/mach-bcm2708/bcm2708_gpio.c @@ -0,0 +1,426 @@ +/* + * linux/arch/arm/mach-bcm2708/bcm2708_gpio.c + * + * Copyright (C) 2010 Broadcom + * + * 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 +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include + +#define BCM_GPIO_DRIVER_NAME "bcm2708_gpio" +#define DRIVER_NAME BCM_GPIO_DRIVER_NAME +#define BCM_GPIO_USE_IRQ 1 + +#define GPIOFSEL(x) (0x00+(x)*4) +#define GPIOSET(x) (0x1c+(x)*4) +#define GPIOCLR(x) (0x28+(x)*4) +#define GPIOLEV(x) (0x34+(x)*4) +#define GPIOEDS(x) (0x40+(x)*4) +#define GPIOREN(x) (0x4c+(x)*4) +#define GPIOFEN(x) (0x58+(x)*4) +#define GPIOHEN(x) (0x64+(x)*4) +#define GPIOLEN(x) (0x70+(x)*4) +#define GPIOAREN(x) (0x7c+(x)*4) +#define GPIOAFEN(x) (0x88+(x)*4) +#define GPIOUD(x) (0x94+(x)*4) +#define GPIOUDCLK(x) (0x98+(x)*4) + +#define GPIO_BANKS 2 + +enum { GPIO_FSEL_INPUT, GPIO_FSEL_OUTPUT, + GPIO_FSEL_ALT5, GPIO_FSEL_ALT_4, + GPIO_FSEL_ALT0, GPIO_FSEL_ALT1, + GPIO_FSEL_ALT2, GPIO_FSEL_ALT3, +}; + + /* Each of the two spinlocks protects a different set of hardware + * regiters and data structurs. This decouples the code of the IRQ from + * the GPIO code. This also makes the case of a GPIO routine call from + * the IRQ code simpler. + */ +static DEFINE_SPINLOCK(lock); /* GPIO registers */ + +struct bcm2708_gpio { + struct list_head list; + void __iomem *base; + struct gpio_chip gc; + unsigned long rising[(BCM2708_NR_GPIOS + 31) / 32]; + unsigned long falling[(BCM2708_NR_GPIOS + 31) / 32]; + unsigned long high[(BCM2708_NR_GPIOS + 31) / 32]; + unsigned long low[(BCM2708_NR_GPIOS + 31) / 32]; +}; + +static int bcm2708_set_function(struct gpio_chip *gc, unsigned offset, + int function) +{ + struct bcm2708_gpio *gpio = container_of(gc, struct bcm2708_gpio, gc); + unsigned long flags; + unsigned gpiodir; + unsigned gpio_bank = offset / 10; + unsigned gpio_field_offset = (offset - 10 * gpio_bank) * 3; + +//printk(KERN_ERR DRIVER_NAME ": bcm2708_gpio_set_function %p (%d,%d)\n", gc, offset, function); + if (offset >= BCM2708_NR_GPIOS) + return -EINVAL; + + spin_lock_irqsave(&lock, flags); + + gpiodir = readl(gpio->base + GPIOFSEL(gpio_bank)); + gpiodir &= ~(7 << gpio_field_offset); + gpiodir |= function << gpio_field_offset; + writel(gpiodir, gpio->base + GPIOFSEL(gpio_bank)); + spin_unlock_irqrestore(&lock, flags); + gpiodir = readl(gpio->base + GPIOFSEL(gpio_bank)); + + return 0; +} + +static int bcm2708_gpio_dir_in(struct gpio_chip *gc, unsigned offset) +{ + return bcm2708_set_function(gc, offset, GPIO_FSEL_INPUT); +} + +static void bcm2708_gpio_set(struct gpio_chip *gc, unsigned offset, int value); +static int bcm2708_gpio_dir_out(struct gpio_chip *gc, unsigned offset, + int value) +{ + int ret; + ret = bcm2708_set_function(gc, offset, GPIO_FSEL_OUTPUT); + if (ret >= 0) + bcm2708_gpio_set(gc, offset, value); + return ret; +} + +static int bcm2708_gpio_get(struct gpio_chip *gc, unsigned offset) +{ + struct bcm2708_gpio *gpio = container_of(gc, struct bcm2708_gpio, gc); + unsigned gpio_bank = offset / 32; + unsigned gpio_field_offset = (offset - 32 * gpio_bank); + unsigned lev; + + if (offset >= BCM2708_NR_GPIOS) + return 0; + lev = readl(gpio->base + GPIOLEV(gpio_bank)); +//printk(KERN_ERR DRIVER_NAME ": bcm2708_gpio_get %p (%d)=%d\n", gc, offset, 0x1 & (lev>>gpio_field_offset)); + return 0x1 & (lev >> gpio_field_offset); +} + +static void bcm2708_gpio_set(struct gpio_chip *gc, unsigned offset, int value) +{ + struct bcm2708_gpio *gpio = container_of(gc, struct bcm2708_gpio, gc); + unsigned gpio_bank = offset / 32; + unsigned gpio_field_offset = (offset - 32 * gpio_bank); +//printk(KERN_ERR DRIVER_NAME ": bcm2708_gpio_set %p (%d=%d)\n", gc, offset, value); + if (offset >= BCM2708_NR_GPIOS) + return; + if (value) + writel(1 << gpio_field_offset, gpio->base + GPIOSET(gpio_bank)); + else + writel(1 << gpio_field_offset, gpio->base + GPIOCLR(gpio_bank)); +} + +/********************** + * extension to configure pullups + */ +int bcm2708_gpio_setpull(struct gpio_chip *gc, unsigned offset, + bcm2708_gpio_pull_t value) +{ + struct bcm2708_gpio *gpio = container_of(gc, struct bcm2708_gpio, gc); + unsigned gpio_bank = offset / 32; + unsigned gpio_field_offset = (offset - 32 * gpio_bank); + + if (offset >= BCM2708_NR_GPIOS) + return -EINVAL; + + switch (value) { + case BCM2708_PULL_UP: + writel(2, gpio->base + GPIOUD(0)); + break; + case BCM2708_PULL_DOWN: + writel(1, gpio->base + GPIOUD(0)); + break; + case BCM2708_PULL_OFF: + writel(0, gpio->base + GPIOUD(0)); + break; + } + + udelay(5); + writel(1 << gpio_field_offset, gpio->base + GPIOUDCLK(gpio_bank)); + udelay(5); + writel(0, gpio->base + GPIOUD(0)); + writel(0 << gpio_field_offset, gpio->base + GPIOUDCLK(gpio_bank)); + + return 0; +} +EXPORT_SYMBOL(bcm2708_gpio_setpull); + +/************************************************************************************************************************* + * bcm2708 GPIO IRQ + */ + +#if BCM_GPIO_USE_IRQ + +static int bcm2708_gpio_to_irq(struct gpio_chip *chip, unsigned gpio) +{ + return gpio_to_irq(gpio); +} + +static int bcm2708_gpio_irq_set_type(struct irq_data *d, unsigned type) +{ + unsigned irq = d->irq; + struct bcm2708_gpio *gpio = irq_get_chip_data(irq); + unsigned gn = irq_to_gpio(irq); + unsigned gb = gn / 32; + unsigned go = gn % 32; + + gpio->rising[gb] &= ~(1 << go); + gpio->falling[gb] &= ~(1 << go); + gpio->high[gb] &= ~(1 << go); + gpio->low[gb] &= ~(1 << go); + + if (type & ~(IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_EDGE_RISING | IRQ_TYPE_LEVEL_LOW | IRQ_TYPE_LEVEL_HIGH)) + return -EINVAL; + + if (type & IRQ_TYPE_EDGE_RISING) + gpio->rising[gb] |= (1 << go); + if (type & IRQ_TYPE_EDGE_FALLING) + gpio->falling[gb] |= (1 << go); + if (type & IRQ_TYPE_LEVEL_HIGH) + gpio->high[gb] |= (1 << go); + if (type & IRQ_TYPE_LEVEL_LOW) + gpio->low[gb] |= (1 << go); + return 0; +} + +static void bcm2708_gpio_irq_mask(struct irq_data *d) +{ + unsigned irq = d->irq; + struct bcm2708_gpio *gpio = irq_get_chip_data(irq); + unsigned gn = irq_to_gpio(irq); + unsigned gb = gn / 32; + unsigned long rising = readl(gpio->base + GPIOREN(gb)); + unsigned long falling = readl(gpio->base + GPIOFEN(gb)); + unsigned long high = readl(gpio->base + GPIOHEN(gb)); + unsigned long low = readl(gpio->base + GPIOLEN(gb)); + + gn = gn % 32; + + writel(rising & ~(1 << gn), gpio->base + GPIOREN(gb)); + writel(falling & ~(1 << gn), gpio->base + GPIOFEN(gb)); + writel(high & ~(1 << gn), gpio->base + GPIOHEN(gb)); + writel(low & ~(1 << gn), gpio->base + GPIOLEN(gb)); +} + +static void bcm2708_gpio_irq_unmask(struct irq_data *d) +{ + unsigned irq = d->irq; + struct bcm2708_gpio *gpio = irq_get_chip_data(irq); + unsigned gn = irq_to_gpio(irq); + unsigned gb = gn / 32; + unsigned go = gn % 32; + unsigned long rising = readl(gpio->base + GPIOREN(gb)); + unsigned long falling = readl(gpio->base + GPIOFEN(gb)); + unsigned long high = readl(gpio->base + GPIOHEN(gb)); + unsigned long low = readl(gpio->base + GPIOLEN(gb)); + + if (gpio->rising[gb] & (1 << go)) { + writel(rising | (1 << go), gpio->base + GPIOREN(gb)); + } else { + writel(rising & ~(1 << go), gpio->base + GPIOREN(gb)); + } + + if (gpio->falling[gb] & (1 << go)) { + writel(falling | (1 << go), gpio->base + GPIOFEN(gb)); + } else { + writel(falling & ~(1 << go), gpio->base + GPIOFEN(gb)); + } + + if (gpio->high[gb] & (1 << go)) { + writel(high | (1 << go), gpio->base + GPIOHEN(gb)); + } else { + writel(high & ~(1 << go), gpio->base + GPIOHEN(gb)); + } + + if (gpio->low[gb] & (1 << go)) { + writel(low | (1 << go), gpio->base + GPIOLEN(gb)); + } else { + writel(low & ~(1 << go), gpio->base + GPIOLEN(gb)); + } +} + +static struct irq_chip bcm2708_irqchip = { + .name = "GPIO", + .irq_enable = bcm2708_gpio_irq_unmask, + .irq_disable = bcm2708_gpio_irq_mask, + .irq_unmask = bcm2708_gpio_irq_unmask, + .irq_mask = bcm2708_gpio_irq_mask, + .irq_set_type = bcm2708_gpio_irq_set_type, +}; + +static irqreturn_t bcm2708_gpio_interrupt(int irq, void *dev_id) +{ + unsigned long edsr; + unsigned bank; + int i; + unsigned gpio; + unsigned level_bits; + struct bcm2708_gpio *gpio_data = dev_id; + + for (bank = 0; bank < GPIO_BANKS; bank++) { + edsr = readl(__io_address(GPIO_BASE) + GPIOEDS(bank)); + level_bits = gpio_data->high[bank] | gpio_data->low[bank]; + + for_each_set_bit(i, &edsr, 32) { + gpio = i + bank * 32; + /* ack edge triggered IRQs immediately */ + if (!(level_bits & (1<gc.to_irq = bcm2708_gpio_to_irq; + + for (irq = GPIO_IRQ_START; irq < (GPIO_IRQ_START + GPIO_IRQS); irq++) { + irq_set_chip_data(irq, ucb); + irq_set_chip_and_handler(irq, &bcm2708_irqchip, + handle_simple_irq); + set_irq_flags(irq, IRQF_VALID); + } + + bcm2708_gpio_irq.dev_id = ucb; + setup_irq(IRQ_GPIO3, &bcm2708_gpio_irq); +} + +#else + +static void bcm2708_gpio_irq_init(struct bcm2708_gpio *ucb) +{ +} + +#endif /* #if BCM_GPIO_USE_IRQ ***************************************************************************************************************** */ + +static int bcm2708_gpio_probe(struct platform_device *dev) +{ + struct bcm2708_gpio *ucb; + struct resource *res; + int bank; + int err = 0; + + printk(KERN_INFO DRIVER_NAME ": bcm2708_gpio_probe %p\n", dev); + + ucb = kzalloc(sizeof(*ucb), GFP_KERNEL); + if (NULL == ucb) { + printk(KERN_ERR DRIVER_NAME ": failed to allocate " + "mailbox memory\n"); + err = -ENOMEM; + goto err; + } + + res = platform_get_resource(dev, IORESOURCE_MEM, 0); + + platform_set_drvdata(dev, ucb); + ucb->base = __io_address(GPIO_BASE); + + ucb->gc.label = "bcm2708_gpio"; + ucb->gc.base = 0; + ucb->gc.ngpio = BCM2708_NR_GPIOS; + ucb->gc.owner = THIS_MODULE; + + ucb->gc.direction_input = bcm2708_gpio_dir_in; + ucb->gc.direction_output = bcm2708_gpio_dir_out; + ucb->gc.get = bcm2708_gpio_get; + ucb->gc.set = bcm2708_gpio_set; + ucb->gc.can_sleep = 0; + + for (bank = 0; bank < GPIO_BANKS; bank++) { + writel(0, ucb->base + GPIOREN(bank)); + writel(0, ucb->base + GPIOFEN(bank)); + writel(0, ucb->base + GPIOHEN(bank)); + writel(0, ucb->base + GPIOLEN(bank)); + writel(0, ucb->base + GPIOAREN(bank)); + writel(0, ucb->base + GPIOAFEN(bank)); + writel(~0, ucb->base + GPIOEDS(bank)); + } + + bcm2708_gpio_irq_init(ucb); + + err = gpiochip_add(&ucb->gc); + +err: + return err; + +} + +static int bcm2708_gpio_remove(struct platform_device *dev) +{ + int err = 0; + struct bcm2708_gpio *ucb = platform_get_drvdata(dev); + + printk(KERN_ERR DRIVER_NAME ": bcm2708_gpio_remove %p\n", dev); + + gpiochip_remove(&ucb->gc); + + platform_set_drvdata(dev, NULL); + kfree(ucb); + + return err; +} + +static struct platform_driver bcm2708_gpio_driver = { + .probe = bcm2708_gpio_probe, + .remove = bcm2708_gpio_remove, + .driver = { + .name = "bcm2708_gpio"}, +}; + +static int __init bcm2708_gpio_init(void) +{ + return platform_driver_register(&bcm2708_gpio_driver); +} + +static void __exit bcm2708_gpio_exit(void) +{ + platform_driver_unregister(&bcm2708_gpio_driver); +} + +module_init(bcm2708_gpio_init); +module_exit(bcm2708_gpio_exit); + +MODULE_DESCRIPTION("Broadcom BCM2708 GPIO driver"); +MODULE_LICENSE("GPL"); diff --git a/arch/arm/mach-bcm2708/include/mach/gpio.h b/arch/arm/mach-bcm2708/include/mach/gpio.h new file mode 100644 index 0000000..7965a97 --- /dev/null +++ b/arch/arm/mach-bcm2708/include/mach/gpio.h @@ -0,0 +1,17 @@ +/* + * arch/arm/mach-bcm2708/include/mach/gpio.h + * + * This file is licensed under the terms of the GNU General Public + * License version 2. This program is licensed "as is" without any + * warranty of any kind, whether express or implied. + */ + +#ifndef __ASM_ARCH_GPIO_H +#define __ASM_ARCH_GPIO_H + +#define BCM2708_NR_GPIOS 54 // number of gpio lines + +#define gpio_to_irq(x) ((x) + GPIO_IRQ_START) +#define irq_to_gpio(x) ((x) - GPIO_IRQ_START) + +#endif diff --git a/include/linux/platform_data/bcm2708.h b/include/linux/platform_data/bcm2708.h new file mode 100644 index 0000000..fb69624 --- /dev/null +++ b/include/linux/platform_data/bcm2708.h @@ -0,0 +1,23 @@ +/* + * include/linux/platform_data/bcm2708.h + * + * 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. + * + * (C) 2014 Julian Scheel + * + */ +#ifndef __BCM2708_H_ +#define __BCM2708_H_ + +typedef enum { + BCM2708_PULL_OFF, + BCM2708_PULL_UP, + BCM2708_PULL_DOWN +} bcm2708_gpio_pull_t; + +extern int bcm2708_gpio_setpull(struct gpio_chip *gc, unsigned offset, + bcm2708_gpio_pull_t value); + +#endif -- 1.8.3.2