From: Tien Hock Loh <thloh@xxxxxxxxxx> Add driver support for Altera GPIO soft IP, including interrupts and I/O. Tested on Altera CV SoC board using dipsw and LED using LED framework. Signed-off-by: Tien Hock Loh <thloh@xxxxxxxxxx> --- .../devicetree/bindings/gpio/gpio-altera.txt | 35 ++ drivers/gpio/Kconfig | 7 + drivers/gpio/Makefile | 1 + drivers/gpio/gpio-altera.c | 395 +++++++++++++++++++++ 4 files changed, 438 insertions(+) create mode 100644 Documentation/devicetree/bindings/gpio/gpio-altera.txt create mode 100644 drivers/gpio/gpio-altera.c diff --git a/Documentation/devicetree/bindings/gpio/gpio-altera.txt b/Documentation/devicetree/bindings/gpio/gpio-altera.txt new file mode 100644 index 0000000..6c57d84 --- /dev/null +++ b/Documentation/devicetree/bindings/gpio/gpio-altera.txt @@ -0,0 +1,35 @@ +Altera GPIO controller bindings + +Required properties: +- compatible: + - "altr,pio-1.0" +- reg: Physical base address and length of the controller's registers. +- #gpio-cells : Should be 1 + - first cell is the gpio offset number +- gpio-controller : Marks the device node as a GPIO controller. +- #interrupt-cells : Should be 1. +- interrupts: Specify the interrupt. +- interrupt-controller: Mark the device node as an interrupt controller + The first cell is the local interrupt offset number to the GPIO controller. + +Altera GPIO specific properties: +- altr,gpio-bank-width: Width of the GPIO bank. This defines how many pins the + GPIO device has. Ranges between 1-32. +- altr,interrupt_trigger: Specifies the interrupt trigger type the GPIO + hardware is synthesized. This field is required if the Altera GPIO controller + used has IRQ enabled as the interrupt type is not software controlled, + but hardware synthesized. + +Example: + +gpio_altr: gpio_altr { + compatible = "altr,pio-1.0"; + reg = <0xff200000 0x10>; + interrupts = <0 45 4>; + altr,gpio-bank-width = <32>; + altr,interrupt_trigger = <0>; + #gpio-cells = <1>; + gpio-controller; + #interrupt-cells = <1>; + interrupt-controller; +}; diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig index 0f04444..acd67de 100644 --- a/drivers/gpio/Kconfig +++ b/drivers/gpio/Kconfig @@ -121,6 +121,13 @@ config GPIO_GENERIC_PLATFORM help Say yes here to support basic platform_device memory-mapped GPIO controllers. +config GPIO_ALTERA + tristate "Altera GPIO" + select IRQ_DOMAIN + depends on OF_GPIO + help + Say yes here to support the Altera PIO device. + config GPIO_IT8761E tristate "IT8761E GPIO support" depends on X86 # unconditional access to IO space. diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile index 7971e36..a326fd2 100644 --- a/drivers/gpio/Makefile +++ b/drivers/gpio/Makefile @@ -14,6 +14,7 @@ obj-$(CONFIG_GPIO_74X164) += gpio-74x164.o obj-$(CONFIG_GPIO_ADNP) += gpio-adnp.o obj-$(CONFIG_GPIO_ADP5520) += gpio-adp5520.o obj-$(CONFIG_GPIO_ADP5588) += gpio-adp5588.o +obj-$(CONFIG_GPIO_ALTERA) += gpio-altera.o obj-$(CONFIG_GPIO_AMD8111) += gpio-amd8111.o obj-$(CONFIG_GPIO_ARIZONA) += gpio-arizona.o obj-$(CONFIG_GPIO_BCM_KONA) += gpio-bcm-kona.o diff --git a/drivers/gpio/gpio-altera.c b/drivers/gpio/gpio-altera.c new file mode 100644 index 0000000..9f4de82 --- /dev/null +++ b/drivers/gpio/gpio-altera.c @@ -0,0 +1,395 @@ +/* + * Copyright (C) 2013 Altera Corporation + * Based on gpio-mpc8xxx.c + * + * 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. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see <http://www.gnu.org/licenses/>. + */ + +#include <linux/gpio.h> +#include <linux/kernel.h> +#include <linux/slab.h> +#include <linux/module.h> +#include <linux/io.h> +#include <linux/irq.h> +#include <linux/of_irq.h> +#include <linux/irqdomain.h> +#include <linux/interrupt.h> +#include <linux/of_gpio.h> +#include <linux/platform_device.h> + +#define ALTERA_GPIO_DATA 0x0 +#define ALTERA_GPIO_DIR 0x4 +#define ALTERA_GPIO_IRQ_MASK 0x8 +#define ALTERA_GPIO_EDGE_CAP 0xc +#define ALTERA_GPIO_OUTSET 0x10 +#define ALTERA_GPIO_OUTCLEAR 0x14 + +/** +* struct altera_gpio_chip +* @mmchip : memory mapped chip structure. +* @irq : irq domain that this driver is registered to. +* @gpio_lock : synchronization lock so that new irq/set/get requests + will be blocked until the current one completes. +* @interrupt_trigger : specifies the hardware configured IRQ trigger type + (rising, falling, both, high) +* @mapped_irq : kernel mapped irq number. +*/ +struct altera_gpio_chip { + struct of_mm_gpio_chip mmchip; + struct irq_domain *irq; + spinlock_t gpio_lock; + int interrupt_trigger; + int edge_type; + int mapped_irq; +}; + +static void altera_gpio_irq_unmask(struct irq_data *d) +{ + struct altera_gpio_chip *altera_gc = irq_data_get_irq_chip_data(d); + struct of_mm_gpio_chip *mm_gc = &altera_gc->mmchip; + unsigned long flags; + unsigned int intmask; + + spin_lock_irqsave(&altera_gc->gpio_lock, flags); + intmask = readl(mm_gc->regs + ALTERA_GPIO_IRQ_MASK); + /* Set ALTERA_GPIO_IRQ_MASK bit to unmask */ + intmask |= BIT(irqd_to_hwirq(d)); + writel(intmask, mm_gc->regs + ALTERA_GPIO_IRQ_MASK); + spin_unlock_irqrestore(&altera_gc->gpio_lock, flags); +} + +static void altera_gpio_irq_mask(struct irq_data *d) +{ + struct altera_gpio_chip *altera_gc = irq_data_get_irq_chip_data(d); + struct of_mm_gpio_chip *mm_gc = &altera_gc->mmchip; + unsigned long flags; + unsigned int intmask; + + spin_lock_irqsave(&altera_gc->gpio_lock, flags); + intmask = readl(mm_gc->regs + ALTERA_GPIO_IRQ_MASK); + /* Clear ALTERA_GPIO_IRQ_MASK bit to mask */ + intmask &= ~BIT(irqd_to_hwirq(d)); + writel(intmask, mm_gc->regs + ALTERA_GPIO_IRQ_MASK); + spin_unlock_irqrestore(&altera_gc->gpio_lock, flags); +} + +static int altera_gpio_irq_set_type(struct irq_data *d, + unsigned int type) +{ + struct altera_gpio_chip *altera_gc = irq_data_get_irq_chip_data(d); + + if (type == IRQ_TYPE_NONE) + return 0; + + if (type == IRQ_TYPE_LEVEL_HIGH && + altera_gc->interrupt_trigger == IRQ_TYPE_LEVEL_HIGH) { + return 0; + } else { + if (type == IRQ_TYPE_EDGE_RISING && + altera_gc->interrupt_trigger == IRQ_TYPE_EDGE_RISING) + return 0; + else if (type == IRQ_TYPE_EDGE_FALLING && + altera_gc->interrupt_trigger == IRQ_TYPE_EDGE_FALLING) + return 0; + else if (type == IRQ_TYPE_EDGE_BOTH && + altera_gc->interrupt_trigger == IRQ_TYPE_EDGE_BOTH) + return 0; + } + + return -EINVAL; +} + +static struct irq_chip altera_irq_chip = { + .name = "altera-gpio", + .irq_mask = altera_gpio_irq_mask, + .irq_unmask = altera_gpio_irq_unmask, + .irq_set_type = altera_gpio_irq_set_type, +}; + +static int altera_gpio_get(struct gpio_chip *gc, unsigned offset) +{ + struct of_mm_gpio_chip *mm_gc = to_of_mm_gpio_chip(gc); + + return (readl(mm_gc->regs + ALTERA_GPIO_DATA) >> offset) & 1; +} + +static void altera_gpio_set(struct gpio_chip *gc, unsigned offset, int value) +{ + struct of_mm_gpio_chip *mm_gc = to_of_mm_gpio_chip(gc); + struct altera_gpio_chip *chip = container_of(mm_gc, + struct altera_gpio_chip, mmchip); + unsigned long flags; + unsigned int data_reg; + + spin_lock_irqsave(&chip->gpio_lock, flags); + data_reg = readl(mm_gc->regs + ALTERA_GPIO_DATA); + data_reg = (data_reg & ~BIT(offset)) | (value << offset); + writel(data_reg, mm_gc->regs + ALTERA_GPIO_DATA); + spin_unlock_irqrestore(&chip->gpio_lock, flags); +} + +static int altera_gpio_direction_input(struct gpio_chip *gc, unsigned offset) +{ + struct of_mm_gpio_chip *mm_gc = to_of_mm_gpio_chip(gc); + struct altera_gpio_chip *chip = container_of(mm_gc, + struct altera_gpio_chip, mmchip); + unsigned long flags; + unsigned int gpio_ddr; + + spin_lock_irqsave(&chip->gpio_lock, flags); + /* Set pin as input, assumes software controlled IP */ + gpio_ddr = readl(mm_gc->regs + ALTERA_GPIO_DIR); + gpio_ddr &= ~BIT(offset); + writel(gpio_ddr, mm_gc->regs + ALTERA_GPIO_DIR); + spin_unlock_irqrestore(&chip->gpio_lock, flags); + + return 0; +} + +static int altera_gpio_direction_output(struct gpio_chip *gc, + unsigned offset, int value) +{ + struct of_mm_gpio_chip *mm_gc = to_of_mm_gpio_chip(gc); + struct altera_gpio_chip *chip = container_of(mm_gc, + struct altera_gpio_chip, mmchip); + unsigned long flags; + unsigned int data_reg, gpio_ddr; + + spin_lock_irqsave(&chip->gpio_lock, flags); + /* Sets the GPIO value */ + data_reg = readl(mm_gc->regs + ALTERA_GPIO_DATA); + data_reg = (data_reg & ~BIT(offset)) | (value << offset); + writel(data_reg, mm_gc->regs + ALTERA_GPIO_DATA); + + /* Set pin as output, assumes software controlled IP */ + gpio_ddr = readl(mm_gc->regs + ALTERA_GPIO_DIR); + gpio_ddr |= BIT(offset); + writel(gpio_ddr, mm_gc->regs + ALTERA_GPIO_DIR); + spin_unlock_irqrestore(&chip->gpio_lock, flags); + + return 0; +} + +static int altera_gpio_to_irq(struct gpio_chip *gc, unsigned offset) +{ + struct of_mm_gpio_chip *mm_gc = to_of_mm_gpio_chip(gc); + struct altera_gpio_chip *altera_gc = container_of(mm_gc, + struct altera_gpio_chip, mmchip); + + if (!altera_gc->irq) + return -ENXIO; + if (offset < altera_gc->mmchip.gc.ngpio) + return irq_create_mapping(altera_gc->irq, offset); + else + return -ENXIO; +} + +static void altera_gpio_irq_handler(unsigned int irq, struct irq_desc *desc) +{ + struct altera_gpio_chip *altera_gc = irq_desc_get_handler_data(desc); + struct irq_chip *chip = irq_desc_get_chip(desc); + struct of_mm_gpio_chip *mm_gc = &altera_gc->mmchip; + unsigned long status; + + int i; + chip->irq_mask(&desc->irq_data); + + /* Handling for level trigger and edge trigger is different */ + if (altera_gc->interrupt_trigger == IRQ_TYPE_LEVEL_HIGH) { + status = readl_relaxed(mm_gc->regs + ALTERA_GPIO_DATA); + status &= readl_relaxed(mm_gc->regs + ALTERA_GPIO_IRQ_MASK); + + for (i = 0; i < mm_gc->gc.ngpio; i++) { + if (BIT(i) & status) { + generic_handle_irq(irq_linear_revmap( + altera_gc->irq, i)); + } + } + } else { + while ((status = + (readl_relaxed(mm_gc->regs + ALTERA_GPIO_EDGE_CAP) & + readl_relaxed(mm_gc->regs + ALTERA_GPIO_IRQ_MASK)))) { + writel_relaxed(status, + mm_gc->regs + ALTERA_GPIO_EDGE_CAP); + for (i = 0; i < mm_gc->gc.ngpio; i++) { + if (BIT(i) & status) { + generic_handle_irq(irq_linear_revmap( + altera_gc->irq, i)); + } + } + } + } + + chip->irq_eoi(irq_desc_get_irq_data(desc)); + chip->irq_unmask(&desc->irq_data); +} + +static int altera_gpio_irq_map(struct irq_domain *h, unsigned int virq, + irq_hw_number_t hw_irq_num) +{ + irq_set_chip_data(virq, h->host_data); + irq_set_chip_and_handler(virq, &altera_irq_chip, handle_level_irq); + irq_set_irq_type(virq, IRQ_TYPE_NONE); + + return 0; +} + +static struct irq_domain_ops altera_gpio_irq_ops = { + .map = altera_gpio_irq_map, + .xlate = irq_domain_xlate_onecell, +}; + +int altera_gpio_probe(struct platform_device *pdev) +{ + struct device_node *node = pdev->dev.of_node; + int id, reg, ret; + struct altera_gpio_chip *altera_gc = devm_kzalloc(&pdev->dev, + sizeof(*altera_gc), GFP_KERNEL); + if (altera_gc == NULL) { + pr_err("%s: out of memory\n", node->full_name); + return -ENOMEM; + } + altera_gc->irq = 0; + + spin_lock_init(&altera_gc->gpio_lock); + + id = pdev->id; + + if (of_property_read_u32(node, "altr,gpio-bank-width", ®)) + /*By default assume full GPIO controller*/ + altera_gc->mmchip.gc.ngpio = 32; + else + altera_gc->mmchip.gc.ngpio = reg; + + if (altera_gc->mmchip.gc.ngpio > 32) { + pr_warn("%s: ngpio is greater than 32, defaulting to 32\n", + node->full_name); + altera_gc->mmchip.gc.ngpio = 32; + } + + altera_gc->mmchip.gc.direction_input = altera_gpio_direction_input; + altera_gc->mmchip.gc.direction_output = altera_gpio_direction_output; + altera_gc->mmchip.gc.get = altera_gpio_get; + altera_gc->mmchip.gc.set = altera_gpio_set; + altera_gc->mmchip.gc.to_irq = altera_gpio_to_irq; + altera_gc->mmchip.gc.owner = THIS_MODULE; + + ret = of_mm_gpiochip_add(node, &altera_gc->mmchip); + if (ret) { + pr_err("%s: Failed adding memory mapped gpiochip\n", + node->full_name); + return ret; + } + + platform_set_drvdata(pdev, altera_gc); + + altera_gc->mapped_irq = irq_of_parse_and_map(node, 0); + + if (!altera_gc->mapped_irq) + goto skip_irq; + + altera_gc->irq = irq_domain_add_linear(node, altera_gc->mmchip.gc.ngpio, + &altera_gpio_irq_ops, altera_gc); + + if (!altera_gc->irq) { + ret = -ENODEV; + goto dispose_irq; + } + + if (of_property_read_u32(node, "altr,interrupt_trigger", ®)) { + ret = -EINVAL; + pr_err("%s: interrupt_trigger value not set in device tree\n", + node->full_name); + goto teardown; + } + altera_gc->interrupt_trigger = reg; + + irq_set_handler_data(altera_gc->mapped_irq, altera_gc); + irq_set_chained_handler(altera_gc->mapped_irq, altera_gpio_irq_handler); + + return 0; + +teardown: + irq_domain_remove(altera_gc->irq); +dispose_irq: + irq_dispose_mapping(altera_gc->mapped_irq); + WARN_ON(gpiochip_remove(&altera_gc->mmchip.gc) < 0); + + pr_err("%s: registration failed with status %d\n", + node->full_name, ret); + + return ret; +skip_irq: + return 0; +} + +static int altera_gpio_remove(struct platform_device *pdev) +{ + unsigned int irq, i; + int status; + struct altera_gpio_chip *altera_gc = platform_get_drvdata(pdev); + + status = gpiochip_remove(&altera_gc->mmchip.gc); + + if (status < 0) + return status; + + if (altera_gc->irq) { + irq_dispose_mapping(altera_gc->mapped_irq); + + for (i = 0; i < altera_gc->mmchip.gc.ngpio; i++) { + irq = irq_find_mapping(altera_gc->irq, i); + if (irq > 0) + irq_dispose_mapping(irq); + } + + irq_domain_remove(altera_gc->irq); + } + + irq_set_handler_data(altera_gc->mapped_irq, NULL); + irq_set_chained_handler(altera_gc->mapped_irq, NULL); + return -EIO; +} + +static struct of_device_id altera_gpio_of_match[] = { + { .compatible = "altr,pio-1.0", }, + {}, +}; +MODULE_DEVICE_TABLE(of, altera_gpio_of_match); + +static struct platform_driver altera_gpio_driver = { + .driver = { + .name = "altera_gpio", + .owner = THIS_MODULE, + .of_match_table = of_match_ptr(altera_gpio_of_match), + }, + .probe = altera_gpio_probe, + .remove = altera_gpio_remove, +}; + +static int __init altera_gpio_init(void) +{ + return platform_driver_register(&altera_gpio_driver); +} +subsys_initcall(altera_gpio_init); + +static void __exit altera_gpio_exit(void) +{ + platform_driver_unregister(&altera_gpio_driver); +} +module_exit(altera_gpio_exit); + +MODULE_AUTHOR("Tien Hock Loh <thloh@xxxxxxxxxx>"); +MODULE_DESCRIPTION("Altera GPIO driver"); +MODULE_LICENSE("GPL"); -- 1.7.11.GIT -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html