diff options
Diffstat (limited to 'kernel/drivers/gpio/gpio-vf610.c')
-rw-r--r-- | kernel/drivers/gpio/gpio-vf610.c | 294 |
1 files changed, 294 insertions, 0 deletions
diff --git a/kernel/drivers/gpio/gpio-vf610.c b/kernel/drivers/gpio/gpio-vf610.c new file mode 100644 index 000000000..7bd9f209f --- /dev/null +++ b/kernel/drivers/gpio/gpio-vf610.c @@ -0,0 +1,294 @@ +/* + * vf610 GPIO support through PORT and GPIO module + * + * Copyright (c) 2014 Toradex AG. + * + * Author: Stefan Agner <stefan@agner.ch>. + * + * 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. + */ + +#include <linux/bitops.h> +#include <linux/err.h> +#include <linux/gpio.h> +#include <linux/init.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/ioport.h> +#include <linux/irq.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/of.h> +#include <linux/of_device.h> +#include <linux/of_irq.h> + +#define VF610_GPIO_PER_PORT 32 + +struct vf610_gpio_port { + struct gpio_chip gc; + void __iomem *base; + void __iomem *gpio_base; + u8 irqc[VF610_GPIO_PER_PORT]; + int irq; +}; + +#define GPIO_PDOR 0x00 +#define GPIO_PSOR 0x04 +#define GPIO_PCOR 0x08 +#define GPIO_PTOR 0x0c +#define GPIO_PDIR 0x10 + +#define PORT_PCR(n) ((n) * 0x4) +#define PORT_PCR_IRQC_OFFSET 16 + +#define PORT_ISFR 0xa0 +#define PORT_DFER 0xc0 +#define PORT_DFCR 0xc4 +#define PORT_DFWR 0xc8 + +#define PORT_INT_OFF 0x0 +#define PORT_INT_LOGIC_ZERO 0x8 +#define PORT_INT_RISING_EDGE 0x9 +#define PORT_INT_FALLING_EDGE 0xa +#define PORT_INT_EITHER_EDGE 0xb +#define PORT_INT_LOGIC_ONE 0xc + +static const struct of_device_id vf610_gpio_dt_ids[] = { + { .compatible = "fsl,vf610-gpio" }, + { /* sentinel */ } +}; + +static inline void vf610_gpio_writel(u32 val, void __iomem *reg) +{ + writel_relaxed(val, reg); +} + +static inline u32 vf610_gpio_readl(void __iomem *reg) +{ + return readl_relaxed(reg); +} + +static int vf610_gpio_request(struct gpio_chip *chip, unsigned offset) +{ + return pinctrl_request_gpio(chip->base + offset); +} + +static void vf610_gpio_free(struct gpio_chip *chip, unsigned offset) +{ + pinctrl_free_gpio(chip->base + offset); +} + +static int vf610_gpio_get(struct gpio_chip *gc, unsigned int gpio) +{ + struct vf610_gpio_port *port = + container_of(gc, struct vf610_gpio_port, gc); + + return !!(vf610_gpio_readl(port->gpio_base + GPIO_PDIR) & BIT(gpio)); +} + +static void vf610_gpio_set(struct gpio_chip *gc, unsigned int gpio, int val) +{ + struct vf610_gpio_port *port = + container_of(gc, struct vf610_gpio_port, gc); + unsigned long mask = BIT(gpio); + + if (val) + vf610_gpio_writel(mask, port->gpio_base + GPIO_PSOR); + else + vf610_gpio_writel(mask, port->gpio_base + GPIO_PCOR); +} + +static int vf610_gpio_direction_input(struct gpio_chip *chip, unsigned gpio) +{ + return pinctrl_gpio_direction_input(chip->base + gpio); +} + +static int vf610_gpio_direction_output(struct gpio_chip *chip, unsigned gpio, + int value) +{ + vf610_gpio_set(chip, gpio, value); + + return pinctrl_gpio_direction_output(chip->base + gpio); +} + +static void vf610_gpio_irq_handler(u32 irq, struct irq_desc *desc) +{ + struct vf610_gpio_port *port = irq_get_handler_data(irq); + struct irq_chip *chip = irq_desc_get_chip(desc); + int pin; + unsigned long irq_isfr; + + chained_irq_enter(chip, desc); + + irq_isfr = vf610_gpio_readl(port->base + PORT_ISFR); + + for_each_set_bit(pin, &irq_isfr, VF610_GPIO_PER_PORT) { + vf610_gpio_writel(BIT(pin), port->base + PORT_ISFR); + + generic_handle_irq(irq_find_mapping(port->gc.irqdomain, pin)); + } + + chained_irq_exit(chip, desc); +} + +static void vf610_gpio_irq_ack(struct irq_data *d) +{ + struct vf610_gpio_port *port = irq_data_get_irq_chip_data(d); + int gpio = d->hwirq; + + vf610_gpio_writel(BIT(gpio), port->base + PORT_ISFR); +} + +static int vf610_gpio_irq_set_type(struct irq_data *d, u32 type) +{ + struct vf610_gpio_port *port = irq_data_get_irq_chip_data(d); + u8 irqc; + + switch (type) { + case IRQ_TYPE_EDGE_RISING: + irqc = PORT_INT_RISING_EDGE; + break; + case IRQ_TYPE_EDGE_FALLING: + irqc = PORT_INT_FALLING_EDGE; + break; + case IRQ_TYPE_EDGE_BOTH: + irqc = PORT_INT_EITHER_EDGE; + break; + case IRQ_TYPE_LEVEL_LOW: + irqc = PORT_INT_LOGIC_ZERO; + break; + case IRQ_TYPE_LEVEL_HIGH: + irqc = PORT_INT_LOGIC_ONE; + break; + default: + return -EINVAL; + } + + port->irqc[d->hwirq] = irqc; + + return 0; +} + +static void vf610_gpio_irq_mask(struct irq_data *d) +{ + struct vf610_gpio_port *port = irq_data_get_irq_chip_data(d); + void __iomem *pcr_base = port->base + PORT_PCR(d->hwirq); + + vf610_gpio_writel(0, pcr_base); +} + +static void vf610_gpio_irq_unmask(struct irq_data *d) +{ + struct vf610_gpio_port *port = irq_data_get_irq_chip_data(d); + void __iomem *pcr_base = port->base + PORT_PCR(d->hwirq); + + vf610_gpio_writel(port->irqc[d->hwirq] << PORT_PCR_IRQC_OFFSET, + pcr_base); +} + +static int vf610_gpio_irq_set_wake(struct irq_data *d, u32 enable) +{ + struct vf610_gpio_port *port = irq_data_get_irq_chip_data(d); + + if (enable) + enable_irq_wake(port->irq); + else + disable_irq_wake(port->irq); + + return 0; +} + +static struct irq_chip vf610_gpio_irq_chip = { + .name = "gpio-vf610", + .irq_ack = vf610_gpio_irq_ack, + .irq_mask = vf610_gpio_irq_mask, + .irq_unmask = vf610_gpio_irq_unmask, + .irq_set_type = vf610_gpio_irq_set_type, + .irq_set_wake = vf610_gpio_irq_set_wake, +}; + +static int vf610_gpio_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct device_node *np = dev->of_node; + struct vf610_gpio_port *port; + struct resource *iores; + struct gpio_chip *gc; + int ret; + + port = devm_kzalloc(&pdev->dev, sizeof(*port), GFP_KERNEL); + if (!port) + return -ENOMEM; + + iores = platform_get_resource(pdev, IORESOURCE_MEM, 0); + port->base = devm_ioremap_resource(dev, iores); + if (IS_ERR(port->base)) + return PTR_ERR(port->base); + + iores = platform_get_resource(pdev, IORESOURCE_MEM, 1); + port->gpio_base = devm_ioremap_resource(dev, iores); + if (IS_ERR(port->gpio_base)) + return PTR_ERR(port->gpio_base); + + port->irq = platform_get_irq(pdev, 0); + if (port->irq < 0) + return port->irq; + + gc = &port->gc; + gc->of_node = np; + gc->dev = dev; + gc->label = "vf610-gpio"; + gc->ngpio = VF610_GPIO_PER_PORT; + gc->base = of_alias_get_id(np, "gpio") * VF610_GPIO_PER_PORT; + + gc->request = vf610_gpio_request; + gc->free = vf610_gpio_free; + gc->direction_input = vf610_gpio_direction_input; + gc->get = vf610_gpio_get; + gc->direction_output = vf610_gpio_direction_output; + gc->set = vf610_gpio_set; + + ret = gpiochip_add(gc); + if (ret < 0) + return ret; + + /* Clear the interrupt status register for all GPIO's */ + vf610_gpio_writel(~0, port->base + PORT_ISFR); + + ret = gpiochip_irqchip_add(gc, &vf610_gpio_irq_chip, 0, + handle_simple_irq, IRQ_TYPE_NONE); + if (ret) { + dev_err(dev, "failed to add irqchip\n"); + gpiochip_remove(gc); + return ret; + } + gpiochip_set_chained_irqchip(gc, &vf610_gpio_irq_chip, port->irq, + vf610_gpio_irq_handler); + + return 0; +} + +static struct platform_driver vf610_gpio_driver = { + .driver = { + .name = "gpio-vf610", + .of_match_table = vf610_gpio_dt_ids, + }, + .probe = vf610_gpio_probe, +}; + +static int __init gpio_vf610_init(void) +{ + return platform_driver_register(&vf610_gpio_driver); +} +device_initcall(gpio_vf610_init); + +MODULE_AUTHOR("Stefan Agner <stefan@agner.ch>"); +MODULE_DESCRIPTION("Freescale VF610 GPIO"); +MODULE_LICENSE("GPL v2"); |