diff options
Diffstat (limited to 'drivers/gpio/gpio-rcar.c')
| -rw-r--r-- | drivers/gpio/gpio-rcar.c | 373 |
1 files changed, 373 insertions, 0 deletions
diff --git a/drivers/gpio/gpio-rcar.c b/drivers/gpio/gpio-rcar.c new file mode 100644 index 000000000000..581ba56131a7 --- /dev/null +++ b/drivers/gpio/gpio-rcar.c @@ -0,0 +1,373 @@ +/* + * Renesas R-Car GPIO Support + * + * Copyright (C) 2013 Magnus Damm + * + * 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 + * + * 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/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/irqdomain.h> +#include <linux/module.h> +#include <linux/platform_data/gpio-rcar.h> +#include <linux/platform_device.h> +#include <linux/spinlock.h> +#include <linux/slab.h> + +struct gpio_rcar_priv { + void __iomem *base; + spinlock_t lock; + struct gpio_rcar_config config; + struct platform_device *pdev; + struct gpio_chip gpio_chip; + struct irq_chip irq_chip; + struct irq_domain *irq_domain; +}; + +#define IOINTSEL 0x00 +#define INOUTSEL 0x04 +#define OUTDT 0x08 +#define INDT 0x0c +#define INTDT 0x10 +#define INTCLR 0x14 +#define INTMSK 0x18 +#define MSKCLR 0x1c +#define POSNEG 0x20 +#define EDGLEVEL 0x24 +#define FILONOFF 0x28 + +static inline u32 gpio_rcar_read(struct gpio_rcar_priv *p, int offs) +{ + return ioread32(p->base + offs); +} + +static inline void gpio_rcar_write(struct gpio_rcar_priv *p, int offs, + u32 value) +{ + iowrite32(value, p->base + offs); +} + +static void gpio_rcar_modify_bit(struct gpio_rcar_priv *p, int offs, + int bit, bool value) +{ + u32 tmp = gpio_rcar_read(p, offs); + + if (value) + tmp |= BIT(bit); + else + tmp &= ~BIT(bit); + + gpio_rcar_write(p, offs, tmp); +} + +static void gpio_rcar_irq_disable(struct irq_data *d) +{ + struct gpio_rcar_priv *p = irq_data_get_irq_chip_data(d); + + gpio_rcar_write(p, INTMSK, ~BIT(irqd_to_hwirq(d))); +} + +static void gpio_rcar_irq_enable(struct irq_data *d) +{ + struct gpio_rcar_priv *p = irq_data_get_irq_chip_data(d); + + gpio_rcar_write(p, MSKCLR, BIT(irqd_to_hwirq(d))); +} + +static void gpio_rcar_config_interrupt_input_mode(struct gpio_rcar_priv *p, + unsigned int hwirq, + bool active_high_rising_edge, + bool level_trigger) +{ + unsigned long flags; + + /* follow steps in the GPIO documentation for + * "Setting Edge-Sensitive Interrupt Input Mode" and + * "Setting Level-Sensitive Interrupt Input Mode" + */ + + spin_lock_irqsave(&p->lock, flags); + + /* Configure postive or negative logic in POSNEG */ + gpio_rcar_modify_bit(p, POSNEG, hwirq, !active_high_rising_edge); + + /* Configure edge or level trigger in EDGLEVEL */ + gpio_rcar_modify_bit(p, EDGLEVEL, hwirq, !level_trigger); + + /* Select "Interrupt Input Mode" in IOINTSEL */ + gpio_rcar_modify_bit(p, IOINTSEL, hwirq, true); + + /* Write INTCLR in case of edge trigger */ + if (!level_trigger) + gpio_rcar_write(p, INTCLR, BIT(hwirq)); + + spin_unlock_irqrestore(&p->lock, flags); +} + +static int gpio_rcar_irq_set_type(struct irq_data *d, unsigned int type) +{ + struct gpio_rcar_priv *p = irq_data_get_irq_chip_data(d); + unsigned int hwirq = irqd_to_hwirq(d); + + dev_dbg(&p->pdev->dev, "sense irq = %d, type = %d\n", hwirq, type); + + switch (type & IRQ_TYPE_SENSE_MASK) { + case IRQ_TYPE_LEVEL_HIGH: + gpio_rcar_config_interrupt_input_mode(p, hwirq, true, true); + break; + case IRQ_TYPE_LEVEL_LOW: + gpio_rcar_config_interrupt_input_mode(p, hwirq, false, true); + break; + case IRQ_TYPE_EDGE_RISING: + gpio_rcar_config_interrupt_input_mode(p, hwirq, true, false); + break; + case IRQ_TYPE_EDGE_FALLING: + gpio_rcar_config_interrupt_input_mode(p, hwirq, false, false); + break; + default: + return -EINVAL; + } + return 0; +} + +static irqreturn_t gpio_rcar_irq_handler(int irq, void *dev_id) +{ + struct gpio_rcar_priv *p = dev_id; + u32 pending; + unsigned int offset, irqs_handled = 0; + + while ((pending = gpio_rcar_read(p, INTDT))) { + offset = __ffs(pending); + gpio_rcar_write(p, INTCLR, BIT(offset)); + generic_handle_irq(irq_find_mapping(p->irq_domain, offset)); + irqs_handled++; + } + + return irqs_handled ? IRQ_HANDLED : IRQ_NONE; +} + +static inline struct gpio_rcar_priv *gpio_to_priv(struct gpio_chip *chip) +{ + return container_of(chip, struct gpio_rcar_priv, gpio_chip); +} + +static void gpio_rcar_config_general_input_output_mode(struct gpio_chip *chip, + unsigned int gpio, + bool output) +{ + struct gpio_rcar_priv *p = gpio_to_priv(chip); + unsigned long flags; + + /* follow steps in the GPIO documentation for + * "Setting General Output Mode" and + * "Setting General Input Mode" + */ + + spin_lock_irqsave(&p->lock, flags); + + /* Configure postive logic in POSNEG */ + gpio_rcar_modify_bit(p, POSNEG, gpio, false); + + /* Select "General Input/Output Mode" in IOINTSEL */ + gpio_rcar_modify_bit(p, IOINTSEL, gpio, false); + + /* Select Input Mode or Output Mode in INOUTSEL */ + gpio_rcar_modify_bit(p, INOUTSEL, gpio, output); + + spin_unlock_irqrestore(&p->lock, flags); +} + +static int gpio_rcar_direction_input(struct gpio_chip *chip, unsigned offset) +{ + gpio_rcar_config_general_input_output_mode(chip, offset, false); + return 0; +} + +static int gpio_rcar_get(struct gpio_chip *chip, unsigned offset) +{ + return (int)(gpio_rcar_read(gpio_to_priv(chip), INDT) & BIT(offset)); +} + +static void gpio_rcar_set(struct gpio_chip *chip, unsigned offset, int value) +{ + struct gpio_rcar_priv *p = gpio_to_priv(chip); + unsigned long flags; + + spin_lock_irqsave(&p->lock, flags); + gpio_rcar_modify_bit(p, OUTDT, offset, value); + spin_unlock_irqrestore(&p->lock, flags); +} + +static int gpio_rcar_direction_output(struct gpio_chip *chip, unsigned offset, + int value) +{ + /* write GPIO value to output before selecting output mode of pin */ + gpio_rcar_set(chip, offset, value); + gpio_rcar_config_general_input_output_mode(chip, offset, true); + return 0; +} + +static int gpio_rcar_to_irq(struct gpio_chip *chip, unsigned offset) +{ + return irq_create_mapping(gpio_to_priv(chip)->irq_domain, offset); +} + +static int gpio_rcar_irq_domain_map(struct irq_domain *h, unsigned int virq, + irq_hw_number_t hw) +{ + struct gpio_rcar_priv *p = h->host_data; + + dev_dbg(&p->pdev->dev, "map hw irq = %d, virq = %d\n", (int)hw, virq); + + irq_set_chip_data(virq, h->host_data); + irq_set_chip_and_handler(virq, &p->irq_chip, handle_level_irq); + set_irq_flags(virq, IRQF_VALID); /* kill me now */ + return 0; +} + +static struct irq_domain_ops gpio_rcar_irq_domain_ops = { + .map = gpio_rcar_irq_domain_map, +}; + +static int gpio_rcar_probe(struct platform_device *pdev) +{ + struct gpio_rcar_config *pdata = pdev->dev.platform_data; + struct gpio_rcar_priv *p; + struct resource *io, *irq; + struct gpio_chip *gpio_chip; + struct irq_chip *irq_chip; + const char *name = dev_name(&pdev->dev); + int ret; + + p = devm_kzalloc(&pdev->dev, sizeof(*p), GFP_KERNEL); + if (!p) { + dev_err(&pdev->dev, "failed to allocate driver data\n"); + ret = -ENOMEM; + goto err0; + } + + /* deal with driver instance configuration */ + if (pdata) + p->config = *pdata; + + p->pdev = pdev; + platform_set_drvdata(pdev, p); + spin_lock_init(&p->lock); + + io = platform_get_resource(pdev, IORESOURCE_MEM, 0); + irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0); + + if (!io || !irq) { + dev_err(&pdev->dev, "missing IRQ or IOMEM\n"); + ret = -EINVAL; + goto err0; + } + + p->base = devm_ioremap_nocache(&pdev->dev, io->start, + resource_size(io)); + if (!p->base) { + dev_err(&pdev->dev, "failed to remap I/O memory\n"); + ret = -ENXIO; + goto err0; + } + + gpio_chip = &p->gpio_chip; + gpio_chip->direction_input = gpio_rcar_direction_input; + gpio_chip->get = gpio_rcar_get; + gpio_chip->direction_output = gpio_rcar_direction_output; + gpio_chip->set = gpio_rcar_set; + gpio_chip->to_irq = gpio_rcar_to_irq; + gpio_chip->label = name; + gpio_chip->owner = THIS_MODULE; + gpio_chip->base = p->config.gpio_base; + gpio_chip->ngpio = p->config.number_of_pins; + + irq_chip = &p->irq_chip; + irq_chip->name = name; + irq_chip->irq_mask = gpio_rcar_irq_disable; + irq_chip->irq_unmask = gpio_rcar_irq_enable; + irq_chip->irq_enable = gpio_rcar_irq_enable; + irq_chip->irq_disable = gpio_rcar_irq_disable; + irq_chip->irq_set_type = gpio_rcar_irq_set_type; + irq_chip->flags = IRQCHIP_SKIP_SET_WAKE | IRQCHIP_SET_TYPE_MASKED; + + p->irq_domain = irq_domain_add_simple(pdev->dev.of_node, + p->config.number_of_pins, + p->config.irq_base, + &gpio_rcar_irq_domain_ops, p); + if (!p->irq_domain) { + ret = -ENXIO; + dev_err(&pdev->dev, "cannot initialize irq domain\n"); + goto err1; + } + + if (devm_request_irq(&pdev->dev, irq->start, + gpio_rcar_irq_handler, 0, name, p)) { + dev_err(&pdev->dev, "failed to request IRQ\n"); + ret = -ENOENT; + goto err1; + } + + ret = gpiochip_add(gpio_chip); + if (ret) { + dev_err(&pdev->dev, "failed to add GPIO controller\n"); + goto err1; + } + + dev_info(&pdev->dev, "driving %d GPIOs\n", p->config.number_of_pins); + + /* warn in case of mismatch if irq base is specified */ + if (p->config.irq_base) { + ret = irq_find_mapping(p->irq_domain, 0); + if (p->config.irq_base != ret) + dev_warn(&pdev->dev, "irq base mismatch (%u/%u)\n", + p->config.irq_base, ret); + } + + return 0; + +err1: + irq_domain_remove(p->irq_domain); +err0: + return ret; +} + +static int gpio_rcar_remove(struct platform_device *pdev) +{ + struct gpio_rcar_priv *p = platform_get_drvdata(pdev); + int ret; + + ret = gpiochip_remove(&p->gpio_chip); + if (ret) + return ret; + + irq_domain_remove(p->irq_domain); + return 0; +} + +static struct platform_driver gpio_rcar_device_driver = { + .probe = gpio_rcar_probe, + .remove = gpio_rcar_remove, + .driver = { + .name = "gpio_rcar", + } +}; + +module_platform_driver(gpio_rcar_device_driver); + +MODULE_AUTHOR("Magnus Damm"); +MODULE_DESCRIPTION("Renesas R-Car GPIO Driver"); +MODULE_LICENSE("GPL v2"); |