diff options
Diffstat (limited to 'drivers/gpio/gpio-moxart.c')
| -rw-r--r-- | drivers/gpio/gpio-moxart.c | 154 |
1 files changed, 154 insertions, 0 deletions
diff --git a/drivers/gpio/gpio-moxart.c b/drivers/gpio/gpio-moxart.c new file mode 100644 index 00000000000..4661e181be0 --- /dev/null +++ b/drivers/gpio/gpio-moxart.c @@ -0,0 +1,154 @@ +/* + * MOXA ART SoCs GPIO driver. + * + * Copyright (C) 2013 Jonas Jensen + * + * Jonas Jensen <jonas.jensen@gmail.com> + * + * 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. + */ + +#include <linux/err.h> +#include <linux/init.h> +#include <linux/irq.h> +#include <linux/io.h> +#include <linux/gpio.h> +#include <linux/platform_device.h> +#include <linux/module.h> +#include <linux/of_address.h> +#include <linux/of_gpio.h> +#include <linux/pinctrl/consumer.h> +#include <linux/delay.h> +#include <linux/timer.h> +#include <linux/bitops.h> + +#define GPIO_DATA_OUT 0x00 +#define GPIO_DATA_IN 0x04 +#define GPIO_PIN_DIRECTION 0x08 + +struct moxart_gpio_chip { + struct gpio_chip gpio; + void __iomem *base; +}; + +static inline struct moxart_gpio_chip *to_moxart_gpio(struct gpio_chip *chip) +{ + return container_of(chip, struct moxart_gpio_chip, gpio); +} + +static int moxart_gpio_request(struct gpio_chip *chip, unsigned offset) +{ + return pinctrl_request_gpio(offset); +} + +static void moxart_gpio_free(struct gpio_chip *chip, unsigned offset) +{ + pinctrl_free_gpio(offset); +} + +static void moxart_gpio_set(struct gpio_chip *chip, unsigned offset, int value) +{ + struct moxart_gpio_chip *gc = to_moxart_gpio(chip); + void __iomem *ioaddr = gc->base + GPIO_DATA_OUT; + u32 reg = readl(ioaddr); + + if (value) + reg = reg | BIT(offset); + else + reg = reg & ~BIT(offset); + + writel(reg, ioaddr); +} + +static int moxart_gpio_get(struct gpio_chip *chip, unsigned offset) +{ + struct moxart_gpio_chip *gc = to_moxart_gpio(chip); + u32 ret = readl(gc->base + GPIO_PIN_DIRECTION); + + if (ret & BIT(offset)) + return !!(readl(gc->base + GPIO_DATA_OUT) & BIT(offset)); + else + return !!(readl(gc->base + GPIO_DATA_IN) & BIT(offset)); +} + +static int moxart_gpio_direction_input(struct gpio_chip *chip, unsigned offset) +{ + struct moxart_gpio_chip *gc = to_moxart_gpio(chip); + void __iomem *ioaddr = gc->base + GPIO_PIN_DIRECTION; + + writel(readl(ioaddr) & ~BIT(offset), ioaddr); + return 0; +} + +static int moxart_gpio_direction_output(struct gpio_chip *chip, + unsigned offset, int value) +{ + struct moxart_gpio_chip *gc = to_moxart_gpio(chip); + void __iomem *ioaddr = gc->base + GPIO_PIN_DIRECTION; + + moxart_gpio_set(chip, offset, value); + writel(readl(ioaddr) | BIT(offset), ioaddr); + return 0; +} + +static struct gpio_chip moxart_template_chip = { + .label = "moxart-gpio", + .request = moxart_gpio_request, + .free = moxart_gpio_free, + .direction_input = moxart_gpio_direction_input, + .direction_output = moxart_gpio_direction_output, + .set = moxart_gpio_set, + .get = moxart_gpio_get, + .ngpio = 32, + .owner = THIS_MODULE, +}; + +static int moxart_gpio_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct resource *res; + struct moxart_gpio_chip *mgc; + int ret; + + mgc = devm_kzalloc(dev, sizeof(*mgc), GFP_KERNEL); + if (!mgc) + return -ENOMEM; + mgc->gpio = moxart_template_chip; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + mgc->base = devm_ioremap_resource(dev, res); + if (IS_ERR(mgc->base)) + return PTR_ERR(mgc->base); + + mgc->gpio.dev = dev; + + ret = gpiochip_add(&mgc->gpio); + if (ret) { + dev_err(dev, "%s: gpiochip_add failed\n", + dev->of_node->full_name); + return ret; + } + + return 0; +} + +static const struct of_device_id moxart_gpio_match[] = { + { .compatible = "moxa,moxart-gpio" }, + { } +}; + +static struct platform_driver moxart_gpio_driver = { + .driver = { + .name = "moxart-gpio", + .owner = THIS_MODULE, + .of_match_table = moxart_gpio_match, + }, + .probe = moxart_gpio_probe, +}; +module_platform_driver(moxart_gpio_driver); + +MODULE_DESCRIPTION("MOXART GPIO chip driver"); +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Jonas Jensen <jonas.jensen@gmail.com>"); |