2 * MOXA ART SoCs GPIO driver.
4 * Copyright (C) 2013 Jonas Jensen
6 * Jonas Jensen <jonas.jensen@gmail.com>
8 * This file is licensed under the terms of the GNU General Public
9 * License version 2. This program is licensed "as is" without any
10 * warranty of any kind, whether express or implied.
13 #include <linux/err.h>
14 #include <linux/init.h>
15 #include <linux/irq.h>
17 #include <linux/gpio.h>
18 #include <linux/platform_device.h>
19 #include <linux/module.h>
20 #include <linux/of_address.h>
21 #include <linux/of_gpio.h>
22 #include <linux/pinctrl/consumer.h>
23 #include <linux/delay.h>
24 #include <linux/timer.h>
25 #include <linux/bitops.h>
27 #define GPIO_DATA_OUT 0x00
28 #define GPIO_DATA_IN 0x04
29 #define GPIO_PIN_DIRECTION 0x08
31 struct moxart_gpio_chip {
32 struct gpio_chip gpio;
33 void __iomem *moxart_gpio_base;
36 static inline struct moxart_gpio_chip *to_moxart_gpio(struct gpio_chip *chip)
38 return container_of(chip, struct moxart_gpio_chip, gpio);
41 static int moxart_gpio_request(struct gpio_chip *chip, unsigned offset)
43 return pinctrl_request_gpio(offset);
46 static void moxart_gpio_free(struct gpio_chip *chip, unsigned offset)
48 pinctrl_free_gpio(offset);
51 static int moxart_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
53 struct moxart_gpio_chip *gc = to_moxart_gpio(chip);
54 void __iomem *ioaddr = gc->moxart_gpio_base + GPIO_PIN_DIRECTION;
56 writel(readl(ioaddr) & ~BIT(offset), ioaddr);
60 static int moxart_gpio_direction_output(struct gpio_chip *chip,
61 unsigned offset, int value)
63 struct moxart_gpio_chip *gc = to_moxart_gpio(chip);
64 void __iomem *ioaddr = gc->moxart_gpio_base + GPIO_PIN_DIRECTION;
66 writel(readl(ioaddr) | BIT(offset), ioaddr);
70 static void moxart_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
72 struct moxart_gpio_chip *gc = to_moxart_gpio(chip);
73 void __iomem *ioaddr = gc->moxart_gpio_base + GPIO_DATA_OUT;
74 u32 reg = readl(ioaddr);
77 reg = reg | BIT(offset);
79 reg = reg & ~BIT(offset);
85 static int moxart_gpio_get(struct gpio_chip *chip, unsigned offset)
87 struct moxart_gpio_chip *gc = to_moxart_gpio(chip);
88 u32 ret = readl(gc->moxart_gpio_base + GPIO_PIN_DIRECTION);
90 if (ret & BIT(offset))
91 return !!(readl(gc->moxart_gpio_base + GPIO_DATA_OUT) &
94 return !!(readl(gc->moxart_gpio_base + GPIO_DATA_IN) &
98 static struct gpio_chip moxart_template_chip = {
99 .label = "moxart-gpio",
100 .request = moxart_gpio_request,
101 .free = moxart_gpio_free,
102 .direction_input = moxart_gpio_direction_input,
103 .direction_output = moxart_gpio_direction_output,
104 .set = moxart_gpio_set,
105 .get = moxart_gpio_get,
111 static int moxart_gpio_probe(struct platform_device *pdev)
113 struct device *dev = &pdev->dev;
114 struct resource *res;
115 struct moxart_gpio_chip *mgc;
118 mgc = devm_kzalloc(dev, sizeof(*mgc), GFP_KERNEL);
120 dev_err(dev, "can't allocate GPIO chip container\n");
123 mgc->gpio = moxart_template_chip;
125 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
126 mgc->moxart_gpio_base = devm_ioremap_resource(dev, res);
127 if (IS_ERR(mgc->moxart_gpio_base)) {
128 dev_err(dev, "%s: devm_ioremap_resource res_gpio failed\n",
129 dev->of_node->full_name);
130 return PTR_ERR(mgc->moxart_gpio_base);
135 ret = gpiochip_add(&mgc->gpio);
137 dev_err(dev, "%s: gpiochip_add failed\n",
138 dev->of_node->full_name);
145 static const struct of_device_id moxart_gpio_match[] = {
146 { .compatible = "moxa,moxart-gpio" },
150 static struct platform_driver moxart_gpio_driver = {
152 .name = "moxart-gpio",
153 .owner = THIS_MODULE,
154 .of_match_table = moxart_gpio_match,
156 .probe = moxart_gpio_probe,
158 module_platform_driver(moxart_gpio_driver);
160 MODULE_DESCRIPTION("MOXART GPIO chip driver");
161 MODULE_LICENSE("GPL");
162 MODULE_AUTHOR("Jonas Jensen <jonas.jensen@gmail.com>");