2 * GPIO Driver for Loongson 1 SoC
4 * Copyright (C) 2015-2016 Zhang, Keguang <keguang.zhang@gmail.com>
6 * This file is licensed under the terms of the GNU General Public
7 * License version 2. This program is licensed "as is" without any
8 * warranty of any kind, whether express or implied.
11 #include <linux/gpio/driver.h>
12 #include <linux/platform_device.h>
14 /* Loongson 1 GPIO Register Definitions */
17 #define GPIO_DATA 0x20
18 #define GPIO_OUTPUT 0x30
20 static void __iomem *gpio_reg_base;
22 static int ls1x_gpio_request(struct gpio_chip *gc, unsigned int offset)
24 unsigned long pinmask = gc->pin2mask(gc, offset);
27 spin_lock_irqsave(&gc->bgpio_lock, flags);
28 __raw_writel(__raw_readl(gpio_reg_base + GPIO_CFG) | pinmask,
29 gpio_reg_base + GPIO_CFG);
30 spin_unlock_irqrestore(&gc->bgpio_lock, flags);
35 static void ls1x_gpio_free(struct gpio_chip *gc, unsigned int offset)
37 unsigned long pinmask = gc->pin2mask(gc, offset);
40 spin_lock_irqsave(&gc->bgpio_lock, flags);
41 __raw_writel(__raw_readl(gpio_reg_base + GPIO_CFG) & ~pinmask,
42 gpio_reg_base + GPIO_CFG);
43 spin_unlock_irqrestore(&gc->bgpio_lock, flags);
46 static int ls1x_gpio_probe(struct platform_device *pdev)
48 struct device *dev = &pdev->dev;
53 gc = devm_kzalloc(dev, sizeof(*gc), GFP_KERNEL);
57 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
59 dev_err(dev, "failed to get I/O memory\n");
63 gpio_reg_base = devm_ioremap_resource(dev, res);
64 if (IS_ERR(gpio_reg_base))
65 return PTR_ERR(gpio_reg_base);
67 ret = bgpio_init(gc, dev, 4, gpio_reg_base + GPIO_DATA,
68 gpio_reg_base + GPIO_OUTPUT, NULL,
69 NULL, gpio_reg_base + GPIO_DIR, 0);
73 gc->owner = THIS_MODULE;
74 gc->request = ls1x_gpio_request;
75 gc->free = ls1x_gpio_free;
76 gc->base = pdev->id * 32;
78 ret = devm_gpiochip_add_data(dev, gc, NULL);
82 platform_set_drvdata(pdev, gc);
83 dev_info(dev, "Loongson1 GPIO driver registered\n");
87 dev_err(dev, "failed to register GPIO device\n");
91 static struct platform_driver ls1x_gpio_driver = {
92 .probe = ls1x_gpio_probe,
98 module_platform_driver(ls1x_gpio_driver);
100 MODULE_AUTHOR("Kelvin Cheung <keguang.zhang@gmail.com>");
101 MODULE_DESCRIPTION("Loongson1 GPIO driver");
102 MODULE_LICENSE("GPL");