1/*
 2 * GPIO Driver for Loongson 1 SoC
 3 *
 4 * Copyright (C) 2015-2016 Zhang, Keguang <keguang.zhang@gmail.com>
 5 *
 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.
 9 */
10
11#include <linux/module.h>
12#include <linux/gpio/driver.h>
13#include <linux/platform_device.h>
14#include <linux/bitops.h>
15
16/* Loongson 1 GPIO Register Definitions */
17#define GPIO_CFG		0x0
18#define GPIO_DIR		0x10
19#define GPIO_DATA		0x20
20#define GPIO_OUTPUT		0x30
21
22static void __iomem *gpio_reg_base;
23
24static int ls1x_gpio_request(struct gpio_chip *gc, unsigned int offset)
25{
26	unsigned long flags;
27
28	raw_spin_lock_irqsave(&gc->bgpio_lock, flags);
29	__raw_writel(__raw_readl(gpio_reg_base + GPIO_CFG) | BIT(offset),
30		     gpio_reg_base + GPIO_CFG);
31	raw_spin_unlock_irqrestore(&gc->bgpio_lock, flags);
32
33	return 0;
34}
35
36static void ls1x_gpio_free(struct gpio_chip *gc, unsigned int offset)
37{
38	unsigned long flags;
39
40	raw_spin_lock_irqsave(&gc->bgpio_lock, flags);
41	__raw_writel(__raw_readl(gpio_reg_base + GPIO_CFG) & ~BIT(offset),
42		     gpio_reg_base + GPIO_CFG);
43	raw_spin_unlock_irqrestore(&gc->bgpio_lock, flags);
44}
45
46static int ls1x_gpio_probe(struct platform_device *pdev)
47{
48	struct device *dev = &pdev->dev;
49	struct gpio_chip *gc;
 
50	int ret;
51
52	gc = devm_kzalloc(dev, sizeof(*gc), GFP_KERNEL);
53	if (!gc)
54		return -ENOMEM;
55
56	gpio_reg_base = devm_platform_ioremap_resource(pdev, 0);
 
57	if (IS_ERR(gpio_reg_base))
58		return PTR_ERR(gpio_reg_base);
59
60	ret = bgpio_init(gc, dev, 4, gpio_reg_base + GPIO_DATA,
61			 gpio_reg_base + GPIO_OUTPUT, NULL,
62			 NULL, gpio_reg_base + GPIO_DIR, 0);
63	if (ret)
64		goto err;
65
66	gc->owner = THIS_MODULE;
67	gc->request = ls1x_gpio_request;
68	gc->free = ls1x_gpio_free;
69	gc->base = pdev->id * 32;
70
71	ret = devm_gpiochip_add_data(dev, gc, NULL);
72	if (ret)
73		goto err;
74
75	platform_set_drvdata(pdev, gc);
76	dev_info(dev, "Loongson1 GPIO driver registered\n");
77
78	return 0;
79err:
80	dev_err(dev, "failed to register GPIO device\n");
81	return ret;
82}
83
84static struct platform_driver ls1x_gpio_driver = {
85	.probe	= ls1x_gpio_probe,
86	.driver	= {
87		.name	= "ls1x-gpio",
88	},
89};
90
91module_platform_driver(ls1x_gpio_driver);
92
93MODULE_AUTHOR("Kelvin Cheung <keguang.zhang@gmail.com>");
94MODULE_DESCRIPTION("Loongson1 GPIO driver");
95MODULE_LICENSE("GPL");

 1/*
 2 * GPIO Driver for Loongson 1 SoC
 3 *
 4 * Copyright (C) 2015-2016 Zhang, Keguang <keguang.zhang@gmail.com>
 5 *
 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.
 9 */
10
11#include <linux/module.h>
12#include <linux/gpio/driver.h>
13#include <linux/platform_device.h>
14#include <linux/bitops.h>
15
16/* Loongson 1 GPIO Register Definitions */
17#define GPIO_CFG		0x0
18#define GPIO_DIR		0x10
19#define GPIO_DATA		0x20
20#define GPIO_OUTPUT		0x30
21
22static void __iomem *gpio_reg_base;
23
24static int ls1x_gpio_request(struct gpio_chip *gc, unsigned int offset)
25{
26	unsigned long flags;
27
28	spin_lock_irqsave(&gc->bgpio_lock, flags);
29	__raw_writel(__raw_readl(gpio_reg_base + GPIO_CFG) | BIT(offset),
30		     gpio_reg_base + GPIO_CFG);
31	spin_unlock_irqrestore(&gc->bgpio_lock, flags);
32
33	return 0;
34}
35
36static void ls1x_gpio_free(struct gpio_chip *gc, unsigned int offset)
37{
38	unsigned long flags;
39
40	spin_lock_irqsave(&gc->bgpio_lock, flags);
41	__raw_writel(__raw_readl(gpio_reg_base + GPIO_CFG) & ~BIT(offset),
42		     gpio_reg_base + GPIO_CFG);
43	spin_unlock_irqrestore(&gc->bgpio_lock, flags);
44}
45
46static int ls1x_gpio_probe(struct platform_device *pdev)
47{
48	struct device *dev = &pdev->dev;
49	struct gpio_chip *gc;
50	struct resource *res;
51	int ret;
52
53	gc = devm_kzalloc(dev, sizeof(*gc), GFP_KERNEL);
54	if (!gc)
55		return -ENOMEM;
56
57	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
58	gpio_reg_base = devm_ioremap_resource(dev, res);
59	if (IS_ERR(gpio_reg_base))
60		return PTR_ERR(gpio_reg_base);
61
62	ret = bgpio_init(gc, dev, 4, gpio_reg_base + GPIO_DATA,
63			 gpio_reg_base + GPIO_OUTPUT, NULL,
64			 NULL, gpio_reg_base + GPIO_DIR, 0);
65	if (ret)
66		goto err;
67
68	gc->owner = THIS_MODULE;
69	gc->request = ls1x_gpio_request;
70	gc->free = ls1x_gpio_free;
71	gc->base = pdev->id * 32;
72
73	ret = devm_gpiochip_add_data(dev, gc, NULL);
74	if (ret)
75		goto err;
76
77	platform_set_drvdata(pdev, gc);
78	dev_info(dev, "Loongson1 GPIO driver registered\n");
79
80	return 0;
81err:
82	dev_err(dev, "failed to register GPIO device\n");
83	return ret;
84}
85
86static struct platform_driver ls1x_gpio_driver = {
87	.probe	= ls1x_gpio_probe,
88	.driver	= {
89		.name	= "ls1x-gpio",
90	},
91};
92
93module_platform_driver(ls1x_gpio_driver);
94
95MODULE_AUTHOR("Kelvin Cheung <keguang.zhang@gmail.com>");
96MODULE_DESCRIPTION("Loongson1 GPIO driver");
97MODULE_LICENSE("GPL");