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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// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * GPIO Driver for Loongson 1 SoC
4 *
5 * Copyright (C) 2015-2023 Keguang Zhang <keguang.zhang@gmail.com>
6 */
7
8#include <linux/module.h>
9#include <linux/gpio/driver.h>
10#include <linux/platform_device.h>
11#include <linux/bitops.h>
12
13/* Loongson 1 GPIO Register Definitions */
14#define GPIO_CFG 0x0
15#define GPIO_DIR 0x10
16#define GPIO_DATA 0x20
17#define GPIO_OUTPUT 0x30
18
19struct ls1x_gpio_chip {
20 struct gpio_chip gc;
21 void __iomem *reg_base;
22};
23
24static int ls1x_gpio_request(struct gpio_chip *gc, unsigned int offset)
25{
26 struct ls1x_gpio_chip *ls1x_gc = gpiochip_get_data(gc);
27 unsigned long flags;
28
29 raw_spin_lock_irqsave(&gc->bgpio_lock, flags);
30 __raw_writel(__raw_readl(ls1x_gc->reg_base + GPIO_CFG) | BIT(offset),
31 ls1x_gc->reg_base + GPIO_CFG);
32 raw_spin_unlock_irqrestore(&gc->bgpio_lock, flags);
33
34 return 0;
35}
36
37static void ls1x_gpio_free(struct gpio_chip *gc, unsigned int offset)
38{
39 struct ls1x_gpio_chip *ls1x_gc = gpiochip_get_data(gc);
40 unsigned long flags;
41
42 raw_spin_lock_irqsave(&gc->bgpio_lock, flags);
43 __raw_writel(__raw_readl(ls1x_gc->reg_base + GPIO_CFG) & ~BIT(offset),
44 ls1x_gc->reg_base + GPIO_CFG);
45 raw_spin_unlock_irqrestore(&gc->bgpio_lock, flags);
46}
47
48static int ls1x_gpio_probe(struct platform_device *pdev)
49{
50 struct device *dev = &pdev->dev;
51 struct ls1x_gpio_chip *ls1x_gc;
52 int ret;
53
54 ls1x_gc = devm_kzalloc(dev, sizeof(*ls1x_gc), GFP_KERNEL);
55 if (!ls1x_gc)
56 return -ENOMEM;
57
58 ls1x_gc->reg_base = devm_platform_ioremap_resource(pdev, 0);
59 if (IS_ERR(ls1x_gc->reg_base))
60 return PTR_ERR(ls1x_gc->reg_base);
61
62 ret = bgpio_init(&ls1x_gc->gc, dev, 4, ls1x_gc->reg_base + GPIO_DATA,
63 ls1x_gc->reg_base + GPIO_OUTPUT, NULL,
64 NULL, ls1x_gc->reg_base + GPIO_DIR, 0);
65 if (ret)
66 goto err;
67
68 ls1x_gc->gc.owner = THIS_MODULE;
69 ls1x_gc->gc.request = ls1x_gpio_request;
70 ls1x_gc->gc.free = ls1x_gpio_free;
71 /*
72 * Clear ngpio to let gpiolib get the correct number
73 * by reading ngpios property
74 */
75 ls1x_gc->gc.ngpio = 0;
76
77 ret = devm_gpiochip_add_data(dev, &ls1x_gc->gc, ls1x_gc);
78 if (ret)
79 goto err;
80
81 platform_set_drvdata(pdev, ls1x_gc);
82
83 dev_info(dev, "GPIO controller registered with %d pins\n",
84 ls1x_gc->gc.ngpio);
85
86 return 0;
87err:
88 dev_err(dev, "failed to register GPIO controller\n");
89 return ret;
90}
91
92static const struct of_device_id ls1x_gpio_dt_ids[] = {
93 { .compatible = "loongson,ls1x-gpio" },
94 { /* sentinel */ }
95};
96MODULE_DEVICE_TABLE(of, ls1x_gpio_dt_ids);
97
98static struct platform_driver ls1x_gpio_driver = {
99 .probe = ls1x_gpio_probe,
100 .driver = {
101 .name = "ls1x-gpio",
102 .of_match_table = ls1x_gpio_dt_ids,
103 },
104};
105
106module_platform_driver(ls1x_gpio_driver);
107
108MODULE_AUTHOR("Keguang Zhang <keguang.zhang@gmail.com>");
109MODULE_DESCRIPTION("Loongson1 GPIO driver");
110MODULE_LICENSE("GPL");