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1/*
2 * arch/arm/plat-iop/gpio.c
3 * GPIO handling for Intel IOP3xx processors.
4 *
5 * Copyright (C) 2006 Lennert Buytenhek <buytenh@wantstofly.org>
6 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation; either version 2 of the License, or (at
10 * your option) any later version.
11 */
12
13#include <linux/device.h>
14#include <linux/init.h>
15#include <linux/types.h>
16#include <linux/errno.h>
17#include <linux/gpio.h>
18#include <linux/export.h>
19#include <linux/platform_device.h>
20#include <linux/bitops.h>
21#include <linux/io.h>
22
23#define IOP3XX_N_GPIOS 8
24
25#define GPIO_IN 0
26#define GPIO_OUT 1
27#define GPIO_LOW 0
28#define GPIO_HIGH 1
29
30/* Memory base offset */
31static void __iomem *base;
32
33#define IOP3XX_GPIO_REG(reg) (base + (reg))
34#define IOP3XX_GPOE IOP3XX_GPIO_REG(0x0000)
35#define IOP3XX_GPID IOP3XX_GPIO_REG(0x0004)
36#define IOP3XX_GPOD IOP3XX_GPIO_REG(0x0008)
37
38static void gpio_line_config(int line, int direction)
39{
40 unsigned long flags;
41 u32 val;
42
43 local_irq_save(flags);
44 val = readl(IOP3XX_GPOE);
45 if (direction == GPIO_IN) {
46 val |= BIT(line);
47 } else if (direction == GPIO_OUT) {
48 val &= ~BIT(line);
49 }
50 writel(val, IOP3XX_GPOE);
51 local_irq_restore(flags);
52}
53
54static int gpio_line_get(int line)
55{
56 return !!(readl(IOP3XX_GPID) & BIT(line));
57}
58
59static void gpio_line_set(int line, int value)
60{
61 unsigned long flags;
62 u32 val;
63
64 local_irq_save(flags);
65 val = readl(IOP3XX_GPOD);
66 if (value == GPIO_LOW) {
67 val &= ~BIT(line);
68 } else if (value == GPIO_HIGH) {
69 val |= BIT(line);
70 }
71 writel(val, IOP3XX_GPOD);
72 local_irq_restore(flags);
73}
74
75static int iop3xx_gpio_direction_input(struct gpio_chip *chip, unsigned gpio)
76{
77 gpio_line_config(gpio, GPIO_IN);
78 return 0;
79}
80
81static int iop3xx_gpio_direction_output(struct gpio_chip *chip, unsigned gpio, int level)
82{
83 gpio_line_set(gpio, level);
84 gpio_line_config(gpio, GPIO_OUT);
85 return 0;
86}
87
88static int iop3xx_gpio_get_value(struct gpio_chip *chip, unsigned gpio)
89{
90 return gpio_line_get(gpio);
91}
92
93static void iop3xx_gpio_set_value(struct gpio_chip *chip, unsigned gpio, int value)
94{
95 gpio_line_set(gpio, value);
96}
97
98static struct gpio_chip iop3xx_chip = {
99 .label = "iop3xx",
100 .direction_input = iop3xx_gpio_direction_input,
101 .get = iop3xx_gpio_get_value,
102 .direction_output = iop3xx_gpio_direction_output,
103 .set = iop3xx_gpio_set_value,
104 .base = 0,
105 .ngpio = IOP3XX_N_GPIOS,
106};
107
108static int iop3xx_gpio_probe(struct platform_device *pdev)
109{
110 struct resource *res;
111
112 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
113 base = devm_ioremap_resource(&pdev->dev, res);
114 if (IS_ERR(base))
115 return PTR_ERR(base);
116
117 return gpiochip_add(&iop3xx_chip);
118}
119
120static struct platform_driver iop3xx_gpio_driver = {
121 .driver = {
122 .name = "gpio-iop",
123 .owner = THIS_MODULE,
124 },
125 .probe = iop3xx_gpio_probe,
126};
127
128static int __init iop3xx_gpio_init(void)
129{
130 return platform_driver_register(&iop3xx_gpio_driver);
131}
132arch_initcall(iop3xx_gpio_init);
1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * arch/arm/plat-iop/gpio.c
4 * GPIO handling for Intel IOP3xx processors.
5 *
6 * Copyright (C) 2006 Lennert Buytenhek <buytenh@wantstofly.org>
7 */
8
9#include <linux/err.h>
10#include <linux/module.h>
11#include <linux/gpio/driver.h>
12#include <linux/platform_device.h>
13
14#define IOP3XX_GPOE 0x0000
15#define IOP3XX_GPID 0x0004
16#define IOP3XX_GPOD 0x0008
17
18static int iop3xx_gpio_probe(struct platform_device *pdev)
19{
20 struct gpio_chip *gc;
21 void __iomem *base;
22 int err;
23
24 gc = devm_kzalloc(&pdev->dev, sizeof(*gc), GFP_KERNEL);
25 if (!gc)
26 return -ENOMEM;
27
28 base = devm_platform_ioremap_resource(pdev, 0);
29 if (IS_ERR(base))
30 return PTR_ERR(base);
31
32 err = bgpio_init(gc, &pdev->dev, 1, base + IOP3XX_GPID,
33 base + IOP3XX_GPOD, NULL, NULL, base + IOP3XX_GPOE, 0);
34 if (err)
35 return err;
36
37 gc->base = 0;
38 gc->owner = THIS_MODULE;
39 gc->label = "gpio-iop";
40
41 return devm_gpiochip_add_data(&pdev->dev, gc, NULL);
42}
43
44static struct platform_driver iop3xx_gpio_driver = {
45 .driver = {
46 .name = "gpio-iop",
47 },
48 .probe = iop3xx_gpio_probe,
49};
50
51static int __init iop3xx_gpio_init(void)
52{
53 return platform_driver_register(&iop3xx_gpio_driver);
54}
55arch_initcall(iop3xx_gpio_init);
56
57MODULE_DESCRIPTION("GPIO handling for Intel IOP3xx processors");
58MODULE_AUTHOR("Lennert Buytenhek <buytenh@wantstofly.org>");
59MODULE_LICENSE("GPL");