blob: 0763655cca6ccc1ffd6b46f6cb0261a6fa31e9fc [file] [log] [blame]
Alexander Shiyanaf0a33e2014-10-03 11:31:57 +04001/*
2 * 74xx MMIO GPIO driver
3 *
4 * Copyright (C) 2014 Alexander Shiyan <shc_work@mail.ru>
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 */
11
12#include <linux/err.h>
13#include <linux/gpio.h>
14#include <linux/module.h>
15#include <linux/of_device.h>
16#include <linux/basic_mmio_gpio.h>
17#include <linux/platform_device.h>
18
19#define MMIO_74XX_DIR_IN (0 << 8)
20#define MMIO_74XX_DIR_OUT (1 << 8)
21#define MMIO_74XX_BIT_CNT(x) ((x) & 0xff)
22
23struct mmio_74xx_gpio_priv {
24 struct bgpio_chip bgc;
25 unsigned flags;
26};
27
28static const struct of_device_id mmio_74xx_gpio_ids[] = {
29 {
30 .compatible = "ti,741g125",
31 .data = (const void *)(MMIO_74XX_DIR_IN | 1),
32 },
33 {
34 .compatible = "ti,742g125",
35 .data = (const void *)(MMIO_74XX_DIR_IN | 2),
36 },
37 {
38 .compatible = "ti,74125",
39 .data = (const void *)(MMIO_74XX_DIR_IN | 4),
40 },
41 {
42 .compatible = "ti,74365",
43 .data = (const void *)(MMIO_74XX_DIR_IN | 6),
44 },
45 {
46 .compatible = "ti,74244",
47 .data = (const void *)(MMIO_74XX_DIR_IN | 8),
48 },
49 {
50 .compatible = "ti,741624",
51 .data = (const void *)(MMIO_74XX_DIR_IN | 16),
52 },
53 {
54 .compatible = "ti,741g74",
55 .data = (const void *)(MMIO_74XX_DIR_OUT | 1),
56 },
57 {
58 .compatible = "ti,7474",
59 .data = (const void *)(MMIO_74XX_DIR_OUT | 2),
60 },
61 {
62 .compatible = "ti,74175",
63 .data = (const void *)(MMIO_74XX_DIR_OUT | 4),
64 },
65 {
66 .compatible = "ti,74174",
67 .data = (const void *)(MMIO_74XX_DIR_OUT | 6),
68 },
69 {
70 .compatible = "ti,74273",
71 .data = (const void *)(MMIO_74XX_DIR_OUT | 8),
72 },
73 {
74 .compatible = "ti,7416374",
75 .data = (const void *)(MMIO_74XX_DIR_OUT | 16),
76 },
77 { }
78};
79MODULE_DEVICE_TABLE(of, mmio_74xx_gpio_ids);
80
81static inline struct mmio_74xx_gpio_priv *to_74xx_gpio(struct gpio_chip *gc)
82{
83 struct bgpio_chip *bgc = to_bgpio_chip(gc);
84
85 return container_of(bgc, struct mmio_74xx_gpio_priv, bgc);
86}
87
88static int mmio_74xx_get_direction(struct gpio_chip *gc, unsigned offset)
89{
90 struct mmio_74xx_gpio_priv *priv = to_74xx_gpio(gc);
91
92 return (priv->flags & MMIO_74XX_DIR_OUT) ? GPIOF_DIR_OUT : GPIOF_DIR_IN;
93}
94
95static int mmio_74xx_dir_in(struct gpio_chip *gc, unsigned int gpio)
96{
97 struct mmio_74xx_gpio_priv *priv = to_74xx_gpio(gc);
98
99 return (priv->flags & MMIO_74XX_DIR_OUT) ? -ENOTSUPP : 0;
100}
101
102static int mmio_74xx_dir_out(struct gpio_chip *gc, unsigned int gpio, int val)
103{
104 struct mmio_74xx_gpio_priv *priv = to_74xx_gpio(gc);
105
106 if (priv->flags & MMIO_74XX_DIR_OUT) {
107 gc->set(gc, gpio, val);
108 return 0;
109 }
110
111 return -ENOTSUPP;
112}
113
114static int mmio_74xx_gpio_probe(struct platform_device *pdev)
115{
116 const struct of_device_id *of_id =
117 of_match_device(mmio_74xx_gpio_ids, &pdev->dev);
118 struct mmio_74xx_gpio_priv *priv;
119 struct resource *res;
120 void __iomem *dat;
121 int err;
122
123 priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
124 if (!priv)
125 return -ENOMEM;
126
127 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
128 dat = devm_ioremap_resource(&pdev->dev, res);
129 if (IS_ERR(dat))
130 return PTR_ERR(dat);
131
132 priv->flags = (unsigned)of_id->data;
133
134 err = bgpio_init(&priv->bgc, &pdev->dev,
135 DIV_ROUND_UP(MMIO_74XX_BIT_CNT(priv->flags), 8),
136 dat, NULL, NULL, NULL, NULL, 0);
137 if (err)
138 return err;
139
140 priv->bgc.gc.direction_input = mmio_74xx_dir_in;
141 priv->bgc.gc.direction_output = mmio_74xx_dir_out;
142 priv->bgc.gc.get_direction = mmio_74xx_get_direction;
143 priv->bgc.gc.ngpio = MMIO_74XX_BIT_CNT(priv->flags);
144 priv->bgc.gc.owner = THIS_MODULE;
145
146 platform_set_drvdata(pdev, priv);
147
148 return gpiochip_add(&priv->bgc.gc);
149}
150
151static int mmio_74xx_gpio_remove(struct platform_device *pdev)
152{
153 struct mmio_74xx_gpio_priv *priv = platform_get_drvdata(pdev);
154
155 return bgpio_remove(&priv->bgc);
156}
157
158static struct platform_driver mmio_74xx_gpio_driver = {
159 .driver = {
160 .name = "74xx-mmio-gpio",
161 .of_match_table = mmio_74xx_gpio_ids,
162 },
163 .probe = mmio_74xx_gpio_probe,
164 .remove = mmio_74xx_gpio_remove,
165};
166module_platform_driver(mmio_74xx_gpio_driver);
167
168MODULE_LICENSE("GPL");
169MODULE_AUTHOR("Alexander Shiyan <shc_work@mail.ru>");
170MODULE_DESCRIPTION("74xx MMIO GPIO driver");