1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
|
/*
* SYSCON GPIO driver
*
* Copyright (C) 2014 Alexander Shiyan <shc_work@mail.ru>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*/
#include <linux/err.h>
#include <linux/gpio.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/platform_device.h>
#include <linux/regmap.h>
#include <linux/mfd/syscon.h>
#define GPIO_SYSCON_FEAT_IN BIT(0)
#define GPIO_SYSCON_FEAT_OUT BIT(1)
#define GPIO_SYSCON_FEAT_DIR BIT(2)
/* SYSCON driver is designed to use 32-bit wide registers */
#define SYSCON_REG_SIZE (4)
#define SYSCON_REG_BITS (SYSCON_REG_SIZE * 8)
/**
* struct syscon_gpio_data - Configuration for the device.
* compatible: SYSCON driver compatible string.
* flags: Set of GPIO_SYSCON_FEAT_ flags:
* GPIO_SYSCON_FEAT_IN: GPIOs supports input,
* GPIO_SYSCON_FEAT_OUT: GPIOs supports output,
* GPIO_SYSCON_FEAT_DIR: GPIOs supports switch direction.
* bit_count: Number of bits used as GPIOs.
* dat_bit_offset: Offset (in bits) to the first GPIO bit.
* dir_bit_offset: Optional offset (in bits) to the first bit to switch
* GPIO direction (Used with GPIO_SYSCON_FEAT_DIR flag).
* set: HW specific callback to assigns output value
* for signal "offset"
*/
struct syscon_gpio_data {
const char *compatible;
unsigned int flags;
unsigned int bit_count;
unsigned int dat_bit_offset;
unsigned int dir_bit_offset;
void (*set)(struct gpio_chip *chip,
unsigned offset, int value);
};
struct syscon_gpio_priv {
struct gpio_chip chip;
struct regmap *syscon;
const struct syscon_gpio_data *data;
u32 dreg_offset;
u32 dir_reg_offset;
};
static inline struct syscon_gpio_priv *to_syscon_gpio(struct gpio_chip *chip)
{
return container_of(chip, struct syscon_gpio_priv, chip);
}
static int syscon_gpio_get(struct gpio_chip *chip, unsigned offset)
{
struct syscon_gpio_priv *priv = to_syscon_gpio(chip);
unsigned int val, offs;
int ret;
offs = priv->dreg_offset + priv->data->dat_bit_offset + offset;
ret = regmap_read(priv->syscon,
(offs / SYSCON_REG_BITS) * SYSCON_REG_SIZE, &val);
if (ret)
return ret;
return !!(val & BIT(offs % SYSCON_REG_BITS));
}
static void syscon_gpio_set(struct gpio_chip *chip, unsigned offset, int val)
{
struct syscon_gpio_priv *priv = to_syscon_gpio(chip);
unsigned int offs;
offs = priv->dreg_offset + priv->data->dat_bit_offset + offset;
regmap_update_bits(priv->syscon,
(offs / SYSCON_REG_BITS) * SYSCON_REG_SIZE,
BIT(offs % SYSCON_REG_BITS),
val ? BIT(offs % SYSCON_REG_BITS) : 0);
}
static int syscon_gpio_dir_in(struct gpio_chip *chip, unsigned offset)
{
struct syscon_gpio_priv *priv = to_syscon_gpio(chip);
if (priv->data->flags & GPIO_SYSCON_FEAT_DIR) {
unsigned int offs;
offs = priv->dir_reg_offset +
priv->data->dir_bit_offset + offset;
regmap_update_bits(priv->syscon,
(offs / SYSCON_REG_BITS) * SYSCON_REG_SIZE,
BIT(offs % SYSCON_REG_BITS), 0);
}
return 0;
}
static int syscon_gpio_dir_out(struct gpio_chip *chip, unsigned offset, int val)
{
struct syscon_gpio_priv *priv = to_syscon_gpio(chip);
if (priv->data->flags & GPIO_SYSCON_FEAT_DIR) {
unsigned int offs;
offs = priv->dir_reg_offset +
priv->data->dir_bit_offset + offset;
regmap_update_bits(priv->syscon,
(offs / SYSCON_REG_BITS) * SYSCON_REG_SIZE,
BIT(offs % SYSCON_REG_BITS),
BIT(offs % SYSCON_REG_BITS));
}
priv->data->set(chip, offset, val);
return 0;
}
static const struct syscon_gpio_data clps711x_mctrl_gpio = {
/* ARM CLPS711X SYSFLG1 Bits 8-10 */
.compatible = "cirrus,clps711x-syscon1",
.flags = GPIO_SYSCON_FEAT_IN,
.bit_count = 3,
.dat_bit_offset = 0x40 * 8 + 8,
};
#define KEYSTONE_LOCK_BIT BIT(0)
static void keystone_gpio_set(struct gpio_chip *chip, unsigned offset, int val)
{
struct syscon_gpio_priv *priv = to_syscon_gpio(chip);
unsigned int offs;
int ret;
offs = priv->dreg_offset + priv->data->dat_bit_offset + offset;
if (!val)
return;
ret = regmap_update_bits(
priv->syscon,
(offs / SYSCON_REG_BITS) * SYSCON_REG_SIZE,
BIT(offs % SYSCON_REG_BITS) | KEYSTONE_LOCK_BIT,
BIT(offs % SYSCON_REG_BITS) | KEYSTONE_LOCK_BIT);
if (ret < 0)
dev_err(chip->dev, "gpio write failed ret(%d)\n", ret);
}
static const struct syscon_gpio_data keystone_dsp_gpio = {
/* ARM Keystone 2 */
.compatible = NULL,
.flags = GPIO_SYSCON_FEAT_OUT,
.bit_count = 28,
.dat_bit_offset = 4,
.set = keystone_gpio_set,
};
static const struct of_device_id syscon_gpio_ids[] = {
{
.compatible = "cirrus,clps711x-mctrl-gpio",
.data = &clps711x_mctrl_gpio,
},
{
.compatible = "ti,keystone-dsp-gpio",
.data = &keystone_dsp_gpio,
},
{ }
};
MODULE_DEVICE_TABLE(of, syscon_gpio_ids);
static int syscon_gpio_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
const struct of_device_id *of_id;
struct syscon_gpio_priv *priv;
struct device_node *np = dev->of_node;
int ret;
of_id = of_match_device(syscon_gpio_ids, dev);
if (!of_id)
return -ENODEV;
priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
if (!priv)
return -ENOMEM;
priv->data = of_id->data;
if (priv->data->compatible) {
priv->syscon = syscon_regmap_lookup_by_compatible(
priv->data->compatible);
if (IS_ERR(priv->syscon))
return PTR_ERR(priv->syscon);
} else {
priv->syscon =
syscon_regmap_lookup_by_phandle(np, "gpio,syscon-dev");
if (IS_ERR(priv->syscon))
return PTR_ERR(priv->syscon);
ret = of_property_read_u32_index(np, "gpio,syscon-dev", 1,
&priv->dreg_offset);
if (ret)
dev_err(dev, "can't read the data register offset!\n");
priv->dreg_offset <<= 3;
ret = of_property_read_u32_index(np, "gpio,syscon-dev", 2,
&priv->dir_reg_offset);
if (ret)
dev_dbg(dev, "can't read the dir register offset!\n");
priv->dir_reg_offset <<= 3;
}
priv->chip.dev = dev;
priv->chip.owner = THIS_MODULE;
priv->chip.label = dev_name(dev);
priv->chip.base = -1;
priv->chip.ngpio = priv->data->bit_count;
priv->chip.get = syscon_gpio_get;
if (priv->data->flags & GPIO_SYSCON_FEAT_IN)
priv->chip.direction_input = syscon_gpio_dir_in;
if (priv->data->flags & GPIO_SYSCON_FEAT_OUT) {
priv->chip.set = priv->data->set ? : syscon_gpio_set;
priv->chip.direction_output = syscon_gpio_dir_out;
}
platform_set_drvdata(pdev, priv);
return gpiochip_add(&priv->chip);
}
static int syscon_gpio_remove(struct platform_device *pdev)
{
struct syscon_gpio_priv *priv = platform_get_drvdata(pdev);
gpiochip_remove(&priv->chip);
return 0;
}
static struct platform_driver syscon_gpio_driver = {
.driver = {
.name = "gpio-syscon",
.of_match_table = syscon_gpio_ids,
},
.probe = syscon_gpio_probe,
.remove = syscon_gpio_remove,
};
module_platform_driver(syscon_gpio_driver);
MODULE_AUTHOR("Alexander Shiyan <shc_work@mail.ru>");
MODULE_DESCRIPTION("SYSCON GPIO driver");
MODULE_LICENSE("GPL");
|
