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
|
/*
* RDC321x GPIO driver
*
* Copyright (C) 2008, Volker Weiss <dev@tintuc.de>
* Copyright (C) 2007-2010 Florian Fainelli <florian@openwrt.org>
*
* 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.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*
*/
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/spinlock.h>
#include <linux/platform_device.h>
#include <linux/pci.h>
#include <linux/gpio.h>
#include <linux/mfd/rdc321x.h>
#include <linux/slab.h>
struct rdc321x_gpio {
spinlock_t lock;
struct pci_dev *sb_pdev;
u32 data_reg[2];
int reg1_ctrl_base;
int reg1_data_base;
int reg2_ctrl_base;
int reg2_data_base;
struct gpio_chip chip;
};
/* read GPIO pin */
static int rdc_gpio_get_value(struct gpio_chip *chip, unsigned gpio)
{
struct rdc321x_gpio *gpch;
u32 value = 0;
int reg;
gpch = container_of(chip, struct rdc321x_gpio, chip);
reg = gpio < 32 ? gpch->reg1_data_base : gpch->reg2_data_base;
spin_lock(&gpch->lock);
pci_write_config_dword(gpch->sb_pdev, reg,
gpch->data_reg[gpio < 32 ? 0 : 1]);
pci_read_config_dword(gpch->sb_pdev, reg, &value);
spin_unlock(&gpch->lock);
return (1 << (gpio & 0x1f)) & value ? 1 : 0;
}
static void rdc_gpio_set_value_impl(struct gpio_chip *chip,
unsigned gpio, int value)
{
struct rdc321x_gpio *gpch;
int reg = (gpio < 32) ? 0 : 1;
gpch = container_of(chip, struct rdc321x_gpio, chip);
if (value)
gpch->data_reg[reg] |= 1 << (gpio & 0x1f);
else
gpch->data_reg[reg] &= ~(1 << (gpio & 0x1f));
pci_write_config_dword(gpch->sb_pdev,
reg ? gpch->reg2_data_base : gpch->reg1_data_base,
gpch->data_reg[reg]);
}
/* set GPIO pin to value */
static void rdc_gpio_set_value(struct gpio_chip *chip,
unsigned gpio, int value)
{
struct rdc321x_gpio *gpch;
gpch = container_of(chip, struct rdc321x_gpio, chip);
spin_lock(&gpch->lock);
rdc_gpio_set_value_impl(chip, gpio, value);
spin_unlock(&gpch->lock);
}
static int rdc_gpio_config(struct gpio_chip *chip,
unsigned gpio, int value)
{
struct rdc321x_gpio *gpch;
int err;
u32 reg;
gpch = container_of(chip, struct rdc321x_gpio, chip);
spin_lock(&gpch->lock);
err = pci_read_config_dword(gpch->sb_pdev, gpio < 32 ?
gpch->reg1_ctrl_base : gpch->reg2_ctrl_base, ®);
if (err)
goto unlock;
reg |= 1 << (gpio & 0x1f);
err = pci_write_config_dword(gpch->sb_pdev, gpio < 32 ?
gpch->reg1_ctrl_base : gpch->reg2_ctrl_base, reg);
if (err)
goto unlock;
rdc_gpio_set_value_impl(chip, gpio, value);
unlock:
spin_unlock(&gpch->lock);
return err;
}
/* configure GPIO pin as input */
static int rdc_gpio_direction_input(struct gpio_chip *chip, unsigned gpio)
{
return rdc_gpio_config(chip, gpio, 1);
}
/*
* Cache the initial value of both GPIO data registers
*/
static int rdc321x_gpio_probe(struct platform_device *pdev)
{
int err;
struct resource *r;
struct rdc321x_gpio *rdc321x_gpio_dev;
struct rdc321x_gpio_pdata *pdata;
pdata = pdev->dev.platform_data;
if (!pdata) {
dev_err(&pdev->dev, "no platform data supplied\n");
return -ENODEV;
}
rdc321x_gpio_dev = kzalloc(sizeof(struct rdc321x_gpio), GFP_KERNEL);
if (!rdc321x_gpio_dev) {
dev_err(&pdev->dev, "failed to allocate private data\n");
return -ENOMEM;
}
r = platform_get_resource_byname(pdev, IORESOURCE_IO, "gpio-reg1");
if (!r) {
dev_err(&pdev->dev, "failed to get gpio-reg1 resource\n");
err = -ENODEV;
goto out_free;
}
spin_lock_init(&rdc321x_gpio_dev->lock);
rdc321x_gpio_dev->sb_pdev = pdata->sb_pdev;
rdc321x_gpio_dev->reg1_ctrl_base = r->start;
rdc321x_gpio_dev->reg1_data_base = r->start + 0x4;
r = platform_get_resource_byname(pdev, IORESOURCE_IO, "gpio-reg2");
if (!r) {
dev_err(&pdev->dev, "failed to get gpio-reg2 resource\n");
err = -ENODEV;
goto out_free;
}
rdc321x_gpio_dev->reg2_ctrl_base = r->start;
rdc321x_gpio_dev->reg2_data_base = r->start + 0x4;
rdc321x_gpio_dev->chip.label = "rdc321x-gpio";
rdc321x_gpio_dev->chip.owner = THIS_MODULE;
rdc321x_gpio_dev->chip.direction_input = rdc_gpio_direction_input;
rdc321x_gpio_dev->chip.direction_output = rdc_gpio_config;
rdc321x_gpio_dev->chip.get = rdc_gpio_get_value;
rdc321x_gpio_dev->chip.set = rdc_gpio_set_value;
rdc321x_gpio_dev->chip.base = 0;
rdc321x_gpio_dev->chip.ngpio = pdata->max_gpios;
platform_set_drvdata(pdev, rdc321x_gpio_dev);
/* This might not be, what others (BIOS, bootloader, etc.)
wrote to these registers before, but it's a good guess. Still
better than just using 0xffffffff. */
err = pci_read_config_dword(rdc321x_gpio_dev->sb_pdev,
rdc321x_gpio_dev->reg1_data_base,
&rdc321x_gpio_dev->data_reg[0]);
if (err)
goto out_drvdata;
err = pci_read_config_dword(rdc321x_gpio_dev->sb_pdev,
rdc321x_gpio_dev->reg2_data_base,
&rdc321x_gpio_dev->data_reg[1]);
if (err)
goto out_drvdata;
dev_info(&pdev->dev, "registering %d GPIOs\n",
rdc321x_gpio_dev->chip.ngpio);
return gpiochip_add(&rdc321x_gpio_dev->chip);
out_drvdata:
platform_set_drvdata(pdev, NULL);
out_free:
kfree(rdc321x_gpio_dev);
return err;
}
static int __devexit rdc321x_gpio_remove(struct platform_device *pdev)
{
int ret;
struct rdc321x_gpio *rdc321x_gpio_dev = platform_get_drvdata(pdev);
ret = gpiochip_remove(&rdc321x_gpio_dev->chip);
if (ret)
dev_err(&pdev->dev, "failed to unregister chip\n");
kfree(rdc321x_gpio_dev);
platform_set_drvdata(pdev, NULL);
return ret;
}
static struct platform_driver rdc321x_gpio_driver = {
.driver.name = "rdc321x-gpio",
.driver.owner = THIS_MODULE,
.probe = rdc321x_gpio_probe,
.remove = rdc321x_gpio_remove,
};
module_platform_driver(rdc321x_gpio_driver);
MODULE_AUTHOR("Florian Fainelli <florian@openwrt.org>");
MODULE_DESCRIPTION("RDC321x GPIO driver");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:rdc321x-gpio");
|
