Root/drivers/gpio/gpio-rdc321x.c

1/*
2 * RDC321x GPIO driver
3 *
4 * Copyright (C) 2008, Volker Weiss <dev@tintuc.de>
5 * Copyright (C) 2007-2010 Florian Fainelli <florian@openwrt.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
10 * (at your option) any later version.
11 *
12 * This program is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
16 *
17 * You should have received a copy of the GNU General Public License
18 * along with this program; if not, write to the Free Software
19 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
20 *
21 */
22#include <linux/module.h>
23#include <linux/kernel.h>
24#include <linux/init.h>
25#include <linux/spinlock.h>
26#include <linux/platform_device.h>
27#include <linux/pci.h>
28#include <linux/gpio.h>
29#include <linux/mfd/rdc321x.h>
30#include <linux/slab.h>
31
32struct rdc321x_gpio {
33    spinlock_t lock;
34    struct pci_dev *sb_pdev;
35    u32 data_reg[2];
36    int reg1_ctrl_base;
37    int reg1_data_base;
38    int reg2_ctrl_base;
39    int reg2_data_base;
40    struct gpio_chip chip;
41};
42
43/* read GPIO pin */
44static int rdc_gpio_get_value(struct gpio_chip *chip, unsigned gpio)
45{
46    struct rdc321x_gpio *gpch;
47    u32 value = 0;
48    int reg;
49
50    gpch = container_of(chip, struct rdc321x_gpio, chip);
51    reg = gpio < 32 ? gpch->reg1_data_base : gpch->reg2_data_base;
52
53    spin_lock(&gpch->lock);
54    pci_write_config_dword(gpch->sb_pdev, reg,
55                    gpch->data_reg[gpio < 32 ? 0 : 1]);
56    pci_read_config_dword(gpch->sb_pdev, reg, &value);
57    spin_unlock(&gpch->lock);
58
59    return (1 << (gpio & 0x1f)) & value ? 1 : 0;
60}
61
62static void rdc_gpio_set_value_impl(struct gpio_chip *chip,
63                unsigned gpio, int value)
64{
65    struct rdc321x_gpio *gpch;
66    int reg = (gpio < 32) ? 0 : 1;
67
68    gpch = container_of(chip, struct rdc321x_gpio, chip);
69
70    if (value)
71        gpch->data_reg[reg] |= 1 << (gpio & 0x1f);
72    else
73        gpch->data_reg[reg] &= ~(1 << (gpio & 0x1f));
74
75    pci_write_config_dword(gpch->sb_pdev,
76            reg ? gpch->reg2_data_base : gpch->reg1_data_base,
77            gpch->data_reg[reg]);
78}
79
80/* set GPIO pin to value */
81static void rdc_gpio_set_value(struct gpio_chip *chip,
82                unsigned gpio, int value)
83{
84    struct rdc321x_gpio *gpch;
85
86    gpch = container_of(chip, struct rdc321x_gpio, chip);
87    spin_lock(&gpch->lock);
88    rdc_gpio_set_value_impl(chip, gpio, value);
89    spin_unlock(&gpch->lock);
90}
91
92static int rdc_gpio_config(struct gpio_chip *chip,
93                unsigned gpio, int value)
94{
95    struct rdc321x_gpio *gpch;
96    int err;
97    u32 reg;
98
99    gpch = container_of(chip, struct rdc321x_gpio, chip);
100
101    spin_lock(&gpch->lock);
102    err = pci_read_config_dword(gpch->sb_pdev, gpio < 32 ?
103            gpch->reg1_ctrl_base : gpch->reg2_ctrl_base, &reg);
104    if (err)
105        goto unlock;
106
107    reg |= 1 << (gpio & 0x1f);
108
109    err = pci_write_config_dword(gpch->sb_pdev, gpio < 32 ?
110            gpch->reg1_ctrl_base : gpch->reg2_ctrl_base, reg);
111    if (err)
112        goto unlock;
113
114    rdc_gpio_set_value_impl(chip, gpio, value);
115
116unlock:
117    spin_unlock(&gpch->lock);
118
119    return err;
120}
121
122/* configure GPIO pin as input */
123static int rdc_gpio_direction_input(struct gpio_chip *chip, unsigned gpio)
124{
125    return rdc_gpio_config(chip, gpio, 1);
126}
127
128/*
129 * Cache the initial value of both GPIO data registers
130 */
131static int __devinit rdc321x_gpio_probe(struct platform_device *pdev)
132{
133    int err;
134    struct resource *r;
135    struct rdc321x_gpio *rdc321x_gpio_dev;
136    struct rdc321x_gpio_pdata *pdata;
137
138    pdata = pdev->dev.platform_data;
139    if (!pdata) {
140        dev_err(&pdev->dev, "no platform data supplied\n");
141        return -ENODEV;
142    }
143
144    rdc321x_gpio_dev = kzalloc(sizeof(struct rdc321x_gpio), GFP_KERNEL);
145    if (!rdc321x_gpio_dev) {
146        dev_err(&pdev->dev, "failed to allocate private data\n");
147        return -ENOMEM;
148    }
149
150    r = platform_get_resource_byname(pdev, IORESOURCE_IO, "gpio-reg1");
151    if (!r) {
152        dev_err(&pdev->dev, "failed to get gpio-reg1 resource\n");
153        err = -ENODEV;
154        goto out_free;
155    }
156
157    spin_lock_init(&rdc321x_gpio_dev->lock);
158    rdc321x_gpio_dev->sb_pdev = pdata->sb_pdev;
159    rdc321x_gpio_dev->reg1_ctrl_base = r->start;
160    rdc321x_gpio_dev->reg1_data_base = r->start + 0x4;
161
162    r = platform_get_resource_byname(pdev, IORESOURCE_IO, "gpio-reg2");
163    if (!r) {
164        dev_err(&pdev->dev, "failed to get gpio-reg2 resource\n");
165        err = -ENODEV;
166        goto out_free;
167    }
168
169    rdc321x_gpio_dev->reg2_ctrl_base = r->start;
170    rdc321x_gpio_dev->reg2_data_base = r->start + 0x4;
171
172    rdc321x_gpio_dev->chip.label = "rdc321x-gpio";
173    rdc321x_gpio_dev->chip.owner = THIS_MODULE;
174    rdc321x_gpio_dev->chip.direction_input = rdc_gpio_direction_input;
175    rdc321x_gpio_dev->chip.direction_output = rdc_gpio_config;
176    rdc321x_gpio_dev->chip.get = rdc_gpio_get_value;
177    rdc321x_gpio_dev->chip.set = rdc_gpio_set_value;
178    rdc321x_gpio_dev->chip.base = 0;
179    rdc321x_gpio_dev->chip.ngpio = pdata->max_gpios;
180
181    platform_set_drvdata(pdev, rdc321x_gpio_dev);
182
183    /* This might not be, what others (BIOS, bootloader, etc.)
184       wrote to these registers before, but it's a good guess. Still
185       better than just using 0xffffffff. */
186    err = pci_read_config_dword(rdc321x_gpio_dev->sb_pdev,
187                    rdc321x_gpio_dev->reg1_data_base,
188                    &rdc321x_gpio_dev->data_reg[0]);
189    if (err)
190        goto out_drvdata;
191
192    err = pci_read_config_dword(rdc321x_gpio_dev->sb_pdev,
193                    rdc321x_gpio_dev->reg2_data_base,
194                    &rdc321x_gpio_dev->data_reg[1]);
195    if (err)
196        goto out_drvdata;
197
198    dev_info(&pdev->dev, "registering %d GPIOs\n",
199                    rdc321x_gpio_dev->chip.ngpio);
200    return gpiochip_add(&rdc321x_gpio_dev->chip);
201
202out_drvdata:
203    platform_set_drvdata(pdev, NULL);
204out_free:
205    kfree(rdc321x_gpio_dev);
206    return err;
207}
208
209static int __devexit rdc321x_gpio_remove(struct platform_device *pdev)
210{
211    int ret;
212    struct rdc321x_gpio *rdc321x_gpio_dev = platform_get_drvdata(pdev);
213
214    ret = gpiochip_remove(&rdc321x_gpio_dev->chip);
215    if (ret)
216        dev_err(&pdev->dev, "failed to unregister chip\n");
217
218    kfree(rdc321x_gpio_dev);
219    platform_set_drvdata(pdev, NULL);
220
221    return ret;
222}
223
224static struct platform_driver rdc321x_gpio_driver = {
225    .driver.name = "rdc321x-gpio",
226    .driver.owner = THIS_MODULE,
227    .probe = rdc321x_gpio_probe,
228    .remove = __devexit_p(rdc321x_gpio_remove),
229};
230
231module_platform_driver(rdc321x_gpio_driver);
232
233MODULE_AUTHOR("Florian Fainelli <florian@openwrt.org>");
234MODULE_DESCRIPTION("RDC321x GPIO driver");
235MODULE_LICENSE("GPL");
236MODULE_ALIAS("platform:rdc321x-gpio");
237

Archive Download this file

Branches:
ben-wpan
ben-wpan-stefan
javiroman/ks7010
jz-2.6.34
jz-2.6.34-rc5
jz-2.6.34-rc6
jz-2.6.34-rc7
jz-2.6.35
jz-2.6.36
jz-2.6.37
jz-2.6.38
jz-2.6.39
jz-3.0
jz-3.1
jz-3.11
jz-3.12
jz-3.13
jz-3.15
jz-3.16
jz-3.18-dt
jz-3.2
jz-3.3
jz-3.4
jz-3.5
jz-3.6
jz-3.6-rc2-pwm
jz-3.9
jz-3.9-clk
jz-3.9-rc8
jz47xx
jz47xx-2.6.38
master

Tags:
od-2011-09-04
od-2011-09-18
v2.6.34-rc5
v2.6.34-rc6
v2.6.34-rc7
v3.9



interactive