blob: a9bda881935a82907ff0c5c753efee59b924cdf5 [file] [log] [blame]
Florian Fainelli9956d022010-03-21 01:06:09 +01001/*
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>
Andres Salomon46673ed2011-02-17 19:07:32 -080030#include <linux/mfd/core.h>
Tejun Heo374b72e2010-04-02 18:24:20 +020031#include <linux/slab.h>
Florian Fainelli9956d022010-03-21 01:06:09 +010032
33struct rdc321x_gpio {
34 spinlock_t lock;
35 struct pci_dev *sb_pdev;
36 u32 data_reg[2];
37 int reg1_ctrl_base;
38 int reg1_data_base;
39 int reg2_ctrl_base;
40 int reg2_data_base;
41 struct gpio_chip chip;
42};
43
44/* read GPIO pin */
45static int rdc_gpio_get_value(struct gpio_chip *chip, unsigned gpio)
46{
47 struct rdc321x_gpio *gpch;
48 u32 value = 0;
49 int reg;
50
51 gpch = container_of(chip, struct rdc321x_gpio, chip);
52 reg = gpio < 32 ? gpch->reg1_data_base : gpch->reg2_data_base;
53
54 spin_lock(&gpch->lock);
55 pci_write_config_dword(gpch->sb_pdev, reg,
56 gpch->data_reg[gpio < 32 ? 0 : 1]);
57 pci_read_config_dword(gpch->sb_pdev, reg, &value);
58 spin_unlock(&gpch->lock);
59
60 return (1 << (gpio & 0x1f)) & value ? 1 : 0;
61}
62
63static void rdc_gpio_set_value_impl(struct gpio_chip *chip,
64 unsigned gpio, int value)
65{
66 struct rdc321x_gpio *gpch;
67 int reg = (gpio < 32) ? 0 : 1;
68
69 gpch = container_of(chip, struct rdc321x_gpio, chip);
70
71 if (value)
72 gpch->data_reg[reg] |= 1 << (gpio & 0x1f);
73 else
74 gpch->data_reg[reg] &= ~(1 << (gpio & 0x1f));
75
76 pci_write_config_dword(gpch->sb_pdev,
Florian Fainelli75907a12010-05-16 12:02:18 +020077 reg ? gpch->reg2_data_base : gpch->reg1_data_base,
Florian Fainelli9956d022010-03-21 01:06:09 +010078 gpch->data_reg[reg]);
79}
80
81/* set GPIO pin to value */
82static void rdc_gpio_set_value(struct gpio_chip *chip,
83 unsigned gpio, int value)
84{
85 struct rdc321x_gpio *gpch;
86
87 gpch = container_of(chip, struct rdc321x_gpio, chip);
88 spin_lock(&gpch->lock);
89 rdc_gpio_set_value_impl(chip, gpio, value);
90 spin_unlock(&gpch->lock);
91}
92
93static int rdc_gpio_config(struct gpio_chip *chip,
94 unsigned gpio, int value)
95{
96 struct rdc321x_gpio *gpch;
97 int err;
98 u32 reg;
99
100 gpch = container_of(chip, struct rdc321x_gpio, chip);
101
102 spin_lock(&gpch->lock);
103 err = pci_read_config_dword(gpch->sb_pdev, gpio < 32 ?
104 gpch->reg1_ctrl_base : gpch->reg2_ctrl_base, &reg);
105 if (err)
106 goto unlock;
107
108 reg |= 1 << (gpio & 0x1f);
109
110 err = pci_write_config_dword(gpch->sb_pdev, gpio < 32 ?
111 gpch->reg1_ctrl_base : gpch->reg2_ctrl_base, reg);
112 if (err)
113 goto unlock;
114
115 rdc_gpio_set_value_impl(chip, gpio, value);
116
117unlock:
118 spin_unlock(&gpch->lock);
119
120 return err;
121}
122
123/* configure GPIO pin as input */
124static int rdc_gpio_direction_input(struct gpio_chip *chip, unsigned gpio)
125{
126 return rdc_gpio_config(chip, gpio, 1);
127}
128
129/*
130 * Cache the initial value of both GPIO data registers
131 */
132static int __devinit rdc321x_gpio_probe(struct platform_device *pdev)
133{
134 int err;
135 struct resource *r;
136 struct rdc321x_gpio *rdc321x_gpio_dev;
137 struct rdc321x_gpio_pdata *pdata;
138
Andres Salomon46673ed2011-02-17 19:07:32 -0800139 pdata = mfd_get_data(pdev);
Florian Fainelli9956d022010-03-21 01:06:09 +0100140 if (!pdata) {
141 dev_err(&pdev->dev, "no platform data supplied\n");
142 return -ENODEV;
143 }
144
145 rdc321x_gpio_dev = kzalloc(sizeof(struct rdc321x_gpio), GFP_KERNEL);
146 if (!rdc321x_gpio_dev) {
147 dev_err(&pdev->dev, "failed to allocate private data\n");
148 return -ENOMEM;
149 }
150
Florian Fainelli8deca39e2010-05-15 22:58:27 +0200151 r = platform_get_resource_byname(pdev, IORESOURCE_IO, "gpio-reg1");
Florian Fainelli9956d022010-03-21 01:06:09 +0100152 if (!r) {
153 dev_err(&pdev->dev, "failed to get gpio-reg1 resource\n");
154 err = -ENODEV;
155 goto out_free;
156 }
157
158 spin_lock_init(&rdc321x_gpio_dev->lock);
159 rdc321x_gpio_dev->sb_pdev = pdata->sb_pdev;
160 rdc321x_gpio_dev->reg1_ctrl_base = r->start;
161 rdc321x_gpio_dev->reg1_data_base = r->start + 0x4;
162
Florian Fainelli8deca39e2010-05-15 22:58:27 +0200163 r = platform_get_resource_byname(pdev, IORESOURCE_IO, "gpio-reg2");
Florian Fainelli9956d022010-03-21 01:06:09 +0100164 if (!r) {
165 dev_err(&pdev->dev, "failed to get gpio-reg2 resource\n");
166 err = -ENODEV;
167 goto out_free;
168 }
169
170 rdc321x_gpio_dev->reg2_ctrl_base = r->start;
171 rdc321x_gpio_dev->reg2_data_base = r->start + 0x4;
172
173 rdc321x_gpio_dev->chip.label = "rdc321x-gpio";
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
231static int __init rdc321x_gpio_init(void)
232{
233 return platform_driver_register(&rdc321x_gpio_driver);
234}
235
236static void __exit rdc321x_gpio_exit(void)
237{
238 platform_driver_unregister(&rdc321x_gpio_driver);
239}
240
241module_init(rdc321x_gpio_init);
242module_exit(rdc321x_gpio_exit);
243
244MODULE_AUTHOR("Florian Fainelli <florian@openwrt.org>");
245MODULE_DESCRIPTION("RDC321x GPIO driver");
246MODULE_LICENSE("GPL");
247MODULE_ALIAS("platform:rdc321x-gpio");