diff options
Diffstat (limited to 'drivers/gpio/rdc321x-gpio.c')
-rw-r--r-- | drivers/gpio/rdc321x-gpio.c | 246 |
1 files changed, 246 insertions, 0 deletions
diff --git a/drivers/gpio/rdc321x-gpio.c b/drivers/gpio/rdc321x-gpio.c new file mode 100644 index 000000000000..2762698e0204 --- /dev/null +++ b/drivers/gpio/rdc321x-gpio.c | |||
@@ -0,0 +1,246 @@ | |||
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 | |||
32 | struct 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 */ | ||
44 | static 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 | |||
62 | static 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 */ | ||
81 | static 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 | |||
92 | static 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, ®); | ||
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 | |||
116 | unlock: | ||
117 | spin_unlock(&gpch->lock); | ||
118 | |||
119 | return err; | ||
120 | } | ||
121 | |||
122 | /* configure GPIO pin as input */ | ||
123 | static 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 | */ | ||
131 | static 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.direction_input = rdc_gpio_direction_input; | ||
174 | rdc321x_gpio_dev->chip.direction_output = rdc_gpio_config; | ||
175 | rdc321x_gpio_dev->chip.get = rdc_gpio_get_value; | ||
176 | rdc321x_gpio_dev->chip.set = rdc_gpio_set_value; | ||
177 | rdc321x_gpio_dev->chip.base = 0; | ||
178 | rdc321x_gpio_dev->chip.ngpio = pdata->max_gpios; | ||
179 | |||
180 | platform_set_drvdata(pdev, rdc321x_gpio_dev); | ||
181 | |||
182 | /* This might not be, what others (BIOS, bootloader, etc.) | ||
183 | wrote to these registers before, but it's a good guess. Still | ||
184 | better than just using 0xffffffff. */ | ||
185 | err = pci_read_config_dword(rdc321x_gpio_dev->sb_pdev, | ||
186 | rdc321x_gpio_dev->reg1_data_base, | ||
187 | &rdc321x_gpio_dev->data_reg[0]); | ||
188 | if (err) | ||
189 | goto out_drvdata; | ||
190 | |||
191 | err = pci_read_config_dword(rdc321x_gpio_dev->sb_pdev, | ||
192 | rdc321x_gpio_dev->reg2_data_base, | ||
193 | &rdc321x_gpio_dev->data_reg[1]); | ||
194 | if (err) | ||
195 | goto out_drvdata; | ||
196 | |||
197 | dev_info(&pdev->dev, "registering %d GPIOs\n", | ||
198 | rdc321x_gpio_dev->chip.ngpio); | ||
199 | return gpiochip_add(&rdc321x_gpio_dev->chip); | ||
200 | |||
201 | out_drvdata: | ||
202 | platform_set_drvdata(pdev, NULL); | ||
203 | out_free: | ||
204 | kfree(rdc321x_gpio_dev); | ||
205 | return err; | ||
206 | } | ||
207 | |||
208 | static int __devexit rdc321x_gpio_remove(struct platform_device *pdev) | ||
209 | { | ||
210 | int ret; | ||
211 | struct rdc321x_gpio *rdc321x_gpio_dev = platform_get_drvdata(pdev); | ||
212 | |||
213 | ret = gpiochip_remove(&rdc321x_gpio_dev->chip); | ||
214 | if (ret) | ||
215 | dev_err(&pdev->dev, "failed to unregister chip\n"); | ||
216 | |||
217 | kfree(rdc321x_gpio_dev); | ||
218 | platform_set_drvdata(pdev, NULL); | ||
219 | |||
220 | return ret; | ||
221 | } | ||
222 | |||
223 | static struct platform_driver rdc321x_gpio_driver = { | ||
224 | .driver.name = "rdc321x-gpio", | ||
225 | .driver.owner = THIS_MODULE, | ||
226 | .probe = rdc321x_gpio_probe, | ||
227 | .remove = __devexit_p(rdc321x_gpio_remove), | ||
228 | }; | ||
229 | |||
230 | static int __init rdc321x_gpio_init(void) | ||
231 | { | ||
232 | return platform_driver_register(&rdc321x_gpio_driver); | ||
233 | } | ||
234 | |||
235 | static void __exit rdc321x_gpio_exit(void) | ||
236 | { | ||
237 | platform_driver_unregister(&rdc321x_gpio_driver); | ||
238 | } | ||
239 | |||
240 | module_init(rdc321x_gpio_init); | ||
241 | module_exit(rdc321x_gpio_exit); | ||
242 | |||
243 | MODULE_AUTHOR("Florian Fainelli <florian@openwrt.org>"); | ||
244 | MODULE_DESCRIPTION("RDC321x GPIO driver"); | ||
245 | MODULE_LICENSE("GPL"); | ||
246 | MODULE_ALIAS("platform:rdc321x-gpio"); | ||