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14#include <linux/device.h>
15#include <linux/errno.h>
16#include <linux/module.h>
17#include <linux/io.h>
18#include <linux/of.h>
19#include <linux/of_address.h>
20#include <linux/of_gpio.h>
21#include <linux/slab.h>
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33int of_get_gpio_flags(struct device_node *np, int index,
34 enum of_gpio_flags *flags)
35{
36 int ret;
37 struct device_node *gpio_np;
38 struct gpio_chip *gc;
39 int size;
40 const void *gpio_spec;
41 const __be32 *gpio_cells;
42
43 ret = of_parse_phandles_with_args(np, "gpios", "#gpio-cells", index,
44 &gpio_np, &gpio_spec);
45 if (ret) {
46 pr_debug("%s: can't parse gpios property\n", __func__);
47 goto err0;
48 }
49
50 gc = of_node_to_gpiochip(gpio_np);
51 if (!gc) {
52 pr_debug("%s: gpio controller %s isn't registered\n",
53 np->full_name, gpio_np->full_name);
54 ret = -ENODEV;
55 goto err1;
56 }
57
58 gpio_cells = of_get_property(gpio_np, "#gpio-cells", &size);
59 if (!gpio_cells || size != sizeof(*gpio_cells) ||
60 be32_to_cpup(gpio_cells) != gc->of_gpio_n_cells) {
61 pr_debug("%s: wrong #gpio-cells for %s\n",
62 np->full_name, gpio_np->full_name);
63 ret = -EINVAL;
64 goto err1;
65 }
66
67
68 if (flags)
69 *flags = 0;
70
71 ret = gc->of_xlate(gc, np, gpio_spec, flags);
72 if (ret < 0)
73 goto err1;
74
75 ret += gc->base;
76err1:
77 of_node_put(gpio_np);
78err0:
79 pr_debug("%s exited with status %d\n", __func__, ret);
80 return ret;
81}
82EXPORT_SYMBOL(of_get_gpio_flags);
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100unsigned int of_gpio_count(struct device_node *np)
101{
102 unsigned int cnt = 0;
103
104 do {
105 int ret;
106
107 ret = of_parse_phandles_with_args(np, "gpios", "#gpio-cells",
108 cnt, NULL, NULL);
109
110 if (ret < 0 && ret != -EEXIST)
111 break;
112 } while (++cnt);
113
114 return cnt;
115}
116EXPORT_SYMBOL(of_gpio_count);
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129static int of_gpio_simple_xlate(struct gpio_chip *gc, struct device_node *np,
130 const void *gpio_spec, u32 *flags)
131{
132 const __be32 *gpio = gpio_spec;
133 const u32 n = be32_to_cpup(gpio);
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141 if (gc->of_gpio_n_cells < 2) {
142 WARN_ON(1);
143 return -EINVAL;
144 }
145
146 if (n > gc->ngpio)
147 return -EINVAL;
148
149 if (flags)
150 *flags = be32_to_cpu(gpio[1]);
151
152 return n;
153}
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174int of_mm_gpiochip_add(struct device_node *np,
175 struct of_mm_gpio_chip *mm_gc)
176{
177 int ret = -ENOMEM;
178 struct gpio_chip *gc = &mm_gc->gc;
179
180 gc->label = kstrdup(np->full_name, GFP_KERNEL);
181 if (!gc->label)
182 goto err0;
183
184 mm_gc->regs = of_iomap(np, 0);
185 if (!mm_gc->regs)
186 goto err1;
187
188 gc->base = -1;
189
190 if (mm_gc->save_regs)
191 mm_gc->save_regs(mm_gc);
192
193 mm_gc->gc.of_node = np;
194
195 ret = gpiochip_add(gc);
196 if (ret)
197 goto err2;
198
199 pr_debug("%s: registered as generic GPIO chip, base is %d\n",
200 np->full_name, gc->base);
201 return 0;
202err2:
203 iounmap(mm_gc->regs);
204err1:
205 kfree(gc->label);
206err0:
207 pr_err("%s: GPIO chip registration failed with status %d\n",
208 np->full_name, ret);
209 return ret;
210}
211EXPORT_SYMBOL(of_mm_gpiochip_add);
212
213void of_gpiochip_add(struct gpio_chip *chip)
214{
215 if ((!chip->of_node) && (chip->dev))
216 chip->of_node = chip->dev->of_node;
217
218 if (!chip->of_node)
219 return;
220
221 if (!chip->of_xlate) {
222 chip->of_gpio_n_cells = 2;
223 chip->of_xlate = of_gpio_simple_xlate;
224 }
225
226 of_node_get(chip->of_node);
227}
228
229void of_gpiochip_remove(struct gpio_chip *chip)
230{
231 if (chip->of_node)
232 of_node_put(chip->of_node);
233}
234
235
236static int of_gpiochip_is_match(struct gpio_chip *chip, void *data)
237{
238 return chip->of_node == data;
239}
240
241struct gpio_chip *of_node_to_gpiochip(struct device_node *np)
242{
243 return gpiochip_find(np, of_gpiochip_is_match);
244}
245