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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/gpio.h>
19#include <linux/of.h>
20#include <linux/of_address.h>
21#include <linux/of_gpio.h>
22#include <linux/pinctrl/pinctrl.h>
23#include <linux/slab.h>
24
25
26struct gg_data {
27 enum of_gpio_flags *flags;
28 struct of_phandle_args gpiospec;
29
30 int out_gpio;
31};
32
33
34static int of_gpiochip_find_and_xlate(struct gpio_chip *gc, void *data)
35{
36 struct gg_data *gg_data = data;
37 int ret;
38
39 if ((gc->of_node != gg_data->gpiospec.np) ||
40 (gc->of_gpio_n_cells != gg_data->gpiospec.args_count) ||
41 (!gc->of_xlate))
42 return false;
43
44 ret = gc->of_xlate(gc, &gg_data->gpiospec, gg_data->flags);
45 if (ret < 0)
46 return false;
47
48 gg_data->out_gpio = ret + gc->base;
49 return true;
50}
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63int of_get_named_gpio_flags(struct device_node *np, const char *propname,
64 int index, enum of_gpio_flags *flags)
65{
66
67
68
69 struct gg_data gg_data = { .flags = flags, .out_gpio = -EPROBE_DEFER };
70 int ret;
71
72
73 if (flags)
74 *flags = 0;
75
76 ret = of_parse_phandle_with_args(np, propname, "#gpio-cells", index,
77 &gg_data.gpiospec);
78 if (ret) {
79 pr_debug("%s: can't parse gpios property\n", __func__);
80 return ret;
81 }
82
83 gpiochip_find(&gg_data, of_gpiochip_find_and_xlate);
84
85 of_node_put(gg_data.gpiospec.np);
86 pr_debug("%s exited with status %d\n", __func__, gg_data.out_gpio);
87 return gg_data.out_gpio;
88}
89EXPORT_SYMBOL(of_get_named_gpio_flags);
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101
102int of_gpio_simple_xlate(struct gpio_chip *gc,
103 const struct of_phandle_args *gpiospec, u32 *flags)
104{
105
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110
111 if (gc->of_gpio_n_cells < 2) {
112 WARN_ON(1);
113 return -EINVAL;
114 }
115
116 if (WARN_ON(gpiospec->args_count < gc->of_gpio_n_cells))
117 return -EINVAL;
118
119 if (gpiospec->args[0] >= gc->ngpio)
120 return -EINVAL;
121
122 if (flags)
123 *flags = gpiospec->args[1];
124
125 return gpiospec->args[0];
126}
127EXPORT_SYMBOL(of_gpio_simple_xlate);
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148int of_mm_gpiochip_add(struct device_node *np,
149 struct of_mm_gpio_chip *mm_gc)
150{
151 int ret = -ENOMEM;
152 struct gpio_chip *gc = &mm_gc->gc;
153
154 gc->label = kstrdup(np->full_name, GFP_KERNEL);
155 if (!gc->label)
156 goto err0;
157
158 mm_gc->regs = of_iomap(np, 0);
159 if (!mm_gc->regs)
160 goto err1;
161
162 gc->base = -1;
163
164 if (mm_gc->save_regs)
165 mm_gc->save_regs(mm_gc);
166
167 mm_gc->gc.of_node = np;
168
169 ret = gpiochip_add(gc);
170 if (ret)
171 goto err2;
172
173 return 0;
174err2:
175 iounmap(mm_gc->regs);
176err1:
177 kfree(gc->label);
178err0:
179 pr_err("%s: GPIO chip registration failed with status %d\n",
180 np->full_name, ret);
181 return ret;
182}
183EXPORT_SYMBOL(of_mm_gpiochip_add);
184
185#ifdef CONFIG_PINCTRL
186static void of_gpiochip_add_pin_range(struct gpio_chip *chip)
187{
188 struct device_node *np = chip->of_node;
189 struct of_phandle_args pinspec;
190 struct pinctrl_dev *pctldev;
191 int index = 0, ret;
192
193 if (!np)
194 return;
195
196 for (;; index++) {
197 ret = of_parse_phandle_with_args(np, "gpio-ranges",
198 "#gpio-range-cells", index, &pinspec);
199 if (ret)
200 break;
201
202 pctldev = of_pinctrl_get(pinspec.np);
203 if (!pctldev)
204 break;
205
206 ret = gpiochip_add_pin_range(chip,
207 pinctrl_dev_get_devname(pctldev),
208 pinspec.args[0],
209 pinspec.args[1],
210 pinspec.args[2]);
211
212 if (ret)
213 break;
214 }
215}
216
217#else
218static void of_gpiochip_add_pin_range(struct gpio_chip *chip) {}
219#endif
220
221void of_gpiochip_add(struct gpio_chip *chip)
222{
223 if ((!chip->of_node) && (chip->dev))
224 chip->of_node = chip->dev->of_node;
225
226 if (!chip->of_node)
227 return;
228
229 if (!chip->of_xlate) {
230 chip->of_gpio_n_cells = 2;
231 chip->of_xlate = of_gpio_simple_xlate;
232 }
233
234 of_gpiochip_add_pin_range(chip);
235 of_node_get(chip->of_node);
236}
237
238void of_gpiochip_remove(struct gpio_chip *chip)
239{
240 gpiochip_remove_pin_ranges(chip);
241
242 if (chip->of_node)
243 of_node_put(chip->of_node);
244}
245