Commit | Line | Data |
---|---|---|
863fbf49 AV |
1 | /* |
2 | * OF helpers for the GPIO API | |
3 | * | |
4 | * Copyright (c) 2007-2008 MontaVista Software, Inc. | |
5 | * | |
6 | * Author: Anton Vorontsov <avorontsov@ru.mvista.com> | |
7 | * | |
8 | * This program is free software; you can redistribute it and/or modify | |
9 | * it under the terms of the GNU General Public License as published by | |
10 | * the Free Software Foundation; either version 2 of the License, or | |
11 | * (at your option) any later version. | |
12 | */ | |
13 | ||
2e13cba8 | 14 | #include <linux/device.h> |
863fbf49 | 15 | #include <linux/errno.h> |
2e13cba8 | 16 | #include <linux/module.h> |
863fbf49 | 17 | #include <linux/io.h> |
af8b6375 | 18 | #include <linux/gpio/consumer.h> |
863fbf49 | 19 | #include <linux/of.h> |
2e13cba8 | 20 | #include <linux/of_address.h> |
863fbf49 | 21 | #include <linux/of_gpio.h> |
f23f1516 | 22 | #include <linux/pinctrl/pinctrl.h> |
2e13cba8 | 23 | #include <linux/slab.h> |
863fbf49 | 24 | |
af8b6375 AC |
25 | struct gpio_desc; |
26 | ||
0df2c999 | 27 | /* Private data structure for of_gpiochip_find_and_xlate */ |
3d0f7cf0 GL |
28 | struct gg_data { |
29 | enum of_gpio_flags *flags; | |
30 | struct of_phandle_args gpiospec; | |
31 | ||
af8b6375 | 32 | struct gpio_desc *out_gpio; |
3d0f7cf0 GL |
33 | }; |
34 | ||
35 | /* Private function for resolving node pointer to gpio_chip */ | |
36 | static int of_gpiochip_find_and_xlate(struct gpio_chip *gc, void *data) | |
37 | { | |
38 | struct gg_data *gg_data = data; | |
39 | int ret; | |
40 | ||
41 | if ((gc->of_node != gg_data->gpiospec.np) || | |
42 | (gc->of_gpio_n_cells != gg_data->gpiospec.args_count) || | |
43 | (!gc->of_xlate)) | |
44 | return false; | |
45 | ||
46 | ret = gc->of_xlate(gc, &gg_data->gpiospec, gg_data->flags); | |
47 | if (ret < 0) | |
48 | return false; | |
49 | ||
af8b6375 | 50 | gg_data->out_gpio = gpio_to_desc(ret + gc->base); |
3d0f7cf0 GL |
51 | return true; |
52 | } | |
53 | ||
863fbf49 | 54 | /** |
af8b6375 | 55 | * of_get_named_gpiod_flags() - Get a GPIO descriptor and flags for GPIO API |
863fbf49 | 56 | * @np: device node to get GPIO from |
a6b09191 | 57 | * @propname: property name containing gpio specifier(s) |
863fbf49 | 58 | * @index: index of the GPIO |
b908b53d | 59 | * @flags: a flags pointer to fill in |
863fbf49 | 60 | * |
af8b6375 | 61 | * Returns GPIO descriptor to use with Linux GPIO API, or one of the errno |
b908b53d AV |
62 | * value on the error condition. If @flags is not NULL the function also fills |
63 | * in flags for the GPIO. | |
863fbf49 | 64 | */ |
af8b6375 AC |
65 | struct gpio_desc *of_get_named_gpiod_flags(struct device_node *np, |
66 | const char *propname, int index, enum of_gpio_flags *flags) | |
863fbf49 | 67 | { |
4fbb0022 RS |
68 | /* Return -EPROBE_DEFER to support probe() functions to be called |
69 | * later when the GPIO actually becomes available | |
70 | */ | |
af8b6375 AC |
71 | struct gg_data gg_data = { |
72 | .flags = flags, | |
73 | .out_gpio = ERR_PTR(-EPROBE_DEFER) | |
74 | }; | |
64b60e09 | 75 | int ret; |
3d0f7cf0 GL |
76 | |
77 | /* .of_xlate might decide to not fill in the flags, so clear it. */ | |
78 | if (flags) | |
79 | *flags = 0; | |
863fbf49 | 80 | |
15c9a0ac | 81 | ret = of_parse_phandle_with_args(np, propname, "#gpio-cells", index, |
3d0f7cf0 | 82 | &gg_data.gpiospec); |
64b60e09 | 83 | if (ret) { |
eddf8176 LW |
84 | pr_debug("%s: can't parse gpios property of node '%s[%d]'\n", |
85 | __func__, np->full_name, index); | |
af8b6375 | 86 | return ERR_PTR(ret); |
863fbf49 AV |
87 | } |
88 | ||
3d0f7cf0 | 89 | gpiochip_find(&gg_data, of_gpiochip_find_and_xlate); |
863fbf49 | 90 | |
3d0f7cf0 | 91 | of_node_put(gg_data.gpiospec.np); |
af8b6375 AC |
92 | pr_debug("%s exited with status %d\n", __func__, |
93 | PTR_RET(gg_data.out_gpio)); | |
3d0f7cf0 | 94 | return gg_data.out_gpio; |
863fbf49 | 95 | } |
af8b6375 | 96 | EXPORT_SYMBOL(of_get_named_gpiod_flags); |
863fbf49 AV |
97 | |
98 | /** | |
b908b53d | 99 | * of_gpio_simple_xlate - translate gpio_spec to the GPIO number and flags |
a19e3da5 | 100 | * @gc: pointer to the gpio_chip structure |
863fbf49 AV |
101 | * @np: device node of the GPIO chip |
102 | * @gpio_spec: gpio specifier as found in the device tree | |
b908b53d | 103 | * @flags: a flags pointer to fill in |
863fbf49 AV |
104 | * |
105 | * This is simple translation function, suitable for the most 1:1 mapped | |
106 | * gpio chips. This function performs only one sanity check: whether gpio | |
107 | * is less than ngpios (that is specified in the gpio_chip). | |
108 | */ | |
15c9a0ac GL |
109 | int of_gpio_simple_xlate(struct gpio_chip *gc, |
110 | const struct of_phandle_args *gpiospec, u32 *flags) | |
863fbf49 | 111 | { |
b908b53d AV |
112 | /* |
113 | * We're discouraging gpio_cells < 2, since that way you'll have to | |
114 | * write your own xlate function (that will have to retrive the GPIO | |
115 | * number and the flags from a single gpio cell -- this is possible, | |
116 | * but not recommended). | |
117 | */ | |
a19e3da5 | 118 | if (gc->of_gpio_n_cells < 2) { |
b908b53d AV |
119 | WARN_ON(1); |
120 | return -EINVAL; | |
121 | } | |
122 | ||
15c9a0ac GL |
123 | if (WARN_ON(gpiospec->args_count < gc->of_gpio_n_cells)) |
124 | return -EINVAL; | |
125 | ||
6270d830 | 126 | if (gpiospec->args[0] >= gc->ngpio) |
863fbf49 AV |
127 | return -EINVAL; |
128 | ||
b908b53d | 129 | if (flags) |
15c9a0ac | 130 | *flags = gpiospec->args[1]; |
b908b53d | 131 | |
15c9a0ac | 132 | return gpiospec->args[0]; |
863fbf49 | 133 | } |
3038bbdf | 134 | EXPORT_SYMBOL(of_gpio_simple_xlate); |
863fbf49 | 135 | |
863fbf49 AV |
136 | /** |
137 | * of_mm_gpiochip_add - Add memory mapped GPIO chip (bank) | |
138 | * @np: device node of the GPIO chip | |
139 | * @mm_gc: pointer to the of_mm_gpio_chip allocated structure | |
140 | * | |
141 | * To use this function you should allocate and fill mm_gc with: | |
142 | * | |
143 | * 1) In the gpio_chip structure: | |
144 | * - all the callbacks | |
a19e3da5 AV |
145 | * - of_gpio_n_cells |
146 | * - of_xlate callback (optional) | |
863fbf49 AV |
147 | * |
148 | * 3) In the of_mm_gpio_chip structure: | |
149 | * - save_regs callback (optional) | |
150 | * | |
151 | * If succeeded, this function will map bank's memory and will | |
152 | * do all necessary work for you. Then you'll able to use .regs | |
153 | * to manage GPIOs from the callbacks. | |
154 | */ | |
155 | int of_mm_gpiochip_add(struct device_node *np, | |
156 | struct of_mm_gpio_chip *mm_gc) | |
157 | { | |
158 | int ret = -ENOMEM; | |
a19e3da5 | 159 | struct gpio_chip *gc = &mm_gc->gc; |
863fbf49 AV |
160 | |
161 | gc->label = kstrdup(np->full_name, GFP_KERNEL); | |
162 | if (!gc->label) | |
163 | goto err0; | |
164 | ||
165 | mm_gc->regs = of_iomap(np, 0); | |
166 | if (!mm_gc->regs) | |
167 | goto err1; | |
168 | ||
21451155 | 169 | gc->base = -1; |
863fbf49 | 170 | |
863fbf49 AV |
171 | if (mm_gc->save_regs) |
172 | mm_gc->save_regs(mm_gc); | |
173 | ||
a19e3da5 | 174 | mm_gc->gc.of_node = np; |
863fbf49 AV |
175 | |
176 | ret = gpiochip_add(gc); | |
177 | if (ret) | |
178 | goto err2; | |
179 | ||
863fbf49 AV |
180 | return 0; |
181 | err2: | |
863fbf49 AV |
182 | iounmap(mm_gc->regs); |
183 | err1: | |
184 | kfree(gc->label); | |
185 | err0: | |
186 | pr_err("%s: GPIO chip registration failed with status %d\n", | |
187 | np->full_name, ret); | |
188 | return ret; | |
189 | } | |
190 | EXPORT_SYMBOL(of_mm_gpiochip_add); | |
594fa265 | 191 | |
f23f1516 | 192 | #ifdef CONFIG_PINCTRL |
167c1af9 | 193 | static void of_gpiochip_add_pin_range(struct gpio_chip *chip) |
f23f1516 SH |
194 | { |
195 | struct device_node *np = chip->of_node; | |
f23f1516 | 196 | struct of_phandle_args pinspec; |
1e63d7b9 | 197 | struct pinctrl_dev *pctldev; |
f23f1516 SH |
198 | int index = 0, ret; |
199 | ||
200 | if (!np) | |
201 | return; | |
202 | ||
ad4e1a7c | 203 | for (;; index++) { |
d9fe0039 SW |
204 | ret = of_parse_phandle_with_fixed_args(np, "gpio-ranges", 3, |
205 | index, &pinspec); | |
f23f1516 SH |
206 | if (ret) |
207 | break; | |
208 | ||
1e63d7b9 LW |
209 | pctldev = of_pinctrl_get(pinspec.np); |
210 | if (!pctldev) | |
f23f1516 | 211 | break; |
f23f1516 | 212 | |
1e63d7b9 | 213 | ret = gpiochip_add_pin_range(chip, |
ef5e3eef | 214 | pinctrl_dev_get_devname(pctldev), |
1e63d7b9 | 215 | pinspec.args[0], |
86853c83 HZ |
216 | pinspec.args[1], |
217 | pinspec.args[2]); | |
f23f1516 | 218 | |
1e63d7b9 LW |
219 | if (ret) |
220 | break; | |
ad4e1a7c | 221 | } |
f23f1516 SH |
222 | } |
223 | ||
f23f1516 | 224 | #else |
167c1af9 | 225 | static void of_gpiochip_add_pin_range(struct gpio_chip *chip) {} |
f23f1516 SH |
226 | #endif |
227 | ||
391c970c AV |
228 | void of_gpiochip_add(struct gpio_chip *chip) |
229 | { | |
230 | if ((!chip->of_node) && (chip->dev)) | |
231 | chip->of_node = chip->dev->of_node; | |
232 | ||
233 | if (!chip->of_node) | |
234 | return; | |
235 | ||
236 | if (!chip->of_xlate) { | |
237 | chip->of_gpio_n_cells = 2; | |
238 | chip->of_xlate = of_gpio_simple_xlate; | |
239 | } | |
240 | ||
f23f1516 | 241 | of_gpiochip_add_pin_range(chip); |
391c970c AV |
242 | of_node_get(chip->of_node); |
243 | } | |
244 | ||
245 | void of_gpiochip_remove(struct gpio_chip *chip) | |
246 | { | |
e93fa3f2 | 247 | gpiochip_remove_pin_ranges(chip); |
f23f1516 | 248 | |
391c970c AV |
249 | if (chip->of_node) |
250 | of_node_put(chip->of_node); | |
251 | } |