1 /*
2  * Copyright (C) 2015  Masahiro Yamada <yamada.masahiro@socionext.com>
3  *
4  * SPDX-License-Identifier:	GPL-2.0+
5  */
6 
7 #include <common.h>
8 #include <libfdt.h>
9 #include <linux/err.h>
10 #include <linux/list.h>
11 #include <dm/device.h>
12 #include <dm/lists.h>
13 #include <dm/pinctrl.h>
14 #include <dm/uclass.h>
15 
16 DECLARE_GLOBAL_DATA_PTR;
17 
18 int pinctrl_decode_pin_config(const void *blob, int node)
19 {
20 	int flags = 0;
21 
22 	if (fdtdec_get_bool(blob, node, "bias-pull-up"))
23 		flags |= 1 << PIN_CONFIG_BIAS_PULL_UP;
24 	else if (fdtdec_get_bool(blob, node, "bias-pull-down"))
25 		flags |= 1 << PIN_CONFIG_BIAS_PULL_DOWN;
26 
27 	return flags;
28 }
29 
30 #if CONFIG_IS_ENABLED(PINCTRL_FULL)
31 /**
32  * pinctrl_config_one() - apply pinctrl settings for a single node
33  *
34  * @config: pin configuration node
35  * @return: 0 on success, or negative error code on failure
36  */
37 static int pinctrl_config_one(struct udevice *config)
38 {
39 	struct udevice *pctldev;
40 	const struct pinctrl_ops *ops;
41 
42 	pctldev = config;
43 	for (;;) {
44 		pctldev = dev_get_parent(pctldev);
45 		if (!pctldev) {
46 			dev_err(config, "could not find pctldev\n");
47 			return -EINVAL;
48 		}
49 		if (pctldev->uclass->uc_drv->id == UCLASS_PINCTRL)
50 			break;
51 	}
52 
53 	ops = pinctrl_get_ops(pctldev);
54 	return ops->set_state(pctldev, config);
55 }
56 
57 /**
58  * pinctrl_select_state_full() - full implementation of pinctrl_select_state
59  *
60  * @dev: peripheral device
61  * @statename: state name, like "default"
62  * @return: 0 on success, or negative error code on failure
63  */
64 static int pinctrl_select_state_full(struct udevice *dev, const char *statename)
65 {
66 	const void *fdt = gd->fdt_blob;
67 	int node = dev->of_offset;
68 	char propname[32]; /* long enough */
69 	const fdt32_t *list;
70 	uint32_t phandle;
71 	int config_node;
72 	struct udevice *config;
73 	int state, size, i, ret;
74 
75 	state = fdt_find_string(fdt, node, "pinctrl-names", statename);
76 	if (state < 0) {
77 		char *end;
78 		/*
79 		 * If statename is not found in "pinctrl-names",
80 		 * assume statename is just the integer state ID.
81 		 */
82 		state = simple_strtoul(statename, &end, 10);
83 		if (*end)
84 			return -EINVAL;
85 	}
86 
87 	snprintf(propname, sizeof(propname), "pinctrl-%d", state);
88 	list = fdt_getprop(fdt, node, propname, &size);
89 	if (!list)
90 		return -EINVAL;
91 
92 	size /= sizeof(*list);
93 	for (i = 0; i < size; i++) {
94 		phandle = fdt32_to_cpu(*list++);
95 
96 		config_node = fdt_node_offset_by_phandle(fdt, phandle);
97 		if (config_node < 0) {
98 			dev_err(dev, "prop %s index %d invalid phandle\n",
99 				propname, i);
100 			return -EINVAL;
101 		}
102 		ret = uclass_get_device_by_of_offset(UCLASS_PINCONFIG,
103 						     config_node, &config);
104 		if (ret)
105 			return ret;
106 
107 		ret = pinctrl_config_one(config);
108 		if (ret)
109 			return ret;
110 	}
111 
112 	return 0;
113 }
114 
115 /**
116  * pinconfig_post-bind() - post binding for PINCONFIG uclass
117  * Recursively bind its children as pinconfig devices.
118  *
119  * @dev: pinconfig device
120  * @return: 0 on success, or negative error code on failure
121  */
122 static int pinconfig_post_bind(struct udevice *dev)
123 {
124 	const void *fdt = gd->fdt_blob;
125 	int offset = dev->of_offset;
126 	bool pre_reloc_only = !(gd->flags & GD_FLG_RELOC);
127 	const char *name;
128 	int ret;
129 
130 	for (offset = fdt_first_subnode(fdt, offset);
131 	     offset > 0;
132 	     offset = fdt_next_subnode(fdt, offset)) {
133 		if (pre_reloc_only &&
134 		    !fdt_getprop(fdt, offset, "u-boot,dm-pre-reloc", NULL))
135 			continue;
136 		/*
137 		 * If this node has "compatible" property, this is not
138 		 * a pin configuration node, but a normal device. skip.
139 		 */
140 		fdt_get_property(fdt, offset, "compatible", &ret);
141 		if (ret >= 0)
142 			continue;
143 
144 		if (ret != -FDT_ERR_NOTFOUND)
145 			return ret;
146 
147 		name = fdt_get_name(fdt, offset, NULL);
148 		if (!name)
149 			return -EINVAL;
150 		ret = device_bind_driver_to_node(dev, "pinconfig", name,
151 						 offset, NULL);
152 		if (ret)
153 			return ret;
154 	}
155 
156 	return 0;
157 }
158 
159 UCLASS_DRIVER(pinconfig) = {
160 	.id = UCLASS_PINCONFIG,
161 	.post_bind = pinconfig_post_bind,
162 	.name = "pinconfig",
163 };
164 
165 U_BOOT_DRIVER(pinconfig_generic) = {
166 	.name = "pinconfig",
167 	.id = UCLASS_PINCONFIG,
168 };
169 
170 #else
171 static int pinctrl_select_state_full(struct udevice *dev, const char *statename)
172 {
173 	return -ENODEV;
174 }
175 
176 static int pinconfig_post_bind(struct udevice *dev)
177 {
178 	return 0;
179 }
180 #endif
181 
182 /**
183  * pinctrl_select_state_simple() - simple implementation of pinctrl_select_state
184  *
185  * @dev: peripheral device
186  * @return: 0 on success, or negative error code on failure
187  */
188 static int pinctrl_select_state_simple(struct udevice *dev)
189 {
190 	struct udevice *pctldev;
191 	struct pinctrl_ops *ops;
192 	int ret;
193 
194 	/*
195 	 * For simplicity, assume the first device of PINCTRL uclass
196 	 * is the correct one.  This is most likely OK as there is
197 	 * usually only one pinctrl device on the system.
198 	 */
199 	ret = uclass_get_device(UCLASS_PINCTRL, 0, &pctldev);
200 	if (ret)
201 		return ret;
202 
203 	ops = pinctrl_get_ops(pctldev);
204 	if (!ops->set_state_simple) {
205 		dev_dbg(dev, "set_state_simple op missing\n");
206 		return -ENOSYS;
207 	}
208 
209 	return ops->set_state_simple(pctldev, dev);
210 }
211 
212 int pinctrl_select_state(struct udevice *dev, const char *statename)
213 {
214 	/*
215 	 * Try full-implemented pinctrl first.
216 	 * If it fails or is not implemented, try simple one.
217 	 */
218 	if (pinctrl_select_state_full(dev, statename))
219 		return pinctrl_select_state_simple(dev);
220 
221 	return 0;
222 }
223 
224 int pinctrl_request(struct udevice *dev, int func, int flags)
225 {
226 	struct pinctrl_ops *ops = pinctrl_get_ops(dev);
227 
228 	if (!ops->request)
229 		return -ENOSYS;
230 
231 	return ops->request(dev, func, flags);
232 }
233 
234 int pinctrl_request_noflags(struct udevice *dev, int func)
235 {
236 	return pinctrl_request(dev, func, 0);
237 }
238 
239 int pinctrl_get_periph_id(struct udevice *dev, struct udevice *periph)
240 {
241 	struct pinctrl_ops *ops = pinctrl_get_ops(dev);
242 
243 	if (!ops->get_periph_id)
244 		return -ENOSYS;
245 
246 	return ops->get_periph_id(dev, periph);
247 }
248 
249 int pinctrl_get_gpio_mux(struct udevice *dev, int banknum, int index)
250 {
251 	struct pinctrl_ops *ops = pinctrl_get_ops(dev);
252 
253 	if (!ops->get_gpio_mux)
254 		return -ENOSYS;
255 
256 	return ops->get_gpio_mux(dev, banknum, index);
257 }
258 
259 /**
260  * pinconfig_post-bind() - post binding for PINCTRL uclass
261  * Recursively bind child nodes as pinconfig devices in case of full pinctrl.
262  *
263  * @dev: pinctrl device
264  * @return: 0 on success, or negative error code on failure
265  */
266 static int pinctrl_post_bind(struct udevice *dev)
267 {
268 	const struct pinctrl_ops *ops = pinctrl_get_ops(dev);
269 
270 	if (!ops) {
271 		dev_dbg(dev, "ops is not set.  Do not bind.\n");
272 		return -EINVAL;
273 	}
274 
275 	/*
276 	 * If set_state callback is set, we assume this pinctrl driver is the
277 	 * full implementation.  In this case, its child nodes should be bound
278 	 * so that peripheral devices can easily search in parent devices
279 	 * during later DT-parsing.
280 	 */
281 	if (ops->set_state)
282 		return pinconfig_post_bind(dev);
283 
284 	return 0;
285 }
286 
287 UCLASS_DRIVER(pinctrl) = {
288 	.id = UCLASS_PINCTRL,
289 	.post_bind = pinctrl_post_bind,
290 	.name = "pinctrl",
291 };
292