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 <linux/libfdt.h>
9 #include <linux/err.h>
10 #include <linux/list.h>
11 #include <dm.h>
12 #include <dm/lists.h>
13 #include <dm/pinctrl.h>
14 #include <dm/util.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(dev);
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_stringlist_search(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 	bool pre_reloc_only = !(gd->flags & GD_FLG_RELOC);
125 	const char *name;
126 	ofnode node;
127 	int ret;
128 
129 	dev_for_each_subnode(node, dev) {
130 		if (pre_reloc_only &&
131 		    !ofnode_pre_reloc(node))
132 			continue;
133 		/*
134 		 * If this node has "compatible" property, this is not
135 		 * a pin configuration node, but a normal device. skip.
136 		 */
137 		ofnode_get_property(node, "compatible", &ret);
138 		if (ret >= 0)
139 			continue;
140 
141 		if (ret != -FDT_ERR_NOTFOUND)
142 			return ret;
143 
144 		name = ofnode_get_name(node);
145 		if (!name)
146 			return -EINVAL;
147 		ret = device_bind_driver_to_node(dev, "pinconfig", name,
148 						 node, NULL);
149 		if (ret)
150 			return ret;
151 	}
152 
153 	return 0;
154 }
155 
156 UCLASS_DRIVER(pinconfig) = {
157 	.id = UCLASS_PINCONFIG,
158 	.post_bind = pinconfig_post_bind,
159 	.name = "pinconfig",
160 };
161 
162 U_BOOT_DRIVER(pinconfig_generic) = {
163 	.name = "pinconfig",
164 	.id = UCLASS_PINCONFIG,
165 };
166 
167 #else
168 static int pinctrl_select_state_full(struct udevice *dev, const char *statename)
169 {
170 	return -ENODEV;
171 }
172 
173 static int pinconfig_post_bind(struct udevice *dev)
174 {
175 	return 0;
176 }
177 #endif
178 
179 /**
180  * pinctrl_select_state_simple() - simple implementation of pinctrl_select_state
181  *
182  * @dev: peripheral device
183  * @return: 0 on success, or negative error code on failure
184  */
185 static int pinctrl_select_state_simple(struct udevice *dev)
186 {
187 	struct udevice *pctldev;
188 	struct pinctrl_ops *ops;
189 	int ret;
190 
191 	/*
192 	 * For simplicity, assume the first device of PINCTRL uclass
193 	 * is the correct one.  This is most likely OK as there is
194 	 * usually only one pinctrl device on the system.
195 	 */
196 	ret = uclass_get_device(UCLASS_PINCTRL, 0, &pctldev);
197 	if (ret)
198 		return ret;
199 
200 	ops = pinctrl_get_ops(pctldev);
201 	if (!ops->set_state_simple) {
202 		dev_dbg(dev, "set_state_simple op missing\n");
203 		return -ENOSYS;
204 	}
205 
206 	return ops->set_state_simple(pctldev, dev);
207 }
208 
209 int pinctrl_select_state(struct udevice *dev, const char *statename)
210 {
211 	/*
212 	 * Try full-implemented pinctrl first.
213 	 * If it fails or is not implemented, try simple one.
214 	 */
215 	if (pinctrl_select_state_full(dev, statename))
216 		return pinctrl_select_state_simple(dev);
217 
218 	return 0;
219 }
220 
221 int pinctrl_request(struct udevice *dev, int func, int flags)
222 {
223 	struct pinctrl_ops *ops = pinctrl_get_ops(dev);
224 
225 	if (!ops->request)
226 		return -ENOSYS;
227 
228 	return ops->request(dev, func, flags);
229 }
230 
231 int pinctrl_request_noflags(struct udevice *dev, int func)
232 {
233 	return pinctrl_request(dev, func, 0);
234 }
235 
236 int pinctrl_get_periph_id(struct udevice *dev, struct udevice *periph)
237 {
238 	struct pinctrl_ops *ops = pinctrl_get_ops(dev);
239 
240 	if (!ops->get_periph_id)
241 		return -ENOSYS;
242 
243 	return ops->get_periph_id(dev, periph);
244 }
245 
246 int pinctrl_get_gpio_mux(struct udevice *dev, int banknum, int index)
247 {
248 	struct pinctrl_ops *ops = pinctrl_get_ops(dev);
249 
250 	if (!ops->get_gpio_mux)
251 		return -ENOSYS;
252 
253 	return ops->get_gpio_mux(dev, banknum, index);
254 }
255 
256 /**
257  * pinconfig_post_bind() - post binding for PINCTRL uclass
258  * Recursively bind child nodes as pinconfig devices in case of full pinctrl.
259  *
260  * @dev: pinctrl device
261  * @return: 0 on success, or negative error code on failure
262  */
263 static int pinctrl_post_bind(struct udevice *dev)
264 {
265 	const struct pinctrl_ops *ops = pinctrl_get_ops(dev);
266 
267 	if (!ops) {
268 		dev_dbg(dev, "ops is not set.  Do not bind.\n");
269 		return -EINVAL;
270 	}
271 
272 	/*
273 	 * If set_state callback is set, we assume this pinctrl driver is the
274 	 * full implementation.  In this case, its child nodes should be bound
275 	 * so that peripheral devices can easily search in parent devices
276 	 * during later DT-parsing.
277 	 */
278 	if (ops->set_state)
279 		return pinconfig_post_bind(dev);
280 
281 	return 0;
282 }
283 
284 UCLASS_DRIVER(pinctrl) = {
285 	.id = UCLASS_PINCTRL,
286 	.post_bind = pinctrl_post_bind,
287 	.flags = DM_UC_FLAG_SEQ_ALIAS,
288 	.name = "pinctrl",
289 };
290