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 #include <dm/util.h>
16 
17 DECLARE_GLOBAL_DATA_PTR;
18 
19 int pinctrl_decode_pin_config(const void *blob, int node)
20 {
21 	int flags = 0;
22 
23 	if (fdtdec_get_bool(blob, node, "bias-pull-up"))
24 		flags |= 1 << PIN_CONFIG_BIAS_PULL_UP;
25 	else if (fdtdec_get_bool(blob, node, "bias-pull-down"))
26 		flags |= 1 << PIN_CONFIG_BIAS_PULL_DOWN;
27 
28 	return flags;
29 }
30 
31 #if CONFIG_IS_ENABLED(PINCTRL_FULL)
32 /**
33  * pinctrl_config_one() - apply pinctrl settings for a single node
34  *
35  * @config: pin configuration node
36  * @return: 0 on success, or negative error code on failure
37  */
38 static int pinctrl_config_one(struct udevice *config)
39 {
40 	struct udevice *pctldev;
41 	const struct pinctrl_ops *ops;
42 
43 	pctldev = config;
44 	for (;;) {
45 		pctldev = dev_get_parent(pctldev);
46 		if (!pctldev) {
47 			dev_err(config, "could not find pctldev\n");
48 			return -EINVAL;
49 		}
50 		if (pctldev->uclass->uc_drv->id == UCLASS_PINCTRL)
51 			break;
52 	}
53 
54 	ops = pinctrl_get_ops(pctldev);
55 	return ops->set_state(pctldev, config);
56 }
57 
58 /**
59  * pinctrl_select_state_full() - full implementation of pinctrl_select_state
60  *
61  * @dev: peripheral device
62  * @statename: state name, like "default"
63  * @return: 0 on success, or negative error code on failure
64  */
65 static int pinctrl_select_state_full(struct udevice *dev, const char *statename)
66 {
67 	const void *fdt = gd->fdt_blob;
68 	int node = dev_of_offset(dev);
69 	char propname[32]; /* long enough */
70 	const fdt32_t *list;
71 	uint32_t phandle;
72 	int config_node;
73 	struct udevice *config;
74 	int state, size, i, ret;
75 
76 	state = fdt_stringlist_search(fdt, node, "pinctrl-names", statename);
77 	if (state < 0) {
78 		char *end;
79 		/*
80 		 * If statename is not found in "pinctrl-names",
81 		 * assume statename is just the integer state ID.
82 		 */
83 		state = simple_strtoul(statename, &end, 10);
84 		if (*end)
85 			return -EINVAL;
86 	}
87 
88 	snprintf(propname, sizeof(propname), "pinctrl-%d", state);
89 	list = fdt_getprop(fdt, node, propname, &size);
90 	if (!list)
91 		return -EINVAL;
92 
93 	size /= sizeof(*list);
94 	for (i = 0; i < size; i++) {
95 		phandle = fdt32_to_cpu(*list++);
96 
97 		config_node = fdt_node_offset_by_phandle(fdt, phandle);
98 		if (config_node < 0) {
99 			dev_err(dev, "prop %s index %d invalid phandle\n",
100 				propname, i);
101 			return -EINVAL;
102 		}
103 		ret = uclass_get_device_by_of_offset(UCLASS_PINCONFIG,
104 						     config_node, &config);
105 		if (ret)
106 			return ret;
107 
108 		ret = pinctrl_config_one(config);
109 		if (ret)
110 			return ret;
111 	}
112 
113 	return 0;
114 }
115 
116 /**
117  * pinconfig_post_bind() - post binding for PINCONFIG uclass
118  * Recursively bind its children as pinconfig devices.
119  *
120  * @dev: pinconfig device
121  * @return: 0 on success, or negative error code on failure
122  */
123 static int pinconfig_post_bind(struct udevice *dev)
124 {
125 	const void *fdt = gd->fdt_blob;
126 	int offset = dev_of_offset(dev);
127 	bool pre_reloc_only = !(gd->flags & GD_FLG_RELOC);
128 	const char *name;
129 	int ret;
130 
131 	for (offset = fdt_first_subnode(fdt, offset);
132 	     offset > 0;
133 	     offset = fdt_next_subnode(fdt, offset)) {
134 		if (pre_reloc_only &&
135 		    !dm_fdt_pre_reloc(fdt, offset))
136 			continue;
137 		/*
138 		 * If this node has "compatible" property, this is not
139 		 * a pin configuration node, but a normal device. skip.
140 		 */
141 		fdt_get_property(fdt, offset, "compatible", &ret);
142 		if (ret >= 0)
143 			continue;
144 
145 		if (ret != -FDT_ERR_NOTFOUND)
146 			return ret;
147 
148 		name = fdt_get_name(fdt, offset, NULL);
149 		if (!name)
150 			return -EINVAL;
151 		ret = device_bind_driver_to_node(dev, "pinconfig", name,
152 						 offset, NULL);
153 		if (ret)
154 			return ret;
155 	}
156 
157 	return 0;
158 }
159 
160 UCLASS_DRIVER(pinconfig) = {
161 	.id = UCLASS_PINCONFIG,
162 	.post_bind = pinconfig_post_bind,
163 	.name = "pinconfig",
164 };
165 
166 U_BOOT_DRIVER(pinconfig_generic) = {
167 	.name = "pinconfig",
168 	.id = UCLASS_PINCONFIG,
169 };
170 
171 #else
172 static int pinctrl_select_state_full(struct udevice *dev, const char *statename)
173 {
174 	return -ENODEV;
175 }
176 
177 static int pinconfig_post_bind(struct udevice *dev)
178 {
179 	return 0;
180 }
181 #endif
182 
183 /**
184  * pinctrl_select_state_simple() - simple implementation of pinctrl_select_state
185  *
186  * @dev: peripheral device
187  * @return: 0 on success, or negative error code on failure
188  */
189 static int pinctrl_select_state_simple(struct udevice *dev)
190 {
191 	struct udevice *pctldev;
192 	struct pinctrl_ops *ops;
193 	int ret;
194 
195 	/*
196 	 * For simplicity, assume the first device of PINCTRL uclass
197 	 * is the correct one.  This is most likely OK as there is
198 	 * usually only one pinctrl device on the system.
199 	 */
200 	ret = uclass_get_device(UCLASS_PINCTRL, 0, &pctldev);
201 	if (ret)
202 		return ret;
203 
204 	ops = pinctrl_get_ops(pctldev);
205 	if (!ops->set_state_simple) {
206 		dev_dbg(dev, "set_state_simple op missing\n");
207 		return -ENOSYS;
208 	}
209 
210 	return ops->set_state_simple(pctldev, dev);
211 }
212 
213 int pinctrl_select_state(struct udevice *dev, const char *statename)
214 {
215 	/*
216 	 * Try full-implemented pinctrl first.
217 	 * If it fails or is not implemented, try simple one.
218 	 */
219 	if (pinctrl_select_state_full(dev, statename))
220 		return pinctrl_select_state_simple(dev);
221 
222 	return 0;
223 }
224 
225 int pinctrl_request(struct udevice *dev, int func, int flags)
226 {
227 	struct pinctrl_ops *ops = pinctrl_get_ops(dev);
228 
229 	if (!ops->request)
230 		return -ENOSYS;
231 
232 	return ops->request(dev, func, flags);
233 }
234 
235 int pinctrl_request_noflags(struct udevice *dev, int func)
236 {
237 	return pinctrl_request(dev, func, 0);
238 }
239 
240 int pinctrl_get_periph_id(struct udevice *dev, struct udevice *periph)
241 {
242 	struct pinctrl_ops *ops = pinctrl_get_ops(dev);
243 
244 	if (!ops->get_periph_id)
245 		return -ENOSYS;
246 
247 	return ops->get_periph_id(dev, periph);
248 }
249 
250 int pinctrl_get_gpio_mux(struct udevice *dev, int banknum, int index)
251 {
252 	struct pinctrl_ops *ops = pinctrl_get_ops(dev);
253 
254 	if (!ops->get_gpio_mux)
255 		return -ENOSYS;
256 
257 	return ops->get_gpio_mux(dev, banknum, index);
258 }
259 
260 /**
261  * pinconfig_post_bind() - post binding for PINCTRL uclass
262  * Recursively bind child nodes as pinconfig devices in case of full pinctrl.
263  *
264  * @dev: pinctrl device
265  * @return: 0 on success, or negative error code on failure
266  */
267 static int pinctrl_post_bind(struct udevice *dev)
268 {
269 	const struct pinctrl_ops *ops = pinctrl_get_ops(dev);
270 
271 	if (!ops) {
272 		dev_dbg(dev, "ops is not set.  Do not bind.\n");
273 		return -EINVAL;
274 	}
275 
276 	/*
277 	 * If set_state callback is set, we assume this pinctrl driver is the
278 	 * full implementation.  In this case, its child nodes should be bound
279 	 * so that peripheral devices can easily search in parent devices
280 	 * during later DT-parsing.
281 	 */
282 	if (ops->set_state)
283 		return pinconfig_post_bind(dev);
284 
285 	return 0;
286 }
287 
288 UCLASS_DRIVER(pinctrl) = {
289 	.id = UCLASS_PINCTRL,
290 	.post_bind = pinctrl_post_bind,
291 	.flags = DM_UC_FLAG_SEQ_ALIAS,
292 	.name = "pinctrl",
293 };
294