1 /*
2  *  linux/drivers/pinctrl/pinctrl-lantiq.c
3  *  based on linux/drivers/pinctrl/pinctrl-pxa3xx.c
4  *
5  *  This program is free software; you can redistribute it and/or modify
6  *  it under the terms of the GNU General Public License version 2 as
7  *  publishhed by the Free Software Foundation.
8  *
9  *  Copyright (C) 2012 John Crispin <john@phrozen.org>
10  */
11 
12 #include <linux/module.h>
13 #include <linux/device.h>
14 #include <linux/io.h>
15 #include <linux/platform_device.h>
16 #include <linux/slab.h>
17 #include <linux/of.h>
18 
19 #include "pinctrl-lantiq.h"
20 
21 static int ltq_get_group_count(struct pinctrl_dev *pctrldev)
22 {
23 	struct ltq_pinmux_info *info = pinctrl_dev_get_drvdata(pctrldev);
24 	return info->num_grps;
25 }
26 
27 static const char *ltq_get_group_name(struct pinctrl_dev *pctrldev,
28 					 unsigned selector)
29 {
30 	struct ltq_pinmux_info *info = pinctrl_dev_get_drvdata(pctrldev);
31 	if (selector >= info->num_grps)
32 		return NULL;
33 	return info->grps[selector].name;
34 }
35 
36 static int ltq_get_group_pins(struct pinctrl_dev *pctrldev,
37 				 unsigned selector,
38 				 const unsigned **pins,
39 				 unsigned *num_pins)
40 {
41 	struct ltq_pinmux_info *info = pinctrl_dev_get_drvdata(pctrldev);
42 	if (selector >= info->num_grps)
43 		return -EINVAL;
44 	*pins = info->grps[selector].pins;
45 	*num_pins = info->grps[selector].npins;
46 	return 0;
47 }
48 
49 static void ltq_pinctrl_dt_free_map(struct pinctrl_dev *pctldev,
50 				    struct pinctrl_map *map, unsigned num_maps)
51 {
52 	int i;
53 
54 	for (i = 0; i < num_maps; i++)
55 		if (map[i].type == PIN_MAP_TYPE_CONFIGS_PIN ||
56 		    map[i].type == PIN_MAP_TYPE_CONFIGS_GROUP)
57 			kfree(map[i].data.configs.configs);
58 	kfree(map);
59 }
60 
61 static void ltq_pinctrl_pin_dbg_show(struct pinctrl_dev *pctldev,
62 					struct seq_file *s,
63 					unsigned offset)
64 {
65 	seq_printf(s, " %s", dev_name(pctldev->dev));
66 }
67 
68 static void ltq_pinctrl_dt_subnode_to_map(struct pinctrl_dev *pctldev,
69 				struct device_node *np,
70 				struct pinctrl_map **map)
71 {
72 	struct ltq_pinmux_info *info = pinctrl_dev_get_drvdata(pctldev);
73 	struct property *pins = of_find_property(np, "lantiq,pins", NULL);
74 	struct property *groups = of_find_property(np, "lantiq,groups", NULL);
75 	unsigned long configs[3];
76 	unsigned num_configs = 0;
77 	struct property *prop;
78 	const char *group, *pin;
79 	const char *function;
80 	int ret, i;
81 
82 	if (!pins && !groups) {
83 		dev_err(pctldev->dev, "%s defines neither pins nor groups\n",
84 			np->name);
85 		return;
86 	}
87 
88 	if (pins && groups) {
89 		dev_err(pctldev->dev, "%s defines both pins and groups\n",
90 			np->name);
91 		return;
92 	}
93 
94 	ret = of_property_read_string(np, "lantiq,function", &function);
95 	if (groups && !ret) {
96 		of_property_for_each_string(np, "lantiq,groups", prop, group) {
97 			(*map)->type = PIN_MAP_TYPE_MUX_GROUP;
98 			(*map)->name = function;
99 			(*map)->data.mux.group = group;
100 			(*map)->data.mux.function = function;
101 			(*map)++;
102 		}
103 	}
104 
105 	for (i = 0; i < info->num_params; i++) {
106 		u32 val;
107 		int ret = of_property_read_u32(np,
108 				info->params[i].property, &val);
109 		if (!ret)
110 			configs[num_configs++] =
111 				LTQ_PINCONF_PACK(info->params[i].param,
112 				val);
113 	}
114 
115 	if (!num_configs)
116 		return;
117 
118 	of_property_for_each_string(np, "lantiq,pins", prop, pin) {
119 		(*map)->data.configs.configs = kmemdup(configs,
120 					num_configs * sizeof(unsigned long),
121 					GFP_KERNEL);
122 		(*map)->type = PIN_MAP_TYPE_CONFIGS_PIN;
123 		(*map)->name = pin;
124 		(*map)->data.configs.group_or_pin = pin;
125 		(*map)->data.configs.num_configs = num_configs;
126 		(*map)++;
127 	}
128 	of_property_for_each_string(np, "lantiq,groups", prop, group) {
129 		(*map)->data.configs.configs = kmemdup(configs,
130 					num_configs * sizeof(unsigned long),
131 					GFP_KERNEL);
132 		(*map)->type = PIN_MAP_TYPE_CONFIGS_GROUP;
133 		(*map)->name = group;
134 		(*map)->data.configs.group_or_pin = group;
135 		(*map)->data.configs.num_configs = num_configs;
136 		(*map)++;
137 	}
138 }
139 
140 static int ltq_pinctrl_dt_subnode_size(struct device_node *np)
141 {
142 	int ret;
143 
144 	ret = of_property_count_strings(np, "lantiq,groups");
145 	if (ret < 0)
146 		ret = of_property_count_strings(np, "lantiq,pins");
147 	return ret;
148 }
149 
150 static int ltq_pinctrl_dt_node_to_map(struct pinctrl_dev *pctldev,
151 				      struct device_node *np_config,
152 				      struct pinctrl_map **map,
153 				      unsigned *num_maps)
154 {
155 	struct pinctrl_map *tmp;
156 	struct device_node *np;
157 	int max_maps = 0;
158 
159 	for_each_child_of_node(np_config, np)
160 		max_maps += ltq_pinctrl_dt_subnode_size(np);
161 	*map = kzalloc(max_maps * sizeof(struct pinctrl_map) * 2, GFP_KERNEL);
162 	if (!*map)
163 		return -ENOMEM;
164 	tmp = *map;
165 
166 	for_each_child_of_node(np_config, np)
167 		ltq_pinctrl_dt_subnode_to_map(pctldev, np, &tmp);
168 	*num_maps = ((int)(tmp - *map));
169 
170 	return 0;
171 }
172 
173 static const struct pinctrl_ops ltq_pctrl_ops = {
174 	.get_groups_count	= ltq_get_group_count,
175 	.get_group_name		= ltq_get_group_name,
176 	.get_group_pins		= ltq_get_group_pins,
177 	.pin_dbg_show		= ltq_pinctrl_pin_dbg_show,
178 	.dt_node_to_map		= ltq_pinctrl_dt_node_to_map,
179 	.dt_free_map		= ltq_pinctrl_dt_free_map,
180 };
181 
182 static int ltq_pmx_func_count(struct pinctrl_dev *pctrldev)
183 {
184 	struct ltq_pinmux_info *info = pinctrl_dev_get_drvdata(pctrldev);
185 
186 	return info->num_funcs;
187 }
188 
189 static const char *ltq_pmx_func_name(struct pinctrl_dev *pctrldev,
190 					 unsigned selector)
191 {
192 	struct ltq_pinmux_info *info = pinctrl_dev_get_drvdata(pctrldev);
193 
194 	if (selector >= info->num_funcs)
195 		return NULL;
196 
197 	return info->funcs[selector].name;
198 }
199 
200 static int ltq_pmx_get_groups(struct pinctrl_dev *pctrldev,
201 				unsigned func,
202 				const char * const **groups,
203 				unsigned * const num_groups)
204 {
205 	struct ltq_pinmux_info *info = pinctrl_dev_get_drvdata(pctrldev);
206 
207 	*groups = info->funcs[func].groups;
208 	*num_groups = info->funcs[func].num_groups;
209 
210 	return 0;
211 }
212 
213 /* Return function number. If failure, return negative value. */
214 static int match_mux(const struct ltq_mfp_pin *mfp, unsigned mux)
215 {
216 	int i;
217 	for (i = 0; i < LTQ_MAX_MUX; i++) {
218 		if (mfp->func[i] == mux)
219 			break;
220 	}
221 	if (i >= LTQ_MAX_MUX)
222 		return -EINVAL;
223 	return i;
224 }
225 
226 /* dont assume .mfp is linearly mapped. find the mfp with the correct .pin */
227 static int match_mfp(const struct ltq_pinmux_info *info, int pin)
228 {
229 	int i;
230 	for (i = 0; i < info->num_mfp; i++) {
231 		if (info->mfp[i].pin == pin)
232 			return i;
233 	}
234 	return -1;
235 }
236 
237 /* check whether current pin configuration is valid. Negative for failure */
238 static int match_group_mux(const struct ltq_pin_group *grp,
239 			   const struct ltq_pinmux_info *info,
240 			   unsigned mux)
241 {
242 	int i, pin, ret = 0;
243 	for (i = 0; i < grp->npins; i++) {
244 		pin = match_mfp(info, grp->pins[i]);
245 		if (pin < 0) {
246 			dev_err(info->dev, "could not find mfp for pin %d\n",
247 				grp->pins[i]);
248 			return -EINVAL;
249 		}
250 		ret = match_mux(&info->mfp[pin], mux);
251 		if (ret < 0) {
252 			dev_err(info->dev, "Can't find mux %d on pin%d\n",
253 				mux, pin);
254 			break;
255 		}
256 	}
257 	return ret;
258 }
259 
260 static int ltq_pmx_set(struct pinctrl_dev *pctrldev,
261 		       unsigned func,
262 		       unsigned group)
263 {
264 	struct ltq_pinmux_info *info = pinctrl_dev_get_drvdata(pctrldev);
265 	const struct ltq_pin_group *pin_grp = &info->grps[group];
266 	int i, pin, pin_func, ret;
267 
268 	if (!pin_grp->npins ||
269 		(match_group_mux(pin_grp, info, pin_grp->mux) < 0)) {
270 		dev_err(info->dev, "Failed to set the pin group: %s\n",
271 			info->grps[group].name);
272 		return -EINVAL;
273 	}
274 	for (i = 0; i < pin_grp->npins; i++) {
275 		pin = match_mfp(info, pin_grp->pins[i]);
276 		if (pin < 0) {
277 			dev_err(info->dev, "could not find mfp for pin %d\n",
278 				pin_grp->pins[i]);
279 			return -EINVAL;
280 		}
281 		pin_func = match_mux(&info->mfp[pin], pin_grp->mux);
282 		ret = info->apply_mux(pctrldev, pin, pin_func);
283 		if (ret) {
284 			dev_err(info->dev,
285 				"failed to apply mux %d for pin %d\n",
286 				pin_func, pin);
287 			return ret;
288 		}
289 	}
290 	return 0;
291 }
292 
293 static int ltq_pmx_gpio_request_enable(struct pinctrl_dev *pctrldev,
294 				struct pinctrl_gpio_range *range,
295 				unsigned pin)
296 {
297 	struct ltq_pinmux_info *info = pinctrl_dev_get_drvdata(pctrldev);
298 	int mfp = match_mfp(info, pin);
299 	int pin_func;
300 
301 	if (mfp < 0) {
302 		dev_err(info->dev, "could not find mfp for pin %d\n", pin);
303 		return -EINVAL;
304 	}
305 
306 	pin_func = match_mux(&info->mfp[mfp], 0);
307 	if (pin_func < 0) {
308 		dev_err(info->dev, "No GPIO function on pin%d\n", mfp);
309 		return -EINVAL;
310 	}
311 
312 	return info->apply_mux(pctrldev, mfp, pin_func);
313 }
314 
315 static const struct pinmux_ops ltq_pmx_ops = {
316 	.get_functions_count	= ltq_pmx_func_count,
317 	.get_function_name	= ltq_pmx_func_name,
318 	.get_function_groups	= ltq_pmx_get_groups,
319 	.set_mux		= ltq_pmx_set,
320 	.gpio_request_enable	= ltq_pmx_gpio_request_enable,
321 };
322 
323 /*
324  * allow different socs to register with the generic part of the lanti
325  * pinctrl code
326  */
327 int ltq_pinctrl_register(struct platform_device *pdev,
328 				struct ltq_pinmux_info *info)
329 {
330 	struct pinctrl_desc *desc;
331 
332 	if (!info)
333 		return -EINVAL;
334 	desc = info->desc;
335 	desc->pctlops = &ltq_pctrl_ops;
336 	desc->pmxops = &ltq_pmx_ops;
337 	info->dev = &pdev->dev;
338 
339 	info->pctrl = devm_pinctrl_register(&pdev->dev, desc, info);
340 	if (IS_ERR(info->pctrl)) {
341 		dev_err(&pdev->dev, "failed to register LTQ pinmux driver\n");
342 		return PTR_ERR(info->pctrl);
343 	}
344 	platform_set_drvdata(pdev, info);
345 	return 0;
346 }
347