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