1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Marvell Berlin SoC pinctrl core driver
4 *
5 * Copyright (C) 2014 Marvell Technology Group Ltd.
6 *
7 * Antoine Ténart <antoine.tenart@free-electrons.com>
8 */
9
10#include <linux/io.h>
11#include <linux/mfd/syscon.h>
12#include <linux/module.h>
13#include <linux/of.h>
14#include <linux/of_address.h>
15#include <linux/of_device.h>
16#include <linux/pinctrl/pinctrl.h>
17#include <linux/pinctrl/pinmux.h>
18#include <linux/platform_device.h>
19#include <linux/regmap.h>
20#include <linux/slab.h>
21
22#include "../core.h"
23#include "../pinctrl-utils.h"
24#include "berlin.h"
25
26struct berlin_pinctrl {
27	struct regmap *regmap;
28	struct device *dev;
29	const struct berlin_pinctrl_desc *desc;
30	struct berlin_pinctrl_function *functions;
31	unsigned nfunctions;
32	struct pinctrl_dev *pctrl_dev;
33};
34
35static int berlin_pinctrl_get_group_count(struct pinctrl_dev *pctrl_dev)
36{
37	struct berlin_pinctrl *pctrl = pinctrl_dev_get_drvdata(pctrl_dev);
38
39	return pctrl->desc->ngroups;
40}
41
42static const char *berlin_pinctrl_get_group_name(struct pinctrl_dev *pctrl_dev,
43						 unsigned group)
44{
45	struct berlin_pinctrl *pctrl = pinctrl_dev_get_drvdata(pctrl_dev);
46
47	return pctrl->desc->groups[group].name;
48}
49
50static int berlin_pinctrl_dt_node_to_map(struct pinctrl_dev *pctrl_dev,
51					 struct device_node *node,
52					 struct pinctrl_map **map,
53					 unsigned *num_maps)
54{
55	struct berlin_pinctrl *pctrl = pinctrl_dev_get_drvdata(pctrl_dev);
56	struct property *prop;
57	const char *function_name, *group_name;
58	unsigned reserved_maps = 0;
59	int ret, ngroups;
60
61	*map = NULL;
62	*num_maps = 0;
63
64	ret = of_property_read_string(node, "function", &function_name);
65	if (ret) {
66		dev_err(pctrl->dev,
67			"missing function property in node %pOFn\n", node);
68		return -EINVAL;
69	}
70
71	ngroups = of_property_count_strings(node, "groups");
72	if (ngroups < 0) {
73		dev_err(pctrl->dev,
74			"missing groups property in node %pOFn\n", node);
75		return -EINVAL;
76	}
77
78	ret = pinctrl_utils_reserve_map(pctrl_dev, map, &reserved_maps,
79					num_maps, ngroups);
80	if (ret) {
81		dev_err(pctrl->dev, "can't reserve map: %d\n", ret);
82		return ret;
83	}
84
85	of_property_for_each_string(node, "groups", prop, group_name) {
86		ret = pinctrl_utils_add_map_mux(pctrl_dev, map, &reserved_maps,
87						num_maps, group_name,
88						function_name);
89		if (ret) {
90			dev_err(pctrl->dev, "can't add map: %d\n", ret);
91			return ret;
92		}
93	}
94
95	return 0;
96}
97
98static const struct pinctrl_ops berlin_pinctrl_ops = {
99	.get_groups_count	= &berlin_pinctrl_get_group_count,
100	.get_group_name		= &berlin_pinctrl_get_group_name,
101	.dt_node_to_map		= &berlin_pinctrl_dt_node_to_map,
102	.dt_free_map		= &pinctrl_utils_free_map,
103};
104
105static int berlin_pinmux_get_functions_count(struct pinctrl_dev *pctrl_dev)
106{
107	struct berlin_pinctrl *pctrl = pinctrl_dev_get_drvdata(pctrl_dev);
108
109	return pctrl->nfunctions;
110}
111
112static const char *berlin_pinmux_get_function_name(struct pinctrl_dev *pctrl_dev,
113						   unsigned function)
114{
115	struct berlin_pinctrl *pctrl = pinctrl_dev_get_drvdata(pctrl_dev);
116
117	return pctrl->functions[function].name;
118}
119
120static int berlin_pinmux_get_function_groups(struct pinctrl_dev *pctrl_dev,
121					     unsigned function,
122					     const char * const **groups,
123					     unsigned * const num_groups)
124{
125	struct berlin_pinctrl *pctrl = pinctrl_dev_get_drvdata(pctrl_dev);
126
127	*groups = pctrl->functions[function].groups;
128	*num_groups = pctrl->functions[function].ngroups;
129
130	return 0;
131}
132
133static struct berlin_desc_function *
134berlin_pinctrl_find_function_by_name(struct berlin_pinctrl *pctrl,
135				     const struct berlin_desc_group *group,
136				     const char *fname)
137{
138	struct berlin_desc_function *function = group->functions;
139
140	while (function->name) {
141		if (!strcmp(function->name, fname))
142			return function;
143
144		function++;
145	}
146
147	return NULL;
148}
149
150static int berlin_pinmux_set(struct pinctrl_dev *pctrl_dev,
151			     unsigned function,
152			     unsigned group)
153{
154	struct berlin_pinctrl *pctrl = pinctrl_dev_get_drvdata(pctrl_dev);
155	const struct berlin_desc_group *group_desc = pctrl->desc->groups + group;
156	struct berlin_pinctrl_function *func = pctrl->functions + function;
157	struct berlin_desc_function *function_desc =
158		berlin_pinctrl_find_function_by_name(pctrl, group_desc,
159						     func->name);
160	u32 mask, val;
161
162	if (!function_desc)
163		return -EINVAL;
164
165	mask = GENMASK(group_desc->lsb + group_desc->bit_width - 1,
166		       group_desc->lsb);
167	val = function_desc->muxval << group_desc->lsb;
168	regmap_update_bits(pctrl->regmap, group_desc->offset, mask, val);
169
170	return 0;
171}
172
173static const struct pinmux_ops berlin_pinmux_ops = {
174	.get_functions_count	= &berlin_pinmux_get_functions_count,
175	.get_function_name	= &berlin_pinmux_get_function_name,
176	.get_function_groups	= &berlin_pinmux_get_function_groups,
177	.set_mux		= &berlin_pinmux_set,
178};
179
180static int berlin_pinctrl_add_function(struct berlin_pinctrl *pctrl,
181				       const char *name)
182{
183	struct berlin_pinctrl_function *function = pctrl->functions;
184
185	while (function->name) {
186		if (!strcmp(function->name, name)) {
187			function->ngroups++;
188			return -EEXIST;
189		}
190		function++;
191	}
192
193	function->name = name;
194	function->ngroups = 1;
195
196	pctrl->nfunctions++;
197
198	return 0;
199}
200
201static int berlin_pinctrl_build_state(struct platform_device *pdev)
202{
203	struct berlin_pinctrl *pctrl = platform_get_drvdata(pdev);
204	const struct berlin_desc_group *desc_group;
205	const struct berlin_desc_function *desc_function;
206	int i, max_functions = 0;
207
208	pctrl->nfunctions = 0;
209
210	for (i = 0; i < pctrl->desc->ngroups; i++) {
211		desc_group = pctrl->desc->groups + i;
212		/* compute the maxiumum number of functions a group can have */
213		max_functions += 1 << (desc_group->bit_width + 1);
214	}
215
216	/* we will reallocate later */
217	pctrl->functions = kcalloc(max_functions,
218				   sizeof(*pctrl->functions), GFP_KERNEL);
219	if (!pctrl->functions)
220		return -ENOMEM;
221
222	/* register all functions */
223	for (i = 0; i < pctrl->desc->ngroups; i++) {
224		desc_group = pctrl->desc->groups + i;
225		desc_function = desc_group->functions;
226
227		while (desc_function->name) {
228			berlin_pinctrl_add_function(pctrl, desc_function->name);
229			desc_function++;
230		}
231	}
232
233	pctrl->functions = krealloc(pctrl->functions,
234				    pctrl->nfunctions * sizeof(*pctrl->functions),
235				    GFP_KERNEL);
236
237	/* map functions to theirs groups */
238	for (i = 0; i < pctrl->desc->ngroups; i++) {
239		desc_group = pctrl->desc->groups + i;
240		desc_function = desc_group->functions;
241
242		while (desc_function->name) {
243			struct berlin_pinctrl_function
244				*function = pctrl->functions;
245			const char **groups;
246			bool found = false;
247
248			while (function->name) {
249				if (!strcmp(desc_function->name, function->name)) {
250					found = true;
251					break;
252				}
253				function++;
254			}
255
256			if (!found) {
257				kfree(pctrl->functions);
258				return -EINVAL;
259			}
260
261			if (!function->groups) {
262				function->groups =
263					devm_kcalloc(&pdev->dev,
264						     function->ngroups,
265						     sizeof(char *),
266						     GFP_KERNEL);
267
268				if (!function->groups) {
269					kfree(pctrl->functions);
270					return -ENOMEM;
271				}
272			}
273
274			groups = function->groups;
275			while (*groups)
276				groups++;
277
278			*groups = desc_group->name;
279
280			desc_function++;
281		}
282	}
283
284	return 0;
285}
286
287static struct pinctrl_desc berlin_pctrl_desc = {
288	.name		= "berlin-pinctrl",
289	.pctlops	= &berlin_pinctrl_ops,
290	.pmxops		= &berlin_pinmux_ops,
291	.owner		= THIS_MODULE,
292};
293
294int berlin_pinctrl_probe_regmap(struct platform_device *pdev,
295				const struct berlin_pinctrl_desc *desc,
296				struct regmap *regmap)
297{
298	struct device *dev = &pdev->dev;
299	struct berlin_pinctrl *pctrl;
300	int ret;
301
302	pctrl = devm_kzalloc(dev, sizeof(*pctrl), GFP_KERNEL);
303	if (!pctrl)
304		return -ENOMEM;
305
306	platform_set_drvdata(pdev, pctrl);
307
308	pctrl->regmap = regmap;
309	pctrl->dev = &pdev->dev;
310	pctrl->desc = desc;
311
312	ret = berlin_pinctrl_build_state(pdev);
313	if (ret) {
314		dev_err(dev, "cannot build driver state: %d\n", ret);
315		return ret;
316	}
317
318	pctrl->pctrl_dev = devm_pinctrl_register(dev, &berlin_pctrl_desc,
319						 pctrl);
320	if (IS_ERR(pctrl->pctrl_dev)) {
321		dev_err(dev, "failed to register pinctrl driver\n");
322		return PTR_ERR(pctrl->pctrl_dev);
323	}
324
325	return 0;
326}
327
328int berlin_pinctrl_probe(struct platform_device *pdev,
329			 const struct berlin_pinctrl_desc *desc)
330{
331	struct device *dev = &pdev->dev;
332	struct device_node *parent_np = of_get_parent(dev->of_node);
333	struct regmap *regmap = syscon_node_to_regmap(parent_np);
334
335	of_node_put(parent_np);
336	if (IS_ERR(regmap))
337		return PTR_ERR(regmap);
338
339	return berlin_pinctrl_probe_regmap(pdev, desc, regmap);
340}
341