1/*
2 * Driver for the ST Microelectronics SPEAr pinmux
3 *
4 * Copyright (C) 2012 ST Microelectronics
5 * Viresh Kumar <vireshk@kernel.org>
6 *
7 * Inspired from:
8 * - U300 Pinctl drivers
9 * - Tegra Pinctl drivers
10 *
11 * This file is licensed under the terms of the GNU General Public
12 * License version 2. This program is licensed "as is" without any
13 * warranty of any kind, whether express or implied.
14 */
15
16#include <linux/err.h>
17#include <linux/mfd/syscon.h>
18#include <linux/module.h>
19#include <linux/of.h>
20#include <linux/of_address.h>
21#include <linux/platform_device.h>
22#include <linux/seq_file.h>
23#include <linux/slab.h>
24
25#include <linux/pinctrl/machine.h>
26#include <linux/pinctrl/pinctrl.h>
27#include <linux/pinctrl/pinmux.h>
28
29#include "pinctrl-spear.h"
30
31#define DRIVER_NAME "spear-pinmux"
32
33static void muxregs_endisable(struct spear_pmx *pmx,
34		struct spear_muxreg *muxregs, u8 count, bool enable)
35{
36	struct spear_muxreg *muxreg;
37	u32 val, temp, j;
38
39	for (j = 0; j < count; j++) {
40		muxreg = &muxregs[j];
41
42		val = pmx_readl(pmx, muxreg->reg);
43		val &= ~muxreg->mask;
44
45		if (enable)
46			temp = muxreg->val;
47		else
48			temp = ~muxreg->val;
49
50		val |= muxreg->mask & temp;
51		pmx_writel(pmx, val, muxreg->reg);
52	}
53}
54
55static int set_mode(struct spear_pmx *pmx, int mode)
56{
57	struct spear_pmx_mode *pmx_mode = NULL;
58	int i;
59	u32 val;
60
61	if (!pmx->machdata->pmx_modes || !pmx->machdata->npmx_modes)
62		return -EINVAL;
63
64	for (i = 0; i < pmx->machdata->npmx_modes; i++) {
65		if (pmx->machdata->pmx_modes[i]->mode == (1 << mode)) {
66			pmx_mode = pmx->machdata->pmx_modes[i];
67			break;
68		}
69	}
70
71	if (!pmx_mode)
72		return -EINVAL;
73
74	val = pmx_readl(pmx, pmx_mode->reg);
75	val &= ~pmx_mode->mask;
76	val |= pmx_mode->val;
77	pmx_writel(pmx, val, pmx_mode->reg);
78
79	pmx->machdata->mode = pmx_mode->mode;
80	dev_info(pmx->dev, "Configured Mode: %s with id: %x\n\n",
81			pmx_mode->name ? pmx_mode->name : "no_name",
82			pmx_mode->reg);
83
84	return 0;
85}
86
87void pmx_init_gpio_pingroup_addr(struct spear_gpio_pingroup *gpio_pingroup,
88				 unsigned count, u16 reg)
89{
90	int i, j;
91
92	for (i = 0; i < count; i++)
93		for (j = 0; j < gpio_pingroup[i].nmuxregs; j++)
94			gpio_pingroup[i].muxregs[j].reg = reg;
95}
96
97void pmx_init_addr(struct spear_pinctrl_machdata *machdata, u16 reg)
98{
99	struct spear_pingroup *pgroup;
100	struct spear_modemux *modemux;
101	int i, j, group;
102
103	for (group = 0; group < machdata->ngroups; group++) {
104		pgroup = machdata->groups[group];
105
106		for (i = 0; i < pgroup->nmodemuxs; i++) {
107			modemux = &pgroup->modemuxs[i];
108
109			for (j = 0; j < modemux->nmuxregs; j++)
110				if (modemux->muxregs[j].reg == 0xFFFF)
111					modemux->muxregs[j].reg = reg;
112		}
113	}
114}
115
116static int spear_pinctrl_get_groups_cnt(struct pinctrl_dev *pctldev)
117{
118	struct spear_pmx *pmx = pinctrl_dev_get_drvdata(pctldev);
119
120	return pmx->machdata->ngroups;
121}
122
123static const char *spear_pinctrl_get_group_name(struct pinctrl_dev *pctldev,
124		unsigned group)
125{
126	struct spear_pmx *pmx = pinctrl_dev_get_drvdata(pctldev);
127
128	return pmx->machdata->groups[group]->name;
129}
130
131static int spear_pinctrl_get_group_pins(struct pinctrl_dev *pctldev,
132		unsigned group, const unsigned **pins, unsigned *num_pins)
133{
134	struct spear_pmx *pmx = pinctrl_dev_get_drvdata(pctldev);
135
136	*pins = pmx->machdata->groups[group]->pins;
137	*num_pins = pmx->machdata->groups[group]->npins;
138
139	return 0;
140}
141
142static void spear_pinctrl_pin_dbg_show(struct pinctrl_dev *pctldev,
143		struct seq_file *s, unsigned offset)
144{
145	seq_printf(s, " " DRIVER_NAME);
146}
147
148static int spear_pinctrl_dt_node_to_map(struct pinctrl_dev *pctldev,
149					struct device_node *np_config,
150					struct pinctrl_map **map,
151					unsigned *num_maps)
152{
153	struct spear_pmx *pmx = pinctrl_dev_get_drvdata(pctldev);
154	struct device_node *np;
155	struct property *prop;
156	const char *function, *group;
157	int ret, index = 0, count = 0;
158
159	/* calculate number of maps required */
160	for_each_child_of_node(np_config, np) {
161		ret = of_property_read_string(np, "st,function", &function);
162		if (ret < 0) {
163			of_node_put(np);
164			return ret;
165		}
166
167		ret = of_property_count_strings(np, "st,pins");
168		if (ret < 0) {
169			of_node_put(np);
170			return ret;
171		}
172
173		count += ret;
174	}
175
176	if (!count) {
177		dev_err(pmx->dev, "No child nodes passed via DT\n");
178		return -ENODEV;
179	}
180
181	*map = kcalloc(count, sizeof(**map), GFP_KERNEL);
182	if (!*map)
183		return -ENOMEM;
184
185	for_each_child_of_node(np_config, np) {
186		of_property_read_string(np, "st,function", &function);
187		of_property_for_each_string(np, "st,pins", prop, group) {
188			(*map)[index].type = PIN_MAP_TYPE_MUX_GROUP;
189			(*map)[index].data.mux.group = group;
190			(*map)[index].data.mux.function = function;
191			index++;
192		}
193	}
194
195	*num_maps = count;
196
197	return 0;
198}
199
200static void spear_pinctrl_dt_free_map(struct pinctrl_dev *pctldev,
201				      struct pinctrl_map *map,
202				      unsigned num_maps)
203{
204	kfree(map);
205}
206
207static const struct pinctrl_ops spear_pinctrl_ops = {
208	.get_groups_count = spear_pinctrl_get_groups_cnt,
209	.get_group_name = spear_pinctrl_get_group_name,
210	.get_group_pins = spear_pinctrl_get_group_pins,
211	.pin_dbg_show = spear_pinctrl_pin_dbg_show,
212	.dt_node_to_map = spear_pinctrl_dt_node_to_map,
213	.dt_free_map = spear_pinctrl_dt_free_map,
214};
215
216static int spear_pinctrl_get_funcs_count(struct pinctrl_dev *pctldev)
217{
218	struct spear_pmx *pmx = pinctrl_dev_get_drvdata(pctldev);
219
220	return pmx->machdata->nfunctions;
221}
222
223static const char *spear_pinctrl_get_func_name(struct pinctrl_dev *pctldev,
224		unsigned function)
225{
226	struct spear_pmx *pmx = pinctrl_dev_get_drvdata(pctldev);
227
228	return pmx->machdata->functions[function]->name;
229}
230
231static int spear_pinctrl_get_func_groups(struct pinctrl_dev *pctldev,
232		unsigned function, const char *const **groups,
233		unsigned * const ngroups)
234{
235	struct spear_pmx *pmx = pinctrl_dev_get_drvdata(pctldev);
236
237	*groups = pmx->machdata->functions[function]->groups;
238	*ngroups = pmx->machdata->functions[function]->ngroups;
239
240	return 0;
241}
242
243static int spear_pinctrl_endisable(struct pinctrl_dev *pctldev,
244		unsigned function, unsigned group, bool enable)
245{
246	struct spear_pmx *pmx = pinctrl_dev_get_drvdata(pctldev);
247	const struct spear_pingroup *pgroup;
248	const struct spear_modemux *modemux;
249	int i;
250	bool found = false;
251
252	pgroup = pmx->machdata->groups[group];
253
254	for (i = 0; i < pgroup->nmodemuxs; i++) {
255		modemux = &pgroup->modemuxs[i];
256
257		/* SoC have any modes */
258		if (pmx->machdata->modes_supported) {
259			if (!(pmx->machdata->mode & modemux->modes))
260				continue;
261		}
262
263		found = true;
264		muxregs_endisable(pmx, modemux->muxregs, modemux->nmuxregs,
265				enable);
266	}
267
268	if (!found) {
269		dev_err(pmx->dev, "pinmux group: %s not supported\n",
270				pgroup->name);
271		return -ENODEV;
272	}
273
274	return 0;
275}
276
277static int spear_pinctrl_set_mux(struct pinctrl_dev *pctldev, unsigned function,
278		unsigned group)
279{
280	return spear_pinctrl_endisable(pctldev, function, group, true);
281}
282
283/* gpio with pinmux */
284static struct spear_gpio_pingroup *get_gpio_pingroup(struct spear_pmx *pmx,
285		unsigned pin)
286{
287	struct spear_gpio_pingroup *gpio_pingroup;
288	int i, j;
289
290	if (!pmx->machdata->gpio_pingroups)
291		return NULL;
292
293	for (i = 0; i < pmx->machdata->ngpio_pingroups; i++) {
294		gpio_pingroup = &pmx->machdata->gpio_pingroups[i];
295
296		for (j = 0; j < gpio_pingroup->npins; j++) {
297			if (gpio_pingroup->pins[j] == pin)
298				return gpio_pingroup;
299		}
300	}
301
302	return NULL;
303}
304
305static int gpio_request_endisable(struct pinctrl_dev *pctldev,
306		struct pinctrl_gpio_range *range, unsigned offset, bool enable)
307{
308	struct spear_pmx *pmx = pinctrl_dev_get_drvdata(pctldev);
309	struct spear_pinctrl_machdata *machdata = pmx->machdata;
310	struct spear_gpio_pingroup *gpio_pingroup;
311
312	/*
313	 * Some SoC have configuration options applicable to group of pins,
314	 * rather than a single pin.
315	 */
316	gpio_pingroup = get_gpio_pingroup(pmx, offset);
317	if (gpio_pingroup)
318		muxregs_endisable(pmx, gpio_pingroup->muxregs,
319				gpio_pingroup->nmuxregs, enable);
320
321	/*
322	 * SoC may need some extra configurations, or configurations for single
323	 * pin
324	 */
325	if (machdata->gpio_request_endisable)
326		machdata->gpio_request_endisable(pmx, offset, enable);
327
328	return 0;
329}
330
331static int gpio_request_enable(struct pinctrl_dev *pctldev,
332		struct pinctrl_gpio_range *range, unsigned offset)
333{
334	return gpio_request_endisable(pctldev, range, offset, true);
335}
336
337static void gpio_disable_free(struct pinctrl_dev *pctldev,
338		struct pinctrl_gpio_range *range, unsigned offset)
339{
340	gpio_request_endisable(pctldev, range, offset, false);
341}
342
343static const struct pinmux_ops spear_pinmux_ops = {
344	.get_functions_count = spear_pinctrl_get_funcs_count,
345	.get_function_name = spear_pinctrl_get_func_name,
346	.get_function_groups = spear_pinctrl_get_func_groups,
347	.set_mux = spear_pinctrl_set_mux,
348	.gpio_request_enable = gpio_request_enable,
349	.gpio_disable_free = gpio_disable_free,
350};
351
352static struct pinctrl_desc spear_pinctrl_desc = {
353	.name = DRIVER_NAME,
354	.pctlops = &spear_pinctrl_ops,
355	.pmxops = &spear_pinmux_ops,
356	.owner = THIS_MODULE,
357};
358
359int spear_pinctrl_probe(struct platform_device *pdev,
360			struct spear_pinctrl_machdata *machdata)
361{
362	struct device_node *np = pdev->dev.of_node;
363	struct spear_pmx *pmx;
364
365	if (!machdata)
366		return -ENODEV;
367
368	pmx = devm_kzalloc(&pdev->dev, sizeof(*pmx), GFP_KERNEL);
369	if (!pmx)
370		return -ENOMEM;
371
372	pmx->regmap = device_node_to_regmap(np);
373	if (IS_ERR(pmx->regmap)) {
374		dev_err(&pdev->dev, "Init regmap failed (%pe).\n",
375			pmx->regmap);
376		return PTR_ERR(pmx->regmap);
377	}
378
379	pmx->dev = &pdev->dev;
380	pmx->machdata = machdata;
381
382	/* configure mode, if supported by SoC */
383	if (machdata->modes_supported) {
384		int mode = 0;
385
386		if (of_property_read_u32(np, "st,pinmux-mode", &mode)) {
387			dev_err(&pdev->dev, "OF: pinmux mode not passed\n");
388			return -EINVAL;
389		}
390
391		if (set_mode(pmx, mode)) {
392			dev_err(&pdev->dev, "OF: Couldn't configure mode: %x\n",
393					mode);
394			return -EINVAL;
395		}
396	}
397
398	platform_set_drvdata(pdev, pmx);
399
400	spear_pinctrl_desc.pins = machdata->pins;
401	spear_pinctrl_desc.npins = machdata->npins;
402
403	pmx->pctl = devm_pinctrl_register(&pdev->dev, &spear_pinctrl_desc, pmx);
404	if (IS_ERR(pmx->pctl)) {
405		dev_err(&pdev->dev, "Couldn't register pinctrl driver\n");
406		return PTR_ERR(pmx->pctl);
407	}
408
409	return 0;
410}
411