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