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			return ret;
162
163		ret = of_property_count_strings(np, "st,pins");
164		if (ret < 0)
165			return ret;
166
167		count += ret;
168	}
169
170	if (!count) {
171		dev_err(pmx->dev, "No child nodes passed via DT\n");
172		return -ENODEV;
173	}
174
175	*map = kzalloc(sizeof(**map) * count, GFP_KERNEL);
176	if (!*map)
177		return -ENOMEM;
178
179	for_each_child_of_node(np_config, np) {
180		of_property_read_string(np, "st,function", &function);
181		of_property_for_each_string(np, "st,pins", prop, group) {
182			(*map)[index].type = PIN_MAP_TYPE_MUX_GROUP;
183			(*map)[index].data.mux.group = group;
184			(*map)[index].data.mux.function = function;
185			index++;
186		}
187	}
188
189	*num_maps = count;
190
191	return 0;
192}
193
194static void spear_pinctrl_dt_free_map(struct pinctrl_dev *pctldev,
195				      struct pinctrl_map *map,
196				      unsigned num_maps)
197{
198	kfree(map);
199}
200
201static const struct pinctrl_ops spear_pinctrl_ops = {
202	.get_groups_count = spear_pinctrl_get_groups_cnt,
203	.get_group_name = spear_pinctrl_get_group_name,
204	.get_group_pins = spear_pinctrl_get_group_pins,
205	.pin_dbg_show = spear_pinctrl_pin_dbg_show,
206	.dt_node_to_map = spear_pinctrl_dt_node_to_map,
207	.dt_free_map = spear_pinctrl_dt_free_map,
208};
209
210static int spear_pinctrl_get_funcs_count(struct pinctrl_dev *pctldev)
211{
212	struct spear_pmx *pmx = pinctrl_dev_get_drvdata(pctldev);
213
214	return pmx->machdata->nfunctions;
215}
216
217static const char *spear_pinctrl_get_func_name(struct pinctrl_dev *pctldev,
218		unsigned function)
219{
220	struct spear_pmx *pmx = pinctrl_dev_get_drvdata(pctldev);
221
222	return pmx->machdata->functions[function]->name;
223}
224
225static int spear_pinctrl_get_func_groups(struct pinctrl_dev *pctldev,
226		unsigned function, const char *const **groups,
227		unsigned * const ngroups)
228{
229	struct spear_pmx *pmx = pinctrl_dev_get_drvdata(pctldev);
230
231	*groups = pmx->machdata->functions[function]->groups;
232	*ngroups = pmx->machdata->functions[function]->ngroups;
233
234	return 0;
235}
236
237static int spear_pinctrl_endisable(struct pinctrl_dev *pctldev,
238		unsigned function, unsigned group, bool enable)
239{
240	struct spear_pmx *pmx = pinctrl_dev_get_drvdata(pctldev);
241	const struct spear_pingroup *pgroup;
242	const struct spear_modemux *modemux;
243	int i;
244	bool found = false;
245
246	pgroup = pmx->machdata->groups[group];
247
248	for (i = 0; i < pgroup->nmodemuxs; i++) {
249		modemux = &pgroup->modemuxs[i];
250
251		/* SoC have any modes */
252		if (pmx->machdata->modes_supported) {
253			if (!(pmx->machdata->mode & modemux->modes))
254				continue;
255		}
256
257		found = true;
258		muxregs_endisable(pmx, modemux->muxregs, modemux->nmuxregs,
259				enable);
260	}
261
262	if (!found) {
263		dev_err(pmx->dev, "pinmux group: %s not supported\n",
264				pgroup->name);
265		return -ENODEV;
266	}
267
268	return 0;
269}
270
271static int spear_pinctrl_set_mux(struct pinctrl_dev *pctldev, unsigned function,
272		unsigned group)
273{
274	return spear_pinctrl_endisable(pctldev, function, group, true);
275}
276
277/* gpio with pinmux */
278static struct spear_gpio_pingroup *get_gpio_pingroup(struct spear_pmx *pmx,
279		unsigned pin)
280{
281	struct spear_gpio_pingroup *gpio_pingroup;
282	int i, j;
283
284	if (!pmx->machdata->gpio_pingroups)
285		return NULL;
286
287	for (i = 0; i < pmx->machdata->ngpio_pingroups; i++) {
288		gpio_pingroup = &pmx->machdata->gpio_pingroups[i];
289
290		for (j = 0; j < gpio_pingroup->npins; j++) {
291			if (gpio_pingroup->pins[j] == pin)
292				return gpio_pingroup;
293		}
294	}
295
296	return NULL;
297}
298
299static int gpio_request_endisable(struct pinctrl_dev *pctldev,
300		struct pinctrl_gpio_range *range, unsigned offset, bool enable)
301{
302	struct spear_pmx *pmx = pinctrl_dev_get_drvdata(pctldev);
303	struct spear_pinctrl_machdata *machdata = pmx->machdata;
304	struct spear_gpio_pingroup *gpio_pingroup;
305
306	/*
307	 * Some SoC have configuration options applicable to group of pins,
308	 * rather than a single pin.
309	 */
310	gpio_pingroup = get_gpio_pingroup(pmx, offset);
311	if (gpio_pingroup)
312		muxregs_endisable(pmx, gpio_pingroup->muxregs,
313				gpio_pingroup->nmuxregs, enable);
314
315	/*
316	 * SoC may need some extra configurations, or configurations for single
317	 * pin
318	 */
319	if (machdata->gpio_request_endisable)
320		machdata->gpio_request_endisable(pmx, offset, enable);
321
322	return 0;
323}
324
325static int gpio_request_enable(struct pinctrl_dev *pctldev,
326		struct pinctrl_gpio_range *range, unsigned offset)
327{
328	return gpio_request_endisable(pctldev, range, offset, true);
329}
330
331static void gpio_disable_free(struct pinctrl_dev *pctldev,
332		struct pinctrl_gpio_range *range, unsigned offset)
333{
334	gpio_request_endisable(pctldev, range, offset, false);
335}
336
337static const struct pinmux_ops spear_pinmux_ops = {
338	.get_functions_count = spear_pinctrl_get_funcs_count,
339	.get_function_name = spear_pinctrl_get_func_name,
340	.get_function_groups = spear_pinctrl_get_func_groups,
341	.set_mux = spear_pinctrl_set_mux,
342	.gpio_request_enable = gpio_request_enable,
343	.gpio_disable_free = gpio_disable_free,
344};
345
346static struct pinctrl_desc spear_pinctrl_desc = {
347	.name = DRIVER_NAME,
348	.pctlops = &spear_pinctrl_ops,
349	.pmxops = &spear_pinmux_ops,
350	.owner = THIS_MODULE,
351};
352
353int spear_pinctrl_probe(struct platform_device *pdev,
354			struct spear_pinctrl_machdata *machdata)
355{
356	struct device_node *np = pdev->dev.of_node;
357	struct resource *res;
358	struct spear_pmx *pmx;
359
360	if (!machdata)
361		return -ENODEV;
362
363	pmx = devm_kzalloc(&pdev->dev, sizeof(*pmx), GFP_KERNEL);
364	if (!pmx) {
365		dev_err(&pdev->dev, "Can't alloc spear_pmx\n");
366		return -ENOMEM;
367	}
368
369	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
370	pmx->vbase = devm_ioremap_resource(&pdev->dev, res);
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 = pinctrl_register(&spear_pinctrl_desc, &pdev->dev, 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
407int spear_pinctrl_remove(struct platform_device *pdev)
408{
409	struct spear_pmx *pmx = platform_get_drvdata(pdev);
410
411	pinctrl_unregister(pmx->pctl);
412
413	return 0;
414}
415