pinctrl-spear.c

  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 property *prop;
155	const char *function, *group;
156	int ret, index = 0, count = 0;
157
158	/* calculate number of maps required */
159	for_each_child_of_node_scoped(np_config, np) {
160		ret = of_property_read_string(np, "st,function", &function);
161		if (ret < 0)
162			return ret;
163
164		ret = of_property_count_strings(np, "st,pins");
165		if (ret < 0)
166			return ret;
167
168		count += ret;
169	}
170
171	if (!count) {
172		dev_err(pmx->dev, "No child nodes passed via DT\n");
173		return -ENODEV;
174	}
175
176	*map = kcalloc(count, sizeof(**map), GFP_KERNEL);
177	if (!*map)
178		return -ENOMEM;
179
180	for_each_child_of_node_scoped(np_config, np) {
181		of_property_read_string(np, "st,function", &function);
182		of_property_for_each_string(np, "st,pins", prop, group) {
183			(*map)[index].type = PIN_MAP_TYPE_MUX_GROUP;
184			(*map)[index].data.mux.group = group;
185			(*map)[index].data.mux.function = function;
186			index++;
187		}
188	}
189
190	*num_maps = count;
191
192	return 0;
193}
194
195static void spear_pinctrl_dt_free_map(struct pinctrl_dev *pctldev,
196				      struct pinctrl_map *map,
197				      unsigned num_maps)
198{
199	kfree(map);
200}
201
202static const struct pinctrl_ops spear_pinctrl_ops = {
203	.get_groups_count = spear_pinctrl_get_groups_cnt,
204	.get_group_name = spear_pinctrl_get_group_name,
205	.get_group_pins = spear_pinctrl_get_group_pins,
206	.pin_dbg_show = spear_pinctrl_pin_dbg_show,
207	.dt_node_to_map = spear_pinctrl_dt_node_to_map,
208	.dt_free_map = spear_pinctrl_dt_free_map,
209};
210
211static int spear_pinctrl_get_funcs_count(struct pinctrl_dev *pctldev)
212{
213	struct spear_pmx *pmx = pinctrl_dev_get_drvdata(pctldev);
214
215	return pmx->machdata->nfunctions;
216}
217
218static const char *spear_pinctrl_get_func_name(struct pinctrl_dev *pctldev,
219		unsigned function)
220{
221	struct spear_pmx *pmx = pinctrl_dev_get_drvdata(pctldev);
222
223	return pmx->machdata->functions[function]->name;
224}
225
226static int spear_pinctrl_get_func_groups(struct pinctrl_dev *pctldev,
227		unsigned function, const char *const **groups,
228		unsigned * const ngroups)
229{
230	struct spear_pmx *pmx = pinctrl_dev_get_drvdata(pctldev);
231
232	*groups = pmx->machdata->functions[function]->groups;
233	*ngroups = pmx->machdata->functions[function]->ngroups;
234
235	return 0;
236}
237
238static int spear_pinctrl_endisable(struct pinctrl_dev *pctldev,
239		unsigned function, unsigned group, bool enable)
240{
241	struct spear_pmx *pmx = pinctrl_dev_get_drvdata(pctldev);
242	const struct spear_pingroup *pgroup;
243	const struct spear_modemux *modemux;
244	int i;
245	bool found = false;
246
247	pgroup = pmx->machdata->groups[group];
248
249	for (i = 0; i < pgroup->nmodemuxs; i++) {
250		modemux = &pgroup->modemuxs[i];
251
252		/* SoC have any modes */
253		if (pmx->machdata->modes_supported) {
254			if (!(pmx->machdata->mode & modemux->modes))
255				continue;
256		}
257
258		found = true;
259		muxregs_endisable(pmx, modemux->muxregs, modemux->nmuxregs,
260				enable);
261	}
262
263	if (!found) {
264		dev_err(pmx->dev, "pinmux group: %s not supported\n",
265				pgroup->name);
266		return -ENODEV;
267	}
268
269	return 0;
270}
271
272static int spear_pinctrl_set_mux(struct pinctrl_dev *pctldev, unsigned function,
273		unsigned group)
274{
275	return spear_pinctrl_endisable(pctldev, function, group, true);
276}
277
278/* gpio with pinmux */
279static struct spear_gpio_pingroup *get_gpio_pingroup(struct spear_pmx *pmx,
280		unsigned pin)
281{
282	struct spear_gpio_pingroup *gpio_pingroup;
283	int i, j;
284
285	if (!pmx->machdata->gpio_pingroups)
286		return NULL;
287
288	for (i = 0; i < pmx->machdata->ngpio_pingroups; i++) {
289		gpio_pingroup = &pmx->machdata->gpio_pingroups[i];
290
291		for (j = 0; j < gpio_pingroup->npins; j++) {
292			if (gpio_pingroup->pins[j] == pin)
293				return gpio_pingroup;
294		}
295	}
296
297	return NULL;
298}
299
300static int gpio_request_endisable(struct pinctrl_dev *pctldev,
301		struct pinctrl_gpio_range *range, unsigned offset, bool enable)
302{
303	struct spear_pmx *pmx = pinctrl_dev_get_drvdata(pctldev);
304	struct spear_pinctrl_machdata *machdata = pmx->machdata;
305	struct spear_gpio_pingroup *gpio_pingroup;
306
307	/*
308	 * Some SoC have configuration options applicable to group of pins,
309	 * rather than a single pin.
310	 */
311	gpio_pingroup = get_gpio_pingroup(pmx, offset);
312	if (gpio_pingroup)
313		muxregs_endisable(pmx, gpio_pingroup->muxregs,
314				gpio_pingroup->nmuxregs, enable);
315
316	/*
317	 * SoC may need some extra configurations, or configurations for single
318	 * pin
319	 */
320	if (machdata->gpio_request_endisable)
321		machdata->gpio_request_endisable(pmx, offset, enable);
322
323	return 0;
324}
325
326static int gpio_request_enable(struct pinctrl_dev *pctldev,
327		struct pinctrl_gpio_range *range, unsigned offset)
328{
329	return gpio_request_endisable(pctldev, range, offset, true);
330}
331
332static void gpio_disable_free(struct pinctrl_dev *pctldev,
333		struct pinctrl_gpio_range *range, unsigned offset)
334{
335	gpio_request_endisable(pctldev, range, offset, false);
336}
337
338static const struct pinmux_ops spear_pinmux_ops = {
339	.get_functions_count = spear_pinctrl_get_funcs_count,
340	.get_function_name = spear_pinctrl_get_func_name,
341	.get_function_groups = spear_pinctrl_get_func_groups,
342	.set_mux = spear_pinctrl_set_mux,
343	.gpio_request_enable = gpio_request_enable,
344	.gpio_disable_free = gpio_disable_free,
345};
346
347static struct pinctrl_desc spear_pinctrl_desc = {
348	.name = DRIVER_NAME,
349	.pctlops = &spear_pinctrl_ops,
350	.pmxops = &spear_pinmux_ops,
351	.owner = THIS_MODULE,
352};
353
354int spear_pinctrl_probe(struct platform_device *pdev,
355			struct spear_pinctrl_machdata *machdata)
356{
357	struct device_node *np = pdev->dev.of_node;
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		return -ENOMEM;
366
367	pmx->regmap = device_node_to_regmap(np);
368	if (IS_ERR(pmx->regmap)) {
369		dev_err(&pdev->dev, "Init regmap failed (%pe).\n",
370			pmx->regmap);
371		return PTR_ERR(pmx->regmap);
372	}
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}