1/*
2 * SuperH Pin Function Controller pinmux support.
3 *
4 * Copyright (C) 2012  Paul Mundt
5 *
6 * This file is subject to the terms and conditions of the GNU General Public
7 * License.  See the file "COPYING" in the main directory of this archive
8 * for more details.
9 */
10
11#define DRV_NAME "sh-pfc"
12
13#include <linux/device.h>
14#include <linux/err.h>
15#include <linux/init.h>
16#include <linux/module.h>
17#include <linux/of.h>
18#include <linux/pinctrl/consumer.h>
19#include <linux/pinctrl/machine.h>
20#include <linux/pinctrl/pinconf.h>
21#include <linux/pinctrl/pinconf-generic.h>
22#include <linux/pinctrl/pinctrl.h>
23#include <linux/pinctrl/pinmux.h>
24#include <linux/slab.h>
25#include <linux/spinlock.h>
26
27#include "core.h"
28#include "../core.h"
29#include "../pinconf.h"
30
31struct sh_pfc_pin_config {
32	u32 type;
33};
34
35struct sh_pfc_pinctrl {
36	struct pinctrl_dev *pctl;
37	struct pinctrl_desc pctl_desc;
38
39	struct sh_pfc *pfc;
40
41	struct pinctrl_pin_desc *pins;
42	struct sh_pfc_pin_config *configs;
43};
44
45static int sh_pfc_get_groups_count(struct pinctrl_dev *pctldev)
46{
47	struct sh_pfc_pinctrl *pmx = pinctrl_dev_get_drvdata(pctldev);
48
49	return pmx->pfc->info->nr_groups;
50}
51
52static const char *sh_pfc_get_group_name(struct pinctrl_dev *pctldev,
53					 unsigned selector)
54{
55	struct sh_pfc_pinctrl *pmx = pinctrl_dev_get_drvdata(pctldev);
56
57	return pmx->pfc->info->groups[selector].name;
58}
59
60static int sh_pfc_get_group_pins(struct pinctrl_dev *pctldev, unsigned selector,
61				 const unsigned **pins, unsigned *num_pins)
62{
63	struct sh_pfc_pinctrl *pmx = pinctrl_dev_get_drvdata(pctldev);
64
65	*pins = pmx->pfc->info->groups[selector].pins;
66	*num_pins = pmx->pfc->info->groups[selector].nr_pins;
67
68	return 0;
69}
70
71static void sh_pfc_pin_dbg_show(struct pinctrl_dev *pctldev, struct seq_file *s,
72				unsigned offset)
73{
74	seq_printf(s, "%s", DRV_NAME);
75}
76
77#ifdef CONFIG_OF
78static int sh_pfc_map_add_config(struct pinctrl_map *map,
79				 const char *group_or_pin,
80				 enum pinctrl_map_type type,
81				 unsigned long *configs,
82				 unsigned int num_configs)
83{
84	unsigned long *cfgs;
85
86	cfgs = kmemdup(configs, num_configs * sizeof(*cfgs),
87		       GFP_KERNEL);
88	if (cfgs == NULL)
89		return -ENOMEM;
90
91	map->type = type;
92	map->data.configs.group_or_pin = group_or_pin;
93	map->data.configs.configs = cfgs;
94	map->data.configs.num_configs = num_configs;
95
96	return 0;
97}
98
99static int sh_pfc_dt_subnode_to_map(struct device *dev, struct device_node *np,
100				    struct pinctrl_map **map,
101				    unsigned int *num_maps, unsigned int *index)
102{
103	struct pinctrl_map *maps = *map;
104	unsigned int nmaps = *num_maps;
105	unsigned int idx = *index;
106	unsigned int num_configs;
107	const char *function = NULL;
108	unsigned long *configs;
109	struct property *prop;
110	unsigned int num_groups;
111	unsigned int num_pins;
112	const char *group;
113	const char *pin;
114	int ret;
115
116	/* Parse the function and configuration properties. At least a function
117	 * or one configuration must be specified.
118	 */
119	ret = of_property_read_string(np, "renesas,function", &function);
120	if (ret < 0 && ret != -EINVAL) {
121		dev_err(dev, "Invalid function in DT\n");
122		return ret;
123	}
124
125	ret = pinconf_generic_parse_dt_config(np, NULL, &configs, &num_configs);
126	if (ret < 0)
127		return ret;
128
129	if (!function && num_configs == 0) {
130		dev_err(dev,
131			"DT node must contain at least a function or config\n");
132		goto done;
133	}
134
135	/* Count the number of pins and groups and reallocate mappings. */
136	ret = of_property_count_strings(np, "renesas,pins");
137	if (ret == -EINVAL) {
138		num_pins = 0;
139	} else if (ret < 0) {
140		dev_err(dev, "Invalid pins list in DT\n");
141		goto done;
142	} else {
143		num_pins = ret;
144	}
145
146	ret = of_property_count_strings(np, "renesas,groups");
147	if (ret == -EINVAL) {
148		num_groups = 0;
149	} else if (ret < 0) {
150		dev_err(dev, "Invalid pin groups list in DT\n");
151		goto done;
152	} else {
153		num_groups = ret;
154	}
155
156	if (!num_pins && !num_groups) {
157		dev_err(dev, "No pin or group provided in DT node\n");
158		ret = -ENODEV;
159		goto done;
160	}
161
162	if (function)
163		nmaps += num_groups;
164	if (configs)
165		nmaps += num_pins + num_groups;
166
167	maps = krealloc(maps, sizeof(*maps) * nmaps, GFP_KERNEL);
168	if (maps == NULL) {
169		ret = -ENOMEM;
170		goto done;
171	}
172
173	*map = maps;
174	*num_maps = nmaps;
175
176	/* Iterate over pins and groups and create the mappings. */
177	of_property_for_each_string(np, "renesas,groups", prop, group) {
178		if (function) {
179			maps[idx].type = PIN_MAP_TYPE_MUX_GROUP;
180			maps[idx].data.mux.group = group;
181			maps[idx].data.mux.function = function;
182			idx++;
183		}
184
185		if (configs) {
186			ret = sh_pfc_map_add_config(&maps[idx], group,
187						    PIN_MAP_TYPE_CONFIGS_GROUP,
188						    configs, num_configs);
189			if (ret < 0)
190				goto done;
191
192			idx++;
193		}
194	}
195
196	if (!configs) {
197		ret = 0;
198		goto done;
199	}
200
201	of_property_for_each_string(np, "renesas,pins", prop, pin) {
202		ret = sh_pfc_map_add_config(&maps[idx], pin,
203					    PIN_MAP_TYPE_CONFIGS_PIN,
204					    configs, num_configs);
205		if (ret < 0)
206			goto done;
207
208		idx++;
209	}
210
211done:
212	*index = idx;
213	kfree(configs);
214	return ret;
215}
216
217static void sh_pfc_dt_free_map(struct pinctrl_dev *pctldev,
218			       struct pinctrl_map *map, unsigned num_maps)
219{
220	unsigned int i;
221
222	if (map == NULL)
223		return;
224
225	for (i = 0; i < num_maps; ++i) {
226		if (map[i].type == PIN_MAP_TYPE_CONFIGS_GROUP ||
227		    map[i].type == PIN_MAP_TYPE_CONFIGS_PIN)
228			kfree(map[i].data.configs.configs);
229	}
230
231	kfree(map);
232}
233
234static int sh_pfc_dt_node_to_map(struct pinctrl_dev *pctldev,
235				 struct device_node *np,
236				 struct pinctrl_map **map, unsigned *num_maps)
237{
238	struct sh_pfc_pinctrl *pmx = pinctrl_dev_get_drvdata(pctldev);
239	struct device *dev = pmx->pfc->dev;
240	struct device_node *child;
241	unsigned int index;
242	int ret;
243
244	*map = NULL;
245	*num_maps = 0;
246	index = 0;
247
248	for_each_child_of_node(np, child) {
249		ret = sh_pfc_dt_subnode_to_map(dev, child, map, num_maps,
250					       &index);
251		if (ret < 0)
252			goto done;
253	}
254
255	/* If no mapping has been found in child nodes try the config node. */
256	if (*num_maps == 0) {
257		ret = sh_pfc_dt_subnode_to_map(dev, np, map, num_maps, &index);
258		if (ret < 0)
259			goto done;
260	}
261
262	if (*num_maps)
263		return 0;
264
265	dev_err(dev, "no mapping found in node %s\n", np->full_name);
266	ret = -EINVAL;
267
268done:
269	if (ret < 0)
270		sh_pfc_dt_free_map(pctldev, *map, *num_maps);
271
272	return ret;
273}
274#endif /* CONFIG_OF */
275
276static const struct pinctrl_ops sh_pfc_pinctrl_ops = {
277	.get_groups_count	= sh_pfc_get_groups_count,
278	.get_group_name		= sh_pfc_get_group_name,
279	.get_group_pins		= sh_pfc_get_group_pins,
280	.pin_dbg_show		= sh_pfc_pin_dbg_show,
281#ifdef CONFIG_OF
282	.dt_node_to_map		= sh_pfc_dt_node_to_map,
283	.dt_free_map		= sh_pfc_dt_free_map,
284#endif
285};
286
287static int sh_pfc_get_functions_count(struct pinctrl_dev *pctldev)
288{
289	struct sh_pfc_pinctrl *pmx = pinctrl_dev_get_drvdata(pctldev);
290
291	return pmx->pfc->info->nr_functions;
292}
293
294static const char *sh_pfc_get_function_name(struct pinctrl_dev *pctldev,
295					    unsigned selector)
296{
297	struct sh_pfc_pinctrl *pmx = pinctrl_dev_get_drvdata(pctldev);
298
299	return pmx->pfc->info->functions[selector].name;
300}
301
302static int sh_pfc_get_function_groups(struct pinctrl_dev *pctldev,
303				      unsigned selector,
304				      const char * const **groups,
305				      unsigned * const num_groups)
306{
307	struct sh_pfc_pinctrl *pmx = pinctrl_dev_get_drvdata(pctldev);
308
309	*groups = pmx->pfc->info->functions[selector].groups;
310	*num_groups = pmx->pfc->info->functions[selector].nr_groups;
311
312	return 0;
313}
314
315static int sh_pfc_func_set_mux(struct pinctrl_dev *pctldev, unsigned selector,
316			       unsigned group)
317{
318	struct sh_pfc_pinctrl *pmx = pinctrl_dev_get_drvdata(pctldev);
319	struct sh_pfc *pfc = pmx->pfc;
320	const struct sh_pfc_pin_group *grp = &pfc->info->groups[group];
321	unsigned long flags;
322	unsigned int i;
323	int ret = 0;
324
325	spin_lock_irqsave(&pfc->lock, flags);
326
327	for (i = 0; i < grp->nr_pins; ++i) {
328		int idx = sh_pfc_get_pin_index(pfc, grp->pins[i]);
329		struct sh_pfc_pin_config *cfg = &pmx->configs[idx];
330
331		if (cfg->type != PINMUX_TYPE_NONE) {
332			ret = -EBUSY;
333			goto done;
334		}
335	}
336
337	for (i = 0; i < grp->nr_pins; ++i) {
338		ret = sh_pfc_config_mux(pfc, grp->mux[i], PINMUX_TYPE_FUNCTION);
339		if (ret < 0)
340			break;
341	}
342
343done:
344	spin_unlock_irqrestore(&pfc->lock, flags);
345	return ret;
346}
347
348static int sh_pfc_gpio_request_enable(struct pinctrl_dev *pctldev,
349				      struct pinctrl_gpio_range *range,
350				      unsigned offset)
351{
352	struct sh_pfc_pinctrl *pmx = pinctrl_dev_get_drvdata(pctldev);
353	struct sh_pfc *pfc = pmx->pfc;
354	int idx = sh_pfc_get_pin_index(pfc, offset);
355	struct sh_pfc_pin_config *cfg = &pmx->configs[idx];
356	unsigned long flags;
357	int ret;
358
359	spin_lock_irqsave(&pfc->lock, flags);
360
361	if (cfg->type != PINMUX_TYPE_NONE) {
362		dev_err(pfc->dev,
363			"Pin %u is busy, can't configure it as GPIO.\n",
364			offset);
365		ret = -EBUSY;
366		goto done;
367	}
368
369	if (!pfc->gpio) {
370		/* If GPIOs are handled externally the pin mux type need to be
371		 * set to GPIO here.
372		 */
373		const struct sh_pfc_pin *pin = &pfc->info->pins[idx];
374
375		ret = sh_pfc_config_mux(pfc, pin->enum_id, PINMUX_TYPE_GPIO);
376		if (ret < 0)
377			goto done;
378	}
379
380	cfg->type = PINMUX_TYPE_GPIO;
381
382	ret = 0;
383
384done:
385	spin_unlock_irqrestore(&pfc->lock, flags);
386
387	return ret;
388}
389
390static void sh_pfc_gpio_disable_free(struct pinctrl_dev *pctldev,
391				     struct pinctrl_gpio_range *range,
392				     unsigned offset)
393{
394	struct sh_pfc_pinctrl *pmx = pinctrl_dev_get_drvdata(pctldev);
395	struct sh_pfc *pfc = pmx->pfc;
396	int idx = sh_pfc_get_pin_index(pfc, offset);
397	struct sh_pfc_pin_config *cfg = &pmx->configs[idx];
398	unsigned long flags;
399
400	spin_lock_irqsave(&pfc->lock, flags);
401	cfg->type = PINMUX_TYPE_NONE;
402	spin_unlock_irqrestore(&pfc->lock, flags);
403}
404
405static int sh_pfc_gpio_set_direction(struct pinctrl_dev *pctldev,
406				     struct pinctrl_gpio_range *range,
407				     unsigned offset, bool input)
408{
409	struct sh_pfc_pinctrl *pmx = pinctrl_dev_get_drvdata(pctldev);
410	struct sh_pfc *pfc = pmx->pfc;
411	int new_type = input ? PINMUX_TYPE_INPUT : PINMUX_TYPE_OUTPUT;
412	int idx = sh_pfc_get_pin_index(pfc, offset);
413	const struct sh_pfc_pin *pin = &pfc->info->pins[idx];
414	struct sh_pfc_pin_config *cfg = &pmx->configs[idx];
415	unsigned long flags;
416	unsigned int dir;
417	int ret;
418
419	/* Check if the requested direction is supported by the pin. Not all SoC
420	 * provide pin config data, so perform the check conditionally.
421	 */
422	if (pin->configs) {
423		dir = input ? SH_PFC_PIN_CFG_INPUT : SH_PFC_PIN_CFG_OUTPUT;
424		if (!(pin->configs & dir))
425			return -EINVAL;
426	}
427
428	spin_lock_irqsave(&pfc->lock, flags);
429
430	ret = sh_pfc_config_mux(pfc, pin->enum_id, new_type);
431	if (ret < 0)
432		goto done;
433
434	cfg->type = new_type;
435
436done:
437	spin_unlock_irqrestore(&pfc->lock, flags);
438	return ret;
439}
440
441static const struct pinmux_ops sh_pfc_pinmux_ops = {
442	.get_functions_count	= sh_pfc_get_functions_count,
443	.get_function_name	= sh_pfc_get_function_name,
444	.get_function_groups	= sh_pfc_get_function_groups,
445	.set_mux		= sh_pfc_func_set_mux,
446	.gpio_request_enable	= sh_pfc_gpio_request_enable,
447	.gpio_disable_free	= sh_pfc_gpio_disable_free,
448	.gpio_set_direction	= sh_pfc_gpio_set_direction,
449};
450
451/* Check whether the requested parameter is supported for a pin. */
452static bool sh_pfc_pinconf_validate(struct sh_pfc *pfc, unsigned int _pin,
453				    enum pin_config_param param)
454{
455	int idx = sh_pfc_get_pin_index(pfc, _pin);
456	const struct sh_pfc_pin *pin = &pfc->info->pins[idx];
457
458	switch (param) {
459	case PIN_CONFIG_BIAS_DISABLE:
460		return true;
461
462	case PIN_CONFIG_BIAS_PULL_UP:
463		return pin->configs & SH_PFC_PIN_CFG_PULL_UP;
464
465	case PIN_CONFIG_BIAS_PULL_DOWN:
466		return pin->configs & SH_PFC_PIN_CFG_PULL_DOWN;
467
468	default:
469		return false;
470	}
471}
472
473static int sh_pfc_pinconf_get(struct pinctrl_dev *pctldev, unsigned _pin,
474			      unsigned long *config)
475{
476	struct sh_pfc_pinctrl *pmx = pinctrl_dev_get_drvdata(pctldev);
477	struct sh_pfc *pfc = pmx->pfc;
478	enum pin_config_param param = pinconf_to_config_param(*config);
479	unsigned long flags;
480	unsigned int bias;
481
482	if (!sh_pfc_pinconf_validate(pfc, _pin, param))
483		return -ENOTSUPP;
484
485	switch (param) {
486	case PIN_CONFIG_BIAS_DISABLE:
487	case PIN_CONFIG_BIAS_PULL_UP:
488	case PIN_CONFIG_BIAS_PULL_DOWN:
489		if (!pfc->info->ops || !pfc->info->ops->get_bias)
490			return -ENOTSUPP;
491
492		spin_lock_irqsave(&pfc->lock, flags);
493		bias = pfc->info->ops->get_bias(pfc, _pin);
494		spin_unlock_irqrestore(&pfc->lock, flags);
495
496		if (bias != param)
497			return -EINVAL;
498
499		*config = 0;
500		break;
501
502	default:
503		return -ENOTSUPP;
504	}
505
506	return 0;
507}
508
509static int sh_pfc_pinconf_set(struct pinctrl_dev *pctldev, unsigned _pin,
510			      unsigned long *configs, unsigned num_configs)
511{
512	struct sh_pfc_pinctrl *pmx = pinctrl_dev_get_drvdata(pctldev);
513	struct sh_pfc *pfc = pmx->pfc;
514	enum pin_config_param param;
515	unsigned long flags;
516	unsigned int i;
517
518	for (i = 0; i < num_configs; i++) {
519		param = pinconf_to_config_param(configs[i]);
520
521		if (!sh_pfc_pinconf_validate(pfc, _pin, param))
522			return -ENOTSUPP;
523
524		switch (param) {
525		case PIN_CONFIG_BIAS_PULL_UP:
526		case PIN_CONFIG_BIAS_PULL_DOWN:
527		case PIN_CONFIG_BIAS_DISABLE:
528			if (!pfc->info->ops || !pfc->info->ops->set_bias)
529				return -ENOTSUPP;
530
531			spin_lock_irqsave(&pfc->lock, flags);
532			pfc->info->ops->set_bias(pfc, _pin, param);
533			spin_unlock_irqrestore(&pfc->lock, flags);
534
535			break;
536
537		default:
538			return -ENOTSUPP;
539		}
540	} /* for each config */
541
542	return 0;
543}
544
545static int sh_pfc_pinconf_group_set(struct pinctrl_dev *pctldev, unsigned group,
546				    unsigned long *configs,
547				    unsigned num_configs)
548{
549	struct sh_pfc_pinctrl *pmx = pinctrl_dev_get_drvdata(pctldev);
550	const unsigned int *pins;
551	unsigned int num_pins;
552	unsigned int i;
553
554	pins = pmx->pfc->info->groups[group].pins;
555	num_pins = pmx->pfc->info->groups[group].nr_pins;
556
557	for (i = 0; i < num_pins; ++i)
558		sh_pfc_pinconf_set(pctldev, pins[i], configs, num_configs);
559
560	return 0;
561}
562
563static const struct pinconf_ops sh_pfc_pinconf_ops = {
564	.is_generic			= true,
565	.pin_config_get			= sh_pfc_pinconf_get,
566	.pin_config_set			= sh_pfc_pinconf_set,
567	.pin_config_group_set		= sh_pfc_pinconf_group_set,
568	.pin_config_config_dbg_show	= pinconf_generic_dump_config,
569};
570
571/* PFC ranges -> pinctrl pin descs */
572static int sh_pfc_map_pins(struct sh_pfc *pfc, struct sh_pfc_pinctrl *pmx)
573{
574	unsigned int i;
575
576	/* Allocate and initialize the pins and configs arrays. */
577	pmx->pins = devm_kzalloc(pfc->dev,
578				 sizeof(*pmx->pins) * pfc->info->nr_pins,
579				 GFP_KERNEL);
580	if (unlikely(!pmx->pins))
581		return -ENOMEM;
582
583	pmx->configs = devm_kzalloc(pfc->dev,
584				    sizeof(*pmx->configs) * pfc->info->nr_pins,
585				    GFP_KERNEL);
586	if (unlikely(!pmx->configs))
587		return -ENOMEM;
588
589	for (i = 0; i < pfc->info->nr_pins; ++i) {
590		const struct sh_pfc_pin *info = &pfc->info->pins[i];
591		struct sh_pfc_pin_config *cfg = &pmx->configs[i];
592		struct pinctrl_pin_desc *pin = &pmx->pins[i];
593
594		/* If the pin number is equal to -1 all pins are considered */
595		pin->number = info->pin != (u16)-1 ? info->pin : i;
596		pin->name = info->name;
597		cfg->type = PINMUX_TYPE_NONE;
598	}
599
600	return 0;
601}
602
603int sh_pfc_register_pinctrl(struct sh_pfc *pfc)
604{
605	struct sh_pfc_pinctrl *pmx;
606	int ret;
607
608	pmx = devm_kzalloc(pfc->dev, sizeof(*pmx), GFP_KERNEL);
609	if (unlikely(!pmx))
610		return -ENOMEM;
611
612	pmx->pfc = pfc;
613	pfc->pinctrl = pmx;
614
615	ret = sh_pfc_map_pins(pfc, pmx);
616	if (ret < 0)
617		return ret;
618
619	pmx->pctl_desc.name = DRV_NAME;
620	pmx->pctl_desc.owner = THIS_MODULE;
621	pmx->pctl_desc.pctlops = &sh_pfc_pinctrl_ops;
622	pmx->pctl_desc.pmxops = &sh_pfc_pinmux_ops;
623	pmx->pctl_desc.confops = &sh_pfc_pinconf_ops;
624	pmx->pctl_desc.pins = pmx->pins;
625	pmx->pctl_desc.npins = pfc->info->nr_pins;
626
627	pmx->pctl = pinctrl_register(&pmx->pctl_desc, pfc->dev, pmx);
628	if (pmx->pctl == NULL)
629		return -EINVAL;
630
631	return 0;
632}
633
634int sh_pfc_unregister_pinctrl(struct sh_pfc *pfc)
635{
636	struct sh_pfc_pinctrl *pmx = pfc->pinctrl;
637
638	pinctrl_unregister(pmx->pctl);
639
640	pfc->pinctrl = NULL;
641	return 0;
642}
643