1/*
2 * pin-controller/pin-mux/pin-config/gpio-driver for Samsung's SoC's.
3 *
4 * Copyright (c) 2012 Samsung Electronics Co., Ltd.
5 *		http://www.samsung.com
6 * Copyright (c) 2012 Linaro Ltd
7 *		http://www.linaro.org
8 *
9 * Author: Thomas Abraham <thomas.ab@samsung.com>
10 *
11 * This program is free software; you can redistribute it and/or modify
12 * it under the terms of the GNU General Public License as published by
13 * the Free Software Foundation; either version 2 of the License, or
14 * (at your option) any later version.
15 *
16 * This driver implements the Samsung pinctrl driver. It supports setting up of
17 * pinmux and pinconf configurations. The gpiolib interface is also included.
18 * External interrupt (gpio and wakeup) support are not included in this driver
19 * but provides extensions to which platform specific implementation of the gpio
20 * and wakeup interrupts can be hooked to.
21 */
22
23#include <linux/module.h>
24#include <linux/platform_device.h>
25#include <linux/io.h>
26#include <linux/slab.h>
27#include <linux/err.h>
28#include <linux/gpio.h>
29#include <linux/irqdomain.h>
30#include <linux/spinlock.h>
31#include <linux/syscore_ops.h>
32
33#include "../core.h"
34#include "pinctrl-samsung.h"
35
36#define GROUP_SUFFIX		"-grp"
37#define GSUFFIX_LEN		sizeof(GROUP_SUFFIX)
38#define FUNCTION_SUFFIX		"-mux"
39#define FSUFFIX_LEN		sizeof(FUNCTION_SUFFIX)
40
41/* list of all possible config options supported */
42static struct pin_config {
43	const char *property;
44	enum pincfg_type param;
45} cfg_params[] = {
46	{ "samsung,pin-pud", PINCFG_TYPE_PUD },
47	{ "samsung,pin-drv", PINCFG_TYPE_DRV },
48	{ "samsung,pin-con-pdn", PINCFG_TYPE_CON_PDN },
49	{ "samsung,pin-pud-pdn", PINCFG_TYPE_PUD_PDN },
50	{ "samsung,pin-val", PINCFG_TYPE_DAT },
51};
52
53/* Global list of devices (struct samsung_pinctrl_drv_data) */
54static LIST_HEAD(drvdata_list);
55
56static unsigned int pin_base;
57
58static inline struct samsung_pin_bank *gc_to_pin_bank(struct gpio_chip *gc)
59{
60	return container_of(gc, struct samsung_pin_bank, gpio_chip);
61}
62
63static int samsung_get_group_count(struct pinctrl_dev *pctldev)
64{
65	struct samsung_pinctrl_drv_data *pmx = pinctrl_dev_get_drvdata(pctldev);
66
67	return pmx->nr_groups;
68}
69
70static const char *samsung_get_group_name(struct pinctrl_dev *pctldev,
71						unsigned group)
72{
73	struct samsung_pinctrl_drv_data *pmx = pinctrl_dev_get_drvdata(pctldev);
74
75	return pmx->pin_groups[group].name;
76}
77
78static int samsung_get_group_pins(struct pinctrl_dev *pctldev,
79					unsigned group,
80					const unsigned **pins,
81					unsigned *num_pins)
82{
83	struct samsung_pinctrl_drv_data *pmx = pinctrl_dev_get_drvdata(pctldev);
84
85	*pins = pmx->pin_groups[group].pins;
86	*num_pins = pmx->pin_groups[group].num_pins;
87
88	return 0;
89}
90
91static int reserve_map(struct device *dev, struct pinctrl_map **map,
92		       unsigned *reserved_maps, unsigned *num_maps,
93		       unsigned reserve)
94{
95	unsigned old_num = *reserved_maps;
96	unsigned new_num = *num_maps + reserve;
97	struct pinctrl_map *new_map;
98
99	if (old_num >= new_num)
100		return 0;
101
102	new_map = krealloc(*map, sizeof(*new_map) * new_num, GFP_KERNEL);
103	if (!new_map) {
104		dev_err(dev, "krealloc(map) failed\n");
105		return -ENOMEM;
106	}
107
108	memset(new_map + old_num, 0, (new_num - old_num) * sizeof(*new_map));
109
110	*map = new_map;
111	*reserved_maps = new_num;
112
113	return 0;
114}
115
116static int add_map_mux(struct pinctrl_map **map, unsigned *reserved_maps,
117		       unsigned *num_maps, const char *group,
118		       const char *function)
119{
120	if (WARN_ON(*num_maps == *reserved_maps))
121		return -ENOSPC;
122
123	(*map)[*num_maps].type = PIN_MAP_TYPE_MUX_GROUP;
124	(*map)[*num_maps].data.mux.group = group;
125	(*map)[*num_maps].data.mux.function = function;
126	(*num_maps)++;
127
128	return 0;
129}
130
131static int add_map_configs(struct device *dev, struct pinctrl_map **map,
132			   unsigned *reserved_maps, unsigned *num_maps,
133			   const char *group, unsigned long *configs,
134			   unsigned num_configs)
135{
136	unsigned long *dup_configs;
137
138	if (WARN_ON(*num_maps == *reserved_maps))
139		return -ENOSPC;
140
141	dup_configs = kmemdup(configs, num_configs * sizeof(*dup_configs),
142			      GFP_KERNEL);
143	if (!dup_configs) {
144		dev_err(dev, "kmemdup(configs) failed\n");
145		return -ENOMEM;
146	}
147
148	(*map)[*num_maps].type = PIN_MAP_TYPE_CONFIGS_GROUP;
149	(*map)[*num_maps].data.configs.group_or_pin = group;
150	(*map)[*num_maps].data.configs.configs = dup_configs;
151	(*map)[*num_maps].data.configs.num_configs = num_configs;
152	(*num_maps)++;
153
154	return 0;
155}
156
157static int add_config(struct device *dev, unsigned long **configs,
158		      unsigned *num_configs, unsigned long config)
159{
160	unsigned old_num = *num_configs;
161	unsigned new_num = old_num + 1;
162	unsigned long *new_configs;
163
164	new_configs = krealloc(*configs, sizeof(*new_configs) * new_num,
165			       GFP_KERNEL);
166	if (!new_configs) {
167		dev_err(dev, "krealloc(configs) failed\n");
168		return -ENOMEM;
169	}
170
171	new_configs[old_num] = config;
172
173	*configs = new_configs;
174	*num_configs = new_num;
175
176	return 0;
177}
178
179static void samsung_dt_free_map(struct pinctrl_dev *pctldev,
180				      struct pinctrl_map *map,
181				      unsigned num_maps)
182{
183	int i;
184
185	for (i = 0; i < num_maps; i++)
186		if (map[i].type == PIN_MAP_TYPE_CONFIGS_GROUP)
187			kfree(map[i].data.configs.configs);
188
189	kfree(map);
190}
191
192static int samsung_dt_subnode_to_map(struct samsung_pinctrl_drv_data *drvdata,
193				     struct device *dev,
194				     struct device_node *np,
195				     struct pinctrl_map **map,
196				     unsigned *reserved_maps,
197				     unsigned *num_maps)
198{
199	int ret, i;
200	u32 val;
201	unsigned long config;
202	unsigned long *configs = NULL;
203	unsigned num_configs = 0;
204	unsigned reserve;
205	struct property *prop;
206	const char *group;
207	bool has_func = false;
208
209	ret = of_property_read_u32(np, "samsung,pin-function", &val);
210	if (!ret)
211		has_func = true;
212
213	for (i = 0; i < ARRAY_SIZE(cfg_params); i++) {
214		ret = of_property_read_u32(np, cfg_params[i].property, &val);
215		if (!ret) {
216			config = PINCFG_PACK(cfg_params[i].param, val);
217			ret = add_config(dev, &configs, &num_configs, config);
218			if (ret < 0)
219				goto exit;
220		/* EINVAL=missing, which is fine since it's optional */
221		} else if (ret != -EINVAL) {
222			dev_err(dev, "could not parse property %s\n",
223				cfg_params[i].property);
224		}
225	}
226
227	reserve = 0;
228	if (has_func)
229		reserve++;
230	if (num_configs)
231		reserve++;
232	ret = of_property_count_strings(np, "samsung,pins");
233	if (ret < 0) {
234		dev_err(dev, "could not parse property samsung,pins\n");
235		goto exit;
236	}
237	reserve *= ret;
238
239	ret = reserve_map(dev, map, reserved_maps, num_maps, reserve);
240	if (ret < 0)
241		goto exit;
242
243	of_property_for_each_string(np, "samsung,pins", prop, group) {
244		if (has_func) {
245			ret = add_map_mux(map, reserved_maps,
246						num_maps, group, np->full_name);
247			if (ret < 0)
248				goto exit;
249		}
250
251		if (num_configs) {
252			ret = add_map_configs(dev, map, reserved_maps,
253					      num_maps, group, configs,
254					      num_configs);
255			if (ret < 0)
256				goto exit;
257		}
258	}
259
260	ret = 0;
261
262exit:
263	kfree(configs);
264	return ret;
265}
266
267static int samsung_dt_node_to_map(struct pinctrl_dev *pctldev,
268					struct device_node *np_config,
269					struct pinctrl_map **map,
270					unsigned *num_maps)
271{
272	struct samsung_pinctrl_drv_data *drvdata;
273	unsigned reserved_maps;
274	struct device_node *np;
275	int ret;
276
277	drvdata = pinctrl_dev_get_drvdata(pctldev);
278
279	reserved_maps = 0;
280	*map = NULL;
281	*num_maps = 0;
282
283	if (!of_get_child_count(np_config))
284		return samsung_dt_subnode_to_map(drvdata, pctldev->dev,
285							np_config, map,
286							&reserved_maps,
287							num_maps);
288
289	for_each_child_of_node(np_config, np) {
290		ret = samsung_dt_subnode_to_map(drvdata, pctldev->dev, np, map,
291						&reserved_maps, num_maps);
292		if (ret < 0) {
293			samsung_dt_free_map(pctldev, *map, *num_maps);
294			return ret;
295		}
296	}
297
298	return 0;
299}
300
301/* list of pinctrl callbacks for the pinctrl core */
302static const struct pinctrl_ops samsung_pctrl_ops = {
303	.get_groups_count	= samsung_get_group_count,
304	.get_group_name		= samsung_get_group_name,
305	.get_group_pins		= samsung_get_group_pins,
306	.dt_node_to_map		= samsung_dt_node_to_map,
307	.dt_free_map		= samsung_dt_free_map,
308};
309
310/* check if the selector is a valid pin function selector */
311static int samsung_get_functions_count(struct pinctrl_dev *pctldev)
312{
313	struct samsung_pinctrl_drv_data *drvdata;
314
315	drvdata = pinctrl_dev_get_drvdata(pctldev);
316	return drvdata->nr_functions;
317}
318
319/* return the name of the pin function specified */
320static const char *samsung_pinmux_get_fname(struct pinctrl_dev *pctldev,
321						unsigned selector)
322{
323	struct samsung_pinctrl_drv_data *drvdata;
324
325	drvdata = pinctrl_dev_get_drvdata(pctldev);
326	return drvdata->pmx_functions[selector].name;
327}
328
329/* return the groups associated for the specified function selector */
330static int samsung_pinmux_get_groups(struct pinctrl_dev *pctldev,
331		unsigned selector, const char * const **groups,
332		unsigned * const num_groups)
333{
334	struct samsung_pinctrl_drv_data *drvdata;
335
336	drvdata = pinctrl_dev_get_drvdata(pctldev);
337	*groups = drvdata->pmx_functions[selector].groups;
338	*num_groups = drvdata->pmx_functions[selector].num_groups;
339	return 0;
340}
341
342/*
343 * given a pin number that is local to a pin controller, find out the pin bank
344 * and the register base of the pin bank.
345 */
346static void pin_to_reg_bank(struct samsung_pinctrl_drv_data *drvdata,
347			unsigned pin, void __iomem **reg, u32 *offset,
348			struct samsung_pin_bank **bank)
349{
350	struct samsung_pin_bank *b;
351
352	b = drvdata->pin_banks;
353
354	while ((pin >= b->pin_base) &&
355			((b->pin_base + b->nr_pins - 1) < pin))
356		b++;
357
358	*reg = drvdata->virt_base + b->pctl_offset;
359	*offset = pin - b->pin_base;
360	if (bank)
361		*bank = b;
362}
363
364/* enable or disable a pinmux function */
365static void samsung_pinmux_setup(struct pinctrl_dev *pctldev, unsigned selector,
366					unsigned group, bool enable)
367{
368	struct samsung_pinctrl_drv_data *drvdata;
369	const struct samsung_pin_bank_type *type;
370	struct samsung_pin_bank *bank;
371	void __iomem *reg;
372	u32 mask, shift, data, pin_offset;
373	unsigned long flags;
374	const struct samsung_pmx_func *func;
375	const struct samsung_pin_group *grp;
376
377	drvdata = pinctrl_dev_get_drvdata(pctldev);
378	func = &drvdata->pmx_functions[selector];
379	grp = &drvdata->pin_groups[group];
380
381	pin_to_reg_bank(drvdata, grp->pins[0] - drvdata->pin_base,
382			&reg, &pin_offset, &bank);
383	type = bank->type;
384	mask = (1 << type->fld_width[PINCFG_TYPE_FUNC]) - 1;
385	shift = pin_offset * type->fld_width[PINCFG_TYPE_FUNC];
386	if (shift >= 32) {
387		/* Some banks have two config registers */
388		shift -= 32;
389		reg += 4;
390	}
391
392	spin_lock_irqsave(&bank->slock, flags);
393
394	data = readl(reg + type->reg_offset[PINCFG_TYPE_FUNC]);
395	data &= ~(mask << shift);
396	if (enable)
397		data |= func->val << shift;
398	writel(data, reg + type->reg_offset[PINCFG_TYPE_FUNC]);
399
400	spin_unlock_irqrestore(&bank->slock, flags);
401}
402
403/* enable a specified pinmux by writing to registers */
404static int samsung_pinmux_set_mux(struct pinctrl_dev *pctldev,
405				  unsigned selector,
406				  unsigned group)
407{
408	samsung_pinmux_setup(pctldev, selector, group, true);
409	return 0;
410}
411
412/* list of pinmux callbacks for the pinmux vertical in pinctrl core */
413static const struct pinmux_ops samsung_pinmux_ops = {
414	.get_functions_count	= samsung_get_functions_count,
415	.get_function_name	= samsung_pinmux_get_fname,
416	.get_function_groups	= samsung_pinmux_get_groups,
417	.set_mux		= samsung_pinmux_set_mux,
418};
419
420/* set or get the pin config settings for a specified pin */
421static int samsung_pinconf_rw(struct pinctrl_dev *pctldev, unsigned int pin,
422				unsigned long *config, bool set)
423{
424	struct samsung_pinctrl_drv_data *drvdata;
425	const struct samsung_pin_bank_type *type;
426	struct samsung_pin_bank *bank;
427	void __iomem *reg_base;
428	enum pincfg_type cfg_type = PINCFG_UNPACK_TYPE(*config);
429	u32 data, width, pin_offset, mask, shift;
430	u32 cfg_value, cfg_reg;
431	unsigned long flags;
432
433	drvdata = pinctrl_dev_get_drvdata(pctldev);
434	pin_to_reg_bank(drvdata, pin - drvdata->pin_base, &reg_base,
435					&pin_offset, &bank);
436	type = bank->type;
437
438	if (cfg_type >= PINCFG_TYPE_NUM || !type->fld_width[cfg_type])
439		return -EINVAL;
440
441	width = type->fld_width[cfg_type];
442	cfg_reg = type->reg_offset[cfg_type];
443
444	spin_lock_irqsave(&bank->slock, flags);
445
446	mask = (1 << width) - 1;
447	shift = pin_offset * width;
448	data = readl(reg_base + cfg_reg);
449
450	if (set) {
451		cfg_value = PINCFG_UNPACK_VALUE(*config);
452		data &= ~(mask << shift);
453		data |= (cfg_value << shift);
454		writel(data, reg_base + cfg_reg);
455	} else {
456		data >>= shift;
457		data &= mask;
458		*config = PINCFG_PACK(cfg_type, data);
459	}
460
461	spin_unlock_irqrestore(&bank->slock, flags);
462
463	return 0;
464}
465
466/* set the pin config settings for a specified pin */
467static int samsung_pinconf_set(struct pinctrl_dev *pctldev, unsigned int pin,
468				unsigned long *configs, unsigned num_configs)
469{
470	int i, ret;
471
472	for (i = 0; i < num_configs; i++) {
473		ret = samsung_pinconf_rw(pctldev, pin, &configs[i], true);
474		if (ret < 0)
475			return ret;
476	} /* for each config */
477
478	return 0;
479}
480
481/* get the pin config settings for a specified pin */
482static int samsung_pinconf_get(struct pinctrl_dev *pctldev, unsigned int pin,
483					unsigned long *config)
484{
485	return samsung_pinconf_rw(pctldev, pin, config, false);
486}
487
488/* set the pin config settings for a specified pin group */
489static int samsung_pinconf_group_set(struct pinctrl_dev *pctldev,
490			unsigned group, unsigned long *configs,
491			unsigned num_configs)
492{
493	struct samsung_pinctrl_drv_data *drvdata;
494	const unsigned int *pins;
495	unsigned int cnt;
496
497	drvdata = pinctrl_dev_get_drvdata(pctldev);
498	pins = drvdata->pin_groups[group].pins;
499
500	for (cnt = 0; cnt < drvdata->pin_groups[group].num_pins; cnt++)
501		samsung_pinconf_set(pctldev, pins[cnt], configs, num_configs);
502
503	return 0;
504}
505
506/* get the pin config settings for a specified pin group */
507static int samsung_pinconf_group_get(struct pinctrl_dev *pctldev,
508				unsigned int group, unsigned long *config)
509{
510	struct samsung_pinctrl_drv_data *drvdata;
511	const unsigned int *pins;
512
513	drvdata = pinctrl_dev_get_drvdata(pctldev);
514	pins = drvdata->pin_groups[group].pins;
515	samsung_pinconf_get(pctldev, pins[0], config);
516	return 0;
517}
518
519/* list of pinconfig callbacks for pinconfig vertical in the pinctrl code */
520static const struct pinconf_ops samsung_pinconf_ops = {
521	.pin_config_get		= samsung_pinconf_get,
522	.pin_config_set		= samsung_pinconf_set,
523	.pin_config_group_get	= samsung_pinconf_group_get,
524	.pin_config_group_set	= samsung_pinconf_group_set,
525};
526
527/* gpiolib gpio_set callback function */
528static void samsung_gpio_set(struct gpio_chip *gc, unsigned offset, int value)
529{
530	struct samsung_pin_bank *bank = gc_to_pin_bank(gc);
531	const struct samsung_pin_bank_type *type = bank->type;
532	unsigned long flags;
533	void __iomem *reg;
534	u32 data;
535
536	reg = bank->drvdata->virt_base + bank->pctl_offset;
537
538	spin_lock_irqsave(&bank->slock, flags);
539
540	data = readl(reg + type->reg_offset[PINCFG_TYPE_DAT]);
541	data &= ~(1 << offset);
542	if (value)
543		data |= 1 << offset;
544	writel(data, reg + type->reg_offset[PINCFG_TYPE_DAT]);
545
546	spin_unlock_irqrestore(&bank->slock, flags);
547}
548
549/* gpiolib gpio_get callback function */
550static int samsung_gpio_get(struct gpio_chip *gc, unsigned offset)
551{
552	void __iomem *reg;
553	u32 data;
554	struct samsung_pin_bank *bank = gc_to_pin_bank(gc);
555	const struct samsung_pin_bank_type *type = bank->type;
556
557	reg = bank->drvdata->virt_base + bank->pctl_offset;
558
559	data = readl(reg + type->reg_offset[PINCFG_TYPE_DAT]);
560	data >>= offset;
561	data &= 1;
562	return data;
563}
564
565/*
566 * The calls to gpio_direction_output() and gpio_direction_input()
567 * leads to this function call.
568 */
569static int samsung_gpio_set_direction(struct gpio_chip *gc,
570					     unsigned offset, bool input)
571{
572	const struct samsung_pin_bank_type *type;
573	struct samsung_pin_bank *bank;
574	struct samsung_pinctrl_drv_data *drvdata;
575	void __iomem *reg;
576	u32 data, mask, shift;
577	unsigned long flags;
578
579	bank = gc_to_pin_bank(gc);
580	type = bank->type;
581	drvdata = bank->drvdata;
582
583	reg = drvdata->virt_base + bank->pctl_offset +
584					type->reg_offset[PINCFG_TYPE_FUNC];
585
586	mask = (1 << type->fld_width[PINCFG_TYPE_FUNC]) - 1;
587	shift = offset * type->fld_width[PINCFG_TYPE_FUNC];
588	if (shift >= 32) {
589		/* Some banks have two config registers */
590		shift -= 32;
591		reg += 4;
592	}
593
594	spin_lock_irqsave(&bank->slock, flags);
595
596	data = readl(reg);
597	data &= ~(mask << shift);
598	if (!input)
599		data |= FUNC_OUTPUT << shift;
600	writel(data, reg);
601
602	spin_unlock_irqrestore(&bank->slock, flags);
603
604	return 0;
605}
606
607/* gpiolib gpio_direction_input callback function. */
608static int samsung_gpio_direction_input(struct gpio_chip *gc, unsigned offset)
609{
610	return samsung_gpio_set_direction(gc, offset, true);
611}
612
613/* gpiolib gpio_direction_output callback function. */
614static int samsung_gpio_direction_output(struct gpio_chip *gc, unsigned offset,
615							int value)
616{
617	samsung_gpio_set(gc, offset, value);
618	return samsung_gpio_set_direction(gc, offset, false);
619}
620
621/*
622 * gpiolib gpio_to_irq callback function. Creates a mapping between a GPIO pin
623 * and a virtual IRQ, if not already present.
624 */
625static int samsung_gpio_to_irq(struct gpio_chip *gc, unsigned offset)
626{
627	struct samsung_pin_bank *bank = gc_to_pin_bank(gc);
628	unsigned int virq;
629
630	if (!bank->irq_domain)
631		return -ENXIO;
632
633	virq = irq_create_mapping(bank->irq_domain, offset);
634
635	return (virq) ? : -ENXIO;
636}
637
638static struct samsung_pin_group *samsung_pinctrl_create_groups(
639				struct device *dev,
640				struct samsung_pinctrl_drv_data *drvdata,
641				unsigned int *cnt)
642{
643	struct pinctrl_desc *ctrldesc = &drvdata->pctl;
644	struct samsung_pin_group *groups, *grp;
645	const struct pinctrl_pin_desc *pdesc;
646	int i;
647
648	groups = devm_kzalloc(dev, ctrldesc->npins * sizeof(*groups),
649				GFP_KERNEL);
650	if (!groups)
651		return ERR_PTR(-EINVAL);
652	grp = groups;
653
654	pdesc = ctrldesc->pins;
655	for (i = 0; i < ctrldesc->npins; ++i, ++pdesc, ++grp) {
656		grp->name = pdesc->name;
657		grp->pins = &pdesc->number;
658		grp->num_pins = 1;
659	}
660
661	*cnt = ctrldesc->npins;
662	return groups;
663}
664
665static int samsung_pinctrl_create_function(struct device *dev,
666				struct samsung_pinctrl_drv_data *drvdata,
667				struct device_node *func_np,
668				struct samsung_pmx_func *func)
669{
670	int npins;
671	int ret;
672	int i;
673
674	if (of_property_read_u32(func_np, "samsung,pin-function", &func->val))
675		return 0;
676
677	npins = of_property_count_strings(func_np, "samsung,pins");
678	if (npins < 1) {
679		dev_err(dev, "invalid pin list in %s node", func_np->name);
680		return -EINVAL;
681	}
682
683	func->name = func_np->full_name;
684
685	func->groups = devm_kzalloc(dev, npins * sizeof(char *), GFP_KERNEL);
686	if (!func->groups)
687		return -ENOMEM;
688
689	for (i = 0; i < npins; ++i) {
690		const char *gname;
691
692		ret = of_property_read_string_index(func_np, "samsung,pins",
693							i, &gname);
694		if (ret) {
695			dev_err(dev,
696				"failed to read pin name %d from %s node\n",
697				i, func_np->name);
698			return ret;
699		}
700
701		func->groups[i] = gname;
702	}
703
704	func->num_groups = npins;
705	return 1;
706}
707
708static struct samsung_pmx_func *samsung_pinctrl_create_functions(
709				struct device *dev,
710				struct samsung_pinctrl_drv_data *drvdata,
711				unsigned int *cnt)
712{
713	struct samsung_pmx_func *functions, *func;
714	struct device_node *dev_np = dev->of_node;
715	struct device_node *cfg_np;
716	unsigned int func_cnt = 0;
717	int ret;
718
719	/*
720	 * Iterate over all the child nodes of the pin controller node
721	 * and create pin groups and pin function lists.
722	 */
723	for_each_child_of_node(dev_np, cfg_np) {
724		struct device_node *func_np;
725
726		if (!of_get_child_count(cfg_np)) {
727			if (!of_find_property(cfg_np,
728			    "samsung,pin-function", NULL))
729				continue;
730			++func_cnt;
731			continue;
732		}
733
734		for_each_child_of_node(cfg_np, func_np) {
735			if (!of_find_property(func_np,
736			    "samsung,pin-function", NULL))
737				continue;
738			++func_cnt;
739		}
740	}
741
742	functions = devm_kzalloc(dev, func_cnt * sizeof(*functions),
743					GFP_KERNEL);
744	if (!functions) {
745		dev_err(dev, "failed to allocate memory for function list\n");
746		return ERR_PTR(-EINVAL);
747	}
748	func = functions;
749
750	/*
751	 * Iterate over all the child nodes of the pin controller node
752	 * and create pin groups and pin function lists.
753	 */
754	func_cnt = 0;
755	for_each_child_of_node(dev_np, cfg_np) {
756		struct device_node *func_np;
757
758		if (!of_get_child_count(cfg_np)) {
759			ret = samsung_pinctrl_create_function(dev, drvdata,
760							cfg_np, func);
761			if (ret < 0)
762				return ERR_PTR(ret);
763			if (ret > 0) {
764				++func;
765				++func_cnt;
766			}
767			continue;
768		}
769
770		for_each_child_of_node(cfg_np, func_np) {
771			ret = samsung_pinctrl_create_function(dev, drvdata,
772						func_np, func);
773			if (ret < 0)
774				return ERR_PTR(ret);
775			if (ret > 0) {
776				++func;
777				++func_cnt;
778			}
779		}
780	}
781
782	*cnt = func_cnt;
783	return functions;
784}
785
786/*
787 * Parse the information about all the available pin groups and pin functions
788 * from device node of the pin-controller. A pin group is formed with all
789 * the pins listed in the "samsung,pins" property.
790 */
791
792static int samsung_pinctrl_parse_dt(struct platform_device *pdev,
793				    struct samsung_pinctrl_drv_data *drvdata)
794{
795	struct device *dev = &pdev->dev;
796	struct samsung_pin_group *groups;
797	struct samsung_pmx_func *functions;
798	unsigned int grp_cnt = 0, func_cnt = 0;
799
800	groups = samsung_pinctrl_create_groups(dev, drvdata, &grp_cnt);
801	if (IS_ERR(groups)) {
802		dev_err(dev, "failed to parse pin groups\n");
803		return PTR_ERR(groups);
804	}
805
806	functions = samsung_pinctrl_create_functions(dev, drvdata, &func_cnt);
807	if (IS_ERR(functions)) {
808		dev_err(dev, "failed to parse pin functions\n");
809		return PTR_ERR(groups);
810	}
811
812	drvdata->pin_groups = groups;
813	drvdata->nr_groups = grp_cnt;
814	drvdata->pmx_functions = functions;
815	drvdata->nr_functions = func_cnt;
816
817	return 0;
818}
819
820/* register the pinctrl interface with the pinctrl subsystem */
821static int samsung_pinctrl_register(struct platform_device *pdev,
822				    struct samsung_pinctrl_drv_data *drvdata)
823{
824	struct pinctrl_desc *ctrldesc = &drvdata->pctl;
825	struct pinctrl_pin_desc *pindesc, *pdesc;
826	struct samsung_pin_bank *pin_bank;
827	char *pin_names;
828	int pin, bank, ret;
829
830	ctrldesc->name = "samsung-pinctrl";
831	ctrldesc->owner = THIS_MODULE;
832	ctrldesc->pctlops = &samsung_pctrl_ops;
833	ctrldesc->pmxops = &samsung_pinmux_ops;
834	ctrldesc->confops = &samsung_pinconf_ops;
835
836	pindesc = devm_kzalloc(&pdev->dev, sizeof(*pindesc) *
837			drvdata->nr_pins, GFP_KERNEL);
838	if (!pindesc) {
839		dev_err(&pdev->dev, "mem alloc for pin descriptors failed\n");
840		return -ENOMEM;
841	}
842	ctrldesc->pins = pindesc;
843	ctrldesc->npins = drvdata->nr_pins;
844
845	/* dynamically populate the pin number and pin name for pindesc */
846	for (pin = 0, pdesc = pindesc; pin < ctrldesc->npins; pin++, pdesc++)
847		pdesc->number = pin + drvdata->pin_base;
848
849	/*
850	 * allocate space for storing the dynamically generated names for all
851	 * the pins which belong to this pin-controller.
852	 */
853	pin_names = devm_kzalloc(&pdev->dev, sizeof(char) * PIN_NAME_LENGTH *
854					drvdata->nr_pins, GFP_KERNEL);
855	if (!pin_names) {
856		dev_err(&pdev->dev, "mem alloc for pin names failed\n");
857		return -ENOMEM;
858	}
859
860	/* for each pin, the name of the pin is pin-bank name + pin number */
861	for (bank = 0; bank < drvdata->nr_banks; bank++) {
862		pin_bank = &drvdata->pin_banks[bank];
863		for (pin = 0; pin < pin_bank->nr_pins; pin++) {
864			sprintf(pin_names, "%s-%d", pin_bank->name, pin);
865			pdesc = pindesc + pin_bank->pin_base + pin;
866			pdesc->name = pin_names;
867			pin_names += PIN_NAME_LENGTH;
868		}
869	}
870
871	ret = samsung_pinctrl_parse_dt(pdev, drvdata);
872	if (ret)
873		return ret;
874
875	drvdata->pctl_dev = pinctrl_register(ctrldesc, &pdev->dev, drvdata);
876	if (!drvdata->pctl_dev) {
877		dev_err(&pdev->dev, "could not register pinctrl driver\n");
878		return -EINVAL;
879	}
880
881	for (bank = 0; bank < drvdata->nr_banks; ++bank) {
882		pin_bank = &drvdata->pin_banks[bank];
883		pin_bank->grange.name = pin_bank->name;
884		pin_bank->grange.id = bank;
885		pin_bank->grange.pin_base = drvdata->pin_base
886						+ pin_bank->pin_base;
887		pin_bank->grange.base = pin_bank->gpio_chip.base;
888		pin_bank->grange.npins = pin_bank->gpio_chip.ngpio;
889		pin_bank->grange.gc = &pin_bank->gpio_chip;
890		pinctrl_add_gpio_range(drvdata->pctl_dev, &pin_bank->grange);
891	}
892
893	return 0;
894}
895
896static int samsung_gpio_request(struct gpio_chip *chip, unsigned offset)
897{
898	return pinctrl_request_gpio(chip->base + offset);
899}
900
901static void samsung_gpio_free(struct gpio_chip *chip, unsigned offset)
902{
903	pinctrl_free_gpio(chip->base + offset);
904}
905
906static const struct gpio_chip samsung_gpiolib_chip = {
907	.request = samsung_gpio_request,
908	.free = samsung_gpio_free,
909	.set = samsung_gpio_set,
910	.get = samsung_gpio_get,
911	.direction_input = samsung_gpio_direction_input,
912	.direction_output = samsung_gpio_direction_output,
913	.to_irq = samsung_gpio_to_irq,
914	.owner = THIS_MODULE,
915};
916
917/* register the gpiolib interface with the gpiolib subsystem */
918static int samsung_gpiolib_register(struct platform_device *pdev,
919				    struct samsung_pinctrl_drv_data *drvdata)
920{
921	struct samsung_pin_bank *bank = drvdata->pin_banks;
922	struct gpio_chip *gc;
923	int ret;
924	int i;
925
926	for (i = 0; i < drvdata->nr_banks; ++i, ++bank) {
927		bank->gpio_chip = samsung_gpiolib_chip;
928
929		gc = &bank->gpio_chip;
930		gc->base = drvdata->pin_base + bank->pin_base;
931		gc->ngpio = bank->nr_pins;
932		gc->dev = &pdev->dev;
933		gc->of_node = bank->of_node;
934		gc->label = bank->name;
935
936		ret = gpiochip_add(gc);
937		if (ret) {
938			dev_err(&pdev->dev, "failed to register gpio_chip %s, error code: %d\n",
939							gc->label, ret);
940			goto fail;
941		}
942	}
943
944	return 0;
945
946fail:
947	for (--i, --bank; i >= 0; --i, --bank)
948		gpiochip_remove(&bank->gpio_chip);
949	return ret;
950}
951
952/* unregister the gpiolib interface with the gpiolib subsystem */
953static int samsung_gpiolib_unregister(struct platform_device *pdev,
954				      struct samsung_pinctrl_drv_data *drvdata)
955{
956	struct samsung_pin_bank *bank = drvdata->pin_banks;
957	int i;
958
959	for (i = 0; i < drvdata->nr_banks; ++i, ++bank)
960		gpiochip_remove(&bank->gpio_chip);
961
962	return 0;
963}
964
965static const struct of_device_id samsung_pinctrl_dt_match[];
966
967/* retrieve the soc specific data */
968static const struct samsung_pin_ctrl *
969samsung_pinctrl_get_soc_data(struct samsung_pinctrl_drv_data *d,
970			     struct platform_device *pdev)
971{
972	int id;
973	const struct of_device_id *match;
974	struct device_node *node = pdev->dev.of_node;
975	struct device_node *np;
976	const struct samsung_pin_bank_data *bdata;
977	const struct samsung_pin_ctrl *ctrl;
978	struct samsung_pin_bank *bank;
979	int i;
980
981	id = of_alias_get_id(node, "pinctrl");
982	if (id < 0) {
983		dev_err(&pdev->dev, "failed to get alias id\n");
984		return ERR_PTR(-ENOENT);
985	}
986	match = of_match_node(samsung_pinctrl_dt_match, node);
987	ctrl = (struct samsung_pin_ctrl *)match->data + id;
988
989	d->suspend = ctrl->suspend;
990	d->resume = ctrl->resume;
991	d->nr_banks = ctrl->nr_banks;
992	d->pin_banks = devm_kcalloc(&pdev->dev, d->nr_banks,
993					sizeof(*d->pin_banks), GFP_KERNEL);
994	if (!d->pin_banks)
995		return ERR_PTR(-ENOMEM);
996
997	bank = d->pin_banks;
998	bdata = ctrl->pin_banks;
999	for (i = 0; i < ctrl->nr_banks; ++i, ++bdata, ++bank) {
1000		bank->type = bdata->type;
1001		bank->pctl_offset = bdata->pctl_offset;
1002		bank->nr_pins = bdata->nr_pins;
1003		bank->eint_func = bdata->eint_func;
1004		bank->eint_type = bdata->eint_type;
1005		bank->eint_mask = bdata->eint_mask;
1006		bank->eint_offset = bdata->eint_offset;
1007		bank->name = bdata->name;
1008
1009		spin_lock_init(&bank->slock);
1010		bank->drvdata = d;
1011		bank->pin_base = d->nr_pins;
1012		d->nr_pins += bank->nr_pins;
1013	}
1014
1015	for_each_child_of_node(node, np) {
1016		if (!of_find_property(np, "gpio-controller", NULL))
1017			continue;
1018		bank = d->pin_banks;
1019		for (i = 0; i < d->nr_banks; ++i, ++bank) {
1020			if (!strcmp(bank->name, np->name)) {
1021				bank->of_node = np;
1022				break;
1023			}
1024		}
1025	}
1026
1027	d->pin_base = pin_base;
1028	pin_base += d->nr_pins;
1029
1030	return ctrl;
1031}
1032
1033static int samsung_pinctrl_probe(struct platform_device *pdev)
1034{
1035	struct samsung_pinctrl_drv_data *drvdata;
1036	const struct samsung_pin_ctrl *ctrl;
1037	struct device *dev = &pdev->dev;
1038	struct resource *res;
1039	int ret;
1040
1041	if (!dev->of_node) {
1042		dev_err(dev, "device tree node not found\n");
1043		return -ENODEV;
1044	}
1045
1046	drvdata = devm_kzalloc(dev, sizeof(*drvdata), GFP_KERNEL);
1047	if (!drvdata) {
1048		dev_err(dev, "failed to allocate memory for driver's "
1049				"private data\n");
1050		return -ENOMEM;
1051	}
1052
1053	ctrl = samsung_pinctrl_get_soc_data(drvdata, pdev);
1054	if (IS_ERR(ctrl)) {
1055		dev_err(&pdev->dev, "driver data not available\n");
1056		return PTR_ERR(ctrl);
1057	}
1058	drvdata->dev = dev;
1059
1060	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1061	drvdata->virt_base = devm_ioremap_resource(&pdev->dev, res);
1062	if (IS_ERR(drvdata->virt_base))
1063		return PTR_ERR(drvdata->virt_base);
1064
1065	res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
1066	if (res)
1067		drvdata->irq = res->start;
1068
1069	ret = samsung_gpiolib_register(pdev, drvdata);
1070	if (ret)
1071		return ret;
1072
1073	ret = samsung_pinctrl_register(pdev, drvdata);
1074	if (ret) {
1075		samsung_gpiolib_unregister(pdev, drvdata);
1076		return ret;
1077	}
1078
1079	if (ctrl->eint_gpio_init)
1080		ctrl->eint_gpio_init(drvdata);
1081	if (ctrl->eint_wkup_init)
1082		ctrl->eint_wkup_init(drvdata);
1083
1084	platform_set_drvdata(pdev, drvdata);
1085
1086	/* Add to the global list */
1087	list_add_tail(&drvdata->node, &drvdata_list);
1088
1089	return 0;
1090}
1091
1092#ifdef CONFIG_PM
1093
1094/**
1095 * samsung_pinctrl_suspend_dev - save pinctrl state for suspend for a device
1096 *
1097 * Save data for all banks handled by this device.
1098 */
1099static void samsung_pinctrl_suspend_dev(
1100	struct samsung_pinctrl_drv_data *drvdata)
1101{
1102	void __iomem *virt_base = drvdata->virt_base;
1103	int i;
1104
1105	for (i = 0; i < drvdata->nr_banks; i++) {
1106		struct samsung_pin_bank *bank = &drvdata->pin_banks[i];
1107		void __iomem *reg = virt_base + bank->pctl_offset;
1108		const u8 *offs = bank->type->reg_offset;
1109		const u8 *widths = bank->type->fld_width;
1110		enum pincfg_type type;
1111
1112		/* Registers without a powerdown config aren't lost */
1113		if (!widths[PINCFG_TYPE_CON_PDN])
1114			continue;
1115
1116		for (type = 0; type < PINCFG_TYPE_NUM; type++)
1117			if (widths[type])
1118				bank->pm_save[type] = readl(reg + offs[type]);
1119
1120		if (widths[PINCFG_TYPE_FUNC] * bank->nr_pins > 32) {
1121			/* Some banks have two config registers */
1122			bank->pm_save[PINCFG_TYPE_NUM] =
1123				readl(reg + offs[PINCFG_TYPE_FUNC] + 4);
1124			pr_debug("Save %s @ %p (con %#010x %08x)\n",
1125				 bank->name, reg,
1126				 bank->pm_save[PINCFG_TYPE_FUNC],
1127				 bank->pm_save[PINCFG_TYPE_NUM]);
1128		} else {
1129			pr_debug("Save %s @ %p (con %#010x)\n", bank->name,
1130				 reg, bank->pm_save[PINCFG_TYPE_FUNC]);
1131		}
1132	}
1133
1134	if (drvdata->suspend)
1135		drvdata->suspend(drvdata);
1136}
1137
1138/**
1139 * samsung_pinctrl_resume_dev - restore pinctrl state from suspend for a device
1140 *
1141 * Restore one of the banks that was saved during suspend.
1142 *
1143 * We don't bother doing anything complicated to avoid glitching lines since
1144 * we're called before pad retention is turned off.
1145 */
1146static void samsung_pinctrl_resume_dev(struct samsung_pinctrl_drv_data *drvdata)
1147{
1148	void __iomem *virt_base = drvdata->virt_base;
1149	int i;
1150
1151	if (drvdata->resume)
1152		drvdata->resume(drvdata);
1153
1154	for (i = 0; i < drvdata->nr_banks; i++) {
1155		struct samsung_pin_bank *bank = &drvdata->pin_banks[i];
1156		void __iomem *reg = virt_base + bank->pctl_offset;
1157		const u8 *offs = bank->type->reg_offset;
1158		const u8 *widths = bank->type->fld_width;
1159		enum pincfg_type type;
1160
1161		/* Registers without a powerdown config aren't lost */
1162		if (!widths[PINCFG_TYPE_CON_PDN])
1163			continue;
1164
1165		if (widths[PINCFG_TYPE_FUNC] * bank->nr_pins > 32) {
1166			/* Some banks have two config registers */
1167			pr_debug("%s @ %p (con %#010x %08x => %#010x %08x)\n",
1168				 bank->name, reg,
1169				 readl(reg + offs[PINCFG_TYPE_FUNC]),
1170				 readl(reg + offs[PINCFG_TYPE_FUNC] + 4),
1171				 bank->pm_save[PINCFG_TYPE_FUNC],
1172				 bank->pm_save[PINCFG_TYPE_NUM]);
1173			writel(bank->pm_save[PINCFG_TYPE_NUM],
1174			       reg + offs[PINCFG_TYPE_FUNC] + 4);
1175		} else {
1176			pr_debug("%s @ %p (con %#010x => %#010x)\n", bank->name,
1177				 reg, readl(reg + offs[PINCFG_TYPE_FUNC]),
1178				 bank->pm_save[PINCFG_TYPE_FUNC]);
1179		}
1180		for (type = 0; type < PINCFG_TYPE_NUM; type++)
1181			if (widths[type])
1182				writel(bank->pm_save[type], reg + offs[type]);
1183	}
1184}
1185
1186/**
1187 * samsung_pinctrl_suspend - save pinctrl state for suspend
1188 *
1189 * Save data for all banks across all devices.
1190 */
1191static int samsung_pinctrl_suspend(void)
1192{
1193	struct samsung_pinctrl_drv_data *drvdata;
1194
1195	list_for_each_entry(drvdata, &drvdata_list, node) {
1196		samsung_pinctrl_suspend_dev(drvdata);
1197	}
1198
1199	return 0;
1200}
1201
1202/**
1203 * samsung_pinctrl_resume - restore pinctrl state for suspend
1204 *
1205 * Restore data for all banks across all devices.
1206 */
1207static void samsung_pinctrl_resume(void)
1208{
1209	struct samsung_pinctrl_drv_data *drvdata;
1210
1211	list_for_each_entry_reverse(drvdata, &drvdata_list, node) {
1212		samsung_pinctrl_resume_dev(drvdata);
1213	}
1214}
1215
1216#else
1217#define samsung_pinctrl_suspend		NULL
1218#define samsung_pinctrl_resume		NULL
1219#endif
1220
1221static struct syscore_ops samsung_pinctrl_syscore_ops = {
1222	.suspend	= samsung_pinctrl_suspend,
1223	.resume		= samsung_pinctrl_resume,
1224};
1225
1226static const struct of_device_id samsung_pinctrl_dt_match[] = {
1227#ifdef CONFIG_PINCTRL_EXYNOS
1228	{ .compatible = "samsung,exynos3250-pinctrl",
1229		.data = (void *)exynos3250_pin_ctrl },
1230	{ .compatible = "samsung,exynos4210-pinctrl",
1231		.data = (void *)exynos4210_pin_ctrl },
1232	{ .compatible = "samsung,exynos4x12-pinctrl",
1233		.data = (void *)exynos4x12_pin_ctrl },
1234	{ .compatible = "samsung,exynos4415-pinctrl",
1235		.data = (void *)exynos4415_pin_ctrl },
1236	{ .compatible = "samsung,exynos5250-pinctrl",
1237		.data = (void *)exynos5250_pin_ctrl },
1238	{ .compatible = "samsung,exynos5260-pinctrl",
1239		.data = (void *)exynos5260_pin_ctrl },
1240	{ .compatible = "samsung,exynos5420-pinctrl",
1241		.data = (void *)exynos5420_pin_ctrl },
1242	{ .compatible = "samsung,exynos5433-pinctrl",
1243		.data = (void *)exynos5433_pin_ctrl },
1244	{ .compatible = "samsung,s5pv210-pinctrl",
1245		.data = (void *)s5pv210_pin_ctrl },
1246	{ .compatible = "samsung,exynos7-pinctrl",
1247		.data = (void *)exynos7_pin_ctrl },
1248#endif
1249#ifdef CONFIG_PINCTRL_S3C64XX
1250	{ .compatible = "samsung,s3c64xx-pinctrl",
1251		.data = s3c64xx_pin_ctrl },
1252#endif
1253#ifdef CONFIG_PINCTRL_S3C24XX
1254	{ .compatible = "samsung,s3c2412-pinctrl",
1255		.data = s3c2412_pin_ctrl },
1256	{ .compatible = "samsung,s3c2416-pinctrl",
1257		.data = s3c2416_pin_ctrl },
1258	{ .compatible = "samsung,s3c2440-pinctrl",
1259		.data = s3c2440_pin_ctrl },
1260	{ .compatible = "samsung,s3c2450-pinctrl",
1261		.data = s3c2450_pin_ctrl },
1262#endif
1263	{},
1264};
1265MODULE_DEVICE_TABLE(of, samsung_pinctrl_dt_match);
1266
1267static struct platform_driver samsung_pinctrl_driver = {
1268	.probe		= samsung_pinctrl_probe,
1269	.driver = {
1270		.name	= "samsung-pinctrl",
1271		.of_match_table = samsung_pinctrl_dt_match,
1272	},
1273};
1274
1275static int __init samsung_pinctrl_drv_register(void)
1276{
1277	/*
1278	 * Register syscore ops for save/restore of registers across suspend.
1279	 * It's important to ensure that this driver is running at an earlier
1280	 * initcall level than any arch-specific init calls that install syscore
1281	 * ops that turn off pad retention (like exynos_pm_resume).
1282	 */
1283	register_syscore_ops(&samsung_pinctrl_syscore_ops);
1284
1285	return platform_driver_register(&samsung_pinctrl_driver);
1286}
1287postcore_initcall(samsung_pinctrl_drv_register);
1288
1289static void __exit samsung_pinctrl_drv_unregister(void)
1290{
1291	platform_driver_unregister(&samsung_pinctrl_driver);
1292}
1293module_exit(samsung_pinctrl_drv_unregister);
1294
1295MODULE_AUTHOR("Thomas Abraham <thomas.ab@samsung.com>");
1296MODULE_DESCRIPTION("Samsung pinctrl driver");
1297MODULE_LICENSE("GPL v2");
1298