1/*
2 * pin-controller/pin-mux/pin-config/gpio-driver for Samsung's EXYNOS5440 SoC.
3 *
4 * Copyright (c) 2012 Samsung Electronics Co., Ltd.
5 *		http://www.samsung.com
6 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation; either version 2 of the License, or
10 * (at your option) any later version.
11 */
12
13#include <linux/module.h>
14#include <linux/platform_device.h>
15#include <linux/io.h>
16#include <linux/slab.h>
17#include <linux/err.h>
18#include <linux/gpio.h>
19#include <linux/device.h>
20#include <linux/pinctrl/pinctrl.h>
21#include <linux/pinctrl/pinmux.h>
22#include <linux/pinctrl/pinconf.h>
23#include <linux/interrupt.h>
24#include <linux/irqdomain.h>
25#include <linux/of_irq.h>
26#include "../core.h"
27
28/* EXYNOS5440 GPIO and Pinctrl register offsets */
29#define GPIO_MUX		0x00
30#define GPIO_IE			0x04
31#define GPIO_INT		0x08
32#define GPIO_TYPE		0x0C
33#define GPIO_VAL		0x10
34#define GPIO_OE			0x14
35#define GPIO_IN			0x18
36#define GPIO_PE			0x1C
37#define GPIO_PS			0x20
38#define GPIO_SR			0x24
39#define GPIO_DS0		0x28
40#define GPIO_DS1		0x2C
41
42#define EXYNOS5440_MAX_PINS		23
43#define EXYNOS5440_MAX_GPIO_INT	8
44#define PIN_NAME_LENGTH		10
45
46#define GROUP_SUFFIX		"-grp"
47#define GSUFFIX_LEN		sizeof(GROUP_SUFFIX)
48#define FUNCTION_SUFFIX		"-mux"
49#define FSUFFIX_LEN		sizeof(FUNCTION_SUFFIX)
50
51/*
52 * pin configuration type and its value are packed together into a 16-bits.
53 * The upper 8-bits represent the configuration type and the lower 8-bits
54 * hold the value of the configuration type.
55 */
56#define PINCFG_TYPE_MASK		0xFF
57#define PINCFG_VALUE_SHIFT		8
58#define PINCFG_VALUE_MASK		(0xFF << PINCFG_VALUE_SHIFT)
59#define PINCFG_PACK(type, value)	(((value) << PINCFG_VALUE_SHIFT) | type)
60#define PINCFG_UNPACK_TYPE(cfg)		((cfg) & PINCFG_TYPE_MASK)
61#define PINCFG_UNPACK_VALUE(cfg)	(((cfg) & PINCFG_VALUE_MASK) >> \
62						PINCFG_VALUE_SHIFT)
63
64/**
65 * enum pincfg_type - possible pin configuration types supported.
66 * @PINCFG_TYPE_PUD: Pull up/down configuration.
67 * @PINCFG_TYPE_DRV: Drive strength configuration.
68 * @PINCFG_TYPE_SKEW_RATE: Skew rate configuration.
69 * @PINCFG_TYPE_INPUT_TYPE: Pin input type configuration.
70 */
71enum pincfg_type {
72	PINCFG_TYPE_PUD,
73	PINCFG_TYPE_DRV,
74	PINCFG_TYPE_SKEW_RATE,
75	PINCFG_TYPE_INPUT_TYPE
76};
77
78/**
79 * struct exynos5440_pin_group: represent group of pins for pincfg setting.
80 * @name: name of the pin group, used to lookup the group.
81 * @pins: the pins included in this group.
82 * @num_pins: number of pins included in this group.
83 */
84struct exynos5440_pin_group {
85	const char		*name;
86	const unsigned int	*pins;
87	u8			num_pins;
88};
89
90/**
91 * struct exynos5440_pmx_func: represent a pin function.
92 * @name: name of the pin function, used to lookup the function.
93 * @groups: one or more names of pin groups that provide this function.
94 * @num_groups: number of groups included in @groups.
95 * @function: the function number to be programmed when selected.
96 */
97struct exynos5440_pmx_func {
98	const char		*name;
99	const char		**groups;
100	u8			num_groups;
101	unsigned long		function;
102};
103
104/**
105 * struct exynos5440_pinctrl_priv_data: driver's private runtime data.
106 * @reg_base: ioremapped based address of the register space.
107 * @gc: gpio chip registered with gpiolib.
108 * @pin_groups: list of pin groups parsed from device tree.
109 * @nr_groups: number of pin groups available.
110 * @pmx_functions: list of pin functions parsed from device tree.
111 * @nr_functions: number of pin functions available.
112 * @range: gpio range to register with pinctrl
113 */
114struct exynos5440_pinctrl_priv_data {
115	void __iomem			*reg_base;
116	struct gpio_chip		*gc;
117	struct irq_domain		*irq_domain;
118
119	const struct exynos5440_pin_group	*pin_groups;
120	unsigned int			nr_groups;
121	const struct exynos5440_pmx_func	*pmx_functions;
122	unsigned int			nr_functions;
123	struct pinctrl_gpio_range	range;
124};
125
126/**
127 * struct exynos5440_gpio_intr_data: private data for gpio interrupts.
128 * @priv: driver's private runtime data.
129 * @gpio_int: gpio interrupt number.
130 */
131struct exynos5440_gpio_intr_data {
132	struct exynos5440_pinctrl_priv_data	*priv;
133	unsigned int				gpio_int;
134};
135
136/* list of all possible config options supported */
137static struct pin_config {
138	char		*prop_cfg;
139	unsigned int	cfg_type;
140} pcfgs[] = {
141	{ "samsung,exynos5440-pin-pud", PINCFG_TYPE_PUD },
142	{ "samsung,exynos5440-pin-drv", PINCFG_TYPE_DRV },
143	{ "samsung,exynos5440-pin-skew-rate", PINCFG_TYPE_SKEW_RATE },
144	{ "samsung,exynos5440-pin-input-type", PINCFG_TYPE_INPUT_TYPE },
145};
146
147/* check if the selector is a valid pin group selector */
148static int exynos5440_get_group_count(struct pinctrl_dev *pctldev)
149{
150	struct exynos5440_pinctrl_priv_data *priv;
151
152	priv = pinctrl_dev_get_drvdata(pctldev);
153	return priv->nr_groups;
154}
155
156/* return the name of the group selected by the group selector */
157static const char *exynos5440_get_group_name(struct pinctrl_dev *pctldev,
158						unsigned selector)
159{
160	struct exynos5440_pinctrl_priv_data *priv;
161
162	priv = pinctrl_dev_get_drvdata(pctldev);
163	return priv->pin_groups[selector].name;
164}
165
166/* return the pin numbers associated with the specified group */
167static int exynos5440_get_group_pins(struct pinctrl_dev *pctldev,
168		unsigned selector, const unsigned **pins, unsigned *num_pins)
169{
170	struct exynos5440_pinctrl_priv_data *priv;
171
172	priv = pinctrl_dev_get_drvdata(pctldev);
173	*pins = priv->pin_groups[selector].pins;
174	*num_pins = priv->pin_groups[selector].num_pins;
175	return 0;
176}
177
178/* create pinctrl_map entries by parsing device tree nodes */
179static int exynos5440_dt_node_to_map(struct pinctrl_dev *pctldev,
180			struct device_node *np, struct pinctrl_map **maps,
181			unsigned *nmaps)
182{
183	struct device *dev = pctldev->dev;
184	struct pinctrl_map *map;
185	unsigned long *cfg = NULL;
186	char *gname, *fname;
187	int cfg_cnt = 0, map_cnt = 0, idx = 0;
188
189	/* count the number of config options specfied in the node */
190	for (idx = 0; idx < ARRAY_SIZE(pcfgs); idx++)
191		if (of_find_property(np, pcfgs[idx].prop_cfg, NULL))
192			cfg_cnt++;
193
194	/*
195	 * Find out the number of map entries to create. All the config options
196	 * can be accomadated into a single config map entry.
197	 */
198	if (cfg_cnt)
199		map_cnt = 1;
200	if (of_find_property(np, "samsung,exynos5440-pin-function", NULL))
201		map_cnt++;
202	if (!map_cnt) {
203		dev_err(dev, "node %s does not have either config or function "
204				"configurations\n", np->name);
205		return -EINVAL;
206	}
207
208	/* Allocate memory for pin-map entries */
209	map = kzalloc(sizeof(*map) * map_cnt, GFP_KERNEL);
210	if (!map) {
211		dev_err(dev, "could not alloc memory for pin-maps\n");
212		return -ENOMEM;
213	}
214	*nmaps = 0;
215
216	/*
217	 * Allocate memory for pin group name. The pin group name is derived
218	 * from the node name from which these map entries are be created.
219	 */
220	gname = kzalloc(strlen(np->name) + GSUFFIX_LEN, GFP_KERNEL);
221	if (!gname) {
222		dev_err(dev, "failed to alloc memory for group name\n");
223		goto free_map;
224	}
225	snprintf(gname, strlen(np->name) + 4, "%s%s", np->name, GROUP_SUFFIX);
226
227	/*
228	 * don't have config options? then skip over to creating function
229	 * map entries.
230	 */
231	if (!cfg_cnt)
232		goto skip_cfgs;
233
234	/* Allocate memory for config entries */
235	cfg = kzalloc(sizeof(*cfg) * cfg_cnt, GFP_KERNEL);
236	if (!cfg) {
237		dev_err(dev, "failed to alloc memory for configs\n");
238		goto free_gname;
239	}
240
241	/* Prepare a list of config settings */
242	for (idx = 0, cfg_cnt = 0; idx < ARRAY_SIZE(pcfgs); idx++) {
243		u32 value;
244		if (!of_property_read_u32(np, pcfgs[idx].prop_cfg, &value))
245			cfg[cfg_cnt++] =
246				PINCFG_PACK(pcfgs[idx].cfg_type, value);
247	}
248
249	/* create the config map entry */
250	map[*nmaps].data.configs.group_or_pin = gname;
251	map[*nmaps].data.configs.configs = cfg;
252	map[*nmaps].data.configs.num_configs = cfg_cnt;
253	map[*nmaps].type = PIN_MAP_TYPE_CONFIGS_GROUP;
254	*nmaps += 1;
255
256skip_cfgs:
257	/* create the function map entry */
258	if (of_find_property(np, "samsung,exynos5440-pin-function", NULL)) {
259		fname = kzalloc(strlen(np->name) + FSUFFIX_LEN,	GFP_KERNEL);
260		if (!fname) {
261			dev_err(dev, "failed to alloc memory for func name\n");
262			goto free_cfg;
263		}
264		snprintf(fname, strlen(np->name) + 4, "%s%s", np->name,
265			 FUNCTION_SUFFIX);
266
267		map[*nmaps].data.mux.group = gname;
268		map[*nmaps].data.mux.function = fname;
269		map[*nmaps].type = PIN_MAP_TYPE_MUX_GROUP;
270		*nmaps += 1;
271	}
272
273	*maps = map;
274	return 0;
275
276free_cfg:
277	kfree(cfg);
278free_gname:
279	kfree(gname);
280free_map:
281	kfree(map);
282	return -ENOMEM;
283}
284
285/* free the memory allocated to hold the pin-map table */
286static void exynos5440_dt_free_map(struct pinctrl_dev *pctldev,
287			     struct pinctrl_map *map, unsigned num_maps)
288{
289	int idx;
290
291	for (idx = 0; idx < num_maps; idx++) {
292		if (map[idx].type == PIN_MAP_TYPE_MUX_GROUP) {
293			kfree(map[idx].data.mux.function);
294			if (!idx)
295				kfree(map[idx].data.mux.group);
296		} else if (map->type == PIN_MAP_TYPE_CONFIGS_GROUP) {
297			kfree(map[idx].data.configs.configs);
298			if (!idx)
299				kfree(map[idx].data.configs.group_or_pin);
300		}
301	};
302
303	kfree(map);
304}
305
306/* list of pinctrl callbacks for the pinctrl core */
307static const struct pinctrl_ops exynos5440_pctrl_ops = {
308	.get_groups_count	= exynos5440_get_group_count,
309	.get_group_name		= exynos5440_get_group_name,
310	.get_group_pins		= exynos5440_get_group_pins,
311	.dt_node_to_map		= exynos5440_dt_node_to_map,
312	.dt_free_map		= exynos5440_dt_free_map,
313};
314
315/* check if the selector is a valid pin function selector */
316static int exynos5440_get_functions_count(struct pinctrl_dev *pctldev)
317{
318	struct exynos5440_pinctrl_priv_data *priv;
319
320	priv = pinctrl_dev_get_drvdata(pctldev);
321	return priv->nr_functions;
322}
323
324/* return the name of the pin function specified */
325static const char *exynos5440_pinmux_get_fname(struct pinctrl_dev *pctldev,
326						unsigned selector)
327{
328	struct exynos5440_pinctrl_priv_data *priv;
329
330	priv = pinctrl_dev_get_drvdata(pctldev);
331	return priv->pmx_functions[selector].name;
332}
333
334/* return the groups associated for the specified function selector */
335static int exynos5440_pinmux_get_groups(struct pinctrl_dev *pctldev,
336		unsigned selector, const char * const **groups,
337		unsigned * const num_groups)
338{
339	struct exynos5440_pinctrl_priv_data *priv;
340
341	priv = pinctrl_dev_get_drvdata(pctldev);
342	*groups = priv->pmx_functions[selector].groups;
343	*num_groups = priv->pmx_functions[selector].num_groups;
344	return 0;
345}
346
347/* enable or disable a pinmux function */
348static void exynos5440_pinmux_setup(struct pinctrl_dev *pctldev, unsigned selector,
349					unsigned group, bool enable)
350{
351	struct exynos5440_pinctrl_priv_data *priv;
352	void __iomem *base;
353	u32 function;
354	u32 data;
355
356	priv = pinctrl_dev_get_drvdata(pctldev);
357	base = priv->reg_base;
358	function = priv->pmx_functions[selector].function;
359
360	data = readl(base + GPIO_MUX);
361	if (enable)
362		data |= (1 << function);
363	else
364		data &= ~(1 << function);
365	writel(data, base + GPIO_MUX);
366}
367
368/* enable a specified pinmux by writing to registers */
369static int exynos5440_pinmux_set_mux(struct pinctrl_dev *pctldev,
370				     unsigned selector,
371				     unsigned group)
372{
373	exynos5440_pinmux_setup(pctldev, selector, group, true);
374	return 0;
375}
376
377/*
378 * The calls to gpio_direction_output() and gpio_direction_input()
379 * leads to this function call (via the pinctrl_gpio_direction_{input|output}()
380 * function called from the gpiolib interface).
381 */
382static int exynos5440_pinmux_gpio_set_direction(struct pinctrl_dev *pctldev,
383		struct pinctrl_gpio_range *range, unsigned offset, bool input)
384{
385	return 0;
386}
387
388/* list of pinmux callbacks for the pinmux vertical in pinctrl core */
389static const struct pinmux_ops exynos5440_pinmux_ops = {
390	.get_functions_count	= exynos5440_get_functions_count,
391	.get_function_name	= exynos5440_pinmux_get_fname,
392	.get_function_groups	= exynos5440_pinmux_get_groups,
393	.set_mux		= exynos5440_pinmux_set_mux,
394	.gpio_set_direction	= exynos5440_pinmux_gpio_set_direction,
395};
396
397/* set the pin config settings for a specified pin */
398static int exynos5440_pinconf_set(struct pinctrl_dev *pctldev, unsigned int pin,
399				unsigned long *configs,
400				unsigned num_configs)
401{
402	struct exynos5440_pinctrl_priv_data *priv;
403	void __iomem *base;
404	enum pincfg_type cfg_type;
405	u32 cfg_value;
406	u32 data;
407	int i;
408
409	priv = pinctrl_dev_get_drvdata(pctldev);
410	base = priv->reg_base;
411
412	for (i = 0; i < num_configs; i++) {
413		cfg_type = PINCFG_UNPACK_TYPE(configs[i]);
414		cfg_value = PINCFG_UNPACK_VALUE(configs[i]);
415
416		switch (cfg_type) {
417		case PINCFG_TYPE_PUD:
418			/* first set pull enable/disable bit */
419			data = readl(base + GPIO_PE);
420			data &= ~(1 << pin);
421			if (cfg_value)
422				data |= (1 << pin);
423			writel(data, base + GPIO_PE);
424
425			/* then set pull up/down bit */
426			data = readl(base + GPIO_PS);
427			data &= ~(1 << pin);
428			if (cfg_value == 2)
429				data |= (1 << pin);
430			writel(data, base + GPIO_PS);
431			break;
432
433		case PINCFG_TYPE_DRV:
434			/* set the first bit of the drive strength */
435			data = readl(base + GPIO_DS0);
436			data &= ~(1 << pin);
437			data |= ((cfg_value & 1) << pin);
438			writel(data, base + GPIO_DS0);
439			cfg_value >>= 1;
440
441			/* set the second bit of the driver strength */
442			data = readl(base + GPIO_DS1);
443			data &= ~(1 << pin);
444			data |= ((cfg_value & 1) << pin);
445			writel(data, base + GPIO_DS1);
446			break;
447		case PINCFG_TYPE_SKEW_RATE:
448			data = readl(base + GPIO_SR);
449			data &= ~(1 << pin);
450			data |= ((cfg_value & 1) << pin);
451			writel(data, base + GPIO_SR);
452			break;
453		case PINCFG_TYPE_INPUT_TYPE:
454			data = readl(base + GPIO_TYPE);
455			data &= ~(1 << pin);
456			data |= ((cfg_value & 1) << pin);
457			writel(data, base + GPIO_TYPE);
458			break;
459		default:
460			WARN_ON(1);
461			return -EINVAL;
462		}
463	} /* for each config */
464
465	return 0;
466}
467
468/* get the pin config settings for a specified pin */
469static int exynos5440_pinconf_get(struct pinctrl_dev *pctldev, unsigned int pin,
470					unsigned long *config)
471{
472	struct exynos5440_pinctrl_priv_data *priv;
473	void __iomem *base;
474	enum pincfg_type cfg_type = PINCFG_UNPACK_TYPE(*config);
475	u32 data;
476
477	priv = pinctrl_dev_get_drvdata(pctldev);
478	base = priv->reg_base;
479
480	switch (cfg_type) {
481	case PINCFG_TYPE_PUD:
482		data = readl(base + GPIO_PE);
483		data = (data >> pin) & 1;
484		if (!data)
485			*config = 0;
486		else
487			*config = ((readl(base + GPIO_PS) >> pin) & 1) + 1;
488		break;
489	case PINCFG_TYPE_DRV:
490		data = readl(base + GPIO_DS0);
491		data = (data >> pin) & 1;
492		*config = data;
493		data = readl(base + GPIO_DS1);
494		data = (data >> pin) & 1;
495		*config |= (data << 1);
496		break;
497	case PINCFG_TYPE_SKEW_RATE:
498		data = readl(base + GPIO_SR);
499		*config = (data >> pin) & 1;
500		break;
501	case PINCFG_TYPE_INPUT_TYPE:
502		data = readl(base + GPIO_TYPE);
503		*config = (data >> pin) & 1;
504		break;
505	default:
506		WARN_ON(1);
507		return -EINVAL;
508	}
509
510	return 0;
511}
512
513/* set the pin config settings for a specified pin group */
514static int exynos5440_pinconf_group_set(struct pinctrl_dev *pctldev,
515			unsigned group, unsigned long *configs,
516			unsigned num_configs)
517{
518	struct exynos5440_pinctrl_priv_data *priv;
519	const unsigned int *pins;
520	unsigned int cnt;
521
522	priv = pinctrl_dev_get_drvdata(pctldev);
523	pins = priv->pin_groups[group].pins;
524
525	for (cnt = 0; cnt < priv->pin_groups[group].num_pins; cnt++)
526		exynos5440_pinconf_set(pctldev, pins[cnt], configs,
527				       num_configs);
528
529	return 0;
530}
531
532/* get the pin config settings for a specified pin group */
533static int exynos5440_pinconf_group_get(struct pinctrl_dev *pctldev,
534				unsigned int group, unsigned long *config)
535{
536	struct exynos5440_pinctrl_priv_data *priv;
537	const unsigned int *pins;
538
539	priv = pinctrl_dev_get_drvdata(pctldev);
540	pins = priv->pin_groups[group].pins;
541	exynos5440_pinconf_get(pctldev, pins[0], config);
542	return 0;
543}
544
545/* list of pinconfig callbacks for pinconfig vertical in the pinctrl code */
546static const struct pinconf_ops exynos5440_pinconf_ops = {
547	.pin_config_get		= exynos5440_pinconf_get,
548	.pin_config_set		= exynos5440_pinconf_set,
549	.pin_config_group_get	= exynos5440_pinconf_group_get,
550	.pin_config_group_set	= exynos5440_pinconf_group_set,
551};
552
553/* gpiolib gpio_set callback function */
554static void exynos5440_gpio_set(struct gpio_chip *gc, unsigned offset, int value)
555{
556	struct exynos5440_pinctrl_priv_data *priv = dev_get_drvdata(gc->dev);
557	void __iomem *base = priv->reg_base;
558	u32 data;
559
560	data = readl(base + GPIO_VAL);
561	data &= ~(1 << offset);
562	if (value)
563		data |= 1 << offset;
564	writel(data, base + GPIO_VAL);
565}
566
567/* gpiolib gpio_get callback function */
568static int exynos5440_gpio_get(struct gpio_chip *gc, unsigned offset)
569{
570	struct exynos5440_pinctrl_priv_data *priv = dev_get_drvdata(gc->dev);
571	void __iomem *base = priv->reg_base;
572	u32 data;
573
574	data = readl(base + GPIO_IN);
575	data >>= offset;
576	data &= 1;
577	return data;
578}
579
580/* gpiolib gpio_direction_input callback function */
581static int exynos5440_gpio_direction_input(struct gpio_chip *gc, unsigned offset)
582{
583	struct exynos5440_pinctrl_priv_data *priv = dev_get_drvdata(gc->dev);
584	void __iomem *base = priv->reg_base;
585	u32 data;
586
587	/* first disable the data output enable on this pin */
588	data = readl(base + GPIO_OE);
589	data &= ~(1 << offset);
590	writel(data, base + GPIO_OE);
591
592	/* now enable input on this pin */
593	data =  readl(base + GPIO_IE);
594	data |= 1 << offset;
595	writel(data, base + GPIO_IE);
596	return 0;
597}
598
599/* gpiolib gpio_direction_output callback function */
600static int exynos5440_gpio_direction_output(struct gpio_chip *gc, unsigned offset,
601							int value)
602{
603	struct exynos5440_pinctrl_priv_data *priv = dev_get_drvdata(gc->dev);
604	void __iomem *base = priv->reg_base;
605	u32 data;
606
607	exynos5440_gpio_set(gc, offset, value);
608
609	/* first disable the data input enable on this pin */
610	data = readl(base + GPIO_IE);
611	data &= ~(1 << offset);
612	writel(data, base + GPIO_IE);
613
614	/* now enable output on this pin */
615	data =  readl(base + GPIO_OE);
616	data |= 1 << offset;
617	writel(data, base + GPIO_OE);
618	return 0;
619}
620
621/* gpiolib gpio_to_irq callback function */
622static int exynos5440_gpio_to_irq(struct gpio_chip *gc, unsigned offset)
623{
624	struct exynos5440_pinctrl_priv_data *priv = dev_get_drvdata(gc->dev);
625	unsigned int virq;
626
627	if (offset < 16 || offset > 23)
628		return -ENXIO;
629
630	if (!priv->irq_domain)
631		return -ENXIO;
632
633	virq = irq_create_mapping(priv->irq_domain, offset - 16);
634	return virq ? : -ENXIO;
635}
636
637/* parse the pin numbers listed in the 'samsung,exynos5440-pins' property */
638static int exynos5440_pinctrl_parse_dt_pins(struct platform_device *pdev,
639			struct device_node *cfg_np, unsigned int **pin_list,
640			unsigned int *npins)
641{
642	struct device *dev = &pdev->dev;
643	struct property *prop;
644
645	prop = of_find_property(cfg_np, "samsung,exynos5440-pins", NULL);
646	if (!prop)
647		return -ENOENT;
648
649	*npins = prop->length / sizeof(unsigned long);
650	if (!*npins) {
651		dev_err(dev, "invalid pin list in %s node", cfg_np->name);
652		return -EINVAL;
653	}
654
655	*pin_list = devm_kzalloc(dev, *npins * sizeof(**pin_list), GFP_KERNEL);
656	if (!*pin_list) {
657		dev_err(dev, "failed to allocate memory for pin list\n");
658		return -ENOMEM;
659	}
660
661	return of_property_read_u32_array(cfg_np, "samsung,exynos5440-pins",
662			*pin_list, *npins);
663}
664
665/*
666 * Parse the information about all the available pin groups and pin functions
667 * from device node of the pin-controller.
668 */
669static int exynos5440_pinctrl_parse_dt(struct platform_device *pdev,
670				struct exynos5440_pinctrl_priv_data *priv)
671{
672	struct device *dev = &pdev->dev;
673	struct device_node *dev_np = dev->of_node;
674	struct device_node *cfg_np;
675	struct exynos5440_pin_group *groups, *grp;
676	struct exynos5440_pmx_func *functions, *func;
677	unsigned *pin_list;
678	unsigned int npins, grp_cnt, func_idx = 0;
679	char *gname, *fname;
680	int ret;
681
682	grp_cnt = of_get_child_count(dev_np);
683	if (!grp_cnt)
684		return -EINVAL;
685
686	groups = devm_kzalloc(dev, grp_cnt * sizeof(*groups), GFP_KERNEL);
687	if (!groups) {
688		dev_err(dev, "failed allocate memory for ping group list\n");
689		return -EINVAL;
690	}
691	grp = groups;
692
693	functions = devm_kzalloc(dev, grp_cnt * sizeof(*functions), GFP_KERNEL);
694	if (!functions) {
695		dev_err(dev, "failed to allocate memory for function list\n");
696		return -EINVAL;
697	}
698	func = functions;
699
700	/*
701	 * Iterate over all the child nodes of the pin controller node
702	 * and create pin groups and pin function lists.
703	 */
704	for_each_child_of_node(dev_np, cfg_np) {
705		u32 function;
706
707		ret = exynos5440_pinctrl_parse_dt_pins(pdev, cfg_np,
708					&pin_list, &npins);
709		if (ret) {
710			gname = NULL;
711			goto skip_to_pin_function;
712		}
713
714		/* derive pin group name from the node name */
715		gname = devm_kzalloc(dev, strlen(cfg_np->name) + GSUFFIX_LEN,
716					GFP_KERNEL);
717		if (!gname) {
718			dev_err(dev, "failed to alloc memory for group name\n");
719			return -ENOMEM;
720		}
721		snprintf(gname, strlen(cfg_np->name) + 4, "%s%s", cfg_np->name,
722			 GROUP_SUFFIX);
723
724		grp->name = gname;
725		grp->pins = pin_list;
726		grp->num_pins = npins;
727		grp++;
728
729skip_to_pin_function:
730		ret = of_property_read_u32(cfg_np, "samsung,exynos5440-pin-function",
731						&function);
732		if (ret)
733			continue;
734
735		/* derive function name from the node name */
736		fname = devm_kzalloc(dev, strlen(cfg_np->name) + FSUFFIX_LEN,
737					GFP_KERNEL);
738		if (!fname) {
739			dev_err(dev, "failed to alloc memory for func name\n");
740			return -ENOMEM;
741		}
742		snprintf(fname, strlen(cfg_np->name) + 4, "%s%s", cfg_np->name,
743			 FUNCTION_SUFFIX);
744
745		func->name = fname;
746		func->groups = devm_kzalloc(dev, sizeof(char *), GFP_KERNEL);
747		if (!func->groups) {
748			dev_err(dev, "failed to alloc memory for group list "
749					"in pin function");
750			return -ENOMEM;
751		}
752		func->groups[0] = gname;
753		func->num_groups = gname ? 1 : 0;
754		func->function = function;
755		func++;
756		func_idx++;
757	}
758
759	priv->pin_groups = groups;
760	priv->nr_groups = grp_cnt;
761	priv->pmx_functions = functions;
762	priv->nr_functions = func_idx;
763	return 0;
764}
765
766/* register the pinctrl interface with the pinctrl subsystem */
767static int exynos5440_pinctrl_register(struct platform_device *pdev,
768				struct exynos5440_pinctrl_priv_data *priv)
769{
770	struct device *dev = &pdev->dev;
771	struct pinctrl_desc *ctrldesc;
772	struct pinctrl_dev *pctl_dev;
773	struct pinctrl_pin_desc *pindesc, *pdesc;
774	char *pin_names;
775	int pin, ret;
776
777	ctrldesc = devm_kzalloc(dev, sizeof(*ctrldesc), GFP_KERNEL);
778	if (!ctrldesc) {
779		dev_err(dev, "could not allocate memory for pinctrl desc\n");
780		return -ENOMEM;
781	}
782
783	ctrldesc->name = "exynos5440-pinctrl";
784	ctrldesc->owner = THIS_MODULE;
785	ctrldesc->pctlops = &exynos5440_pctrl_ops;
786	ctrldesc->pmxops = &exynos5440_pinmux_ops;
787	ctrldesc->confops = &exynos5440_pinconf_ops;
788
789	pindesc = devm_kzalloc(&pdev->dev, sizeof(*pindesc) *
790				EXYNOS5440_MAX_PINS, GFP_KERNEL);
791	if (!pindesc) {
792		dev_err(&pdev->dev, "mem alloc for pin descriptors failed\n");
793		return -ENOMEM;
794	}
795	ctrldesc->pins = pindesc;
796	ctrldesc->npins = EXYNOS5440_MAX_PINS;
797
798	/* dynamically populate the pin number and pin name for pindesc */
799	for (pin = 0, pdesc = pindesc; pin < ctrldesc->npins; pin++, pdesc++)
800		pdesc->number = pin;
801
802	/*
803	 * allocate space for storing the dynamically generated names for all
804	 * the pins which belong to this pin-controller.
805	 */
806	pin_names = devm_kzalloc(&pdev->dev, sizeof(char) * PIN_NAME_LENGTH *
807					ctrldesc->npins, GFP_KERNEL);
808	if (!pin_names) {
809		dev_err(&pdev->dev, "mem alloc for pin names failed\n");
810		return -ENOMEM;
811	}
812
813	/* for each pin, set the name of the pin */
814	for (pin = 0; pin < ctrldesc->npins; pin++) {
815		snprintf(pin_names, 6, "gpio%02d", pin);
816		pdesc = pindesc + pin;
817		pdesc->name = pin_names;
818		pin_names += PIN_NAME_LENGTH;
819	}
820
821	ret = exynos5440_pinctrl_parse_dt(pdev, priv);
822	if (ret)
823		return ret;
824
825	pctl_dev = pinctrl_register(ctrldesc, &pdev->dev, priv);
826	if (!pctl_dev) {
827		dev_err(&pdev->dev, "could not register pinctrl driver\n");
828		return -EINVAL;
829	}
830
831	priv->range.name = "exynos5440-pctrl-gpio-range";
832	priv->range.id = 0;
833	priv->range.base = 0;
834	priv->range.npins = EXYNOS5440_MAX_PINS;
835	priv->range.gc = priv->gc;
836	pinctrl_add_gpio_range(pctl_dev, &priv->range);
837	return 0;
838}
839
840/* register the gpiolib interface with the gpiolib subsystem */
841static int exynos5440_gpiolib_register(struct platform_device *pdev,
842				struct exynos5440_pinctrl_priv_data *priv)
843{
844	struct gpio_chip *gc;
845	int ret;
846
847	gc = devm_kzalloc(&pdev->dev, sizeof(*gc), GFP_KERNEL);
848	if (!gc) {
849		dev_err(&pdev->dev, "mem alloc for gpio_chip failed\n");
850		return -ENOMEM;
851	}
852
853	priv->gc = gc;
854	gc->base = 0;
855	gc->ngpio = EXYNOS5440_MAX_PINS;
856	gc->dev = &pdev->dev;
857	gc->set = exynos5440_gpio_set;
858	gc->get = exynos5440_gpio_get;
859	gc->direction_input = exynos5440_gpio_direction_input;
860	gc->direction_output = exynos5440_gpio_direction_output;
861	gc->to_irq = exynos5440_gpio_to_irq;
862	gc->label = "gpiolib-exynos5440";
863	gc->owner = THIS_MODULE;
864	ret = gpiochip_add(gc);
865	if (ret) {
866		dev_err(&pdev->dev, "failed to register gpio_chip %s, error "
867					"code: %d\n", gc->label, ret);
868		return ret;
869	}
870
871	return 0;
872}
873
874/* unregister the gpiolib interface with the gpiolib subsystem */
875static int exynos5440_gpiolib_unregister(struct platform_device *pdev,
876				struct exynos5440_pinctrl_priv_data *priv)
877{
878	gpiochip_remove(priv->gc);
879	return 0;
880}
881
882static void exynos5440_gpio_irq_unmask(struct irq_data *irqd)
883{
884	struct exynos5440_pinctrl_priv_data *d;
885	unsigned long gpio_int;
886
887	d = irq_data_get_irq_chip_data(irqd);
888	gpio_int = readl(d->reg_base + GPIO_INT);
889	gpio_int |= 1 << irqd->hwirq;
890	writel(gpio_int, d->reg_base + GPIO_INT);
891}
892
893static void exynos5440_gpio_irq_mask(struct irq_data *irqd)
894{
895	struct exynos5440_pinctrl_priv_data *d;
896	unsigned long gpio_int;
897
898	d = irq_data_get_irq_chip_data(irqd);
899	gpio_int = readl(d->reg_base + GPIO_INT);
900	gpio_int &= ~(1 << irqd->hwirq);
901	writel(gpio_int, d->reg_base + GPIO_INT);
902}
903
904/* irq_chip for gpio interrupts */
905static struct irq_chip exynos5440_gpio_irq_chip = {
906	.name		= "exynos5440_gpio_irq_chip",
907	.irq_unmask	= exynos5440_gpio_irq_unmask,
908	.irq_mask	= exynos5440_gpio_irq_mask,
909};
910
911/* interrupt handler for GPIO interrupts 0..7 */
912static irqreturn_t exynos5440_gpio_irq(int irq, void *data)
913{
914	struct exynos5440_gpio_intr_data *intd = data;
915	struct exynos5440_pinctrl_priv_data *d = intd->priv;
916	int virq;
917
918	virq = irq_linear_revmap(d->irq_domain, intd->gpio_int);
919	if (!virq)
920		return IRQ_NONE;
921	generic_handle_irq(virq);
922	return IRQ_HANDLED;
923}
924
925static int exynos5440_gpio_irq_map(struct irq_domain *h, unsigned int virq,
926					irq_hw_number_t hw)
927{
928	struct exynos5440_pinctrl_priv_data *d = h->host_data;
929
930	irq_set_chip_data(virq, d);
931	irq_set_chip_and_handler(virq, &exynos5440_gpio_irq_chip,
932					handle_level_irq);
933	set_irq_flags(virq, IRQF_VALID);
934	return 0;
935}
936
937/* irq domain callbacks for gpio interrupt controller */
938static const struct irq_domain_ops exynos5440_gpio_irqd_ops = {
939	.map	= exynos5440_gpio_irq_map,
940	.xlate	= irq_domain_xlate_twocell,
941};
942
943/* setup handling of gpio interrupts */
944static int exynos5440_gpio_irq_init(struct platform_device *pdev,
945				struct exynos5440_pinctrl_priv_data *priv)
946{
947	struct device *dev = &pdev->dev;
948	struct exynos5440_gpio_intr_data *intd;
949	int i, irq, ret;
950
951	intd = devm_kzalloc(dev, sizeof(*intd) * EXYNOS5440_MAX_GPIO_INT,
952					GFP_KERNEL);
953	if (!intd) {
954		dev_err(dev, "failed to allocate memory for gpio intr data\n");
955		return -ENOMEM;
956	}
957
958	for (i = 0; i < EXYNOS5440_MAX_GPIO_INT; i++) {
959		irq = irq_of_parse_and_map(dev->of_node, i);
960		if (irq <= 0) {
961			dev_err(dev, "irq parsing failed\n");
962			return -EINVAL;
963		}
964
965		intd->gpio_int = i;
966		intd->priv = priv;
967		ret = devm_request_irq(dev, irq, exynos5440_gpio_irq,
968					0, dev_name(dev), intd++);
969		if (ret) {
970			dev_err(dev, "irq request failed\n");
971			return -ENXIO;
972		}
973	}
974
975	priv->irq_domain = irq_domain_add_linear(dev->of_node,
976				EXYNOS5440_MAX_GPIO_INT,
977				&exynos5440_gpio_irqd_ops, priv);
978	if (!priv->irq_domain) {
979		dev_err(dev, "failed to create irq domain\n");
980		return -ENXIO;
981	}
982
983	return 0;
984}
985
986static int exynos5440_pinctrl_probe(struct platform_device *pdev)
987{
988	struct device *dev = &pdev->dev;
989	struct exynos5440_pinctrl_priv_data *priv;
990	struct resource *res;
991	int ret;
992
993	if (!dev->of_node) {
994		dev_err(dev, "device tree node not found\n");
995		return -ENODEV;
996	}
997
998	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
999	if (!priv) {
1000		dev_err(dev, "could not allocate memory for private data\n");
1001		return -ENOMEM;
1002	}
1003
1004	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1005	priv->reg_base = devm_ioremap_resource(&pdev->dev, res);
1006	if (IS_ERR(priv->reg_base))
1007		return PTR_ERR(priv->reg_base);
1008
1009	ret = exynos5440_gpiolib_register(pdev, priv);
1010	if (ret)
1011		return ret;
1012
1013	ret = exynos5440_pinctrl_register(pdev, priv);
1014	if (ret) {
1015		exynos5440_gpiolib_unregister(pdev, priv);
1016		return ret;
1017	}
1018
1019	ret = exynos5440_gpio_irq_init(pdev, priv);
1020	if (ret) {
1021		dev_err(dev, "failed to setup gpio interrupts\n");
1022		return ret;
1023	}
1024
1025	platform_set_drvdata(pdev, priv);
1026	dev_info(dev, "EXYNOS5440 pinctrl driver registered\n");
1027	return 0;
1028}
1029
1030static const struct of_device_id exynos5440_pinctrl_dt_match[] = {
1031	{ .compatible = "samsung,exynos5440-pinctrl" },
1032	{},
1033};
1034MODULE_DEVICE_TABLE(of, exynos5440_pinctrl_dt_match);
1035
1036static struct platform_driver exynos5440_pinctrl_driver = {
1037	.probe		= exynos5440_pinctrl_probe,
1038	.driver = {
1039		.name	= "exynos5440-pinctrl",
1040		.of_match_table = exynos5440_pinctrl_dt_match,
1041	},
1042};
1043
1044static int __init exynos5440_pinctrl_drv_register(void)
1045{
1046	return platform_driver_register(&exynos5440_pinctrl_driver);
1047}
1048postcore_initcall(exynos5440_pinctrl_drv_register);
1049
1050static void __exit exynos5440_pinctrl_drv_unregister(void)
1051{
1052	platform_driver_unregister(&exynos5440_pinctrl_driver);
1053}
1054module_exit(exynos5440_pinctrl_drv_unregister);
1055
1056MODULE_AUTHOR("Thomas Abraham <thomas.ab@samsung.com>");
1057MODULE_DESCRIPTION("Samsung EXYNOS5440 SoC pinctrl driver");
1058MODULE_LICENSE("GPL v2");
1059