1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Pinctrl driver for the Wondermedia SoC's
4 *
5 * Copyright (c) 2013 Tony Prisk <linux@prisktech.co.nz>
6 */
7
8#include <linux/err.h>
9#include <linux/gpio/driver.h>
10#include <linux/interrupt.h>
11#include <linux/io.h>
12#include <linux/irq.h>
13#include <linux/of.h>
14#include <linux/of_irq.h>
15#include <linux/pinctrl/consumer.h>
16#include <linux/pinctrl/machine.h>
17#include <linux/pinctrl/pinconf.h>
18#include <linux/pinctrl/pinconf-generic.h>
19#include <linux/pinctrl/pinctrl.h>
20#include <linux/pinctrl/pinmux.h>
21#include <linux/platform_device.h>
22#include <linux/slab.h>
23
24#include "pinctrl-wmt.h"
25
26static inline void wmt_setbits(struct wmt_pinctrl_data *data, u32 reg,
27				 u32 mask)
28{
29	u32 val;
30
31	val = readl_relaxed(data->base + reg);
32	val |= mask;
33	writel_relaxed(val, data->base + reg);
34}
35
36static inline void wmt_clearbits(struct wmt_pinctrl_data *data, u32 reg,
37				   u32 mask)
38{
39	u32 val;
40
41	val = readl_relaxed(data->base + reg);
42	val &= ~mask;
43	writel_relaxed(val, data->base + reg);
44}
45
46enum wmt_func_sel {
47	WMT_FSEL_GPIO_IN = 0,
48	WMT_FSEL_GPIO_OUT = 1,
49	WMT_FSEL_ALT = 2,
50	WMT_FSEL_COUNT = 3,
51};
52
53static const char * const wmt_functions[WMT_FSEL_COUNT] = {
54	[WMT_FSEL_GPIO_IN] = "gpio_in",
55	[WMT_FSEL_GPIO_OUT] = "gpio_out",
56	[WMT_FSEL_ALT] = "alt",
57};
58
59static int wmt_pmx_get_functions_count(struct pinctrl_dev *pctldev)
60{
61	return WMT_FSEL_COUNT;
62}
63
64static const char *wmt_pmx_get_function_name(struct pinctrl_dev *pctldev,
65					     unsigned selector)
66{
67	return wmt_functions[selector];
68}
69
70static int wmt_pmx_get_function_groups(struct pinctrl_dev *pctldev,
71				       unsigned selector,
72				       const char * const **groups,
73				       unsigned * const num_groups)
74{
75	struct wmt_pinctrl_data *data = pinctrl_dev_get_drvdata(pctldev);
76
77	/* every pin does every function */
78	*groups = data->groups;
79	*num_groups = data->ngroups;
80
81	return 0;
82}
83
84static int wmt_set_pinmux(struct wmt_pinctrl_data *data, unsigned func,
85			  unsigned pin)
86{
87	u32 bank = WMT_BANK_FROM_PIN(pin);
88	u32 bit = WMT_BIT_FROM_PIN(pin);
89	u32 reg_en = data->banks[bank].reg_en;
90	u32 reg_dir = data->banks[bank].reg_dir;
91
92	if (reg_dir == NO_REG) {
93		dev_err(data->dev, "pin:%d no direction register defined\n",
94			pin);
95		return -EINVAL;
96	}
97
98	/*
99	 * If reg_en == NO_REG, we assume it is a dedicated GPIO and cannot be
100	 * disabled (as on VT8500) and that no alternate function is available.
101	 */
102	switch (func) {
103	case WMT_FSEL_GPIO_IN:
104		if (reg_en != NO_REG)
105			wmt_setbits(data, reg_en, BIT(bit));
106		wmt_clearbits(data, reg_dir, BIT(bit));
107		break;
108	case WMT_FSEL_GPIO_OUT:
109		if (reg_en != NO_REG)
110			wmt_setbits(data, reg_en, BIT(bit));
111		wmt_setbits(data, reg_dir, BIT(bit));
112		break;
113	case WMT_FSEL_ALT:
114		if (reg_en == NO_REG) {
115			dev_err(data->dev, "pin:%d no alt function available\n",
116				pin);
117			return -EINVAL;
118		}
119		wmt_clearbits(data, reg_en, BIT(bit));
120	}
121
122	return 0;
123}
124
125static int wmt_pmx_set_mux(struct pinctrl_dev *pctldev,
126			   unsigned func_selector,
127			   unsigned group_selector)
128{
129	struct wmt_pinctrl_data *data = pinctrl_dev_get_drvdata(pctldev);
130	u32 pinnum = data->pins[group_selector].number;
131
132	return wmt_set_pinmux(data, func_selector, pinnum);
133}
134
135static void wmt_pmx_gpio_disable_free(struct pinctrl_dev *pctldev,
136				      struct pinctrl_gpio_range *range,
137				      unsigned offset)
138{
139	struct wmt_pinctrl_data *data = pinctrl_dev_get_drvdata(pctldev);
140
141	/* disable by setting GPIO_IN */
142	wmt_set_pinmux(data, WMT_FSEL_GPIO_IN, offset);
143}
144
145static int wmt_pmx_gpio_set_direction(struct pinctrl_dev *pctldev,
146				      struct pinctrl_gpio_range *range,
147				      unsigned offset,
148				      bool input)
149{
150	struct wmt_pinctrl_data *data = pinctrl_dev_get_drvdata(pctldev);
151
152	wmt_set_pinmux(data, (input ? WMT_FSEL_GPIO_IN : WMT_FSEL_GPIO_OUT),
153		       offset);
154
155	return 0;
156}
157
158static const struct pinmux_ops wmt_pinmux_ops = {
159	.get_functions_count = wmt_pmx_get_functions_count,
160	.get_function_name = wmt_pmx_get_function_name,
161	.get_function_groups = wmt_pmx_get_function_groups,
162	.set_mux = wmt_pmx_set_mux,
163	.gpio_disable_free = wmt_pmx_gpio_disable_free,
164	.gpio_set_direction = wmt_pmx_gpio_set_direction,
165};
166
167static int wmt_get_groups_count(struct pinctrl_dev *pctldev)
168{
169	struct wmt_pinctrl_data *data = pinctrl_dev_get_drvdata(pctldev);
170
171	return data->ngroups;
172}
173
174static const char *wmt_get_group_name(struct pinctrl_dev *pctldev,
175				      unsigned selector)
176{
177	struct wmt_pinctrl_data *data = pinctrl_dev_get_drvdata(pctldev);
178
179	return data->groups[selector];
180}
181
182static int wmt_get_group_pins(struct pinctrl_dev *pctldev,
183			      unsigned selector,
184			      const unsigned **pins,
185			      unsigned *num_pins)
186{
187	struct wmt_pinctrl_data *data = pinctrl_dev_get_drvdata(pctldev);
188
189	*pins = &data->pins[selector].number;
190	*num_pins = 1;
191
192	return 0;
193}
194
195static int wmt_pctl_find_group_by_pin(struct wmt_pinctrl_data *data, u32 pin)
196{
197	int i;
198
199	for (i = 0; i < data->npins; i++) {
200		if (data->pins[i].number == pin)
201			return i;
202	}
203
204	return -EINVAL;
205}
206
207static int wmt_pctl_dt_node_to_map_func(struct wmt_pinctrl_data *data,
208					struct device_node *np,
209					u32 pin, u32 fnum,
210					struct pinctrl_map **maps)
211{
212	int group;
213	struct pinctrl_map *map = *maps;
214
215	if (fnum >= ARRAY_SIZE(wmt_functions)) {
216		dev_err(data->dev, "invalid wm,function %d\n", fnum);
217		return -EINVAL;
218	}
219
220	group = wmt_pctl_find_group_by_pin(data, pin);
221	if (group < 0) {
222		dev_err(data->dev, "unable to match pin %d to group\n", pin);
223		return group;
224	}
225
226	map->type = PIN_MAP_TYPE_MUX_GROUP;
227	map->data.mux.group = data->groups[group];
228	map->data.mux.function = wmt_functions[fnum];
229	(*maps)++;
230
231	return 0;
232}
233
234static int wmt_pctl_dt_node_to_map_pull(struct wmt_pinctrl_data *data,
235					struct device_node *np,
236					u32 pin, u32 pull,
237					struct pinctrl_map **maps)
238{
239	int group;
240	unsigned long *configs;
241	struct pinctrl_map *map = *maps;
242
243	if (pull > 2) {
244		dev_err(data->dev, "invalid wm,pull %d\n", pull);
245		return -EINVAL;
246	}
247
248	group = wmt_pctl_find_group_by_pin(data, pin);
249	if (group < 0) {
250		dev_err(data->dev, "unable to match pin %d to group\n", pin);
251		return group;
252	}
253
254	configs = kzalloc(sizeof(*configs), GFP_KERNEL);
255	if (!configs)
256		return -ENOMEM;
257
258	switch (pull) {
259	case 0:
260		configs[0] = PIN_CONFIG_BIAS_DISABLE;
261		break;
262	case 1:
263		configs[0] = PIN_CONFIG_BIAS_PULL_DOWN;
264		break;
265	case 2:
266		configs[0] = PIN_CONFIG_BIAS_PULL_UP;
267		break;
268	default:
269		configs[0] = PIN_CONFIG_BIAS_DISABLE;
270		dev_err(data->dev, "invalid pull state %d - disabling\n", pull);
271	}
272
273	map->type = PIN_MAP_TYPE_CONFIGS_PIN;
274	map->data.configs.group_or_pin = data->groups[group];
275	map->data.configs.configs = configs;
276	map->data.configs.num_configs = 1;
277	(*maps)++;
278
279	return 0;
280}
281
282static void wmt_pctl_dt_free_map(struct pinctrl_dev *pctldev,
283				 struct pinctrl_map *maps,
284				 unsigned num_maps)
285{
286	int i;
287
288	for (i = 0; i < num_maps; i++)
289		if (maps[i].type == PIN_MAP_TYPE_CONFIGS_PIN)
290			kfree(maps[i].data.configs.configs);
291
292	kfree(maps);
293}
294
295static int wmt_pctl_dt_node_to_map(struct pinctrl_dev *pctldev,
296				   struct device_node *np,
297				   struct pinctrl_map **map,
298				   unsigned *num_maps)
299{
300	struct pinctrl_map *maps, *cur_map;
301	struct property *pins, *funcs, *pulls;
302	u32 pin, func, pull;
303	int num_pins, num_funcs, num_pulls, maps_per_pin;
304	int i, err;
305	struct wmt_pinctrl_data *data = pinctrl_dev_get_drvdata(pctldev);
306
307	pins = of_find_property(np, "wm,pins", NULL);
308	if (!pins) {
309		dev_err(data->dev, "missing wmt,pins property\n");
310		return -EINVAL;
311	}
312
313	funcs = of_find_property(np, "wm,function", NULL);
314	pulls = of_find_property(np, "wm,pull", NULL);
315
316	if (!funcs && !pulls) {
317		dev_err(data->dev, "neither wm,function nor wm,pull specified\n");
318		return -EINVAL;
319	}
320
321	/*
322	 * The following lines calculate how many values are defined for each
323	 * of the properties.
324	 */
325	num_pins = pins->length / sizeof(u32);
326	num_funcs = funcs ? (funcs->length / sizeof(u32)) : 0;
327	num_pulls = pulls ? (pulls->length / sizeof(u32)) : 0;
328
329	if (num_funcs > 1 && num_funcs != num_pins) {
330		dev_err(data->dev, "wm,function must have 1 or %d entries\n",
331			num_pins);
332		return -EINVAL;
333	}
334
335	if (num_pulls > 1 && num_pulls != num_pins) {
336		dev_err(data->dev, "wm,pull must have 1 or %d entries\n",
337			num_pins);
338		return -EINVAL;
339	}
340
341	maps_per_pin = 0;
342	if (num_funcs)
343		maps_per_pin++;
344	if (num_pulls)
345		maps_per_pin++;
346
347	cur_map = maps = kcalloc(num_pins * maps_per_pin, sizeof(*maps),
348				 GFP_KERNEL);
349	if (!maps)
350		return -ENOMEM;
351
352	for (i = 0; i < num_pins; i++) {
353		err = of_property_read_u32_index(np, "wm,pins", i, &pin);
354		if (err)
355			goto fail;
356
357		if (pin >= (data->nbanks * 32)) {
358			dev_err(data->dev, "invalid wm,pins value\n");
359			err = -EINVAL;
360			goto fail;
361		}
362
363		if (num_funcs) {
364			err = of_property_read_u32_index(np, "wm,function",
365						(num_funcs > 1 ? i : 0), &func);
366			if (err)
367				goto fail;
368
369			err = wmt_pctl_dt_node_to_map_func(data, np, pin, func,
370							   &cur_map);
371			if (err)
372				goto fail;
373		}
374
375		if (num_pulls) {
376			err = of_property_read_u32_index(np, "wm,pull",
377						(num_pulls > 1 ? i : 0), &pull);
378			if (err)
379				goto fail;
380
381			err = wmt_pctl_dt_node_to_map_pull(data, np, pin, pull,
382							   &cur_map);
383			if (err)
384				goto fail;
385		}
386	}
387	*map = maps;
388	*num_maps = num_pins * maps_per_pin;
389	return 0;
390
391/*
392 * The fail path removes any maps that have been allocated. The fail path is
393 * only called from code after maps has been kzalloc'd. It is also safe to
394 * pass 'num_pins * maps_per_pin' as the map count even though we probably
395 * failed before all the mappings were read as all maps are allocated at once,
396 * and configs are only allocated for .type = PIN_MAP_TYPE_CONFIGS_PIN - there
397 * is no failpath where a config can be allocated without .type being set.
398 */
399fail:
400	wmt_pctl_dt_free_map(pctldev, maps, num_pins * maps_per_pin);
401	return err;
402}
403
404static const struct pinctrl_ops wmt_pctl_ops = {
405	.get_groups_count = wmt_get_groups_count,
406	.get_group_name	= wmt_get_group_name,
407	.get_group_pins	= wmt_get_group_pins,
408	.dt_node_to_map = wmt_pctl_dt_node_to_map,
409	.dt_free_map = wmt_pctl_dt_free_map,
410};
411
412static int wmt_pinconf_get(struct pinctrl_dev *pctldev, unsigned pin,
413			   unsigned long *config)
414{
415	return -ENOTSUPP;
416}
417
418static int wmt_pinconf_set(struct pinctrl_dev *pctldev, unsigned pin,
419			   unsigned long *configs, unsigned num_configs)
420{
421	struct wmt_pinctrl_data *data = pinctrl_dev_get_drvdata(pctldev);
422	enum pin_config_param param;
423	u32 arg;
424	u32 bank = WMT_BANK_FROM_PIN(pin);
425	u32 bit = WMT_BIT_FROM_PIN(pin);
426	u32 reg_pull_en = data->banks[bank].reg_pull_en;
427	u32 reg_pull_cfg = data->banks[bank].reg_pull_cfg;
428	int i;
429
430	if ((reg_pull_en == NO_REG) || (reg_pull_cfg == NO_REG)) {
431		dev_err(data->dev, "bias functions not supported on pin %d\n",
432			pin);
433		return -EINVAL;
434	}
435
436	for (i = 0; i < num_configs; i++) {
437		param = pinconf_to_config_param(configs[i]);
438		arg = pinconf_to_config_argument(configs[i]);
439
440		if ((param == PIN_CONFIG_BIAS_PULL_DOWN) ||
441		    (param == PIN_CONFIG_BIAS_PULL_UP)) {
442			if (arg == 0)
443				param = PIN_CONFIG_BIAS_DISABLE;
444		}
445
446		switch (param) {
447		case PIN_CONFIG_BIAS_DISABLE:
448			wmt_clearbits(data, reg_pull_en, BIT(bit));
449			break;
450		case PIN_CONFIG_BIAS_PULL_DOWN:
451			wmt_clearbits(data, reg_pull_cfg, BIT(bit));
452			wmt_setbits(data, reg_pull_en, BIT(bit));
453			break;
454		case PIN_CONFIG_BIAS_PULL_UP:
455			wmt_setbits(data, reg_pull_cfg, BIT(bit));
456			wmt_setbits(data, reg_pull_en, BIT(bit));
457			break;
458		default:
459			dev_err(data->dev, "unknown pinconf param\n");
460			return -EINVAL;
461		}
462	} /* for each config */
463
464	return 0;
465}
466
467static const struct pinconf_ops wmt_pinconf_ops = {
468	.pin_config_get = wmt_pinconf_get,
469	.pin_config_set = wmt_pinconf_set,
470};
471
472static struct pinctrl_desc wmt_desc = {
473	.owner = THIS_MODULE,
474	.name = "pinctrl-wmt",
475	.pctlops = &wmt_pctl_ops,
476	.pmxops = &wmt_pinmux_ops,
477	.confops = &wmt_pinconf_ops,
478};
479
480static int wmt_gpio_get_direction(struct gpio_chip *chip, unsigned offset)
481{
482	struct wmt_pinctrl_data *data = gpiochip_get_data(chip);
483	u32 bank = WMT_BANK_FROM_PIN(offset);
484	u32 bit = WMT_BIT_FROM_PIN(offset);
485	u32 reg_dir = data->banks[bank].reg_dir;
486	u32 val;
487
488	val = readl_relaxed(data->base + reg_dir);
489	if (val & BIT(bit))
490		return GPIO_LINE_DIRECTION_OUT;
491
492	return GPIO_LINE_DIRECTION_IN;
493}
494
495static int wmt_gpio_get_value(struct gpio_chip *chip, unsigned offset)
496{
497	struct wmt_pinctrl_data *data = gpiochip_get_data(chip);
498	u32 bank = WMT_BANK_FROM_PIN(offset);
499	u32 bit = WMT_BIT_FROM_PIN(offset);
500	u32 reg_data_in = data->banks[bank].reg_data_in;
501
502	if (reg_data_in == NO_REG) {
503		dev_err(data->dev, "no data in register defined\n");
504		return -EINVAL;
505	}
506
507	return !!(readl_relaxed(data->base + reg_data_in) & BIT(bit));
508}
509
510static void wmt_gpio_set_value(struct gpio_chip *chip, unsigned offset,
511			       int val)
512{
513	struct wmt_pinctrl_data *data = gpiochip_get_data(chip);
514	u32 bank = WMT_BANK_FROM_PIN(offset);
515	u32 bit = WMT_BIT_FROM_PIN(offset);
516	u32 reg_data_out = data->banks[bank].reg_data_out;
517
518	if (reg_data_out == NO_REG) {
519		dev_err(data->dev, "no data out register defined\n");
520		return;
521	}
522
523	if (val)
524		wmt_setbits(data, reg_data_out, BIT(bit));
525	else
526		wmt_clearbits(data, reg_data_out, BIT(bit));
527}
528
529static int wmt_gpio_direction_output(struct gpio_chip *chip, unsigned offset,
530				     int value)
531{
532	wmt_gpio_set_value(chip, offset, value);
533	return pinctrl_gpio_direction_output(chip, offset);
534}
535
536static const struct gpio_chip wmt_gpio_chip = {
537	.label = "gpio-wmt",
538	.owner = THIS_MODULE,
539	.request = gpiochip_generic_request,
540	.free = gpiochip_generic_free,
541	.get_direction = wmt_gpio_get_direction,
542	.direction_input = pinctrl_gpio_direction_input,
543	.direction_output = wmt_gpio_direction_output,
544	.get = wmt_gpio_get_value,
545	.set = wmt_gpio_set_value,
546	.can_sleep = false,
547};
548
549int wmt_pinctrl_probe(struct platform_device *pdev,
550		      struct wmt_pinctrl_data *data)
551{
552	int err;
553
554	data->base = devm_platform_ioremap_resource(pdev, 0);
555	if (IS_ERR(data->base))
556		return PTR_ERR(data->base);
557
558	wmt_desc.pins = data->pins;
559	wmt_desc.npins = data->npins;
560
561	data->gpio_chip = wmt_gpio_chip;
562	data->gpio_chip.parent = &pdev->dev;
563	data->gpio_chip.ngpio = data->nbanks * 32;
564
565	platform_set_drvdata(pdev, data);
566
567	data->dev = &pdev->dev;
568
569	data->pctl_dev = devm_pinctrl_register(&pdev->dev, &wmt_desc, data);
570	if (IS_ERR(data->pctl_dev)) {
571		dev_err(&pdev->dev, "Failed to register pinctrl\n");
572		return PTR_ERR(data->pctl_dev);
573	}
574
575	err = gpiochip_add_data(&data->gpio_chip, data);
576	if (err) {
577		dev_err(&pdev->dev, "could not add GPIO chip\n");
578		return err;
579	}
580
581	err = gpiochip_add_pin_range(&data->gpio_chip, dev_name(data->dev),
582				     0, 0, data->nbanks * 32);
583	if (err)
584		goto fail_range;
585
586	dev_info(&pdev->dev, "Pin controller initialized\n");
587
588	return 0;
589
590fail_range:
591	gpiochip_remove(&data->gpio_chip);
592	return err;
593}
594