xref: /openbmc/linux/drivers/pinctrl/pinconf.c (revision 63dc02bd) 
1 /*
2  * Core driver for the pin config portions of the pin control subsystem
3  *
4  * Copyright (C) 2011 ST-Ericsson SA
5  * Written on behalf of Linaro for ST-Ericsson
6  *
7  * Author: Linus Walleij <linus.walleij@linaro.org>
8  *
9  * License terms: GNU General Public License (GPL) version 2
10  */
11 #define pr_fmt(fmt) "pinconfig core: " fmt
12 
13 #include <linux/kernel.h>
14 #include <linux/module.h>
15 #include <linux/init.h>
16 #include <linux/device.h>
17 #include <linux/slab.h>
18 #include <linux/debugfs.h>
19 #include <linux/seq_file.h>
20 #include <linux/pinctrl/machine.h>
21 #include <linux/pinctrl/pinctrl.h>
22 #include <linux/pinctrl/pinconf.h>
23 #include "core.h"
24 #include "pinconf.h"
25 
26 int pinconf_check_ops(struct pinctrl_dev *pctldev)
27 {
28 	const struct pinconf_ops *ops = pctldev->desc->confops;
29 
30 	/* We must be able to read out pin status */
31 	if (!ops->pin_config_get && !ops->pin_config_group_get)
32 		return -EINVAL;
33 	/* We have to be able to config the pins in SOME way */
34 	if (!ops->pin_config_set && !ops->pin_config_group_set)
35 		return -EINVAL;
36 	return 0;
37 }
38 
39 int pinconf_validate_map(struct pinctrl_map const *map, int i)
40 {
41 	if (!map->data.configs.group_or_pin) {
42 		pr_err("failed to register map %s (%d): no group/pin given\n",
43 		       map->name, i);
44 		return -EINVAL;
45 	}
46 
47 	if (map->data.configs.num_configs &&
48 			!map->data.configs.configs) {
49 		pr_err("failed to register map %s (%d): no configs ptr given\n",
50 		       map->name, i);
51 		return -EINVAL;
52 	}
53 
54 	return 0;
55 }
56 
57 int pin_config_get_for_pin(struct pinctrl_dev *pctldev, unsigned pin,
58 			   unsigned long *config)
59 {
60 	const struct pinconf_ops *ops = pctldev->desc->confops;
61 
62 	if (!ops || !ops->pin_config_get) {
63 		dev_err(pctldev->dev, "cannot get pin configuration, missing "
64 			"pin_config_get() function in driver\n");
65 		return -EINVAL;
66 	}
67 
68 	return ops->pin_config_get(pctldev, pin, config);
69 }
70 
71 /**
72  * pin_config_get() - get the configuration of a single pin parameter
73  * @dev_name: name of the pin controller device for this pin
74  * @name: name of the pin to get the config for
75  * @config: the config pointed to by this argument will be filled in with the
76  *	current pin state, it can be used directly by drivers as a numeral, or
77  *	it can be dereferenced to any struct.
78  */
79 int pin_config_get(const char *dev_name, const char *name,
80 			  unsigned long *config)
81 {
82 	struct pinctrl_dev *pctldev;
83 	int pin;
84 
85 	mutex_lock(&pinctrl_mutex);
86 
87 	pctldev = get_pinctrl_dev_from_devname(dev_name);
88 	if (!pctldev) {
89 		pin = -EINVAL;
90 		goto unlock;
91 	}
92 
93 	pin = pin_get_from_name(pctldev, name);
94 	if (pin < 0)
95 		goto unlock;
96 
97 	pin = pin_config_get_for_pin(pctldev, pin, config);
98 
99 unlock:
100 	mutex_unlock(&pinctrl_mutex);
101 	return pin;
102 }
103 EXPORT_SYMBOL(pin_config_get);
104 
105 static int pin_config_set_for_pin(struct pinctrl_dev *pctldev, unsigned pin,
106 			   unsigned long config)
107 {
108 	const struct pinconf_ops *ops = pctldev->desc->confops;
109 	int ret;
110 
111 	if (!ops || !ops->pin_config_set) {
112 		dev_err(pctldev->dev, "cannot configure pin, missing "
113 			"config function in driver\n");
114 		return -EINVAL;
115 	}
116 
117 	ret = ops->pin_config_set(pctldev, pin, config);
118 	if (ret) {
119 		dev_err(pctldev->dev,
120 			"unable to set pin configuration on pin %d\n", pin);
121 		return ret;
122 	}
123 
124 	return 0;
125 }
126 
127 /**
128  * pin_config_set() - set the configuration of a single pin parameter
129  * @dev_name: name of pin controller device for this pin
130  * @name: name of the pin to set the config for
131  * @config: the config in this argument will contain the desired pin state, it
132  *	can be used directly by drivers as a numeral, or it can be dereferenced
133  *	to any struct.
134  */
135 int pin_config_set(const char *dev_name, const char *name,
136 		   unsigned long config)
137 {
138 	struct pinctrl_dev *pctldev;
139 	int pin, ret;
140 
141 	mutex_lock(&pinctrl_mutex);
142 
143 	pctldev = get_pinctrl_dev_from_devname(dev_name);
144 	if (!pctldev) {
145 		ret = -EINVAL;
146 		goto unlock;
147 	}
148 
149 	pin = pin_get_from_name(pctldev, name);
150 	if (pin < 0) {
151 		ret = pin;
152 		goto unlock;
153 	}
154 
155 	ret = pin_config_set_for_pin(pctldev, pin, config);
156 
157 unlock:
158 	mutex_unlock(&pinctrl_mutex);
159 	return ret;
160 }
161 EXPORT_SYMBOL(pin_config_set);
162 
163 int pin_config_group_get(const char *dev_name, const char *pin_group,
164 			 unsigned long *config)
165 {
166 	struct pinctrl_dev *pctldev;
167 	const struct pinconf_ops *ops;
168 	int selector, ret;
169 
170 	mutex_lock(&pinctrl_mutex);
171 
172 	pctldev = get_pinctrl_dev_from_devname(dev_name);
173 	if (!pctldev) {
174 		ret = -EINVAL;
175 		goto unlock;
176 	}
177 	ops = pctldev->desc->confops;
178 
179 	if (!ops || !ops->pin_config_group_get) {
180 		dev_err(pctldev->dev, "cannot get configuration for pin "
181 			"group, missing group config get function in "
182 			"driver\n");
183 		ret = -EINVAL;
184 		goto unlock;
185 	}
186 
187 	selector = pinctrl_get_group_selector(pctldev, pin_group);
188 	if (selector < 0) {
189 		ret = selector;
190 		goto unlock;
191 	}
192 
193 	ret = ops->pin_config_group_get(pctldev, selector, config);
194 
195 unlock:
196 	mutex_unlock(&pinctrl_mutex);
197 	return ret;
198 }
199 EXPORT_SYMBOL(pin_config_group_get);
200 
201 int pin_config_group_set(const char *dev_name, const char *pin_group,
202 			 unsigned long config)
203 {
204 	struct pinctrl_dev *pctldev;
205 	const struct pinconf_ops *ops;
206 	const struct pinctrl_ops *pctlops;
207 	int selector;
208 	const unsigned *pins;
209 	unsigned num_pins;
210 	int ret;
211 	int i;
212 
213 	mutex_lock(&pinctrl_mutex);
214 
215 	pctldev = get_pinctrl_dev_from_devname(dev_name);
216 	if (!pctldev) {
217 		ret = -EINVAL;
218 		goto unlock;
219 	}
220 	ops = pctldev->desc->confops;
221 	pctlops = pctldev->desc->pctlops;
222 
223 	if (!ops || (!ops->pin_config_group_set && !ops->pin_config_set)) {
224 		dev_err(pctldev->dev, "cannot configure pin group, missing "
225 			"config function in driver\n");
226 		ret = -EINVAL;
227 		goto unlock;
228 	}
229 
230 	selector = pinctrl_get_group_selector(pctldev, pin_group);
231 	if (selector < 0) {
232 		ret = selector;
233 		goto unlock;
234 	}
235 
236 	ret = pctlops->get_group_pins(pctldev, selector, &pins, &num_pins);
237 	if (ret) {
238 		dev_err(pctldev->dev, "cannot configure pin group, error "
239 			"getting pins\n");
240 		goto unlock;
241 	}
242 
243 	/*
244 	 * If the pin controller supports handling entire groups we use that
245 	 * capability.
246 	 */
247 	if (ops->pin_config_group_set) {
248 		ret = ops->pin_config_group_set(pctldev, selector, config);
249 		/*
250 		 * If the pin controller prefer that a certain group be handled
251 		 * pin-by-pin as well, it returns -EAGAIN.
252 		 */
253 		if (ret != -EAGAIN)
254 			goto unlock;
255 	}
256 
257 	/*
258 	 * If the controller cannot handle entire groups, we configure each pin
259 	 * individually.
260 	 */
261 	if (!ops->pin_config_set) {
262 		ret = 0;
263 		goto unlock;
264 	}
265 
266 	for (i = 0; i < num_pins; i++) {
267 		ret = ops->pin_config_set(pctldev, pins[i], config);
268 		if (ret < 0)
269 			goto unlock;
270 	}
271 
272 	ret = 0;
273 
274 unlock:
275 	mutex_unlock(&pinctrl_mutex);
276 
277 	return ret;
278 }
279 EXPORT_SYMBOL(pin_config_group_set);
280 
281 int pinconf_map_to_setting(struct pinctrl_map const *map,
282 			  struct pinctrl_setting *setting)
283 {
284 	struct pinctrl_dev *pctldev = setting->pctldev;
285 	int pin;
286 
287 	switch (setting->type) {
288 	case PIN_MAP_TYPE_CONFIGS_PIN:
289 		pin = pin_get_from_name(pctldev,
290 					map->data.configs.group_or_pin);
291 		if (pin < 0) {
292 			dev_err(pctldev->dev, "could not map pin config for \"%s\"",
293 				map->data.configs.group_or_pin);
294 			return pin;
295 		}
296 		setting->data.configs.group_or_pin = pin;
297 		break;
298 	case PIN_MAP_TYPE_CONFIGS_GROUP:
299 		pin = pinctrl_get_group_selector(pctldev,
300 					 map->data.configs.group_or_pin);
301 		if (pin < 0) {
302 			dev_err(pctldev->dev, "could not map group config for \"%s\"",
303 				map->data.configs.group_or_pin);
304 			return pin;
305 		}
306 		setting->data.configs.group_or_pin = pin;
307 		break;
308 	default:
309 		return -EINVAL;
310 	}
311 
312 	setting->data.configs.num_configs = map->data.configs.num_configs;
313 	setting->data.configs.configs = map->data.configs.configs;
314 
315 	return 0;
316 }
317 
318 void pinconf_free_setting(struct pinctrl_setting const *setting)
319 {
320 }
321 
322 int pinconf_apply_setting(struct pinctrl_setting const *setting)
323 {
324 	struct pinctrl_dev *pctldev = setting->pctldev;
325 	const struct pinconf_ops *ops = pctldev->desc->confops;
326 	int i, ret;
327 
328 	if (!ops) {
329 		dev_err(pctldev->dev, "missing confops\n");
330 		return -EINVAL;
331 	}
332 
333 	switch (setting->type) {
334 	case PIN_MAP_TYPE_CONFIGS_PIN:
335 		if (!ops->pin_config_set) {
336 			dev_err(pctldev->dev, "missing pin_config_set op\n");
337 			return -EINVAL;
338 		}
339 		for (i = 0; i < setting->data.configs.num_configs; i++) {
340 			ret = ops->pin_config_set(pctldev,
341 					setting->data.configs.group_or_pin,
342 					setting->data.configs.configs[i]);
343 			if (ret < 0) {
344 				dev_err(pctldev->dev,
345 					"pin_config_set op failed for pin %d config %08lx\n",
346 					setting->data.configs.group_or_pin,
347 					setting->data.configs.configs[i]);
348 				return ret;
349 			}
350 		}
351 		break;
352 	case PIN_MAP_TYPE_CONFIGS_GROUP:
353 		if (!ops->pin_config_group_set) {
354 			dev_err(pctldev->dev,
355 				"missing pin_config_group_set op\n");
356 			return -EINVAL;
357 		}
358 		for (i = 0; i < setting->data.configs.num_configs; i++) {
359 			ret = ops->pin_config_group_set(pctldev,
360 					setting->data.configs.group_or_pin,
361 					setting->data.configs.configs[i]);
362 			if (ret < 0) {
363 				dev_err(pctldev->dev,
364 					"pin_config_group_set op failed for group %d config %08lx\n",
365 					setting->data.configs.group_or_pin,
366 					setting->data.configs.configs[i]);
367 				return ret;
368 			}
369 		}
370 		break;
371 	default:
372 		return -EINVAL;
373 	}
374 
375 	return 0;
376 }
377 
378 #ifdef CONFIG_DEBUG_FS
379 
380 void pinconf_show_map(struct seq_file *s, struct pinctrl_map const *map)
381 {
382 	int i;
383 
384 	switch (map->type) {
385 	case PIN_MAP_TYPE_CONFIGS_PIN:
386 		seq_printf(s, "pin ");
387 		break;
388 	case PIN_MAP_TYPE_CONFIGS_GROUP:
389 		seq_printf(s, "group ");
390 		break;
391 	default:
392 		break;
393 	}
394 
395 	seq_printf(s, "%s\n", map->data.configs.group_or_pin);
396 
397 	for (i = 0; i < map->data.configs.num_configs; i++)
398 		seq_printf(s, "config %08lx\n", map->data.configs.configs[i]);
399 }
400 
401 void pinconf_show_setting(struct seq_file *s,
402 			  struct pinctrl_setting const *setting)
403 {
404 	struct pinctrl_dev *pctldev = setting->pctldev;
405 	const struct pinctrl_ops *pctlops = pctldev->desc->pctlops;
406 	struct pin_desc *desc;
407 	int i;
408 
409 	switch (setting->type) {
410 	case PIN_MAP_TYPE_CONFIGS_PIN:
411 		desc = pin_desc_get(setting->pctldev,
412 				    setting->data.configs.group_or_pin);
413 		seq_printf(s, "pin %s (%d)",
414 			   desc->name ? desc->name : "unnamed",
415 			   setting->data.configs.group_or_pin);
416 		break;
417 	case PIN_MAP_TYPE_CONFIGS_GROUP:
418 		seq_printf(s, "group %s (%d)",
419 			   pctlops->get_group_name(pctldev,
420 					setting->data.configs.group_or_pin),
421 			   setting->data.configs.group_or_pin);
422 		break;
423 	default:
424 		break;
425 	}
426 
427 	/*
428 	 * FIXME: We should really get the pin controler to dump the config
429 	 * values, so they can be decoded to something meaningful.
430 	 */
431 	for (i = 0; i < setting->data.configs.num_configs; i++)
432 		seq_printf(s, " %08lx", setting->data.configs.configs[i]);
433 
434 	seq_printf(s, "\n");
435 }
436 
437 static void pinconf_dump_pin(struct pinctrl_dev *pctldev,
438 			     struct seq_file *s, int pin)
439 {
440 	const struct pinconf_ops *ops = pctldev->desc->confops;
441 
442 	/* no-op when not using generic pin config */
443 	pinconf_generic_dump_pin(pctldev, s, pin);
444 	if (ops && ops->pin_config_dbg_show)
445 		ops->pin_config_dbg_show(pctldev, s, pin);
446 }
447 
448 static int pinconf_pins_show(struct seq_file *s, void *what)
449 {
450 	struct pinctrl_dev *pctldev = s->private;
451 	unsigned i, pin;
452 
453 	seq_puts(s, "Pin config settings per pin\n");
454 	seq_puts(s, "Format: pin (name): pinmux setting array\n");
455 
456 	mutex_lock(&pinctrl_mutex);
457 
458 	/* The pin number can be retrived from the pin controller descriptor */
459 	for (i = 0; i < pctldev->desc->npins; i++) {
460 		struct pin_desc *desc;
461 
462 		pin = pctldev->desc->pins[i].number;
463 		desc = pin_desc_get(pctldev, pin);
464 		/* Skip if we cannot search the pin */
465 		if (desc == NULL)
466 			continue;
467 
468 		seq_printf(s, "pin %d (%s):", pin,
469 			   desc->name ? desc->name : "unnamed");
470 
471 		pinconf_dump_pin(pctldev, s, pin);
472 
473 		seq_printf(s, "\n");
474 	}
475 
476 	mutex_unlock(&pinctrl_mutex);
477 
478 	return 0;
479 }
480 
481 static void pinconf_dump_group(struct pinctrl_dev *pctldev,
482 			       struct seq_file *s, unsigned selector,
483 			       const char *gname)
484 {
485 	const struct pinconf_ops *ops = pctldev->desc->confops;
486 
487 	/* no-op when not using generic pin config */
488 	pinconf_generic_dump_group(pctldev, s, gname);
489 	if (ops && ops->pin_config_group_dbg_show)
490 		ops->pin_config_group_dbg_show(pctldev, s, selector);
491 }
492 
493 static int pinconf_groups_show(struct seq_file *s, void *what)
494 {
495 	struct pinctrl_dev *pctldev = s->private;
496 	const struct pinctrl_ops *pctlops = pctldev->desc->pctlops;
497 	const struct pinconf_ops *ops = pctldev->desc->confops;
498 	unsigned selector = 0;
499 
500 	if (!ops || !ops->pin_config_group_get)
501 		return 0;
502 
503 	seq_puts(s, "Pin config settings per pin group\n");
504 	seq_puts(s, "Format: group (name): pinmux setting array\n");
505 
506 	mutex_lock(&pinctrl_mutex);
507 
508 	while (pctlops->list_groups(pctldev, selector) >= 0) {
509 		const char *gname = pctlops->get_group_name(pctldev, selector);
510 
511 		seq_printf(s, "%u (%s):", selector, gname);
512 		pinconf_dump_group(pctldev, s, selector, gname);
513 		seq_printf(s, "\n");
514 
515 		selector++;
516 	}
517 
518 	mutex_unlock(&pinctrl_mutex);
519 
520 	return 0;
521 }
522 
523 static int pinconf_pins_open(struct inode *inode, struct file *file)
524 {
525 	return single_open(file, pinconf_pins_show, inode->i_private);
526 }
527 
528 static int pinconf_groups_open(struct inode *inode, struct file *file)
529 {
530 	return single_open(file, pinconf_groups_show, inode->i_private);
531 }
532 
533 static const struct file_operations pinconf_pins_ops = {
534 	.open		= pinconf_pins_open,
535 	.read		= seq_read,
536 	.llseek		= seq_lseek,
537 	.release	= single_release,
538 };
539 
540 static const struct file_operations pinconf_groups_ops = {
541 	.open		= pinconf_groups_open,
542 	.read		= seq_read,
543 	.llseek		= seq_lseek,
544 	.release	= single_release,
545 };
546 
547 void pinconf_init_device_debugfs(struct dentry *devroot,
548 			 struct pinctrl_dev *pctldev)
549 {
550 	debugfs_create_file("pinconf-pins", S_IFREG | S_IRUGO,
551 			    devroot, pctldev, &pinconf_pins_ops);
552 	debugfs_create_file("pinconf-groups", S_IFREG | S_IRUGO,
553 			    devroot, pctldev, &pinconf_groups_ops);
554 }
555 
556 #endif
557