pinconf.c 15.8 KB
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621
/*
 * Core driver for the pin config portions of the pin control subsystem
 *
 * Copyright (C) 2011 ST-Ericsson SA
 * Written on behalf of Linaro for ST-Ericsson
 *
 * Author: Linus Walleij <linus.walleij@linaro.org>
 *
 * License terms: GNU General Public License (GPL) version 2
 */
#define pr_fmt(fmt) "pinconfig core: " fmt

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/device.h>
#include <linux/slab.h>
#include <linux/debugfs.h>
#include <linux/seq_file.h>
#include <linux/uaccess.h>
#include <linux/pinctrl/machine.h>
#include <linux/pinctrl/pinctrl.h>
#include <linux/pinctrl/pinconf.h>
#include "core.h"
#include "pinconf.h"

int pinconf_check_ops(struct pinctrl_dev *pctldev)
{
	const struct pinconf_ops *ops = pctldev->desc->confops;

	/* We have to be able to config the pins in SOME way */
	if (!ops->pin_config_set && !ops->pin_config_group_set) {
		dev_err(pctldev->dev,
			"pinconf has to be able to set a pins config\n");
		return -EINVAL;
	}
	return 0;
}

int pinconf_validate_map(struct pinctrl_map const *map, int i)
{
	if (!map->data.configs.group_or_pin) {
		pr_err("failed to register map %s (%d): no group/pin given\n",
		       map->name, i);
		return -EINVAL;
	}

	if (!map->data.configs.num_configs ||
			!map->data.configs.configs) {
		pr_err("failed to register map %s (%d): no configs given\n",
		       map->name, i);
		return -EINVAL;
	}

	return 0;
}

int pin_config_get_for_pin(struct pinctrl_dev *pctldev, unsigned pin,
			   unsigned long *config)
{
	const struct pinconf_ops *ops = pctldev->desc->confops;

	if (!ops || !ops->pin_config_get) {
		dev_dbg(pctldev->dev, "cannot get pin configuration, missing "
			"pin_config_get() function in driver\n");
		return -ENOTSUPP;
	}

	return ops->pin_config_get(pctldev, pin, config);
}

int pin_config_group_get(const char *dev_name, const char *pin_group,
			 unsigned long *config)
{
	struct pinctrl_dev *pctldev;
	const struct pinconf_ops *ops;
	int selector, ret;

	pctldev = get_pinctrl_dev_from_devname(dev_name);
	if (!pctldev) {
		ret = -EINVAL;
		return ret;
	}

	mutex_lock(&pctldev->mutex);

	ops = pctldev->desc->confops;

	if (!ops || !ops->pin_config_group_get) {
		dev_dbg(pctldev->dev, "cannot get configuration for pin "
			"group, missing group config get function in "
			"driver\n");
		ret = -ENOTSUPP;
		goto unlock;
	}

	selector = pinctrl_get_group_selector(pctldev, pin_group);
	if (selector < 0) {
		ret = selector;
		goto unlock;
	}

	ret = ops->pin_config_group_get(pctldev, selector, config);

unlock:
	mutex_unlock(&pctldev->mutex);
	return ret;
}

int pinconf_map_to_setting(struct pinctrl_map const *map,
			  struct pinctrl_setting *setting)
{
	struct pinctrl_dev *pctldev = setting->pctldev;
	int pin;

	switch (setting->type) {
	case PIN_MAP_TYPE_CONFIGS_PIN:
		pin = pin_get_from_name(pctldev,
					map->data.configs.group_or_pin);
		if (pin < 0) {
			dev_err(pctldev->dev, "could not map pin config for \"%s\"",
				map->data.configs.group_or_pin);
			return pin;
		}
		setting->data.configs.group_or_pin = pin;
		break;
	case PIN_MAP_TYPE_CONFIGS_GROUP:
		pin = pinctrl_get_group_selector(pctldev,
					 map->data.configs.group_or_pin);
		if (pin < 0) {
			dev_err(pctldev->dev, "could not map group config for \"%s\"",
				map->data.configs.group_or_pin);
			return pin;
		}
		setting->data.configs.group_or_pin = pin;
		break;
	default:
		return -EINVAL;
	}

	setting->data.configs.num_configs = map->data.configs.num_configs;
	setting->data.configs.configs = map->data.configs.configs;

	return 0;
}

void pinconf_free_setting(struct pinctrl_setting const *setting)
{
}

int pinconf_apply_setting(struct pinctrl_setting const *setting)
{
	struct pinctrl_dev *pctldev = setting->pctldev;
	const struct pinconf_ops *ops = pctldev->desc->confops;
	int ret;

	if (!ops) {
		dev_err(pctldev->dev, "missing confops\n");
		return -EINVAL;
	}

	switch (setting->type) {
	case PIN_MAP_TYPE_CONFIGS_PIN:
		if (!ops->pin_config_set) {
			dev_err(pctldev->dev, "missing pin_config_set op\n");
			return -EINVAL;
		}
		ret = ops->pin_config_set(pctldev,
				setting->data.configs.group_or_pin,
				setting->data.configs.configs,
				setting->data.configs.num_configs);
		if (ret < 0) {
			dev_err(pctldev->dev,
				"pin_config_set op failed for pin %d\n",
				setting->data.configs.group_or_pin);
			return ret;
		}
		break;
	case PIN_MAP_TYPE_CONFIGS_GROUP:
		if (!ops->pin_config_group_set) {
			dev_err(pctldev->dev,
				"missing pin_config_group_set op\n");
			return -EINVAL;
		}
		ret = ops->pin_config_group_set(pctldev,
				setting->data.configs.group_or_pin,
				setting->data.configs.configs,
				setting->data.configs.num_configs);
		if (ret < 0) {
			dev_err(pctldev->dev,
				"pin_config_group_set op failed for group %d\n",
				setting->data.configs.group_or_pin);
			return ret;
		}
		break;
	default:
		return -EINVAL;
	}

	return 0;
}

#ifdef CONFIG_DEBUG_FS

void pinconf_show_map(struct seq_file *s, struct pinctrl_map const *map)
{
	struct pinctrl_dev *pctldev;
	const struct pinconf_ops *confops;
	int i;

	pctldev = get_pinctrl_dev_from_devname(map->ctrl_dev_name);
	if (pctldev)
		confops = pctldev->desc->confops;
	else
		confops = NULL;

	switch (map->type) {
	case PIN_MAP_TYPE_CONFIGS_PIN:
		seq_printf(s, "pin ");
		break;
	case PIN_MAP_TYPE_CONFIGS_GROUP:
		seq_printf(s, "group ");
		break;
	default:
		break;
	}

	seq_printf(s, "%s\n", map->data.configs.group_or_pin);

	for (i = 0; i < map->data.configs.num_configs; i++) {
		seq_printf(s, "config ");
		if (confops && confops->pin_config_config_dbg_show)
			confops->pin_config_config_dbg_show(pctldev, s,
						map->data.configs.configs[i]);
		else
			seq_printf(s, "%08lx", map->data.configs.configs[i]);
		seq_printf(s, "\n");
	}
}

void pinconf_show_setting(struct seq_file *s,
			  struct pinctrl_setting const *setting)
{
	struct pinctrl_dev *pctldev = setting->pctldev;
	const struct pinctrl_ops *pctlops = pctldev->desc->pctlops;
	const struct pinconf_ops *confops = pctldev->desc->confops;
	struct pin_desc *desc;
	int i;

	switch (setting->type) {
	case PIN_MAP_TYPE_CONFIGS_PIN:
		desc = pin_desc_get(setting->pctldev,
				    setting->data.configs.group_or_pin);
		seq_printf(s, "pin %s (%d)",
			   desc->name ? desc->name : "unnamed",
			   setting->data.configs.group_or_pin);
		break;
	case PIN_MAP_TYPE_CONFIGS_GROUP:
		seq_printf(s, "group %s (%d)",
			   pctlops->get_group_name(pctldev,
					setting->data.configs.group_or_pin),
			   setting->data.configs.group_or_pin);
		break;
	default:
		break;
	}

	/*
	 * FIXME: We should really get the pin controler to dump the config
	 * values, so they can be decoded to something meaningful.
	 */
	for (i = 0; i < setting->data.configs.num_configs; i++) {
		seq_printf(s, " ");
		if (confops && confops->pin_config_config_dbg_show)
			confops->pin_config_config_dbg_show(pctldev, s,
				setting->data.configs.configs[i]);
		else
			seq_printf(s, "%08lx",
				   setting->data.configs.configs[i]);
	}

	seq_printf(s, "\n");
}

static void pinconf_dump_pin(struct pinctrl_dev *pctldev,
			     struct seq_file *s, int pin)
{
	const struct pinconf_ops *ops = pctldev->desc->confops;

	/* no-op when not using generic pin config */
	pinconf_generic_dump_pin(pctldev, s, pin);
	if (ops && ops->pin_config_dbg_show)
		ops->pin_config_dbg_show(pctldev, s, pin);
}

static int pinconf_pins_show(struct seq_file *s, void *what)
{
	struct pinctrl_dev *pctldev = s->private;
	unsigned i, pin;

	seq_puts(s, "Pin config settings per pin\n");
	seq_puts(s, "Format: pin (name): configs\n");

	mutex_lock(&pctldev->mutex);

	/* The pin number can be retrived from the pin controller descriptor */
	for (i = 0; i < pctldev->desc->npins; i++) {
		struct pin_desc *desc;

		pin = pctldev->desc->pins[i].number;
		desc = pin_desc_get(pctldev, pin);
		/* Skip if we cannot search the pin */
		if (desc == NULL)
			continue;

		seq_printf(s, "pin %d (%s):", pin,
			   desc->name ? desc->name : "unnamed");

		pinconf_dump_pin(pctldev, s, pin);

		seq_printf(s, "\n");
	}

	mutex_unlock(&pctldev->mutex);

	return 0;
}

static void pinconf_dump_group(struct pinctrl_dev *pctldev,
			       struct seq_file *s, unsigned selector,
			       const char *gname)
{
	const struct pinconf_ops *ops = pctldev->desc->confops;

	/* no-op when not using generic pin config */
	pinconf_generic_dump_group(pctldev, s, gname);
	if (ops && ops->pin_config_group_dbg_show)
		ops->pin_config_group_dbg_show(pctldev, s, selector);
}

static int pinconf_groups_show(struct seq_file *s, void *what)
{
	struct pinctrl_dev *pctldev = s->private;
	const struct pinctrl_ops *pctlops = pctldev->desc->pctlops;
	unsigned ngroups = pctlops->get_groups_count(pctldev);
	unsigned selector = 0;

	seq_puts(s, "Pin config settings per pin group\n");
	seq_puts(s, "Format: group (name): configs\n");

	while (selector < ngroups) {
		const char *gname = pctlops->get_group_name(pctldev, selector);

		seq_printf(s, "%u (%s):", selector, gname);
		pinconf_dump_group(pctldev, s, selector, gname);
		seq_printf(s, "\n");

		selector++;
	}

	return 0;
}

static int pinconf_pins_open(struct inode *inode, struct file *file)
{
	return single_open(file, pinconf_pins_show, inode->i_private);
}

static int pinconf_groups_open(struct inode *inode, struct file *file)
{
	return single_open(file, pinconf_groups_show, inode->i_private);
}

static const struct file_operations pinconf_pins_ops = {
	.open		= pinconf_pins_open,
	.read		= seq_read,
	.llseek		= seq_lseek,
	.release	= single_release,
};

static const struct file_operations pinconf_groups_ops = {
	.open		= pinconf_groups_open,
	.read		= seq_read,
	.llseek		= seq_lseek,
	.release	= single_release,
};

#define MAX_NAME_LEN 15

struct dbg_cfg {
	enum pinctrl_map_type map_type;
	char dev_name[MAX_NAME_LEN+1];
	char state_name[MAX_NAME_LEN+1];
	char pin_name[MAX_NAME_LEN+1];
};

/*
 * Goal is to keep this structure as global in order to simply read the
 * pinconf-config file after a write to check config is as expected
 */
static struct dbg_cfg pinconf_dbg_conf;

/**
 * pinconf_dbg_config_print() - display the pinctrl config from the pinctrl
 * map, of the dev/pin/state that was last written to pinconf-config file.
 * @s: string filled in  with config description
 * @d: not used
 */
static int pinconf_dbg_config_print(struct seq_file *s, void *d)
{
	struct pinctrl_maps *maps_node;
	const struct pinctrl_map *map;
	const struct pinctrl_map *found = NULL;
	struct pinctrl_dev *pctldev;
	const struct pinconf_ops *confops = NULL;
	struct dbg_cfg *dbg = &pinconf_dbg_conf;
	int i, j;
	unsigned long config;

	mutex_lock(&pinctrl_maps_mutex);

	/* Parse the pinctrl map and look for the elected pin/state */
	for_each_maps(maps_node, i, map) {
		if (map->type != dbg->map_type)
			continue;
		if (strcmp(map->dev_name, dbg->dev_name))
			continue;
		if (strcmp(map->name, dbg->state_name))
			continue;

		for (j = 0; j < map->data.configs.num_configs; j++) {
			if (!strcmp(map->data.configs.group_or_pin,
					dbg->pin_name)) {
				/* We found the right pin / state */
				found = map;
				break;
			}
		}
	}

	if (!found) {
		seq_printf(s, "No config found for dev/state/pin, expected:\n");
		seq_printf(s, "Searched dev:%s\n", dbg->dev_name);
		seq_printf(s, "Searched state:%s\n", dbg->state_name);
		seq_printf(s, "Searched pin:%s\n", dbg->pin_name);
		seq_printf(s, "Use: modify config_pin <devname> "\
				"<state> <pinname> <value>\n");
		goto exit;
	}

	pctldev = get_pinctrl_dev_from_devname(found->ctrl_dev_name);
	config = *found->data.configs.configs;
	seq_printf(s, "Dev %s has config of %s in state %s: 0x%08lX\n",
			dbg->dev_name, dbg->pin_name,
			dbg->state_name, config);

	if (pctldev)
		confops = pctldev->desc->confops;

	if (confops && confops->pin_config_config_dbg_show)
		confops->pin_config_config_dbg_show(pctldev, s, config);

exit:
	mutex_unlock(&pinctrl_maps_mutex);

	return 0;
}

/**
 * pinconf_dbg_config_write() - modify the pinctrl config in the pinctrl
 * map, of a dev/pin/state entry based on user entries to pinconf-config
 * @user_buf: contains the modification request with expected format:
 *     modify config_pin <devicename> <state> <pinname> <newvalue>
 * modify is literal string, alternatives like add/delete not supported yet
 * config_pin is literal, alternatives like config_mux not supported yet
 * <devicename> <state> <pinname> are values that should match the pinctrl-maps
 * <newvalue> reflects the new config and is driver dependant
 */
static ssize_t pinconf_dbg_config_write(struct file *file,
	const char __user *user_buf, size_t count, loff_t *ppos)
{
	struct pinctrl_maps *maps_node;
	const struct pinctrl_map *map;
	const struct pinctrl_map *found = NULL;
	struct pinctrl_dev *pctldev;
	const struct pinconf_ops *confops = NULL;
	struct dbg_cfg *dbg = &pinconf_dbg_conf;
	const struct pinctrl_map_configs *configs;
	char config[MAX_NAME_LEN+1];
	char buf[128];
	char *b = &buf[0];
	int buf_size;
	char *token;
	int i;

	/* Get userspace string and assure termination */
	buf_size = min(count, sizeof(buf) - 1);
	if (copy_from_user(buf, user_buf, buf_size))
		return -EFAULT;
	buf[buf_size] = 0;

	/*
	 * need to parse entry and extract parameters:
	 * modify configs_pin devicename state pinname newvalue
	 */

	/* Get arg: 'modify' */
	token = strsep(&b, " ");
	if (!token)
		return -EINVAL;
	if (strcmp(token, "modify"))
		return -EINVAL;

	/* Get arg type: "config_pin" type supported so far */
	token = strsep(&b, " ");
	if (!token)
		return -EINVAL;
	if (strcmp(token, "config_pin"))
		return -EINVAL;
	dbg->map_type = PIN_MAP_TYPE_CONFIGS_PIN;

	/* get arg 'device_name' */
	token = strsep(&b, " ");
	if (token == NULL)
		return -EINVAL;
	if (strlen(token) >= MAX_NAME_LEN)
		return -EINVAL;
	strncpy(dbg->dev_name, token, MAX_NAME_LEN);

	/* get arg 'state_name' */
	token = strsep(&b, " ");
	if (token == NULL)
		return -EINVAL;
	if (strlen(token) >= MAX_NAME_LEN)
		return -EINVAL;
	strncpy(dbg->state_name, token, MAX_NAME_LEN);

	/* get arg 'pin_name' */
	token = strsep(&b, " ");
	if (token == NULL)
		return -EINVAL;
	if (strlen(token) >= MAX_NAME_LEN)
		return -EINVAL;
	strncpy(dbg->pin_name, token, MAX_NAME_LEN);

	/* get new_value of config' */
	token = strsep(&b, " ");
	if (token == NULL)
		return -EINVAL;
	if (strlen(token) >= MAX_NAME_LEN)
		return -EINVAL;
	strncpy(config, token, MAX_NAME_LEN);

	mutex_lock(&pinctrl_maps_mutex);

	/* Parse the pinctrl map and look for the selected dev/state/pin */
	for_each_maps(maps_node, i, map) {
		if (strcmp(map->dev_name, dbg->dev_name))
			continue;
		if (map->type != dbg->map_type)
			continue;
		if (strcmp(map->name, dbg->state_name))
			continue;

		/*  we found the right pin / state, so overwrite config */
		if (!strcmp(map->data.configs.group_or_pin, dbg->pin_name)) {
			found = map;
			break;
		}
	}

	if (!found) {
		count = -EINVAL;
		goto exit;
	}

	pctldev = get_pinctrl_dev_from_devname(found->ctrl_dev_name);
	if (pctldev)
		confops = pctldev->desc->confops;

	if (confops && confops->pin_config_dbg_parse_modify) {
		configs = &found->data.configs;
		for (i = 0; i < configs->num_configs; i++) {
			confops->pin_config_dbg_parse_modify(pctldev,
						     config,
						     &configs->configs[i]);
		}
	}

exit:
	mutex_unlock(&pinctrl_maps_mutex);

	return count;
}

static int pinconf_dbg_config_open(struct inode *inode, struct file *file)
{
	return single_open(file, pinconf_dbg_config_print, inode->i_private);
}

static const struct file_operations pinconf_dbg_pinconfig_fops = {
	.open = pinconf_dbg_config_open,
	.write = pinconf_dbg_config_write,
	.read = seq_read,
	.llseek = seq_lseek,
	.release = single_release,
	.owner = THIS_MODULE,
};

void pinconf_init_device_debugfs(struct dentry *devroot,
			 struct pinctrl_dev *pctldev)
{
	debugfs_create_file("pinconf-pins", S_IFREG | S_IRUGO,
			    devroot, pctldev, &pinconf_pins_ops);
	debugfs_create_file("pinconf-groups", S_IFREG | S_IRUGO,
			    devroot, pctldev, &pinconf_groups_ops);
	debugfs_create_file("pinconf-config",  (S_IRUGO | S_IWUSR | S_IWGRP),
			    devroot, pctldev, &pinconf_dbg_pinconfig_fops);
}

#endif