drivers/pinctrl/pinconf.c

   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