drivers/sh/pfc/pinctrl.c

   1 /*
   2  * SuperH Pin Function Controller pinmux support.
   3  *
   4  * Copyright (C) 2012  Paul Mundt
   5  *
   6  * This file is subject to the terms and conditions of the GNU General Public
   7  * License.  See the file "COPYING" in the main directory of this archive
   8  * for more details.
   9  */
  10 #define DRV_NAME "pinctrl-sh_pfc"
  11
  12 #define pr_fmt(fmt) DRV_NAME " " KBUILD_MODNAME ": " fmt
  13
  14 #include <linux/init.h>
  15 #include <linux/module.h>
  16 #include <linux/sh_pfc.h>
  17 #include <linux/err.h>
  18 #include <linux/slab.h>
  19 #include <linux/spinlock.h>
  20 #include <linux/platform_device.h>
  21 #include <linux/pinctrl/consumer.h>
  22 #include <linux/pinctrl/pinctrl.h>
  23 #include <linux/pinctrl/pinconf.h>
  24 #include <linux/pinctrl/pinmux.h>
  25 #include <linux/pinctrl/pinconf-generic.h>
  26
  27 struct sh_pfc_pinctrl {
  28         struct pinctrl_dev *pctl;
  29         struct sh_pfc *pfc;
  30
  31         struct pinmux_gpio **functions;
  32         unsigned int nr_functions;
  33
  34         struct pinctrl_pin_desc *pads;
  35         unsigned int nr_pads;
  36
  37         spinlock_t lock;
  38 };
  39
  40 static struct sh_pfc_pinctrl *sh_pfc_pmx;
  41
  42 static int sh_pfc_get_groups_count(struct pinctrl_dev *pctldev)
  43 {
  44         struct sh_pfc_pinctrl *pmx = pinctrl_dev_get_drvdata(pctldev);
  45
  46         return pmx->nr_pads;
  47 }
  48
  49 static const char *sh_pfc_get_group_name(struct pinctrl_dev *pctldev,
  50                                          unsigned selector)
  51 {
  52         struct sh_pfc_pinctrl *pmx = pinctrl_dev_get_drvdata(pctldev);
  53
  54         return pmx->pads[selector].name;
  55 }
  56
  57 static int sh_pfc_get_group_pins(struct pinctrl_dev *pctldev, unsigned group,
  58                                  const unsigned **pins, unsigned *num_pins)
  59 {
  60         struct sh_pfc_pinctrl *pmx = pinctrl_dev_get_drvdata(pctldev);
  61
  62         *pins = &pmx->pads[group].number;
  63         *num_pins = 1;
  64
  65         return 0;
  66 }
  67
  68 static void sh_pfc_pin_dbg_show(struct pinctrl_dev *pctldev, struct seq_file *s,
  69                                 unsigned offset)
  70 {
  71         seq_printf(s, "%s", DRV_NAME);
  72 }
  73
  74 static struct pinctrl_ops sh_pfc_pinctrl_ops = {
  75         .get_groups_count       = sh_pfc_get_groups_count,
  76         .get_group_name         = sh_pfc_get_group_name,
  77         .get_group_pins         = sh_pfc_get_group_pins,
  78         .pin_dbg_show           = sh_pfc_pin_dbg_show,
  79 };
  80
  81 static int sh_pfc_get_functions_count(struct pinctrl_dev *pctldev)
  82 {
  83         struct sh_pfc_pinctrl *pmx = pinctrl_dev_get_drvdata(pctldev);
  84
  85         return pmx->nr_functions;
  86 }
  87
  88 static const char *sh_pfc_get_function_name(struct pinctrl_dev *pctldev,
  89                                             unsigned selector)
  90 {
  91         struct sh_pfc_pinctrl *pmx = pinctrl_dev_get_drvdata(pctldev);
  92
  93         return pmx->functions[selector]->name;
  94 }
  95
  96 static int sh_pfc_get_function_groups(struct pinctrl_dev *pctldev, unsigned func,
  97                                       const char * const **groups,
  98                                       unsigned * const num_groups)
  99 {
 100         struct sh_pfc_pinctrl *pmx = pinctrl_dev_get_drvdata(pctldev);
 101
 102         *groups = &pmx->functions[func]->name;
 103         *num_groups = 1;
 104
 105         return 0;
 106 }
 107
 108 static int sh_pfc_noop_enable(struct pinctrl_dev *pctldev, unsigned func,
 109                               unsigned group)
 110 {
 111         return 0;
 112 }
 113
 114 static void sh_pfc_noop_disable(struct pinctrl_dev *pctldev, unsigned func,
 115                                 unsigned group)
 116 {
 117 }
 118
 119 static inline int sh_pfc_config_function(struct sh_pfc *pfc, unsigned offset)
 120 {
 121         if (sh_pfc_config_gpio(pfc, offset,
 122                                PINMUX_TYPE_FUNCTION,
 123                                GPIO_CFG_DRYRUN) != 0)
 124                 return -EINVAL;
 125
 126         if (sh_pfc_config_gpio(pfc, offset,
 127                                PINMUX_TYPE_FUNCTION,
 128                                GPIO_CFG_REQ) != 0)
 129                 return -EINVAL;
 130
 131         return 0;
 132 }
 133
 134 static int sh_pfc_reconfig_pin(struct sh_pfc *pfc, unsigned offset,
 135                                int new_type)
 136 {
 137         unsigned long flags;
 138         int pinmux_type;
 139         int ret = -EINVAL;
 140
 141         spin_lock_irqsave(&pfc->lock, flags);
 142
 143         pinmux_type = pfc->gpios[offset].flags & PINMUX_FLAG_TYPE;
 144
 145         /*
 146          * See if the present config needs to first be de-configured.
 147          */
 148         switch (pinmux_type) {
 149         case PINMUX_TYPE_GPIO:
 150                 break;
 151         case PINMUX_TYPE_OUTPUT:
 152         case PINMUX_TYPE_INPUT:
 153         case PINMUX_TYPE_INPUT_PULLUP:
 154         case PINMUX_TYPE_INPUT_PULLDOWN:
 155                 sh_pfc_config_gpio(pfc, offset, pinmux_type, GPIO_CFG_FREE);
 156                 break;
 157         default:
 158                 goto err;
 159         }
 160
 161         /*
 162          * Dry run
 163          */
 164         if (sh_pfc_config_gpio(pfc, offset, new_type,
 165                                GPIO_CFG_DRYRUN) != 0)
 166                 goto err;
 167
 168         /*
 169          * Request
 170          */
 171         if (sh_pfc_config_gpio(pfc, offset, new_type,
 172                                GPIO_CFG_REQ) != 0)
 173                 goto err;
 174
 175         pfc->gpios[offset].flags &= ~PINMUX_FLAG_TYPE;
 176         pfc->gpios[offset].flags |= new_type;
 177
 178         ret = 0;
 179
 180 err:
 181         spin_unlock_irqrestore(&pfc->lock, flags);
 182
 183         return ret;
 184 }
 185
 186
 187 static int sh_pfc_gpio_request_enable(struct pinctrl_dev *pctldev,
 188                                       struct pinctrl_gpio_range *range,
 189                                       unsigned offset)
 190 {
 191         struct sh_pfc_pinctrl *pmx = pinctrl_dev_get_drvdata(pctldev);
 192         struct sh_pfc *pfc = pmx->pfc;
 193         unsigned long flags;
 194         int ret, pinmux_type;
 195
 196         spin_lock_irqsave(&pfc->lock, flags);
 197
 198         pinmux_type = pfc->gpios[offset].flags & PINMUX_FLAG_TYPE;
 199
 200         switch (pinmux_type) {
 201         case PINMUX_TYPE_FUNCTION:
 202                 pr_notice_once("Use of GPIO API for function requests is "
 203                                "deprecated, convert to pinctrl\n");
 204                 /* handle for now */
 205                 ret = sh_pfc_config_function(pfc, offset);
 206                 if (unlikely(ret < 0))
 207                         goto err;
 208
 209                 break;
 210         case PINMUX_TYPE_GPIO:
 211         case PINMUX_TYPE_INPUT:
 212         case PINMUX_TYPE_OUTPUT:
 213                 break;
 214         default:
 215                 pr_err("Unsupported mux type (%d), bailing...\n", pinmux_type);
 216                 ret = -ENOTSUPP;
 217                 goto err;
 218         }
 219
 220         ret = 0;
 221
 222 err:
 223         spin_unlock_irqrestore(&pfc->lock, flags);
 224
 225         return ret;
 226 }
 227
 228 static void sh_pfc_gpio_disable_free(struct pinctrl_dev *pctldev,
 229                                      struct pinctrl_gpio_range *range,
 230                                      unsigned offset)
 231 {
 232         struct sh_pfc_pinctrl *pmx = pinctrl_dev_get_drvdata(pctldev);
 233         struct sh_pfc *pfc = pmx->pfc;
 234         unsigned long flags;
 235         int pinmux_type;
 236
 237         spin_lock_irqsave(&pfc->lock, flags);
 238
 239         pinmux_type = pfc->gpios[offset].flags & PINMUX_FLAG_TYPE;
 240
 241         sh_pfc_config_gpio(pfc, offset, pinmux_type, GPIO_CFG_FREE);
 242
 243         spin_unlock_irqrestore(&pfc->lock, flags);
 244 }
 245
 246 static int sh_pfc_gpio_set_direction(struct pinctrl_dev *pctldev,
 247                                      struct pinctrl_gpio_range *range,
 248                                      unsigned offset, bool input)
 249 {
 250         struct sh_pfc_pinctrl *pmx = pinctrl_dev_get_drvdata(pctldev);
 251         int type = input ? PINMUX_TYPE_INPUT : PINMUX_TYPE_OUTPUT;
 252
 253         return sh_pfc_reconfig_pin(pmx->pfc, offset, type);
 254 }
 255
 256 static struct pinmux_ops sh_pfc_pinmux_ops = {
 257         .get_functions_count    = sh_pfc_get_functions_count,
 258         .get_function_name      = sh_pfc_get_function_name,
 259         .get_function_groups    = sh_pfc_get_function_groups,
 260         .enable                 = sh_pfc_noop_enable,
 261         .disable                = sh_pfc_noop_disable,
 262         .gpio_request_enable    = sh_pfc_gpio_request_enable,
 263         .gpio_disable_free      = sh_pfc_gpio_disable_free,
 264         .gpio_set_direction     = sh_pfc_gpio_set_direction,
 265 };
 266
 267 static int sh_pfc_pinconf_get(struct pinctrl_dev *pctldev, unsigned pin,
 268                               unsigned long *config)
 269 {
 270         struct sh_pfc_pinctrl *pmx = pinctrl_dev_get_drvdata(pctldev);
 271         struct sh_pfc *pfc = pmx->pfc;
 272
 273         *config = pfc->gpios[pin].flags & PINMUX_FLAG_TYPE;
 274
 275         return 0;
 276 }
 277
 278 static int sh_pfc_pinconf_set(struct pinctrl_dev *pctldev, unsigned pin,
 279                               unsigned long config)
 280 {
 281         struct sh_pfc_pinctrl *pmx = pinctrl_dev_get_drvdata(pctldev);
 282
 283         /* Validate the new type */
 284         if (config >= PINMUX_FLAG_TYPE)
 285                 return -EINVAL;
 286
 287         return sh_pfc_reconfig_pin(pmx->pfc, pin, config);
 288 }
 289
 290 static void sh_pfc_pinconf_dbg_show(struct pinctrl_dev *pctldev,
 291                                     struct seq_file *s, unsigned pin)
 292 {
 293         const char *pinmux_type_str[] = {
 294                 [PINMUX_TYPE_NONE]              = "none",
 295                 [PINMUX_TYPE_FUNCTION]          = "function",
 296                 [PINMUX_TYPE_GPIO]              = "gpio",
 297                 [PINMUX_TYPE_OUTPUT]            = "output",
 298                 [PINMUX_TYPE_INPUT]             = "input",
 299                 [PINMUX_TYPE_INPUT_PULLUP]      = "input bias pull up",
 300                 [PINMUX_TYPE_INPUT_PULLDOWN]    = "input bias pull down",
 301         };
 302         unsigned long config;
 303         int rc;
 304
 305         rc = sh_pfc_pinconf_get(pctldev, pin, &config);
 306         if (unlikely(rc != 0))
 307                 return;
 308
 309         seq_printf(s, " %s", pinmux_type_str[config]);
 310 }
 311
 312 static struct pinconf_ops sh_pfc_pinconf_ops = {
 313         .pin_config_get         = sh_pfc_pinconf_get,
 314         .pin_config_set         = sh_pfc_pinconf_set,
 315         .pin_config_dbg_show    = sh_pfc_pinconf_dbg_show,
 316 };
 317
 318 static struct pinctrl_gpio_range sh_pfc_gpio_range = {
 319         .name           = DRV_NAME,
 320         .id             = 0,
 321 };
 322
 323 static struct pinctrl_desc sh_pfc_pinctrl_desc = {
 324         .name           = DRV_NAME,
 325         .owner          = THIS_MODULE,
 326         .pctlops        = &sh_pfc_pinctrl_ops,
 327         .pmxops         = &sh_pfc_pinmux_ops,
 328         .confops        = &sh_pfc_pinconf_ops,
 329 };
 330
 331 static inline void sh_pfc_map_one_gpio(struct sh_pfc *pfc,
 332                                        struct sh_pfc_pinctrl *pmx,
 333                                        struct pinmux_gpio *gpio,
 334                                        unsigned offset)
 335 {
 336         struct pinmux_data_reg *dummy;
 337         unsigned long flags;
 338         int bit;
 339
 340         gpio->flags &= ~PINMUX_FLAG_TYPE;
 341
 342         if (sh_pfc_get_data_reg(pfc, offset, &dummy, &bit) == 0)
 343                 gpio->flags |= PINMUX_TYPE_GPIO;
 344         else {
 345                 gpio->flags |= PINMUX_TYPE_FUNCTION;
 346
 347                 spin_lock_irqsave(&pmx->lock, flags);
 348                 pmx->nr_functions++;
 349                 spin_unlock_irqrestore(&pmx->lock, flags);
 350         }
 351 }
 352
 353 /* pinmux ranges -> pinctrl pin descs */
 354 static int sh_pfc_map_gpios(struct sh_pfc *pfc, struct sh_pfc_pinctrl *pmx)
 355 {
 356         unsigned long flags;
 357         int i;
 358
 359         pmx->nr_pads = pfc->last_gpio - pfc->first_gpio + 1;
 360
 361         pmx->pads = kmalloc(sizeof(struct pinctrl_pin_desc) * pmx->nr_pads,
 362                             GFP_KERNEL);
 363         if (unlikely(!pmx->pads)) {
 364                 pmx->nr_pads = 0;
 365                 return -ENOMEM;
 366         }
 367
 368         spin_lock_irqsave(&pfc->lock, flags);
 369
 370         /*
 371          * We don't necessarily have a 1:1 mapping between pin and linux
 372          * GPIO number, as the latter maps to the associated enum_id.
 373          * Care needs to be taken to translate back to pin space when
 374          * dealing with any pin configurations.
 375          */
 376         for (i = 0; i < pmx->nr_pads; i++) {
 377                 struct pinctrl_pin_desc *pin = pmx->pads + i;
 378                 struct pinmux_gpio *gpio = pfc->gpios + i;
 379
 380                 pin->number = pfc->first_gpio + i;
 381                 pin->name = gpio->name;
 382
 383                 /* XXX */
 384                 if (unlikely(!gpio->enum_id))
 385                         continue;
 386
 387                 sh_pfc_map_one_gpio(pfc, pmx, gpio, i);
 388         }
 389
 390         spin_unlock_irqrestore(&pfc->lock, flags);
 391
 392         sh_pfc_pinctrl_desc.pins = pmx->pads;
 393         sh_pfc_pinctrl_desc.npins = pmx->nr_pads;
 394
 395         return 0;
 396 }
 397
 398 static int sh_pfc_map_functions(struct sh_pfc *pfc, struct sh_pfc_pinctrl *pmx)
 399 {
 400         unsigned long flags;
 401         int i, fn;
 402
 403         pmx->functions = kzalloc(pmx->nr_functions * sizeof(void *),
 404                                  GFP_KERNEL);
 405         if (unlikely(!pmx->functions))
 406                 return -ENOMEM;
 407
 408         spin_lock_irqsave(&pmx->lock, flags);
 409
 410         for (i = fn = 0; i < pmx->nr_pads; i++) {
 411                 struct pinmux_gpio *gpio = pfc->gpios + i;
 412
 413                 if ((gpio->flags & PINMUX_FLAG_TYPE) == PINMUX_TYPE_FUNCTION)
 414                         pmx->functions[fn++] = gpio;
 415         }
 416
 417         spin_unlock_irqrestore(&pmx->lock, flags);
 418
 419         return 0;
 420 }
 421
 422 static int sh_pfc_pinctrl_probe(struct platform_device *pdev)
 423 {
 424         struct sh_pfc *pfc;
 425         int ret;
 426
 427         if (unlikely(!sh_pfc_pmx))
 428                 return -ENODEV;
 429
 430         pfc = sh_pfc_pmx->pfc;
 431
 432         ret = sh_pfc_map_gpios(pfc, sh_pfc_pmx);
 433         if (unlikely(ret != 0))
 434                 return ret;
 435
 436         ret = sh_pfc_map_functions(pfc, sh_pfc_pmx);
 437         if (unlikely(ret != 0))
 438                 goto free_pads;
 439
 440         sh_pfc_pmx->pctl = pinctrl_register(&sh_pfc_pinctrl_desc, &pdev->dev,
 441                                             sh_pfc_pmx);
 442         if (IS_ERR(sh_pfc_pmx->pctl)) {
 443                 ret = PTR_ERR(sh_pfc_pmx->pctl);
 444                 goto free_functions;
 445         }
 446
 447         sh_pfc_gpio_range.npins = pfc->last_gpio - pfc->first_gpio + 1;
 448         sh_pfc_gpio_range.base = pfc->first_gpio;
 449         sh_pfc_gpio_range.pin_base = pfc->first_gpio;
 450
 451         pinctrl_add_gpio_range(sh_pfc_pmx->pctl, &sh_pfc_gpio_range);
 452
 453         platform_set_drvdata(pdev, sh_pfc_pmx);
 454
 455         return 0;
 456
 457 free_functions:
 458         kfree(sh_pfc_pmx->functions);
 459 free_pads:
 460         kfree(sh_pfc_pmx->pads);
 461         kfree(sh_pfc_pmx);
 462
 463         return ret;
 464 }
 465
 466 static int sh_pfc_pinctrl_remove(struct platform_device *pdev)
 467 {
 468         struct sh_pfc_pinctrl *pmx = platform_get_drvdata(pdev);
 469
 470         pinctrl_unregister(pmx->pctl);
 471
 472         platform_set_drvdata(pdev, NULL);
 473
 474         kfree(sh_pfc_pmx->functions);
 475         kfree(sh_pfc_pmx->pads);
 476         kfree(sh_pfc_pmx);
 477
 478         return 0;
 479 }
 480
 481 static struct platform_driver sh_pfc_pinctrl_driver = {
 482         .probe          = sh_pfc_pinctrl_probe,
 483         .remove         = sh_pfc_pinctrl_remove,
 484         .driver         = {
 485                 .name   = DRV_NAME,
 486                 .owner  = THIS_MODULE,
 487         },
 488 };
 489
 490 static struct platform_device sh_pfc_pinctrl_device = {
 491         .name           = DRV_NAME,
 492         .id             = -1,
 493 };
 494
 495 static int sh_pfc_pinctrl_init(void)
 496 {
 497         int rc;
 498
 499         rc = platform_driver_register(&sh_pfc_pinctrl_driver);
 500         if (likely(!rc)) {
 501                 rc = platform_device_register(&sh_pfc_pinctrl_device);
 502                 if (unlikely(rc))
 503                         platform_driver_unregister(&sh_pfc_pinctrl_driver);
 504         }
 505
 506         return rc;
 507 }
 508
 509 int sh_pfc_register_pinctrl(struct sh_pfc *pfc)
 510 {
 511         sh_pfc_pmx = kzalloc(sizeof(struct sh_pfc_pinctrl), GFP_KERNEL);
 512         if (unlikely(!sh_pfc_pmx))
 513                 return -ENOMEM;
 514
 515         spin_lock_init(&sh_pfc_pmx->lock);
 516
 517         sh_pfc_pmx->pfc = pfc;
 518
 519         return sh_pfc_pinctrl_init();
 520 }
 521 EXPORT_SYMBOL_GPL(sh_pfc_register_pinctrl);
 522
 523 static void __exit sh_pfc_pinctrl_exit(void)
 524 {
 525         platform_driver_unregister(&sh_pfc_pinctrl_driver);
 526 }
 527 module_exit(sh_pfc_pinctrl_exit);