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