drivers/pinctrl/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
  11 #define DRV_NAME "sh-pfc"
  12 #define pr_fmt(fmt) KBUILD_MODNAME " pinctrl: " fmt
  13
  14 #include <linux/device.h>
  15 #include <linux/err.h>
  16 #include <linux/init.h>
  17 #include <linux/module.h>
  18 #include <linux/pinctrl/consumer.h>
  19 #include <linux/pinctrl/pinconf.h>
  20 #include <linux/pinctrl/pinconf-generic.h>
  21 #include <linux/pinctrl/pinctrl.h>
  22 #include <linux/pinctrl/pinmux.h>
  23 #include <linux/slab.h>
  24 #include <linux/spinlock.h>
  25
  26 #include "core.h"
  27
  28 struct sh_pfc_pinctrl {
  29         struct pinctrl_dev *pctl;
  30         struct pinctrl_desc pctl_desc;
  31         struct pinctrl_gpio_range range;
  32
  33         struct sh_pfc *pfc;
  34
  35         struct pinmux_gpio **functions;
  36         unsigned int nr_functions;
  37
  38         struct pinctrl_pin_desc *pads;
  39         unsigned int nr_pads;
  40 };
  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 const 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 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->info->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->info->gpios[offset].flags &= ~PINMUX_FLAG_TYPE;
 176         pfc->info->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->info->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->info->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 const 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->info->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 const 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 void sh_pfc_map_one_gpio(struct sh_pfc *pfc, struct sh_pfc_pinctrl *pmx,
 319                                 struct pinmux_gpio *gpio, unsigned offset)
 320 {
 321         struct pinmux_data_reg *dummy;
 322         int bit;
 323
 324         gpio->flags &= ~PINMUX_FLAG_TYPE;
 325
 326         if (sh_pfc_get_data_reg(pfc, offset, &dummy, &bit) == 0)
 327                 gpio->flags |= PINMUX_TYPE_GPIO;
 328         else {
 329                 gpio->flags |= PINMUX_TYPE_FUNCTION;
 330                 pmx->nr_functions++;
 331         }
 332 }
 333
 334 /* pinmux ranges -> pinctrl pin descs */
 335 static int sh_pfc_map_gpios(struct sh_pfc *pfc, struct sh_pfc_pinctrl *pmx)
 336 {
 337         unsigned long flags;
 338         int i;
 339
 340         pmx->nr_pads = pfc->info->last_gpio - pfc->info->first_gpio + 1;
 341
 342         pmx->pads = devm_kzalloc(pfc->dev, sizeof(*pmx->pads) * pmx->nr_pads,
 343                                  GFP_KERNEL);
 344         if (unlikely(!pmx->pads)) {
 345                 pmx->nr_pads = 0;
 346                 return -ENOMEM;
 347         }
 348
 349         spin_lock_irqsave(&pfc->lock, flags);
 350
 351         /*
 352          * We don't necessarily have a 1:1 mapping between pin and linux
 353          * GPIO number, as the latter maps to the associated enum_id.
 354          * Care needs to be taken to translate back to pin space when
 355          * dealing with any pin configurations.
 356          */
 357         for (i = 0; i < pmx->nr_pads; i++) {
 358                 struct pinctrl_pin_desc *pin = pmx->pads + i;
 359                 struct pinmux_gpio *gpio = pfc->info->gpios + i;
 360
 361                 pin->number = pfc->info->first_gpio + i;
 362                 pin->name = gpio->name;
 363
 364                 /* XXX */
 365                 if (unlikely(!gpio->enum_id))
 366                         continue;
 367
 368                 sh_pfc_map_one_gpio(pfc, pmx, gpio, i);
 369         }
 370
 371         spin_unlock_irqrestore(&pfc->lock, flags);
 372
 373         return 0;
 374 }
 375
 376 static int sh_pfc_map_functions(struct sh_pfc *pfc, struct sh_pfc_pinctrl *pmx)
 377 {
 378         int i, fn;
 379
 380         pmx->functions = devm_kzalloc(pfc->dev, pmx->nr_functions *
 381                                       sizeof(*pmx->functions), GFP_KERNEL);
 382         if (unlikely(!pmx->functions))
 383                 return -ENOMEM;
 384
 385         for (i = fn = 0; i < pmx->nr_pads; i++) {
 386                 struct pinmux_gpio *gpio = pfc->info->gpios + i;
 387
 388                 if ((gpio->flags & PINMUX_FLAG_TYPE) == PINMUX_TYPE_FUNCTION)
 389                         pmx->functions[fn++] = gpio;
 390         }
 391
 392         return 0;
 393 }
 394
 395 int sh_pfc_register_pinctrl(struct sh_pfc *pfc)
 396 {
 397         struct sh_pfc_pinctrl *pmx;
 398         int ret;
 399
 400         pmx = devm_kzalloc(pfc->dev, sizeof(*pmx), GFP_KERNEL);
 401         if (unlikely(!pmx))
 402                 return -ENOMEM;
 403
 404         pmx->pfc = pfc;
 405         pfc->pinctrl = pmx;
 406
 407         ret = sh_pfc_map_gpios(pfc, pmx);
 408         if (unlikely(ret != 0))
 409                 return ret;
 410
 411         ret = sh_pfc_map_functions(pfc, pmx);
 412         if (unlikely(ret != 0))
 413                 return ret;
 414
 415         pmx->pctl_desc.name = DRV_NAME;
 416         pmx->pctl_desc.owner = THIS_MODULE;
 417         pmx->pctl_desc.pctlops = &sh_pfc_pinctrl_ops;
 418         pmx->pctl_desc.pmxops = &sh_pfc_pinmux_ops;
 419         pmx->pctl_desc.confops = &sh_pfc_pinconf_ops;
 420         pmx->pctl_desc.pins = pmx->pads;
 421         pmx->pctl_desc.npins = pmx->nr_pads;
 422
 423         pmx->pctl = pinctrl_register(&pmx->pctl_desc, pfc->dev, pmx);
 424         if (IS_ERR(pmx->pctl))
 425                 return PTR_ERR(pmx->pctl);
 426
 427         pmx->range.name = DRV_NAME,
 428         pmx->range.id = 0;
 429         pmx->range.npins = pfc->info->last_gpio - pfc->info->first_gpio + 1;
 430         pmx->range.base = pfc->info->first_gpio;
 431         pmx->range.pin_base = pfc->info->first_gpio;
 432
 433         pinctrl_add_gpio_range(pmx->pctl, &pmx->range);
 434
 435         return 0;
 436 }
 437
 438 int sh_pfc_unregister_pinctrl(struct sh_pfc *pfc)
 439 {
 440         struct sh_pfc_pinctrl *pmx = pfc->pinctrl;
 441
 442         pinctrl_unregister(pmx->pctl);
 443
 444         pfc->pinctrl = NULL;
 445         return 0;
 446 }