drivers/pinctrl/zte/pinctrl-zx.c

   1 /*
   2  * Copyright (C) 2017 Sanechips Technology Co., Ltd.
   3  * Copyright 2017 Linaro Ltd.
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License version 2 as
   7  * published by the Free Software Foundation.
   8  */
   9
  10 #include <linux/io.h>
  11 #include <linux/of.h>
  12 #include <linux/of_address.h>
  13 #include <linux/of_device.h>
  14 #include <linux/pinctrl/pinctrl.h>
  15 #include <linux/pinctrl/pinconf-generic.h>
  16 #include <linux/pinctrl/pinmux.h>
  17 #include <linux/platform_device.h>
  18 #include <linux/slab.h>
  19
  20 #include "../core.h"
  21 #include "../pinctrl-utils.h"
  22 #include "../pinmux.h"
  23 #include "pinctrl-zx.h"
  24
  25 #define ZX_PULL_DOWN            BIT(0)
  26 #define ZX_PULL_UP              BIT(1)
  27 #define ZX_INPUT_ENABLE         BIT(3)
  28 #define ZX_DS_SHIFT             4
  29 #define ZX_DS_MASK              (0x7 << ZX_DS_SHIFT)
  30 #define ZX_DS_VALUE(x)          (((x) << ZX_DS_SHIFT) & ZX_DS_MASK)
  31 #define ZX_SLEW                 BIT(8)
  32
  33 struct zx_pinctrl {
  34         struct pinctrl_dev *pctldev;
  35         struct device *dev;
  36         void __iomem *base;
  37         void __iomem *aux_base;
  38         spinlock_t lock;
  39         struct zx_pinctrl_soc_info *info;
  40 };
  41
  42 static int zx_dt_node_to_map(struct pinctrl_dev *pctldev,
  43                              struct device_node *np_config,
  44                              struct pinctrl_map **map, u32 *num_maps)
  45 {
  46         return pinconf_generic_dt_node_to_map(pctldev, np_config, map,
  47                                               num_maps, PIN_MAP_TYPE_INVALID);
  48 }
  49
  50 static const struct pinctrl_ops zx_pinctrl_ops = {
  51         .dt_node_to_map = zx_dt_node_to_map,
  52         .dt_free_map = pinctrl_utils_free_map,
  53         .get_groups_count = pinctrl_generic_get_group_count,
  54         .get_group_name = pinctrl_generic_get_group_name,
  55         .get_group_pins = pinctrl_generic_get_group_pins,
  56 };
  57
  58 #define NONAON_MVAL 2
  59
  60 static int zx_set_mux(struct pinctrl_dev *pctldev, unsigned int func_selector,
  61                       unsigned int group_selector)
  62 {
  63         struct zx_pinctrl *zpctl = pinctrl_dev_get_drvdata(pctldev);
  64         struct zx_pinctrl_soc_info *info = zpctl->info;
  65         const struct pinctrl_pin_desc *pindesc = info->pins + group_selector;
  66         struct zx_pin_data *data = pindesc->drv_data;
  67         struct zx_mux_desc *mux;
  68         u32 mask, offset, bitpos;
  69         struct function_desc *func;
  70         unsigned long flags;
  71         u32 val, mval;
  72
  73         /* Skip reserved pin */
  74         if (!data)
  75                 return -EINVAL;
  76
  77         mux = data->muxes;
  78         mask = (1 << data->width) - 1;
  79         offset = data->offset;
  80         bitpos = data->bitpos;
  81
  82         func = pinmux_generic_get_function(pctldev, func_selector);
  83         if (!func)
  84                 return -EINVAL;
  85
  86         while (mux->name) {
  87                 if (strcmp(mux->name, func->name) == 0)
  88                         break;
  89                 mux++;
  90         }
  91
  92         /* Found mux value to be written */
  93         mval = mux->muxval;
  94
  95         spin_lock_irqsave(&zpctl->lock, flags);
  96
  97         if (data->aon_pin) {
  98                 /*
  99                  * It's an AON pin, whose mux register offset and bit position
 100                  * can be caluculated from pin number.  Each register covers 16
 101                  * pins, and each pin occupies 2 bits.
 102                  */
 103                 u16 aoffset = pindesc->number / 16 * 4;
 104                 u16 abitpos = (pindesc->number % 16) * 2;
 105
 106                 if (mval & AON_MUX_FLAG) {
 107                         /*
 108                          * This is a mux value that needs to be written into
 109                          * AON pinmux register.  Write it and then we're done.
 110                          */
 111                         val = readl(zpctl->aux_base + aoffset);
 112                         val &= ~(0x3 << abitpos);
 113                         val |= (mval & 0x3) << abitpos;
 114                         writel(val, zpctl->aux_base + aoffset);
 115                 } else {
 116                         /*
 117                          * It's a mux value that needs to be written into TOP
 118                          * pinmux register.
 119                          */
 120                         val = readl(zpctl->base + offset);
 121                         val &= ~(mask << bitpos);
 122                         val |= (mval & mask) << bitpos;
 123                         writel(val, zpctl->base + offset);
 124
 125                         /*
 126                          * In this case, the AON pinmux register needs to be
 127                          * set up to select non-AON function.
 128                          */
 129                         val = readl(zpctl->aux_base + aoffset);
 130                         val &= ~(0x3 << abitpos);
 131                         val |= NONAON_MVAL << abitpos;
 132                         writel(val, zpctl->aux_base + aoffset);
 133                 }
 134
 135         } else {
 136                 /*
 137                  * This is a TOP pin, and we only need to set up TOP pinmux
 138                  * register and then we're done with it.
 139                  */
 140                 val = readl(zpctl->base + offset);
 141                 val &= ~(mask << bitpos);
 142                 val |= (mval & mask) << bitpos;
 143                 writel(val, zpctl->base + offset);
 144         }
 145
 146         spin_unlock_irqrestore(&zpctl->lock, flags);
 147
 148         return 0;
 149 }
 150
 151 static const struct pinmux_ops zx_pinmux_ops = {
 152         .get_functions_count = pinmux_generic_get_function_count,
 153         .get_function_name = pinmux_generic_get_function_name,
 154         .get_function_groups = pinmux_generic_get_function_groups,
 155         .set_mux = zx_set_mux,
 156 };
 157
 158 static int zx_pin_config_get(struct pinctrl_dev *pctldev, unsigned int pin,
 159                              unsigned long *config)
 160 {
 161         struct zx_pinctrl *zpctl = pinctrl_dev_get_drvdata(pctldev);
 162         struct zx_pinctrl_soc_info *info = zpctl->info;
 163         const struct pinctrl_pin_desc *pindesc = info->pins + pin;
 164         struct zx_pin_data *data = pindesc->drv_data;
 165         enum pin_config_param param = pinconf_to_config_param(*config);
 166         u32 val;
 167
 168         /* Skip reserved pin */
 169         if (!data)
 170                 return -EINVAL;
 171
 172         val = readl(zpctl->aux_base + data->coffset);
 173         val = val >> data->cbitpos;
 174
 175         switch (param) {
 176         case PIN_CONFIG_BIAS_PULL_DOWN:
 177                 val &= ZX_PULL_DOWN;
 178                 val = !!val;
 179                 if (val == 0)
 180                         return -EINVAL;
 181                 break;
 182         case PIN_CONFIG_BIAS_PULL_UP:
 183                 val &= ZX_PULL_UP;
 184                 val = !!val;
 185                 if (val == 0)
 186                         return -EINVAL;
 187                 break;
 188         case PIN_CONFIG_INPUT_ENABLE:
 189                 val &= ZX_INPUT_ENABLE;
 190                 val = !!val;
 191                 if (val == 0)
 192                         return -EINVAL;
 193                 break;
 194         case PIN_CONFIG_DRIVE_STRENGTH:
 195                 val &= ZX_DS_MASK;
 196                 val = val >> ZX_DS_SHIFT;
 197                 break;
 198         case PIN_CONFIG_SLEW_RATE:
 199                 val &= ZX_SLEW;
 200                 val = !!val;
 201                 break;
 202         default:
 203                 return -ENOTSUPP;
 204         }
 205
 206         *config = pinconf_to_config_packed(param, val);
 207
 208         return 0;
 209 }
 210
 211 static int zx_pin_config_set(struct pinctrl_dev *pctldev, unsigned int pin,
 212                              unsigned long *configs, unsigned int num_configs)
 213 {
 214         struct zx_pinctrl *zpctl = pinctrl_dev_get_drvdata(pctldev);
 215         struct zx_pinctrl_soc_info *info = zpctl->info;
 216         const struct pinctrl_pin_desc *pindesc = info->pins + pin;
 217         struct zx_pin_data *data = pindesc->drv_data;
 218         enum pin_config_param param;
 219         u32 val, arg;
 220         int i;
 221
 222         /* Skip reserved pin */
 223         if (!data)
 224                 return -EINVAL;
 225
 226         val = readl(zpctl->aux_base + data->coffset);
 227
 228         for (i = 0; i < num_configs; i++) {
 229                 param = pinconf_to_config_param(configs[i]);
 230                 arg = pinconf_to_config_argument(configs[i]);
 231
 232                 switch (param) {
 233                 case PIN_CONFIG_BIAS_PULL_DOWN:
 234                         val |= ZX_PULL_DOWN << data->cbitpos;
 235                         break;
 236                 case PIN_CONFIG_BIAS_PULL_UP:
 237                         val |= ZX_PULL_UP << data->cbitpos;
 238                         break;
 239                 case PIN_CONFIG_INPUT_ENABLE:
 240                         val |= ZX_INPUT_ENABLE << data->cbitpos;
 241                         break;
 242                 case PIN_CONFIG_DRIVE_STRENGTH:
 243                         val &= ~(ZX_DS_MASK << data->cbitpos);
 244                         val |= ZX_DS_VALUE(arg) << data->cbitpos;
 245                         break;
 246                 case PIN_CONFIG_SLEW_RATE:
 247                         if (arg)
 248                                 val |= ZX_SLEW << data->cbitpos;
 249                         else
 250                                 val &= ~ZX_SLEW << data->cbitpos;
 251                         break;
 252                 default:
 253                         return -ENOTSUPP;
 254                 }
 255         }
 256
 257         writel(val, zpctl->aux_base + data->coffset);
 258         return 0;
 259 }
 260
 261 static const struct pinconf_ops zx_pinconf_ops = {
 262         .pin_config_set = zx_pin_config_set,
 263         .pin_config_get = zx_pin_config_get,
 264         .is_generic = true,
 265 };
 266
 267 static int zx_pinctrl_build_state(struct platform_device *pdev)
 268 {
 269         struct zx_pinctrl *zpctl = platform_get_drvdata(pdev);
 270         struct zx_pinctrl_soc_info *info = zpctl->info;
 271         struct pinctrl_dev *pctldev = zpctl->pctldev;
 272         struct function_desc *functions;
 273         int nfunctions;
 274         struct group_desc *groups;
 275         int ngroups;
 276         int i;
 277
 278         /* Every single pin composes a group */
 279         ngroups = info->npins;
 280         groups = devm_kzalloc(&pdev->dev, ngroups * sizeof(*groups),
 281                               GFP_KERNEL);
 282         if (!groups)
 283                 return -ENOMEM;
 284
 285         for (i = 0; i < ngroups; i++) {
 286                 const struct pinctrl_pin_desc *pindesc = info->pins + i;
 287                 struct group_desc *group = groups + i;
 288
 289                 group->name = pindesc->name;
 290                 group->pins = (int *) &pindesc->number;
 291                 group->num_pins = 1;
 292                 radix_tree_insert(&pctldev->pin_group_tree, i, group);
 293         }
 294
 295         pctldev->num_groups = ngroups;
 296
 297         /* Build function list from pin mux functions */
 298         functions = kcalloc(info->npins, sizeof(*functions), GFP_KERNEL);
 299         if (!functions)
 300                 return -ENOMEM;
 301
 302         nfunctions = 0;
 303         for (i = 0; i < info->npins; i++) {
 304                 const struct pinctrl_pin_desc *pindesc = info->pins + i;
 305                 struct zx_pin_data *data = pindesc->drv_data;
 306                 struct zx_mux_desc *mux;
 307
 308                 /* Reserved pins do not have a drv_data at all */
 309                 if (!data)
 310                         continue;
 311
 312                 /* Loop over all muxes for the pin */
 313                 mux = data->muxes;
 314                 while (mux->name) {
 315                         struct function_desc *func = functions;
 316
 317                         /* Search function list for given mux */
 318                         while (func->name) {
 319                                 if (strcmp(mux->name, func->name) == 0) {
 320                                         /* Function exists */
 321                                         func->num_group_names++;
 322                                         break;
 323                                 }
 324                                 func++;
 325                         }
 326
 327                         if (!func->name) {
 328                                 /* New function */
 329                                 func->name = mux->name;
 330                                 func->num_group_names = 1;
 331                                 radix_tree_insert(&pctldev->pin_function_tree,
 332                                                   nfunctions++, func);
 333                         }
 334
 335                         mux++;
 336                 }
 337         }
 338
 339         pctldev->num_functions = nfunctions;
 340         functions = krealloc(functions, nfunctions * sizeof(*functions),
 341                              GFP_KERNEL);
 342
 343         /* Find pin groups for every single function */
 344         for (i = 0; i < info->npins; i++) {
 345                 const struct pinctrl_pin_desc *pindesc = info->pins + i;
 346                 struct zx_pin_data *data = pindesc->drv_data;
 347                 struct zx_mux_desc *mux;
 348
 349                 if (!data)
 350                         continue;
 351
 352                 mux = data->muxes;
 353                 while (mux->name) {
 354                         struct function_desc *func;
 355                         const char **group;
 356                         int j;
 357
 358                         /* Find function for given mux */
 359                         for (j = 0; j < nfunctions; j++)
 360                                 if (strcmp(functions[j].name, mux->name) == 0)
 361                                         break;
 362
 363                         func = functions + j;
 364                         if (!func->group_names) {
 365                                 func->group_names = devm_kzalloc(&pdev->dev,
 366                                                 func->num_group_names *
 367                                                 sizeof(*func->group_names),
 368                                                 GFP_KERNEL);
 369                                 if (!func->group_names) {
 370                                         kfree(functions);
 371                                         return -ENOMEM;
 372                                 }
 373                         }
 374
 375                         group = func->group_names;
 376                         while (*group)
 377                                 group++;
 378                         *group = pindesc->name;
 379
 380                         mux++;
 381                 }
 382         }
 383
 384         return 0;
 385 }
 386
 387 int zx_pinctrl_init(struct platform_device *pdev,
 388                     struct zx_pinctrl_soc_info *info)
 389 {
 390         struct pinctrl_desc *pctldesc;
 391         struct zx_pinctrl *zpctl;
 392         struct device_node *np;
 393         struct resource *res;
 394         int ret;
 395
 396         zpctl = devm_kzalloc(&pdev->dev, sizeof(*zpctl), GFP_KERNEL);
 397         if (!zpctl)
 398                 return -ENOMEM;
 399
 400         spin_lock_init(&zpctl->lock);
 401
 402         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 403         zpctl->base = devm_ioremap_resource(&pdev->dev, res);
 404         if (IS_ERR(zpctl->base))
 405                 return PTR_ERR(zpctl->base);
 406
 407         np = of_parse_phandle(pdev->dev.of_node, "zte,auxiliary-controller", 0);
 408         if (!np) {
 409                 dev_err(&pdev->dev, "failed to find auxiliary controller\n");
 410                 return -ENODEV;
 411         }
 412
 413         zpctl->aux_base = of_iomap(np, 0);
 414         of_node_put(np);
 415         if (!zpctl->aux_base)
 416                 return -ENOMEM;
 417
 418         zpctl->dev = &pdev->dev;
 419         zpctl->info = info;
 420
 421         pctldesc = devm_kzalloc(&pdev->dev, sizeof(*pctldesc), GFP_KERNEL);
 422         if (!pctldesc)
 423                 return -ENOMEM;
 424
 425         pctldesc->name = dev_name(&pdev->dev);
 426         pctldesc->owner = THIS_MODULE;
 427         pctldesc->pins = info->pins;
 428         pctldesc->npins = info->npins;
 429         pctldesc->pctlops = &zx_pinctrl_ops;
 430         pctldesc->pmxops = &zx_pinmux_ops;
 431         pctldesc->confops = &zx_pinconf_ops;
 432
 433         zpctl->pctldev = devm_pinctrl_register(&pdev->dev, pctldesc, zpctl);
 434         if (IS_ERR(zpctl->pctldev)) {
 435                 ret = PTR_ERR(zpctl->pctldev);
 436                 dev_err(&pdev->dev, "failed to register pinctrl: %d\n", ret);
 437                 return ret;
 438         }
 439
 440         platform_set_drvdata(pdev, zpctl);
 441
 442         ret = zx_pinctrl_build_state(pdev);
 443         if (ret) {
 444                 dev_err(&pdev->dev, "failed to build state: %d\n", ret);
 445                 return ret;
 446         }
 447
 448         dev_info(&pdev->dev, "initialized pinctrl driver\n");
 449         return 0;
 450 }