drivers/pinctrl/berlin/berlin.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Marvell Berlin SoC pinctrl core driver
   4  *
   5  * Copyright (C) 2014 Marvell Technology Group Ltd.
   6  *
   7  * Antoine Ténart <antoine.tenart@free-electrons.com>
   8  */
   9
  10 #include <linux/io.h>
  11 #include <linux/mfd/syscon.h>
  12 #include <linux/module.h>
  13 #include <linux/of.h>
  14 #include <linux/of_address.h>
  15 #include <linux/of_device.h>
  16 #include <linux/pinctrl/pinctrl.h>
  17 #include <linux/pinctrl/pinmux.h>
  18 #include <linux/platform_device.h>
  19 #include <linux/regmap.h>
  20 #include <linux/slab.h>
  21
  22 #include "../core.h"
  23 #include "../pinctrl-utils.h"
  24 #include "berlin.h"
  25
  26 struct berlin_pinctrl {
  27         struct regmap *regmap;
  28         struct device *dev;
  29         const struct berlin_pinctrl_desc *desc;
  30         struct berlin_pinctrl_function *functions;
  31         unsigned nfunctions;
  32         struct pinctrl_dev *pctrl_dev;
  33 };
  34
  35 static int berlin_pinctrl_get_group_count(struct pinctrl_dev *pctrl_dev)
  36 {
  37         struct berlin_pinctrl *pctrl = pinctrl_dev_get_drvdata(pctrl_dev);
  38
  39         return pctrl->desc->ngroups;
  40 }
  41
  42 static const char *berlin_pinctrl_get_group_name(struct pinctrl_dev *pctrl_dev,
  43                                                  unsigned group)
  44 {
  45         struct berlin_pinctrl *pctrl = pinctrl_dev_get_drvdata(pctrl_dev);
  46
  47         return pctrl->desc->groups[group].name;
  48 }
  49
  50 static int berlin_pinctrl_dt_node_to_map(struct pinctrl_dev *pctrl_dev,
  51                                          struct device_node *node,
  52                                          struct pinctrl_map **map,
  53                                          unsigned *num_maps)
  54 {
  55         struct berlin_pinctrl *pctrl = pinctrl_dev_get_drvdata(pctrl_dev);
  56         struct property *prop;
  57         const char *function_name, *group_name;
  58         unsigned reserved_maps = 0;
  59         int ret, ngroups;
  60
  61         *map = NULL;
  62         *num_maps = 0;
  63
  64         ret = of_property_read_string(node, "function", &function_name);
  65         if (ret) {
  66                 dev_err(pctrl->dev,
  67                         "missing function property in node %s\n",
  68                         node->name);
  69                 return -EINVAL;
  70         }
  71
  72         ngroups = of_property_count_strings(node, "groups");
  73         if (ngroups < 0) {
  74                 dev_err(pctrl->dev,
  75                         "missing groups property in node %s\n",
  76                         node->name);
  77                 return -EINVAL;
  78         }
  79
  80         ret = pinctrl_utils_reserve_map(pctrl_dev, map, &reserved_maps,
  81                                         num_maps, ngroups);
  82         if (ret) {
  83                 dev_err(pctrl->dev, "can't reserve map: %d\n", ret);
  84                 return ret;
  85         }
  86
  87         of_property_for_each_string(node, "groups", prop, group_name) {
  88                 ret = pinctrl_utils_add_map_mux(pctrl_dev, map, &reserved_maps,
  89                                                 num_maps, group_name,
  90                                                 function_name);
  91                 if (ret) {
  92                         dev_err(pctrl->dev, "can't add map: %d\n", ret);
  93                         return ret;
  94                 }
  95         }
  96
  97         return 0;
  98 }
  99
 100 static const struct pinctrl_ops berlin_pinctrl_ops = {
 101         .get_groups_count       = &berlin_pinctrl_get_group_count,
 102         .get_group_name         = &berlin_pinctrl_get_group_name,
 103         .dt_node_to_map         = &berlin_pinctrl_dt_node_to_map,
 104         .dt_free_map            = &pinctrl_utils_free_map,
 105 };
 106
 107 static int berlin_pinmux_get_functions_count(struct pinctrl_dev *pctrl_dev)
 108 {
 109         struct berlin_pinctrl *pctrl = pinctrl_dev_get_drvdata(pctrl_dev);
 110
 111         return pctrl->nfunctions;
 112 }
 113
 114 static const char *berlin_pinmux_get_function_name(struct pinctrl_dev *pctrl_dev,
 115                                                    unsigned function)
 116 {
 117         struct berlin_pinctrl *pctrl = pinctrl_dev_get_drvdata(pctrl_dev);
 118
 119         return pctrl->functions[function].name;
 120 }
 121
 122 static int berlin_pinmux_get_function_groups(struct pinctrl_dev *pctrl_dev,
 123                                              unsigned function,
 124                                              const char * const **groups,
 125                                              unsigned * const num_groups)
 126 {
 127         struct berlin_pinctrl *pctrl = pinctrl_dev_get_drvdata(pctrl_dev);
 128
 129         *groups = pctrl->functions[function].groups;
 130         *num_groups = pctrl->functions[function].ngroups;
 131
 132         return 0;
 133 }
 134
 135 static struct berlin_desc_function *
 136 berlin_pinctrl_find_function_by_name(struct berlin_pinctrl *pctrl,
 137                                      const struct berlin_desc_group *group,
 138                                      const char *fname)
 139 {
 140         struct berlin_desc_function *function = group->functions;
 141
 142         while (function->name) {
 143                 if (!strcmp(function->name, fname))
 144                         return function;
 145
 146                 function++;
 147         }
 148
 149         return NULL;
 150 }
 151
 152 static int berlin_pinmux_set(struct pinctrl_dev *pctrl_dev,
 153                              unsigned function,
 154                              unsigned group)
 155 {
 156         struct berlin_pinctrl *pctrl = pinctrl_dev_get_drvdata(pctrl_dev);
 157         const struct berlin_desc_group *group_desc = pctrl->desc->groups + group;
 158         struct berlin_pinctrl_function *func = pctrl->functions + function;
 159         struct berlin_desc_function *function_desc =
 160                 berlin_pinctrl_find_function_by_name(pctrl, group_desc,
 161                                                      func->name);
 162         u32 mask, val;
 163
 164         if (!function_desc)
 165                 return -EINVAL;
 166
 167         mask = GENMASK(group_desc->lsb + group_desc->bit_width - 1,
 168                        group_desc->lsb);
 169         val = function_desc->muxval << group_desc->lsb;
 170         regmap_update_bits(pctrl->regmap, group_desc->offset, mask, val);
 171
 172         return 0;
 173 }
 174
 175 static const struct pinmux_ops berlin_pinmux_ops = {
 176         .get_functions_count    = &berlin_pinmux_get_functions_count,
 177         .get_function_name      = &berlin_pinmux_get_function_name,
 178         .get_function_groups    = &berlin_pinmux_get_function_groups,
 179         .set_mux                = &berlin_pinmux_set,
 180 };
 181
 182 static int berlin_pinctrl_add_function(struct berlin_pinctrl *pctrl,
 183                                        const char *name)
 184 {
 185         struct berlin_pinctrl_function *function = pctrl->functions;
 186
 187         while (function->name) {
 188                 if (!strcmp(function->name, name)) {
 189                         function->ngroups++;
 190                         return -EEXIST;
 191                 }
 192                 function++;
 193         }
 194
 195         function->name = name;
 196         function->ngroups = 1;
 197
 198         pctrl->nfunctions++;
 199
 200         return 0;
 201 }
 202
 203 static int berlin_pinctrl_build_state(struct platform_device *pdev)
 204 {
 205         struct berlin_pinctrl *pctrl = platform_get_drvdata(pdev);
 206         const struct berlin_desc_group *desc_group;
 207         const struct berlin_desc_function *desc_function;
 208         int i, max_functions = 0;
 209
 210         pctrl->nfunctions = 0;
 211
 212         for (i = 0; i < pctrl->desc->ngroups; i++) {
 213                 desc_group = pctrl->desc->groups + i;
 214                 /* compute the maxiumum number of functions a group can have */
 215                 max_functions += 1 << (desc_group->bit_width + 1);
 216         }
 217
 218         /* we will reallocate later */
 219         pctrl->functions = kcalloc(max_functions,
 220                                    sizeof(*pctrl->functions), GFP_KERNEL);
 221         if (!pctrl->functions)
 222                 return -ENOMEM;
 223
 224         /* register all functions */
 225         for (i = 0; i < pctrl->desc->ngroups; i++) {
 226                 desc_group = pctrl->desc->groups + i;
 227                 desc_function = desc_group->functions;
 228
 229                 while (desc_function->name) {
 230                         berlin_pinctrl_add_function(pctrl, desc_function->name);
 231                         desc_function++;
 232                 }
 233         }
 234
 235         pctrl->functions = krealloc(pctrl->functions,
 236                                     pctrl->nfunctions * sizeof(*pctrl->functions),
 237                                     GFP_KERNEL);
 238
 239         /* map functions to theirs groups */
 240         for (i = 0; i < pctrl->desc->ngroups; i++) {
 241                 desc_group = pctrl->desc->groups + i;
 242                 desc_function = desc_group->functions;
 243
 244                 while (desc_function->name) {
 245                         struct berlin_pinctrl_function
 246                                 *function = pctrl->functions;
 247                         const char **groups;
 248                         bool found = false;
 249
 250                         while (function->name) {
 251                                 if (!strcmp(desc_function->name, function->name)) {
 252                                         found = true;
 253                                         break;
 254                                 }
 255                                 function++;
 256                         }
 257
 258                         if (!found) {
 259                                 kfree(pctrl->functions);
 260                                 return -EINVAL;
 261                         }
 262
 263                         if (!function->groups) {
 264                                 function->groups =
 265                                         devm_kcalloc(&pdev->dev,
 266                                                      function->ngroups,
 267                                                      sizeof(char *),
 268                                                      GFP_KERNEL);
 269
 270                                 if (!function->groups) {
 271                                         kfree(pctrl->functions);
 272                                         return -ENOMEM;
 273                                 }
 274                         }
 275
 276                         groups = function->groups;
 277                         while (*groups)
 278                                 groups++;
 279
 280                         *groups = desc_group->name;
 281
 282                         desc_function++;
 283                 }
 284         }
 285
 286         return 0;
 287 }
 288
 289 static struct pinctrl_desc berlin_pctrl_desc = {
 290         .name           = "berlin-pinctrl",
 291         .pctlops        = &berlin_pinctrl_ops,
 292         .pmxops         = &berlin_pinmux_ops,
 293         .owner          = THIS_MODULE,
 294 };
 295
 296 int berlin_pinctrl_probe_regmap(struct platform_device *pdev,
 297                                 const struct berlin_pinctrl_desc *desc,
 298                                 struct regmap *regmap)
 299 {
 300         struct device *dev = &pdev->dev;
 301         struct berlin_pinctrl *pctrl;
 302         int ret;
 303
 304         pctrl = devm_kzalloc(dev, sizeof(*pctrl), GFP_KERNEL);
 305         if (!pctrl)
 306                 return -ENOMEM;
 307
 308         platform_set_drvdata(pdev, pctrl);
 309
 310         pctrl->regmap = regmap;
 311         pctrl->dev = &pdev->dev;
 312         pctrl->desc = desc;
 313
 314         ret = berlin_pinctrl_build_state(pdev);
 315         if (ret) {
 316                 dev_err(dev, "cannot build driver state: %d\n", ret);
 317                 return ret;
 318         }
 319
 320         pctrl->pctrl_dev = devm_pinctrl_register(dev, &berlin_pctrl_desc,
 321                                                  pctrl);
 322         if (IS_ERR(pctrl->pctrl_dev)) {
 323                 dev_err(dev, "failed to register pinctrl driver\n");
 324                 return PTR_ERR(pctrl->pctrl_dev);
 325         }
 326
 327         return 0;
 328 }
 329
 330 int berlin_pinctrl_probe(struct platform_device *pdev,
 331                          const struct berlin_pinctrl_desc *desc)
 332 {
 333         struct device *dev = &pdev->dev;
 334         struct device_node *parent_np = of_get_parent(dev->of_node);
 335         struct regmap *regmap = syscon_node_to_regmap(parent_np);
 336
 337         of_node_put(parent_np);
 338         if (IS_ERR(regmap))
 339                 return PTR_ERR(regmap);
 340
 341         return berlin_pinctrl_probe_regmap(pdev, desc, regmap);
 342 }