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