drivers/staging/mt7621-pinctrl/pinctrl-rt2880.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  *  Copyright (C) 2013 John Crispin <blogic@openwrt.org>
   4  */
   5
   6 #include <linux/module.h>
   7 #include <linux/device.h>
   8 #include <linux/io.h>
   9 #include <linux/platform_device.h>
  10 #include <linux/slab.h>
  11 #include <linux/of.h>
  12 #include <linux/pinctrl/pinctrl.h>
  13 #include <linux/pinctrl/pinconf.h>
  14 #include <linux/pinctrl/pinmux.h>
  15 #include <linux/pinctrl/consumer.h>
  16 #include <linux/pinctrl/machine.h>
  17
  18 #include <asm/mach-ralink/ralink_regs.h>
  19 #include <asm/mach-ralink/pinmux.h>
  20 #include <asm/mach-ralink/mt7620.h>
  21
  22 #include "core.h"
  23 #include "pinctrl-utils.h"
  24
  25 #define SYSC_REG_GPIO_MODE      0x60
  26 #define SYSC_REG_GPIO_MODE2     0x64
  27
  28 struct rt2880_priv {
  29         struct device *dev;
  30
  31         struct pinctrl_pin_desc *pads;
  32         struct pinctrl_desc *desc;
  33
  34         struct rt2880_pmx_func **func;
  35         int func_count;
  36
  37         struct rt2880_pmx_group *groups;
  38         const char **group_names;
  39         int group_count;
  40
  41         u8 *gpio;
  42         int max_pins;
  43 };
  44
  45 static int rt2880_get_group_count(struct pinctrl_dev *pctrldev)
  46 {
  47         struct rt2880_priv *p = pinctrl_dev_get_drvdata(pctrldev);
  48
  49         return p->group_count;
  50 }
  51
  52 static const char *rt2880_get_group_name(struct pinctrl_dev *pctrldev,
  53                                          unsigned int group)
  54 {
  55         struct rt2880_priv *p = pinctrl_dev_get_drvdata(pctrldev);
  56
  57         return (group >= p->group_count) ? NULL : p->group_names[group];
  58 }
  59
  60 static int rt2880_get_group_pins(struct pinctrl_dev *pctrldev,
  61                                  unsigned int group,
  62                                  const unsigned int **pins,
  63                                  unsigned int *num_pins)
  64 {
  65         struct rt2880_priv *p = pinctrl_dev_get_drvdata(pctrldev);
  66
  67         if (group >= p->group_count)
  68                 return -EINVAL;
  69
  70         *pins = p->groups[group].func[0].pins;
  71         *num_pins = p->groups[group].func[0].pin_count;
  72
  73         return 0;
  74 }
  75
  76 static int rt2880_pinctrl_dt_node_to_map(struct pinctrl_dev *pctrldev,
  77                                          struct device_node *np_config,
  78                                          struct pinctrl_map **map,
  79                                          unsigned int *num_maps)
  80 {
  81         struct rt2880_priv *p = pinctrl_dev_get_drvdata(pctrldev);
  82         struct property *prop;
  83         const char *function_name, *group_name;
  84         int ret;
  85         int ngroups = 0;
  86         unsigned int reserved_maps = 0;
  87
  88         for_each_node_with_property(np_config, "group")
  89                 ngroups++;
  90
  91         *map = NULL;
  92         ret = pinctrl_utils_reserve_map(pctrldev, map, &reserved_maps,
  93                                         num_maps, ngroups);
  94         if (ret) {
  95                 dev_err(p->dev, "can't reserve map: %d\n", ret);
  96                 return ret;
  97         }
  98
  99         of_property_for_each_string(np_config, "group", prop, group_name) {
 100                 ret = pinctrl_utils_add_map_mux(pctrldev, map, &reserved_maps,
 101                                                 num_maps, group_name,
 102                                                 function_name);
 103                 if (ret) {
 104                         dev_err(p->dev, "can't add map: %d\n", ret);
 105                         return ret;
 106                 }
 107         }
 108
 109         return 0;
 110 }
 111
 112 static const struct pinctrl_ops rt2880_pctrl_ops = {
 113         .get_groups_count       = rt2880_get_group_count,
 114         .get_group_name         = rt2880_get_group_name,
 115         .get_group_pins         = rt2880_get_group_pins,
 116         .dt_node_to_map         = rt2880_pinctrl_dt_node_to_map,
 117         .dt_free_map            = pinctrl_utils_free_map,
 118 };
 119
 120 static int rt2880_pmx_func_count(struct pinctrl_dev *pctrldev)
 121 {
 122         struct rt2880_priv *p = pinctrl_dev_get_drvdata(pctrldev);
 123
 124         return p->func_count;
 125 }
 126
 127 static const char *rt2880_pmx_func_name(struct pinctrl_dev *pctrldev,
 128                                         unsigned int func)
 129 {
 130         struct rt2880_priv *p = pinctrl_dev_get_drvdata(pctrldev);
 131
 132         return p->func[func]->name;
 133 }
 134
 135 static int rt2880_pmx_group_get_groups(struct pinctrl_dev *pctrldev,
 136                                        unsigned int func,
 137                                        const char * const **groups,
 138                                        unsigned int * const num_groups)
 139 {
 140         struct rt2880_priv *p = pinctrl_dev_get_drvdata(pctrldev);
 141
 142         if (p->func[func]->group_count == 1)
 143                 *groups = &p->group_names[p->func[func]->groups[0]];
 144         else
 145                 *groups = p->group_names;
 146
 147         *num_groups = p->func[func]->group_count;
 148
 149         return 0;
 150 }
 151
 152 static int rt2880_pmx_group_enable(struct pinctrl_dev *pctrldev,
 153                                    unsigned int func, unsigned int group)
 154 {
 155         struct rt2880_priv *p = pinctrl_dev_get_drvdata(pctrldev);
 156         u32 mode = 0;
 157         u32 reg = SYSC_REG_GPIO_MODE;
 158         int i;
 159         int shift;
 160
 161         /* dont allow double use */
 162         if (p->groups[group].enabled) {
 163                 dev_err(p->dev, "%s is already enabled\n",
 164                         p->groups[group].name);
 165                 return -EBUSY;
 166         }
 167
 168         p->groups[group].enabled = 1;
 169         p->func[func]->enabled = 1;
 170
 171         shift = p->groups[group].shift;
 172         if (shift >= 32) {
 173                 shift -= 32;
 174                 reg = SYSC_REG_GPIO_MODE2;
 175         }
 176         mode = rt_sysc_r32(reg);
 177         mode &= ~(p->groups[group].mask << shift);
 178
 179         /* mark the pins as gpio */
 180         for (i = 0; i < p->groups[group].func[0].pin_count; i++)
 181                 p->gpio[p->groups[group].func[0].pins[i]] = 1;
 182
 183         /* function 0 is gpio and needs special handling */
 184         if (func == 0) {
 185                 mode |= p->groups[group].gpio << shift;
 186         } else {
 187                 for (i = 0; i < p->func[func]->pin_count; i++)
 188                         p->gpio[p->func[func]->pins[i]] = 0;
 189                 mode |= p->func[func]->value << shift;
 190         }
 191         rt_sysc_w32(mode, reg);
 192
 193         return 0;
 194 }
 195
 196 static int rt2880_pmx_group_gpio_request_enable(struct pinctrl_dev *pctrldev,
 197                                                 struct pinctrl_gpio_range *range,
 198                                                 unsigned int pin)
 199 {
 200         struct rt2880_priv *p = pinctrl_dev_get_drvdata(pctrldev);
 201
 202         if (!p->gpio[pin]) {
 203                 dev_err(p->dev, "pin %d is not set to gpio mux\n", pin);
 204                 return -EINVAL;
 205         }
 206
 207         return 0;
 208 }
 209
 210 static const struct pinmux_ops rt2880_pmx_group_ops = {
 211         .get_functions_count    = rt2880_pmx_func_count,
 212         .get_function_name      = rt2880_pmx_func_name,
 213         .get_function_groups    = rt2880_pmx_group_get_groups,
 214         .set_mux                = rt2880_pmx_group_enable,
 215         .gpio_request_enable    = rt2880_pmx_group_gpio_request_enable,
 216 };
 217
 218 static struct pinctrl_desc rt2880_pctrl_desc = {
 219         .owner          = THIS_MODULE,
 220         .name           = "rt2880-pinmux",
 221         .pctlops        = &rt2880_pctrl_ops,
 222         .pmxops         = &rt2880_pmx_group_ops,
 223 };
 224
 225 static struct rt2880_pmx_func gpio_func = {
 226         .name = "gpio",
 227 };
 228
 229 static int rt2880_pinmux_index(struct rt2880_priv *p)
 230 {
 231         struct rt2880_pmx_func **f;
 232         struct rt2880_pmx_group *mux = p->groups;
 233         int i, j, c = 0;
 234
 235         /* count the mux functions */
 236         while (mux->name) {
 237                 p->group_count++;
 238                 mux++;
 239         }
 240
 241         /* allocate the group names array needed by the gpio function */
 242         p->group_names = devm_kcalloc(p->dev, p->group_count,
 243                                       sizeof(char *), GFP_KERNEL);
 244         if (!p->group_names)
 245                 return -1;
 246
 247         for (i = 0; i < p->group_count; i++) {
 248                 p->group_names[i] = p->groups[i].name;
 249                 p->func_count += p->groups[i].func_count;
 250         }
 251
 252         /* we have a dummy function[0] for gpio */
 253         p->func_count++;
 254
 255         /* allocate our function and group mapping index buffers */
 256         f = p->func = devm_kcalloc(p->dev,
 257                                    p->func_count,
 258                                    sizeof(struct rt2880_pmx_func),
 259                                    GFP_KERNEL);
 260         gpio_func.groups = devm_kcalloc(p->dev, p->group_count, sizeof(int),
 261                                         GFP_KERNEL);
 262         if (!f || !gpio_func.groups)
 263                 return -1;
 264
 265         /* add a backpointer to the function so it knows its group */
 266         gpio_func.group_count = p->group_count;
 267         for (i = 0; i < gpio_func.group_count; i++)
 268                 gpio_func.groups[i] = i;
 269
 270         f[c] = &gpio_func;
 271         c++;
 272
 273         /* add remaining functions */
 274         for (i = 0; i < p->group_count; i++) {
 275                 for (j = 0; j < p->groups[i].func_count; j++) {
 276                         f[c] = &p->groups[i].func[j];
 277                         f[c]->groups = devm_kzalloc(p->dev, sizeof(int),
 278                                                     GFP_KERNEL);
 279                         f[c]->groups[0] = i;
 280                         f[c]->group_count = 1;
 281                         c++;
 282                 }
 283         }
 284         return 0;
 285 }
 286
 287 static int rt2880_pinmux_pins(struct rt2880_priv *p)
 288 {
 289         int i, j;
 290
 291         /*
 292          * loop over the functions and initialize the pins array.
 293          * also work out the highest pin used.
 294          */
 295         for (i = 0; i < p->func_count; i++) {
 296                 int pin;
 297
 298                 if (!p->func[i]->pin_count)
 299                         continue;
 300
 301                 p->func[i]->pins = devm_kcalloc(p->dev,
 302                                                 p->func[i]->pin_count,
 303                                                 sizeof(int),
 304                                                 GFP_KERNEL);
 305                 for (j = 0; j < p->func[i]->pin_count; j++)
 306                         p->func[i]->pins[j] = p->func[i]->pin_first + j;
 307
 308                 pin = p->func[i]->pin_first + p->func[i]->pin_count;
 309                 if (pin > p->max_pins)
 310                         p->max_pins = pin;
 311         }
 312
 313         /* the buffer that tells us which pins are gpio */
 314         p->gpio = devm_kcalloc(p->dev, p->max_pins, sizeof(u8), GFP_KERNEL);
 315         /* the pads needed to tell pinctrl about our pins */
 316         p->pads = devm_kcalloc(p->dev, p->max_pins,
 317                                sizeof(struct pinctrl_pin_desc), GFP_KERNEL);
 318         if (!p->pads || !p->gpio) {
 319                 dev_err(p->dev, "Failed to allocate gpio data\n");
 320                 return -ENOMEM;
 321         }
 322
 323         memset(p->gpio, 1, sizeof(u8) * p->max_pins);
 324         for (i = 0; i < p->func_count; i++) {
 325                 if (!p->func[i]->pin_count)
 326                         continue;
 327
 328                 for (j = 0; j < p->func[i]->pin_count; j++)
 329                         p->gpio[p->func[i]->pins[j]] = 0;
 330         }
 331
 332         /* pin 0 is always a gpio */
 333         p->gpio[0] = 1;
 334
 335         /* set the pads */
 336         for (i = 0; i < p->max_pins; i++) {
 337                 /* strlen("ioXY") + 1 = 5 */
 338                 char *name = devm_kzalloc(p->dev, 5, GFP_KERNEL);
 339
 340                 if (!name)
 341                         return -ENOMEM;
 342                 snprintf(name, 5, "io%d", i);
 343                 p->pads[i].number = i;
 344                 p->pads[i].name = name;
 345         }
 346         p->desc->pins = p->pads;
 347         p->desc->npins = p->max_pins;
 348
 349         return 0;
 350 }
 351
 352 static int rt2880_pinmux_probe(struct platform_device *pdev)
 353 {
 354         struct rt2880_priv *p;
 355         struct pinctrl_dev *dev;
 356         struct device_node *np;
 357
 358         if (!rt2880_pinmux_data)
 359                 return -ENOTSUPP;
 360
 361         /* setup the private data */
 362         p = devm_kzalloc(&pdev->dev, sizeof(struct rt2880_priv), GFP_KERNEL);
 363         if (!p)
 364                 return -ENOMEM;
 365
 366         p->dev = &pdev->dev;
 367         p->desc = &rt2880_pctrl_desc;
 368         p->groups = rt2880_pinmux_data;
 369         platform_set_drvdata(pdev, p);
 370
 371         /* init the device */
 372         if (rt2880_pinmux_index(p)) {
 373                 dev_err(&pdev->dev, "failed to load index\n");
 374                 return -EINVAL;
 375         }
 376         if (rt2880_pinmux_pins(p)) {
 377                 dev_err(&pdev->dev, "failed to load pins\n");
 378                 return -EINVAL;
 379         }
 380         dev = pinctrl_register(p->desc, &pdev->dev, p);
 381         if (IS_ERR(dev))
 382                 return PTR_ERR(dev);
 383
 384         /* finalize by adding gpio ranges for enables gpio controllers */
 385         for_each_compatible_node(np, NULL, "ralink,rt2880-gpio") {
 386                 const __be32 *ngpio, *gpiobase;
 387                 struct pinctrl_gpio_range *range;
 388                 char *name;
 389
 390                 if (!of_device_is_available(np))
 391                         continue;
 392
 393                 ngpio = of_get_property(np, "ralink,num-gpios", NULL);
 394                 gpiobase = of_get_property(np, "ralink,gpio-base", NULL);
 395                 if (!ngpio || !gpiobase) {
 396                         dev_err(&pdev->dev, "failed to load chip info\n");
 397                         return -EINVAL;
 398                 }
 399
 400                 range = devm_kzalloc(p->dev, sizeof(*range) + 4, GFP_KERNEL);
 401                 range->name = name = (char *) &range[1];
 402                 sprintf(name, "pio");
 403                 range->npins = __be32_to_cpu(*ngpio);
 404                 range->base = __be32_to_cpu(*gpiobase);
 405                 range->pin_base = range->base;
 406                 pinctrl_add_gpio_range(dev, range);
 407         }
 408
 409         return 0;
 410 }
 411
 412 static const struct of_device_id rt2880_pinmux_match[] = {
 413         { .compatible = "ralink,rt2880-pinmux" },
 414         {},
 415 };
 416 MODULE_DEVICE_TABLE(of, rt2880_pinmux_match);
 417
 418 static struct platform_driver rt2880_pinmux_driver = {
 419         .probe = rt2880_pinmux_probe,
 420         .driver = {
 421                 .name = "rt2880-pinmux",
 422                 .of_match_table = rt2880_pinmux_match,
 423         },
 424 };
 425
 426 int __init rt2880_pinmux_init(void)
 427 {
 428         return platform_driver_register(&rt2880_pinmux_driver);
 429 }
 430
 431 core_initcall_sync(rt2880_pinmux_init);