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