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 0;
 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_group *mux = p->groups;
 197         int i, j, c = 0;
 198
 199         /* count the mux functions */
 200         while (mux->name) {
 201                 p->group_count++;
 202                 mux++;
 203         }
 204
 205         /* allocate the group names array needed by the gpio function */
 206         p->group_names = devm_kcalloc(p->dev, p->group_count,
 207                                       sizeof(char *), GFP_KERNEL);
 208         if (!p->group_names)
 209                 return -ENOMEM;
 210
 211         for (i = 0; i < p->group_count; i++) {
 212                 p->group_names[i] = p->groups[i].name;
 213                 p->func_count += p->groups[i].func_count;
 214         }
 215
 216         /* we have a dummy function[0] for gpio */
 217         p->func_count++;
 218
 219         /* allocate our function and group mapping index buffers */
 220         p->func = devm_kcalloc(p->dev, p->func_count,
 221                                sizeof(*p->func), GFP_KERNEL);
 222         gpio_func.groups = devm_kcalloc(p->dev, p->group_count, sizeof(int),
 223                                         GFP_KERNEL);
 224         if (!p->func || !gpio_func.groups)
 225                 return -ENOMEM;
 226
 227         /* add a backpointer to the function so it knows its group */
 228         gpio_func.group_count = p->group_count;
 229         for (i = 0; i < gpio_func.group_count; i++)
 230                 gpio_func.groups[i] = i;
 231
 232         p->func[c] = &gpio_func;
 233         c++;
 234
 235         /* add remaining functions */
 236         for (i = 0; i < p->group_count; i++) {
 237                 for (j = 0; j < p->groups[i].func_count; j++) {
 238                         p->func[c] = &p->groups[i].func[j];
 239                         p->func[c]->groups = devm_kzalloc(p->dev, sizeof(int),
 240                                                     GFP_KERNEL);
 241                         if (!p->func[c]->groups)
 242                                 return -ENOMEM;
 243                         p->func[c]->groups[0] = i;
 244                         p->func[c]->group_count = 1;
 245                         c++;
 246                 }
 247         }
 248         return 0;
 249 }
 250
 251 static int rt2880_pinmux_pins(struct rt2880_priv *p)
 252 {
 253         int i, j;
 254
 255         /*
 256          * loop over the functions and initialize the pins array.
 257          * also work out the highest pin used.
 258          */
 259         for (i = 0; i < p->func_count; i++) {
 260                 int pin;
 261
 262                 if (!p->func[i]->pin_count)
 263                         continue;
 264
 265                 p->func[i]->pins = devm_kcalloc(p->dev,
 266                                                 p->func[i]->pin_count,
 267                                                 sizeof(int),
 268                                                 GFP_KERNEL);
 269                 for (j = 0; j < p->func[i]->pin_count; j++)
 270                         p->func[i]->pins[j] = p->func[i]->pin_first + j;
 271
 272                 pin = p->func[i]->pin_first + p->func[i]->pin_count;
 273                 if (pin > p->max_pins)
 274                         p->max_pins = pin;
 275         }
 276
 277         /* the buffer that tells us which pins are gpio */
 278         p->gpio = devm_kcalloc(p->dev, p->max_pins, sizeof(u8), GFP_KERNEL);
 279         /* the pads needed to tell pinctrl about our pins */
 280         p->pads = devm_kcalloc(p->dev, p->max_pins,
 281                                sizeof(struct pinctrl_pin_desc), GFP_KERNEL);
 282         if (!p->pads || !p->gpio)
 283                 return -ENOMEM;
 284
 285         memset(p->gpio, 1, sizeof(u8) * p->max_pins);
 286         for (i = 0; i < p->func_count; i++) {
 287                 if (!p->func[i]->pin_count)
 288                         continue;
 289
 290                 for (j = 0; j < p->func[i]->pin_count; j++)
 291                         p->gpio[p->func[i]->pins[j]] = 0;
 292         }
 293
 294         /* pin 0 is always a gpio */
 295         p->gpio[0] = 1;
 296
 297         /* set the pads */
 298         for (i = 0; i < p->max_pins; i++) {
 299                 /* strlen("ioXY") + 1 = 5 */
 300                 char *name = devm_kzalloc(p->dev, 5, GFP_KERNEL);
 301
 302                 if (!name)
 303                         return -ENOMEM;
 304                 snprintf(name, 5, "io%d", i);
 305                 p->pads[i].number = i;
 306                 p->pads[i].name = name;
 307         }
 308         p->desc->pins = p->pads;
 309         p->desc->npins = p->max_pins;
 310
 311         return 0;
 312 }
 313
 314 static int rt2880_pinmux_probe(struct platform_device *pdev)
 315 {
 316         struct rt2880_priv *p;
 317         struct pinctrl_dev *dev;
 318         int err;
 319
 320         if (!rt2880_pinmux_data)
 321                 return -ENOTSUPP;
 322
 323         /* setup the private data */
 324         p = devm_kzalloc(&pdev->dev, sizeof(struct rt2880_priv), GFP_KERNEL);
 325         if (!p)
 326                 return -ENOMEM;
 327
 328         p->dev = &pdev->dev;
 329         p->desc = &rt2880_pctrl_desc;
 330         p->groups = rt2880_pinmux_data;
 331         platform_set_drvdata(pdev, p);
 332
 333         /* init the device */
 334         err = rt2880_pinmux_index(p);
 335         if (err) {
 336                 dev_err(&pdev->dev, "failed to load index\n");
 337                 return err;
 338         }
 339
 340         err = rt2880_pinmux_pins(p);
 341         if (err) {
 342                 dev_err(&pdev->dev, "failed to load pins\n");
 343                 return err;
 344         }
 345         dev = pinctrl_register(p->desc, &pdev->dev, p);
 346
 347         return PTR_ERR_OR_ZERO(dev);
 348 }
 349
 350 static const struct of_device_id rt2880_pinmux_match[] = {
 351         { .compatible = "ralink,rt2880-pinmux" },
 352         {},
 353 };
 354 MODULE_DEVICE_TABLE(of, rt2880_pinmux_match);
 355
 356 static struct platform_driver rt2880_pinmux_driver = {
 357         .probe = rt2880_pinmux_probe,
 358         .driver = {
 359                 .name = "rt2880-pinmux",
 360                 .of_match_table = rt2880_pinmux_match,
 361         },
 362 };
 363
 364 static int __init rt2880_pinmux_init(void)
 365 {
 366         return platform_driver_register(&rt2880_pinmux_driver);
 367 }
 368
 369 core_initcall_sync(rt2880_pinmux_init);