linux/drivers/pinctrl/ralink/pinctrl-rt2880.c
<<
>>
Prefs
   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/mt7620.h>
  21
  22#include "pinmux.h"
  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
  29struct 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
  46static 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
  53static 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
  61static 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
  77static 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
  85static 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
  92static 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
 100static 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
 117static 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
 161static 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
 175static 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
 183static 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
 190static struct rt2880_pmx_func gpio_func = {
 191        .name = "gpio",
 192};
 193
 194static 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
 251static 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
 314int rt2880_pinmux_init(struct platform_device *pdev,
 315                       struct rt2880_pmx_group *data)
 316{
 317        struct rt2880_priv *p;
 318        struct pinctrl_dev *dev;
 319        int err;
 320
 321        if (!data)
 322                return -ENOTSUPP;
 323
 324        /* setup the private data */
 325        p = devm_kzalloc(&pdev->dev, sizeof(struct rt2880_priv), GFP_KERNEL);
 326        if (!p)
 327                return -ENOMEM;
 328
 329        p->dev = &pdev->dev;
 330        p->desc = &rt2880_pctrl_desc;
 331        p->groups = data;
 332        platform_set_drvdata(pdev, p);
 333
 334        /* init the device */
 335        err = rt2880_pinmux_index(p);
 336        if (err) {
 337                dev_err(&pdev->dev, "failed to load index\n");
 338                return err;
 339        }
 340
 341        err = rt2880_pinmux_pins(p);
 342        if (err) {
 343                dev_err(&pdev->dev, "failed to load pins\n");
 344                return err;
 345        }
 346        dev = pinctrl_register(p->desc, &pdev->dev, p);
 347
 348        return PTR_ERR_OR_ZERO(dev);
 349}
 350