linux/drivers/pinctrl/zte/pinctrl-zx.c
<<
>>
Prefs
   1/*
   2 * Copyright (C) 2017 Sanechips Technology Co., Ltd.
   3 * Copyright 2017 Linaro Ltd.
   4 *
   5 * This program is free software; you can redistribute it and/or modify
   6 * it under the terms of the GNU General Public License version 2 as
   7 * published by the Free Software Foundation.
   8 */
   9
  10#include <linux/io.h>
  11#include <linux/of.h>
  12#include <linux/of_address.h>
  13#include <linux/of_device.h>
  14#include <linux/pinctrl/pinctrl.h>
  15#include <linux/pinctrl/pinconf-generic.h>
  16#include <linux/pinctrl/pinmux.h>
  17#include <linux/platform_device.h>
  18#include <linux/slab.h>
  19
  20#include "../core.h"
  21#include "../pinctrl-utils.h"
  22#include "../pinmux.h"
  23#include "pinctrl-zx.h"
  24
  25#define ZX_PULL_DOWN            BIT(0)
  26#define ZX_PULL_UP              BIT(1)
  27#define ZX_INPUT_ENABLE         BIT(3)
  28#define ZX_DS_SHIFT             4
  29#define ZX_DS_MASK              (0x7 << ZX_DS_SHIFT)
  30#define ZX_DS_VALUE(x)          (((x) << ZX_DS_SHIFT) & ZX_DS_MASK)
  31#define ZX_SLEW                 BIT(8)
  32
  33struct zx_pinctrl {
  34        struct pinctrl_dev *pctldev;
  35        struct device *dev;
  36        void __iomem *base;
  37        void __iomem *aux_base;
  38        spinlock_t lock;
  39        struct zx_pinctrl_soc_info *info;
  40};
  41
  42static int zx_dt_node_to_map(struct pinctrl_dev *pctldev,
  43                             struct device_node *np_config,
  44                             struct pinctrl_map **map, u32 *num_maps)
  45{
  46        return pinconf_generic_dt_node_to_map(pctldev, np_config, map,
  47                                              num_maps, PIN_MAP_TYPE_INVALID);
  48}
  49
  50static const struct pinctrl_ops zx_pinctrl_ops = {
  51        .dt_node_to_map = zx_dt_node_to_map,
  52        .dt_free_map = pinctrl_utils_free_map,
  53        .get_groups_count = pinctrl_generic_get_group_count,
  54        .get_group_name = pinctrl_generic_get_group_name,
  55        .get_group_pins = pinctrl_generic_get_group_pins,
  56};
  57
  58#define NONAON_MVAL 2
  59
  60static int zx_set_mux(struct pinctrl_dev *pctldev, unsigned int func_selector,
  61                      unsigned int group_selector)
  62{
  63        struct zx_pinctrl *zpctl = pinctrl_dev_get_drvdata(pctldev);
  64        struct zx_pinctrl_soc_info *info = zpctl->info;
  65        const struct pinctrl_pin_desc *pindesc = info->pins + group_selector;
  66        struct zx_pin_data *data = pindesc->drv_data;
  67        struct zx_mux_desc *mux;
  68        u32 mask, offset, bitpos;
  69        struct function_desc *func;
  70        unsigned long flags;
  71        u32 val, mval;
  72
  73        /* Skip reserved pin */
  74        if (!data)
  75                return -EINVAL;
  76
  77        mux = data->muxes;
  78        mask = (1 << data->width) - 1;
  79        offset = data->offset;
  80        bitpos = data->bitpos;
  81
  82        func = pinmux_generic_get_function(pctldev, func_selector);
  83        if (!func)
  84                return -EINVAL;
  85
  86        while (mux->name) {
  87                if (strcmp(mux->name, func->name) == 0)
  88                        break;
  89                mux++;
  90        }
  91
  92        /* Found mux value to be written */
  93        mval = mux->muxval;
  94
  95        spin_lock_irqsave(&zpctl->lock, flags);
  96
  97        if (data->aon_pin) {
  98                /*
  99                 * It's an AON pin, whose mux register offset and bit position
 100                 * can be caluculated from pin number.  Each register covers 16
 101                 * pins, and each pin occupies 2 bits.
 102                 */
 103                u16 aoffset = pindesc->number / 16 * 4;
 104                u16 abitpos = (pindesc->number % 16) * 2;
 105
 106                if (mval & AON_MUX_FLAG) {
 107                        /*
 108                         * This is a mux value that needs to be written into
 109                         * AON pinmux register.  Write it and then we're done.
 110                         */
 111                        val = readl(zpctl->aux_base + aoffset);
 112                        val &= ~(0x3 << abitpos);
 113                        val |= (mval & 0x3) << abitpos;
 114                        writel(val, zpctl->aux_base + aoffset);
 115                } else {
 116                        /*
 117                         * It's a mux value that needs to be written into TOP
 118                         * pinmux register.
 119                         */
 120                        val = readl(zpctl->base + offset);
 121                        val &= ~(mask << bitpos);
 122                        val |= (mval & mask) << bitpos;
 123                        writel(val, zpctl->base + offset);
 124
 125                        /*
 126                         * In this case, the AON pinmux register needs to be
 127                         * set up to select non-AON function.
 128                         */
 129                        val = readl(zpctl->aux_base + aoffset);
 130                        val &= ~(0x3 << abitpos);
 131                        val |= NONAON_MVAL << abitpos;
 132                        writel(val, zpctl->aux_base + aoffset);
 133                }
 134
 135        } else {
 136                /*
 137                 * This is a TOP pin, and we only need to set up TOP pinmux
 138                 * register and then we're done with it.
 139                 */
 140                val = readl(zpctl->base + offset);
 141                val &= ~(mask << bitpos);
 142                val |= (mval & mask) << bitpos;
 143                writel(val, zpctl->base + offset);
 144        }
 145
 146        spin_unlock_irqrestore(&zpctl->lock, flags);
 147
 148        return 0;
 149}
 150
 151static const struct pinmux_ops zx_pinmux_ops = {
 152        .get_functions_count = pinmux_generic_get_function_count,
 153        .get_function_name = pinmux_generic_get_function_name,
 154        .get_function_groups = pinmux_generic_get_function_groups,
 155        .set_mux = zx_set_mux,
 156};
 157
 158static int zx_pin_config_get(struct pinctrl_dev *pctldev, unsigned int pin,
 159                             unsigned long *config)
 160{
 161        struct zx_pinctrl *zpctl = pinctrl_dev_get_drvdata(pctldev);
 162        struct zx_pinctrl_soc_info *info = zpctl->info;
 163        const struct pinctrl_pin_desc *pindesc = info->pins + pin;
 164        struct zx_pin_data *data = pindesc->drv_data;
 165        enum pin_config_param param = pinconf_to_config_param(*config);
 166        u32 val;
 167
 168        /* Skip reserved pin */
 169        if (!data)
 170                return -EINVAL;
 171
 172        val = readl(zpctl->aux_base + data->coffset);
 173        val = val >> data->cbitpos;
 174
 175        switch (param) {
 176        case PIN_CONFIG_BIAS_PULL_DOWN:
 177                val &= ZX_PULL_DOWN;
 178                val = !!val;
 179                if (val == 0)
 180                        return -EINVAL;
 181                break;
 182        case PIN_CONFIG_BIAS_PULL_UP:
 183                val &= ZX_PULL_UP;
 184                val = !!val;
 185                if (val == 0)
 186                        return -EINVAL;
 187                break;
 188        case PIN_CONFIG_INPUT_ENABLE:
 189                val &= ZX_INPUT_ENABLE;
 190                val = !!val;
 191                if (val == 0)
 192                        return -EINVAL;
 193                break;
 194        case PIN_CONFIG_DRIVE_STRENGTH:
 195                val &= ZX_DS_MASK;
 196                val = val >> ZX_DS_SHIFT;
 197                break;
 198        case PIN_CONFIG_SLEW_RATE:
 199                val &= ZX_SLEW;
 200                val = !!val;
 201                break;
 202        default:
 203                return -ENOTSUPP;
 204        }
 205
 206        *config = pinconf_to_config_packed(param, val);
 207
 208        return 0;
 209}
 210
 211static int zx_pin_config_set(struct pinctrl_dev *pctldev, unsigned int pin,
 212                             unsigned long *configs, unsigned int num_configs)
 213{
 214        struct zx_pinctrl *zpctl = pinctrl_dev_get_drvdata(pctldev);
 215        struct zx_pinctrl_soc_info *info = zpctl->info;
 216        const struct pinctrl_pin_desc *pindesc = info->pins + pin;
 217        struct zx_pin_data *data = pindesc->drv_data;
 218        enum pin_config_param param;
 219        u32 val, arg;
 220        int i;
 221
 222        /* Skip reserved pin */
 223        if (!data)
 224                return -EINVAL;
 225
 226        val = readl(zpctl->aux_base + data->coffset);
 227
 228        for (i = 0; i < num_configs; i++) {
 229                param = pinconf_to_config_param(configs[i]);
 230                arg = pinconf_to_config_argument(configs[i]);
 231
 232                switch (param) {
 233                case PIN_CONFIG_BIAS_PULL_DOWN:
 234                        val |= ZX_PULL_DOWN << data->cbitpos;
 235                        break;
 236                case PIN_CONFIG_BIAS_PULL_UP:
 237                        val |= ZX_PULL_UP << data->cbitpos;
 238                        break;
 239                case PIN_CONFIG_INPUT_ENABLE:
 240                        val |= ZX_INPUT_ENABLE << data->cbitpos;
 241                        break;
 242                case PIN_CONFIG_DRIVE_STRENGTH:
 243                        val &= ~(ZX_DS_MASK << data->cbitpos);
 244                        val |= ZX_DS_VALUE(arg) << data->cbitpos;
 245                        break;
 246                case PIN_CONFIG_SLEW_RATE:
 247                        if (arg)
 248                                val |= ZX_SLEW << data->cbitpos;
 249                        else
 250                                val &= ~ZX_SLEW << data->cbitpos;
 251                        break;
 252                default:
 253                        return -ENOTSUPP;
 254                }
 255        }
 256
 257        writel(val, zpctl->aux_base + data->coffset);
 258        return 0;
 259}
 260
 261static const struct pinconf_ops zx_pinconf_ops = {
 262        .pin_config_set = zx_pin_config_set,
 263        .pin_config_get = zx_pin_config_get,
 264        .is_generic = true,
 265};
 266
 267static int zx_pinctrl_build_state(struct platform_device *pdev)
 268{
 269        struct zx_pinctrl *zpctl = platform_get_drvdata(pdev);
 270        struct zx_pinctrl_soc_info *info = zpctl->info;
 271        struct pinctrl_dev *pctldev = zpctl->pctldev;
 272        struct function_desc *functions;
 273        int nfunctions;
 274        struct group_desc *groups;
 275        int ngroups;
 276        int i;
 277
 278        /* Every single pin composes a group */
 279        ngroups = info->npins;
 280        groups = devm_kzalloc(&pdev->dev, ngroups * sizeof(*groups),
 281                              GFP_KERNEL);
 282        if (!groups)
 283                return -ENOMEM;
 284
 285        for (i = 0; i < ngroups; i++) {
 286                const struct pinctrl_pin_desc *pindesc = info->pins + i;
 287                struct group_desc *group = groups + i;
 288
 289                group->name = pindesc->name;
 290                group->pins = (int *) &pindesc->number;
 291                group->num_pins = 1;
 292                radix_tree_insert(&pctldev->pin_group_tree, i, group);
 293        }
 294
 295        pctldev->num_groups = ngroups;
 296
 297        /* Build function list from pin mux functions */
 298        functions = kcalloc(info->npins, sizeof(*functions), GFP_KERNEL);
 299        if (!functions)
 300                return -ENOMEM;
 301
 302        nfunctions = 0;
 303        for (i = 0; i < info->npins; i++) {
 304                const struct pinctrl_pin_desc *pindesc = info->pins + i;
 305                struct zx_pin_data *data = pindesc->drv_data;
 306                struct zx_mux_desc *mux;
 307
 308                /* Reserved pins do not have a drv_data at all */
 309                if (!data)
 310                        continue;
 311
 312                /* Loop over all muxes for the pin */
 313                mux = data->muxes;
 314                while (mux->name) {
 315                        struct function_desc *func = functions;
 316
 317                        /* Search function list for given mux */
 318                        while (func->name) {
 319                                if (strcmp(mux->name, func->name) == 0) {
 320                                        /* Function exists */
 321                                        func->num_group_names++;
 322                                        break;
 323                                }
 324                                func++;
 325                        }
 326
 327                        if (!func->name) {
 328                                /* New function */
 329                                func->name = mux->name;
 330                                func->num_group_names = 1;
 331                                radix_tree_insert(&pctldev->pin_function_tree,
 332                                                  nfunctions++, func);
 333                        }
 334
 335                        mux++;
 336                }
 337        }
 338
 339        pctldev->num_functions = nfunctions;
 340        functions = krealloc(functions, nfunctions * sizeof(*functions),
 341                             GFP_KERNEL);
 342
 343        /* Find pin groups for every single function */
 344        for (i = 0; i < info->npins; i++) {
 345                const struct pinctrl_pin_desc *pindesc = info->pins + i;
 346                struct zx_pin_data *data = pindesc->drv_data;
 347                struct zx_mux_desc *mux;
 348
 349                if (!data)
 350                        continue;
 351
 352                mux = data->muxes;
 353                while (mux->name) {
 354                        struct function_desc *func;
 355                        const char **group;
 356                        int j;
 357
 358                        /* Find function for given mux */
 359                        for (j = 0; j < nfunctions; j++)
 360                                if (strcmp(functions[j].name, mux->name) == 0)
 361                                        break;
 362
 363                        func = functions + j;
 364                        if (!func->group_names) {
 365                                func->group_names = devm_kzalloc(&pdev->dev,
 366                                                func->num_group_names *
 367                                                sizeof(*func->group_names),
 368                                                GFP_KERNEL);
 369                                if (!func->group_names) {
 370                                        kfree(functions);
 371                                        return -ENOMEM;
 372                                }
 373                        }
 374
 375                        group = func->group_names;
 376                        while (*group)
 377                                group++;
 378                        *group = pindesc->name;
 379
 380                        mux++;
 381                }
 382        }
 383
 384        return 0;
 385}
 386
 387int zx_pinctrl_init(struct platform_device *pdev,
 388                    struct zx_pinctrl_soc_info *info)
 389{
 390        struct pinctrl_desc *pctldesc;
 391        struct zx_pinctrl *zpctl;
 392        struct device_node *np;
 393        struct resource *res;
 394        int ret;
 395
 396        zpctl = devm_kzalloc(&pdev->dev, sizeof(*zpctl), GFP_KERNEL);
 397        if (!zpctl)
 398                return -ENOMEM;
 399
 400        spin_lock_init(&zpctl->lock);
 401
 402        res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 403        zpctl->base = devm_ioremap_resource(&pdev->dev, res);
 404        if (IS_ERR(zpctl->base))
 405                return PTR_ERR(zpctl->base);
 406
 407        np = of_parse_phandle(pdev->dev.of_node, "zte,auxiliary-controller", 0);
 408        if (!np) {
 409                dev_err(&pdev->dev, "failed to find auxiliary controller\n");
 410                return -ENODEV;
 411        }
 412
 413        zpctl->aux_base = of_iomap(np, 0);
 414        if (!zpctl->aux_base)
 415                return -ENOMEM;
 416
 417        zpctl->dev = &pdev->dev;
 418        zpctl->info = info;
 419
 420        pctldesc = devm_kzalloc(&pdev->dev, sizeof(*pctldesc), GFP_KERNEL);
 421        if (!pctldesc)
 422                return -ENOMEM;
 423
 424        pctldesc->name = dev_name(&pdev->dev);
 425        pctldesc->owner = THIS_MODULE;
 426        pctldesc->pins = info->pins;
 427        pctldesc->npins = info->npins;
 428        pctldesc->pctlops = &zx_pinctrl_ops;
 429        pctldesc->pmxops = &zx_pinmux_ops;
 430        pctldesc->confops = &zx_pinconf_ops;
 431
 432        zpctl->pctldev = devm_pinctrl_register(&pdev->dev, pctldesc, zpctl);
 433        if (IS_ERR(zpctl->pctldev)) {
 434                ret = PTR_ERR(zpctl->pctldev);
 435                dev_err(&pdev->dev, "failed to register pinctrl: %d\n", ret);
 436                return ret;
 437        }
 438
 439        platform_set_drvdata(pdev, zpctl);
 440
 441        ret = zx_pinctrl_build_state(pdev);
 442        if (ret) {
 443                dev_err(&pdev->dev, "failed to build state: %d\n", ret);
 444                return ret;
 445        }
 446
 447        dev_info(&pdev->dev, "initialized pinctrl driver\n");
 448        return 0;
 449}
 450