linux/drivers/pinctrl/spear/pinctrl-spear.c
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   1/*
   2 * Driver for the ST Microelectronics SPEAr pinmux
   3 *
   4 * Copyright (C) 2012 ST Microelectronics
   5 * Viresh Kumar <vireshk@kernel.org>
   6 *
   7 * Inspired from:
   8 * - U300 Pinctl drivers
   9 * - Tegra Pinctl drivers
  10 *
  11 * This file is licensed under the terms of the GNU General Public
  12 * License version 2. This program is licensed "as is" without any
  13 * warranty of any kind, whether express or implied.
  14 */
  15
  16#include <linux/err.h>
  17#include <linux/module.h>
  18#include <linux/of.h>
  19#include <linux/of_address.h>
  20#include <linux/of_gpio.h>
  21#include <linux/pinctrl/machine.h>
  22#include <linux/pinctrl/pinctrl.h>
  23#include <linux/pinctrl/pinmux.h>
  24#include <linux/platform_device.h>
  25#include <linux/slab.h>
  26
  27#include "pinctrl-spear.h"
  28
  29#define DRIVER_NAME "spear-pinmux"
  30
  31static void muxregs_endisable(struct spear_pmx *pmx,
  32                struct spear_muxreg *muxregs, u8 count, bool enable)
  33{
  34        struct spear_muxreg *muxreg;
  35        u32 val, temp, j;
  36
  37        for (j = 0; j < count; j++) {
  38                muxreg = &muxregs[j];
  39
  40                val = pmx_readl(pmx, muxreg->reg);
  41                val &= ~muxreg->mask;
  42
  43                if (enable)
  44                        temp = muxreg->val;
  45                else
  46                        temp = ~muxreg->val;
  47
  48                val |= muxreg->mask & temp;
  49                pmx_writel(pmx, val, muxreg->reg);
  50        }
  51}
  52
  53static int set_mode(struct spear_pmx *pmx, int mode)
  54{
  55        struct spear_pmx_mode *pmx_mode = NULL;
  56        int i;
  57        u32 val;
  58
  59        if (!pmx->machdata->pmx_modes || !pmx->machdata->npmx_modes)
  60                return -EINVAL;
  61
  62        for (i = 0; i < pmx->machdata->npmx_modes; i++) {
  63                if (pmx->machdata->pmx_modes[i]->mode == (1 << mode)) {
  64                        pmx_mode = pmx->machdata->pmx_modes[i];
  65                        break;
  66                }
  67        }
  68
  69        if (!pmx_mode)
  70                return -EINVAL;
  71
  72        val = pmx_readl(pmx, pmx_mode->reg);
  73        val &= ~pmx_mode->mask;
  74        val |= pmx_mode->val;
  75        pmx_writel(pmx, val, pmx_mode->reg);
  76
  77        pmx->machdata->mode = pmx_mode->mode;
  78        dev_info(pmx->dev, "Configured Mode: %s with id: %x\n\n",
  79                        pmx_mode->name ? pmx_mode->name : "no_name",
  80                        pmx_mode->reg);
  81
  82        return 0;
  83}
  84
  85void pmx_init_gpio_pingroup_addr(struct spear_gpio_pingroup *gpio_pingroup,
  86                                 unsigned count, u16 reg)
  87{
  88        int i, j;
  89
  90        for (i = 0; i < count; i++)
  91                for (j = 0; j < gpio_pingroup[i].nmuxregs; j++)
  92                        gpio_pingroup[i].muxregs[j].reg = reg;
  93}
  94
  95void pmx_init_addr(struct spear_pinctrl_machdata *machdata, u16 reg)
  96{
  97        struct spear_pingroup *pgroup;
  98        struct spear_modemux *modemux;
  99        int i, j, group;
 100
 101        for (group = 0; group < machdata->ngroups; group++) {
 102                pgroup = machdata->groups[group];
 103
 104                for (i = 0; i < pgroup->nmodemuxs; i++) {
 105                        modemux = &pgroup->modemuxs[i];
 106
 107                        for (j = 0; j < modemux->nmuxregs; j++)
 108                                if (modemux->muxregs[j].reg == 0xFFFF)
 109                                        modemux->muxregs[j].reg = reg;
 110                }
 111        }
 112}
 113
 114static int spear_pinctrl_get_groups_cnt(struct pinctrl_dev *pctldev)
 115{
 116        struct spear_pmx *pmx = pinctrl_dev_get_drvdata(pctldev);
 117
 118        return pmx->machdata->ngroups;
 119}
 120
 121static const char *spear_pinctrl_get_group_name(struct pinctrl_dev *pctldev,
 122                unsigned group)
 123{
 124        struct spear_pmx *pmx = pinctrl_dev_get_drvdata(pctldev);
 125
 126        return pmx->machdata->groups[group]->name;
 127}
 128
 129static int spear_pinctrl_get_group_pins(struct pinctrl_dev *pctldev,
 130                unsigned group, const unsigned **pins, unsigned *num_pins)
 131{
 132        struct spear_pmx *pmx = pinctrl_dev_get_drvdata(pctldev);
 133
 134        *pins = pmx->machdata->groups[group]->pins;
 135        *num_pins = pmx->machdata->groups[group]->npins;
 136
 137        return 0;
 138}
 139
 140static void spear_pinctrl_pin_dbg_show(struct pinctrl_dev *pctldev,
 141                struct seq_file *s, unsigned offset)
 142{
 143        seq_printf(s, " " DRIVER_NAME);
 144}
 145
 146static int spear_pinctrl_dt_node_to_map(struct pinctrl_dev *pctldev,
 147                                        struct device_node *np_config,
 148                                        struct pinctrl_map **map,
 149                                        unsigned *num_maps)
 150{
 151        struct spear_pmx *pmx = pinctrl_dev_get_drvdata(pctldev);
 152        struct device_node *np;
 153        struct property *prop;
 154        const char *function, *group;
 155        int ret, index = 0, count = 0;
 156
 157        /* calculate number of maps required */
 158        for_each_child_of_node(np_config, np) {
 159                ret = of_property_read_string(np, "st,function", &function);
 160                if (ret < 0) {
 161                        of_node_put(np);
 162                        return ret;
 163                }
 164
 165                ret = of_property_count_strings(np, "st,pins");
 166                if (ret < 0) {
 167                        of_node_put(np);
 168                        return ret;
 169                }
 170
 171                count += ret;
 172        }
 173
 174        if (!count) {
 175                dev_err(pmx->dev, "No child nodes passed via DT\n");
 176                return -ENODEV;
 177        }
 178
 179        *map = kcalloc(count, sizeof(**map), GFP_KERNEL);
 180        if (!*map)
 181                return -ENOMEM;
 182
 183        for_each_child_of_node(np_config, np) {
 184                of_property_read_string(np, "st,function", &function);
 185                of_property_for_each_string(np, "st,pins", prop, group) {
 186                        (*map)[index].type = PIN_MAP_TYPE_MUX_GROUP;
 187                        (*map)[index].data.mux.group = group;
 188                        (*map)[index].data.mux.function = function;
 189                        index++;
 190                }
 191        }
 192
 193        *num_maps = count;
 194
 195        return 0;
 196}
 197
 198static void spear_pinctrl_dt_free_map(struct pinctrl_dev *pctldev,
 199                                      struct pinctrl_map *map,
 200                                      unsigned num_maps)
 201{
 202        kfree(map);
 203}
 204
 205static const struct pinctrl_ops spear_pinctrl_ops = {
 206        .get_groups_count = spear_pinctrl_get_groups_cnt,
 207        .get_group_name = spear_pinctrl_get_group_name,
 208        .get_group_pins = spear_pinctrl_get_group_pins,
 209        .pin_dbg_show = spear_pinctrl_pin_dbg_show,
 210        .dt_node_to_map = spear_pinctrl_dt_node_to_map,
 211        .dt_free_map = spear_pinctrl_dt_free_map,
 212};
 213
 214static int spear_pinctrl_get_funcs_count(struct pinctrl_dev *pctldev)
 215{
 216        struct spear_pmx *pmx = pinctrl_dev_get_drvdata(pctldev);
 217
 218        return pmx->machdata->nfunctions;
 219}
 220
 221static const char *spear_pinctrl_get_func_name(struct pinctrl_dev *pctldev,
 222                unsigned function)
 223{
 224        struct spear_pmx *pmx = pinctrl_dev_get_drvdata(pctldev);
 225
 226        return pmx->machdata->functions[function]->name;
 227}
 228
 229static int spear_pinctrl_get_func_groups(struct pinctrl_dev *pctldev,
 230                unsigned function, const char *const **groups,
 231                unsigned * const ngroups)
 232{
 233        struct spear_pmx *pmx = pinctrl_dev_get_drvdata(pctldev);
 234
 235        *groups = pmx->machdata->functions[function]->groups;
 236        *ngroups = pmx->machdata->functions[function]->ngroups;
 237
 238        return 0;
 239}
 240
 241static int spear_pinctrl_endisable(struct pinctrl_dev *pctldev,
 242                unsigned function, unsigned group, bool enable)
 243{
 244        struct spear_pmx *pmx = pinctrl_dev_get_drvdata(pctldev);
 245        const struct spear_pingroup *pgroup;
 246        const struct spear_modemux *modemux;
 247        int i;
 248        bool found = false;
 249
 250        pgroup = pmx->machdata->groups[group];
 251
 252        for (i = 0; i < pgroup->nmodemuxs; i++) {
 253                modemux = &pgroup->modemuxs[i];
 254
 255                /* SoC have any modes */
 256                if (pmx->machdata->modes_supported) {
 257                        if (!(pmx->machdata->mode & modemux->modes))
 258                                continue;
 259                }
 260
 261                found = true;
 262                muxregs_endisable(pmx, modemux->muxregs, modemux->nmuxregs,
 263                                enable);
 264        }
 265
 266        if (!found) {
 267                dev_err(pmx->dev, "pinmux group: %s not supported\n",
 268                                pgroup->name);
 269                return -ENODEV;
 270        }
 271
 272        return 0;
 273}
 274
 275static int spear_pinctrl_set_mux(struct pinctrl_dev *pctldev, unsigned function,
 276                unsigned group)
 277{
 278        return spear_pinctrl_endisable(pctldev, function, group, true);
 279}
 280
 281/* gpio with pinmux */
 282static struct spear_gpio_pingroup *get_gpio_pingroup(struct spear_pmx *pmx,
 283                unsigned pin)
 284{
 285        struct spear_gpio_pingroup *gpio_pingroup;
 286        int i, j;
 287
 288        if (!pmx->machdata->gpio_pingroups)
 289                return NULL;
 290
 291        for (i = 0; i < pmx->machdata->ngpio_pingroups; i++) {
 292                gpio_pingroup = &pmx->machdata->gpio_pingroups[i];
 293
 294                for (j = 0; j < gpio_pingroup->npins; j++) {
 295                        if (gpio_pingroup->pins[j] == pin)
 296                                return gpio_pingroup;
 297                }
 298        }
 299
 300        return NULL;
 301}
 302
 303static int gpio_request_endisable(struct pinctrl_dev *pctldev,
 304                struct pinctrl_gpio_range *range, unsigned offset, bool enable)
 305{
 306        struct spear_pmx *pmx = pinctrl_dev_get_drvdata(pctldev);
 307        struct spear_pinctrl_machdata *machdata = pmx->machdata;
 308        struct spear_gpio_pingroup *gpio_pingroup;
 309
 310        /*
 311         * Some SoC have configuration options applicable to group of pins,
 312         * rather than a single pin.
 313         */
 314        gpio_pingroup = get_gpio_pingroup(pmx, offset);
 315        if (gpio_pingroup)
 316                muxregs_endisable(pmx, gpio_pingroup->muxregs,
 317                                gpio_pingroup->nmuxregs, enable);
 318
 319        /*
 320         * SoC may need some extra configurations, or configurations for single
 321         * pin
 322         */
 323        if (machdata->gpio_request_endisable)
 324                machdata->gpio_request_endisable(pmx, offset, enable);
 325
 326        return 0;
 327}
 328
 329static int gpio_request_enable(struct pinctrl_dev *pctldev,
 330                struct pinctrl_gpio_range *range, unsigned offset)
 331{
 332        return gpio_request_endisable(pctldev, range, offset, true);
 333}
 334
 335static void gpio_disable_free(struct pinctrl_dev *pctldev,
 336                struct pinctrl_gpio_range *range, unsigned offset)
 337{
 338        gpio_request_endisable(pctldev, range, offset, false);
 339}
 340
 341static const struct pinmux_ops spear_pinmux_ops = {
 342        .get_functions_count = spear_pinctrl_get_funcs_count,
 343        .get_function_name = spear_pinctrl_get_func_name,
 344        .get_function_groups = spear_pinctrl_get_func_groups,
 345        .set_mux = spear_pinctrl_set_mux,
 346        .gpio_request_enable = gpio_request_enable,
 347        .gpio_disable_free = gpio_disable_free,
 348};
 349
 350static struct pinctrl_desc spear_pinctrl_desc = {
 351        .name = DRIVER_NAME,
 352        .pctlops = &spear_pinctrl_ops,
 353        .pmxops = &spear_pinmux_ops,
 354        .owner = THIS_MODULE,
 355};
 356
 357int spear_pinctrl_probe(struct platform_device *pdev,
 358                        struct spear_pinctrl_machdata *machdata)
 359{
 360        struct device_node *np = pdev->dev.of_node;
 361        struct spear_pmx *pmx;
 362
 363        if (!machdata)
 364                return -ENODEV;
 365
 366        pmx = devm_kzalloc(&pdev->dev, sizeof(*pmx), GFP_KERNEL);
 367        if (!pmx)
 368                return -ENOMEM;
 369
 370        pmx->vbase = devm_platform_ioremap_resource(pdev, 0);
 371        if (IS_ERR(pmx->vbase))
 372                return PTR_ERR(pmx->vbase);
 373
 374        pmx->dev = &pdev->dev;
 375        pmx->machdata = machdata;
 376
 377        /* configure mode, if supported by SoC */
 378        if (machdata->modes_supported) {
 379                int mode = 0;
 380
 381                if (of_property_read_u32(np, "st,pinmux-mode", &mode)) {
 382                        dev_err(&pdev->dev, "OF: pinmux mode not passed\n");
 383                        return -EINVAL;
 384                }
 385
 386                if (set_mode(pmx, mode)) {
 387                        dev_err(&pdev->dev, "OF: Couldn't configure mode: %x\n",
 388                                        mode);
 389                        return -EINVAL;
 390                }
 391        }
 392
 393        platform_set_drvdata(pdev, pmx);
 394
 395        spear_pinctrl_desc.pins = machdata->pins;
 396        spear_pinctrl_desc.npins = machdata->npins;
 397
 398        pmx->pctl = devm_pinctrl_register(&pdev->dev, &spear_pinctrl_desc, pmx);
 399        if (IS_ERR(pmx->pctl)) {
 400                dev_err(&pdev->dev, "Couldn't register pinctrl driver\n");
 401                return PTR_ERR(pmx->pctl);
 402        }
 403
 404        return 0;
 405}
 406