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                        return ret;
 162
 163                ret = of_property_count_strings(np, "st,pins");
 164                if (ret < 0)
 165                        return ret;
 166
 167                count += ret;
 168        }
 169
 170        if (!count) {
 171                dev_err(pmx->dev, "No child nodes passed via DT\n");
 172                return -ENODEV;
 173        }
 174
 175        *map = kcalloc(count, sizeof(**map), GFP_KERNEL);
 176        if (!*map)
 177                return -ENOMEM;
 178
 179        for_each_child_of_node(np_config, np) {
 180                of_property_read_string(np, "st,function", &function);
 181                of_property_for_each_string(np, "st,pins", prop, group) {
 182                        (*map)[index].type = PIN_MAP_TYPE_MUX_GROUP;
 183                        (*map)[index].data.mux.group = group;
 184                        (*map)[index].data.mux.function = function;
 185                        index++;
 186                }
 187        }
 188
 189        *num_maps = count;
 190
 191        return 0;
 192}
 193
 194static void spear_pinctrl_dt_free_map(struct pinctrl_dev *pctldev,
 195                                      struct pinctrl_map *map,
 196                                      unsigned num_maps)
 197{
 198        kfree(map);
 199}
 200
 201static const struct pinctrl_ops spear_pinctrl_ops = {
 202        .get_groups_count = spear_pinctrl_get_groups_cnt,
 203        .get_group_name = spear_pinctrl_get_group_name,
 204        .get_group_pins = spear_pinctrl_get_group_pins,
 205        .pin_dbg_show = spear_pinctrl_pin_dbg_show,
 206        .dt_node_to_map = spear_pinctrl_dt_node_to_map,
 207        .dt_free_map = spear_pinctrl_dt_free_map,
 208};
 209
 210static int spear_pinctrl_get_funcs_count(struct pinctrl_dev *pctldev)
 211{
 212        struct spear_pmx *pmx = pinctrl_dev_get_drvdata(pctldev);
 213
 214        return pmx->machdata->nfunctions;
 215}
 216
 217static const char *spear_pinctrl_get_func_name(struct pinctrl_dev *pctldev,
 218                unsigned function)
 219{
 220        struct spear_pmx *pmx = pinctrl_dev_get_drvdata(pctldev);
 221
 222        return pmx->machdata->functions[function]->name;
 223}
 224
 225static int spear_pinctrl_get_func_groups(struct pinctrl_dev *pctldev,
 226                unsigned function, const char *const **groups,
 227                unsigned * const ngroups)
 228{
 229        struct spear_pmx *pmx = pinctrl_dev_get_drvdata(pctldev);
 230
 231        *groups = pmx->machdata->functions[function]->groups;
 232        *ngroups = pmx->machdata->functions[function]->ngroups;
 233
 234        return 0;
 235}
 236
 237static int spear_pinctrl_endisable(struct pinctrl_dev *pctldev,
 238                unsigned function, unsigned group, bool enable)
 239{
 240        struct spear_pmx *pmx = pinctrl_dev_get_drvdata(pctldev);
 241        const struct spear_pingroup *pgroup;
 242        const struct spear_modemux *modemux;
 243        int i;
 244        bool found = false;
 245
 246        pgroup = pmx->machdata->groups[group];
 247
 248        for (i = 0; i < pgroup->nmodemuxs; i++) {
 249                modemux = &pgroup->modemuxs[i];
 250
 251                /* SoC have any modes */
 252                if (pmx->machdata->modes_supported) {
 253                        if (!(pmx->machdata->mode & modemux->modes))
 254                                continue;
 255                }
 256
 257                found = true;
 258                muxregs_endisable(pmx, modemux->muxregs, modemux->nmuxregs,
 259                                enable);
 260        }
 261
 262        if (!found) {
 263                dev_err(pmx->dev, "pinmux group: %s not supported\n",
 264                                pgroup->name);
 265                return -ENODEV;
 266        }
 267
 268        return 0;
 269}
 270
 271static int spear_pinctrl_set_mux(struct pinctrl_dev *pctldev, unsigned function,
 272                unsigned group)
 273{
 274        return spear_pinctrl_endisable(pctldev, function, group, true);
 275}
 276
 277/* gpio with pinmux */
 278static struct spear_gpio_pingroup *get_gpio_pingroup(struct spear_pmx *pmx,
 279                unsigned pin)
 280{
 281        struct spear_gpio_pingroup *gpio_pingroup;
 282        int i, j;
 283
 284        if (!pmx->machdata->gpio_pingroups)
 285                return NULL;
 286
 287        for (i = 0; i < pmx->machdata->ngpio_pingroups; i++) {
 288                gpio_pingroup = &pmx->machdata->gpio_pingroups[i];
 289
 290                for (j = 0; j < gpio_pingroup->npins; j++) {
 291                        if (gpio_pingroup->pins[j] == pin)
 292                                return gpio_pingroup;
 293                }
 294        }
 295
 296        return NULL;
 297}
 298
 299static int gpio_request_endisable(struct pinctrl_dev *pctldev,
 300                struct pinctrl_gpio_range *range, unsigned offset, bool enable)
 301{
 302        struct spear_pmx *pmx = pinctrl_dev_get_drvdata(pctldev);
 303        struct spear_pinctrl_machdata *machdata = pmx->machdata;
 304        struct spear_gpio_pingroup *gpio_pingroup;
 305
 306        /*
 307         * Some SoC have configuration options applicable to group of pins,
 308         * rather than a single pin.
 309         */
 310        gpio_pingroup = get_gpio_pingroup(pmx, offset);
 311        if (gpio_pingroup)
 312                muxregs_endisable(pmx, gpio_pingroup->muxregs,
 313                                gpio_pingroup->nmuxregs, enable);
 314
 315        /*
 316         * SoC may need some extra configurations, or configurations for single
 317         * pin
 318         */
 319        if (machdata->gpio_request_endisable)
 320                machdata->gpio_request_endisable(pmx, offset, enable);
 321
 322        return 0;
 323}
 324
 325static int gpio_request_enable(struct pinctrl_dev *pctldev,
 326                struct pinctrl_gpio_range *range, unsigned offset)
 327{
 328        return gpio_request_endisable(pctldev, range, offset, true);
 329}
 330
 331static void gpio_disable_free(struct pinctrl_dev *pctldev,
 332                struct pinctrl_gpio_range *range, unsigned offset)
 333{
 334        gpio_request_endisable(pctldev, range, offset, false);
 335}
 336
 337static const struct pinmux_ops spear_pinmux_ops = {
 338        .get_functions_count = spear_pinctrl_get_funcs_count,
 339        .get_function_name = spear_pinctrl_get_func_name,
 340        .get_function_groups = spear_pinctrl_get_func_groups,
 341        .set_mux = spear_pinctrl_set_mux,
 342        .gpio_request_enable = gpio_request_enable,
 343        .gpio_disable_free = gpio_disable_free,
 344};
 345
 346static struct pinctrl_desc spear_pinctrl_desc = {
 347        .name = DRIVER_NAME,
 348        .pctlops = &spear_pinctrl_ops,
 349        .pmxops = &spear_pinmux_ops,
 350        .owner = THIS_MODULE,
 351};
 352
 353int spear_pinctrl_probe(struct platform_device *pdev,
 354                        struct spear_pinctrl_machdata *machdata)
 355{
 356        struct device_node *np = pdev->dev.of_node;
 357        struct resource *res;
 358        struct spear_pmx *pmx;
 359
 360        if (!machdata)
 361                return -ENODEV;
 362
 363        pmx = devm_kzalloc(&pdev->dev, sizeof(*pmx), GFP_KERNEL);
 364        if (!pmx)
 365                return -ENOMEM;
 366
 367        res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 368        pmx->vbase = devm_ioremap_resource(&pdev->dev, res);
 369        if (IS_ERR(pmx->vbase))
 370                return PTR_ERR(pmx->vbase);
 371
 372        pmx->dev = &pdev->dev;
 373        pmx->machdata = machdata;
 374
 375        /* configure mode, if supported by SoC */
 376        if (machdata->modes_supported) {
 377                int mode = 0;
 378
 379                if (of_property_read_u32(np, "st,pinmux-mode", &mode)) {
 380                        dev_err(&pdev->dev, "OF: pinmux mode not passed\n");
 381                        return -EINVAL;
 382                }
 383
 384                if (set_mode(pmx, mode)) {
 385                        dev_err(&pdev->dev, "OF: Couldn't configure mode: %x\n",
 386                                        mode);
 387                        return -EINVAL;
 388                }
 389        }
 390
 391        platform_set_drvdata(pdev, pmx);
 392
 393        spear_pinctrl_desc.pins = machdata->pins;
 394        spear_pinctrl_desc.npins = machdata->npins;
 395
 396        pmx->pctl = devm_pinctrl_register(&pdev->dev, &spear_pinctrl_desc, pmx);
 397        if (IS_ERR(pmx->pctl)) {
 398                dev_err(&pdev->dev, "Couldn't register pinctrl driver\n");
 399                return PTR_ERR(pmx->pctl);
 400        }
 401
 402        return 0;
 403}
 404