linux/drivers/pinctrl/pinctrl-single.c
<<
>>
Prefs
   1/*
   2 * Generic device tree based pinctrl driver for one register per pin
   3 * type pinmux controllers
   4 *
   5 * Copyright (C) 2012 Texas Instruments, Inc.
   6 *
   7 * This file is licensed under the terms of the GNU General Public
   8 * License version 2. This program is licensed "as is" without any
   9 * warranty of any kind, whether express or implied.
  10 */
  11
  12#include <linux/init.h>
  13#include <linux/module.h>
  14#include <linux/io.h>
  15#include <linux/slab.h>
  16#include <linux/err.h>
  17#include <linux/list.h>
  18
  19#include <linux/of.h>
  20#include <linux/of_device.h>
  21#include <linux/of_address.h>
  22
  23#include <linux/pinctrl/pinctrl.h>
  24#include <linux/pinctrl/pinmux.h>
  25
  26#include "core.h"
  27
  28#define DRIVER_NAME                     "pinctrl-single"
  29#define PCS_MUX_NAME                    "pinctrl-single,pins"
  30#define PCS_REG_NAME_LEN                ((sizeof(unsigned long) * 2) + 1)
  31#define PCS_OFF_DISABLED                ~0U
  32
  33/**
  34 * struct pcs_pingroup - pingroups for a function
  35 * @np:         pingroup device node pointer
  36 * @name:       pingroup name
  37 * @gpins:      array of the pins in the group
  38 * @ngpins:     number of pins in the group
  39 * @node:       list node
  40 */
  41struct pcs_pingroup {
  42        struct device_node *np;
  43        const char *name;
  44        int *gpins;
  45        int ngpins;
  46        struct list_head node;
  47};
  48
  49/**
  50 * struct pcs_func_vals - mux function register offset and value pair
  51 * @reg:        register virtual address
  52 * @val:        register value
  53 */
  54struct pcs_func_vals {
  55        void __iomem *reg;
  56        unsigned val;
  57};
  58
  59/**
  60 * struct pcs_function - pinctrl function
  61 * @name:       pinctrl function name
  62 * @vals:       register and vals array
  63 * @nvals:      number of entries in vals array
  64 * @pgnames:    array of pingroup names the function uses
  65 * @npgnames:   number of pingroup names the function uses
  66 * @node:       list node
  67 */
  68struct pcs_function {
  69        const char *name;
  70        struct pcs_func_vals *vals;
  71        unsigned nvals;
  72        const char **pgnames;
  73        int npgnames;
  74        struct list_head node;
  75};
  76
  77/**
  78 * struct pcs_data - wrapper for data needed by pinctrl framework
  79 * @pa:         pindesc array
  80 * @cur:        index to current element
  81 *
  82 * REVISIT: We should be able to drop this eventually by adding
  83 * support for registering pins individually in the pinctrl
  84 * framework for those drivers that don't need a static array.
  85 */
  86struct pcs_data {
  87        struct pinctrl_pin_desc *pa;
  88        int cur;
  89};
  90
  91/**
  92 * struct pcs_name - register name for a pin
  93 * @name:       name of the pinctrl register
  94 *
  95 * REVISIT: We may want to make names optional in the pinctrl
  96 * framework as some drivers may not care about pin names to
  97 * avoid kernel bloat. The pin names can be deciphered by user
  98 * space tools using debugfs based on the register address and
  99 * SoC packaging information.
 100 */
 101struct pcs_name {
 102        char name[PCS_REG_NAME_LEN];
 103};
 104
 105/**
 106 * struct pcs_device - pinctrl device instance
 107 * @res:        resources
 108 * @base:       virtual address of the controller
 109 * @size:       size of the ioremapped area
 110 * @dev:        device entry
 111 * @pctl:       pin controller device
 112 * @mutex:      mutex protecting the lists
 113 * @width:      bits per mux register
 114 * @fmask:      function register mask
 115 * @fshift:     function register shift
 116 * @foff:       value to turn mux off
 117 * @fmax:       max number of functions in fmask
 118 * @names:      array of register names for pins
 119 * @pins:       physical pins on the SoC
 120 * @pgtree:     pingroup index radix tree
 121 * @ftree:      function index radix tree
 122 * @pingroups:  list of pingroups
 123 * @functions:  list of functions
 124 * @ngroups:    number of pingroups
 125 * @nfuncs:     number of functions
 126 * @desc:       pin controller descriptor
 127 * @read:       register read function to use
 128 * @write:      register write function to use
 129 */
 130struct pcs_device {
 131        struct resource *res;
 132        void __iomem *base;
 133        unsigned size;
 134        struct device *dev;
 135        struct pinctrl_dev *pctl;
 136        struct mutex mutex;
 137        unsigned width;
 138        unsigned fmask;
 139        unsigned fshift;
 140        unsigned foff;
 141        unsigned fmax;
 142        struct pcs_name *names;
 143        struct pcs_data pins;
 144        struct radix_tree_root pgtree;
 145        struct radix_tree_root ftree;
 146        struct list_head pingroups;
 147        struct list_head functions;
 148        unsigned ngroups;
 149        unsigned nfuncs;
 150        struct pinctrl_desc desc;
 151        unsigned (*read)(void __iomem *reg);
 152        void (*write)(unsigned val, void __iomem *reg);
 153};
 154
 155/*
 156 * REVISIT: Reads and writes could eventually use regmap or something
 157 * generic. But at least on omaps, some mux registers are performance
 158 * critical as they may need to be remuxed every time before and after
 159 * idle. Adding tests for register access width for every read and
 160 * write like regmap is doing is not desired, and caching the registers
 161 * does not help in this case.
 162 */
 163
 164static unsigned __maybe_unused pcs_readb(void __iomem *reg)
 165{
 166        return readb(reg);
 167}
 168
 169static unsigned __maybe_unused pcs_readw(void __iomem *reg)
 170{
 171        return readw(reg);
 172}
 173
 174static unsigned __maybe_unused pcs_readl(void __iomem *reg)
 175{
 176        return readl(reg);
 177}
 178
 179static void __maybe_unused pcs_writeb(unsigned val, void __iomem *reg)
 180{
 181        writeb(val, reg);
 182}
 183
 184static void __maybe_unused pcs_writew(unsigned val, void __iomem *reg)
 185{
 186        writew(val, reg);
 187}
 188
 189static void __maybe_unused pcs_writel(unsigned val, void __iomem *reg)
 190{
 191        writel(val, reg);
 192}
 193
 194static int pcs_get_groups_count(struct pinctrl_dev *pctldev)
 195{
 196        struct pcs_device *pcs;
 197
 198        pcs = pinctrl_dev_get_drvdata(pctldev);
 199
 200        return pcs->ngroups;
 201}
 202
 203static const char *pcs_get_group_name(struct pinctrl_dev *pctldev,
 204                                        unsigned gselector)
 205{
 206        struct pcs_device *pcs;
 207        struct pcs_pingroup *group;
 208
 209        pcs = pinctrl_dev_get_drvdata(pctldev);
 210        group = radix_tree_lookup(&pcs->pgtree, gselector);
 211        if (!group) {
 212                dev_err(pcs->dev, "%s could not find pingroup%i\n",
 213                        __func__, gselector);
 214                return NULL;
 215        }
 216
 217        return group->name;
 218}
 219
 220static int pcs_get_group_pins(struct pinctrl_dev *pctldev,
 221                                        unsigned gselector,
 222                                        const unsigned **pins,
 223                                        unsigned *npins)
 224{
 225        struct pcs_device *pcs;
 226        struct pcs_pingroup *group;
 227
 228        pcs = pinctrl_dev_get_drvdata(pctldev);
 229        group = radix_tree_lookup(&pcs->pgtree, gselector);
 230        if (!group) {
 231                dev_err(pcs->dev, "%s could not find pingroup%i\n",
 232                        __func__, gselector);
 233                return -EINVAL;
 234        }
 235
 236        *pins = group->gpins;
 237        *npins = group->ngpins;
 238
 239        return 0;
 240}
 241
 242static void pcs_pin_dbg_show(struct pinctrl_dev *pctldev,
 243                                        struct seq_file *s,
 244                                        unsigned offset)
 245{
 246        seq_printf(s, " " DRIVER_NAME);
 247}
 248
 249static void pcs_dt_free_map(struct pinctrl_dev *pctldev,
 250                                struct pinctrl_map *map, unsigned num_maps)
 251{
 252        struct pcs_device *pcs;
 253
 254        pcs = pinctrl_dev_get_drvdata(pctldev);
 255        devm_kfree(pcs->dev, map);
 256}
 257
 258static int pcs_dt_node_to_map(struct pinctrl_dev *pctldev,
 259                                struct device_node *np_config,
 260                                struct pinctrl_map **map, unsigned *num_maps);
 261
 262static struct pinctrl_ops pcs_pinctrl_ops = {
 263        .get_groups_count = pcs_get_groups_count,
 264        .get_group_name = pcs_get_group_name,
 265        .get_group_pins = pcs_get_group_pins,
 266        .pin_dbg_show = pcs_pin_dbg_show,
 267        .dt_node_to_map = pcs_dt_node_to_map,
 268        .dt_free_map = pcs_dt_free_map,
 269};
 270
 271static int pcs_get_functions_count(struct pinctrl_dev *pctldev)
 272{
 273        struct pcs_device *pcs;
 274
 275        pcs = pinctrl_dev_get_drvdata(pctldev);
 276
 277        return pcs->nfuncs;
 278}
 279
 280static const char *pcs_get_function_name(struct pinctrl_dev *pctldev,
 281                                                unsigned fselector)
 282{
 283        struct pcs_device *pcs;
 284        struct pcs_function *func;
 285
 286        pcs = pinctrl_dev_get_drvdata(pctldev);
 287        func = radix_tree_lookup(&pcs->ftree, fselector);
 288        if (!func) {
 289                dev_err(pcs->dev, "%s could not find function%i\n",
 290                        __func__, fselector);
 291                return NULL;
 292        }
 293
 294        return func->name;
 295}
 296
 297static int pcs_get_function_groups(struct pinctrl_dev *pctldev,
 298                                        unsigned fselector,
 299                                        const char * const **groups,
 300                                        unsigned * const ngroups)
 301{
 302        struct pcs_device *pcs;
 303        struct pcs_function *func;
 304
 305        pcs = pinctrl_dev_get_drvdata(pctldev);
 306        func = radix_tree_lookup(&pcs->ftree, fselector);
 307        if (!func) {
 308                dev_err(pcs->dev, "%s could not find function%i\n",
 309                        __func__, fselector);
 310                return -EINVAL;
 311        }
 312        *groups = func->pgnames;
 313        *ngroups = func->npgnames;
 314
 315        return 0;
 316}
 317
 318static int pcs_enable(struct pinctrl_dev *pctldev, unsigned fselector,
 319        unsigned group)
 320{
 321        struct pcs_device *pcs;
 322        struct pcs_function *func;
 323        int i;
 324
 325        pcs = pinctrl_dev_get_drvdata(pctldev);
 326        func = radix_tree_lookup(&pcs->ftree, fselector);
 327        if (!func)
 328                return -EINVAL;
 329
 330        dev_dbg(pcs->dev, "enabling %s function%i\n",
 331                func->name, fselector);
 332
 333        for (i = 0; i < func->nvals; i++) {
 334                struct pcs_func_vals *vals;
 335                unsigned val;
 336
 337                vals = &func->vals[i];
 338                val = pcs->read(vals->reg);
 339                val &= ~pcs->fmask;
 340                val |= vals->val;
 341                pcs->write(val, vals->reg);
 342        }
 343
 344        return 0;
 345}
 346
 347static void pcs_disable(struct pinctrl_dev *pctldev, unsigned fselector,
 348                                        unsigned group)
 349{
 350        struct pcs_device *pcs;
 351        struct pcs_function *func;
 352        int i;
 353
 354        pcs = pinctrl_dev_get_drvdata(pctldev);
 355        func = radix_tree_lookup(&pcs->ftree, fselector);
 356        if (!func) {
 357                dev_err(pcs->dev, "%s could not find function%i\n",
 358                        __func__, fselector);
 359                return;
 360        }
 361
 362        /*
 363         * Ignore disable if function-off is not specified. Some hardware
 364         * does not have clearly defined disable function. For pin specific
 365         * off modes, you can use alternate named states as described in
 366         * pinctrl-bindings.txt.
 367         */
 368        if (pcs->foff == PCS_OFF_DISABLED) {
 369                dev_dbg(pcs->dev, "ignoring disable for %s function%i\n",
 370                        func->name, fselector);
 371                return;
 372        }
 373
 374        dev_dbg(pcs->dev, "disabling function%i %s\n",
 375                fselector, func->name);
 376
 377        for (i = 0; i < func->nvals; i++) {
 378                struct pcs_func_vals *vals;
 379                unsigned val;
 380
 381                vals = &func->vals[i];
 382                val = pcs->read(vals->reg);
 383                val &= ~pcs->fmask;
 384                val |= pcs->foff << pcs->fshift;
 385                pcs->write(val, vals->reg);
 386        }
 387}
 388
 389static int pcs_request_gpio(struct pinctrl_dev *pctldev,
 390                        struct pinctrl_gpio_range *range, unsigned offset)
 391{
 392        return -ENOTSUPP;
 393}
 394
 395static struct pinmux_ops pcs_pinmux_ops = {
 396        .get_functions_count = pcs_get_functions_count,
 397        .get_function_name = pcs_get_function_name,
 398        .get_function_groups = pcs_get_function_groups,
 399        .enable = pcs_enable,
 400        .disable = pcs_disable,
 401        .gpio_request_enable = pcs_request_gpio,
 402};
 403
 404static int pcs_pinconf_get(struct pinctrl_dev *pctldev,
 405                                unsigned pin, unsigned long *config)
 406{
 407        return -ENOTSUPP;
 408}
 409
 410static int pcs_pinconf_set(struct pinctrl_dev *pctldev,
 411                                unsigned pin, unsigned long config)
 412{
 413        return -ENOTSUPP;
 414}
 415
 416static int pcs_pinconf_group_get(struct pinctrl_dev *pctldev,
 417                                unsigned group, unsigned long *config)
 418{
 419        return -ENOTSUPP;
 420}
 421
 422static int pcs_pinconf_group_set(struct pinctrl_dev *pctldev,
 423                                unsigned group, unsigned long config)
 424{
 425        return -ENOTSUPP;
 426}
 427
 428static void pcs_pinconf_dbg_show(struct pinctrl_dev *pctldev,
 429                                struct seq_file *s, unsigned offset)
 430{
 431}
 432
 433static void pcs_pinconf_group_dbg_show(struct pinctrl_dev *pctldev,
 434                                struct seq_file *s, unsigned selector)
 435{
 436}
 437
 438static struct pinconf_ops pcs_pinconf_ops = {
 439        .pin_config_get = pcs_pinconf_get,
 440        .pin_config_set = pcs_pinconf_set,
 441        .pin_config_group_get = pcs_pinconf_group_get,
 442        .pin_config_group_set = pcs_pinconf_group_set,
 443        .pin_config_dbg_show = pcs_pinconf_dbg_show,
 444        .pin_config_group_dbg_show = pcs_pinconf_group_dbg_show,
 445};
 446
 447/**
 448 * pcs_add_pin() - add a pin to the static per controller pin array
 449 * @pcs: pcs driver instance
 450 * @offset: register offset from base
 451 */
 452static int __devinit pcs_add_pin(struct pcs_device *pcs, unsigned offset)
 453{
 454        struct pinctrl_pin_desc *pin;
 455        struct pcs_name *pn;
 456        int i;
 457
 458        i = pcs->pins.cur;
 459        if (i >= pcs->desc.npins) {
 460                dev_err(pcs->dev, "too many pins, max %i\n",
 461                        pcs->desc.npins);
 462                return -ENOMEM;
 463        }
 464
 465        pin = &pcs->pins.pa[i];
 466        pn = &pcs->names[i];
 467        sprintf(pn->name, "%lx",
 468                (unsigned long)pcs->res->start + offset);
 469        pin->name = pn->name;
 470        pin->number = i;
 471        pcs->pins.cur++;
 472
 473        return i;
 474}
 475
 476/**
 477 * pcs_allocate_pin_table() - adds all the pins for the pinctrl driver
 478 * @pcs: pcs driver instance
 479 *
 480 * In case of errors, resources are freed in pcs_free_resources.
 481 *
 482 * If your hardware needs holes in the address space, then just set
 483 * up multiple driver instances.
 484 */
 485static int __devinit pcs_allocate_pin_table(struct pcs_device *pcs)
 486{
 487        int mux_bytes, nr_pins, i;
 488
 489        mux_bytes = pcs->width / BITS_PER_BYTE;
 490        nr_pins = pcs->size / mux_bytes;
 491
 492        dev_dbg(pcs->dev, "allocating %i pins\n", nr_pins);
 493        pcs->pins.pa = devm_kzalloc(pcs->dev,
 494                                sizeof(*pcs->pins.pa) * nr_pins,
 495                                GFP_KERNEL);
 496        if (!pcs->pins.pa)
 497                return -ENOMEM;
 498
 499        pcs->names = devm_kzalloc(pcs->dev,
 500                                sizeof(struct pcs_name) * nr_pins,
 501                                GFP_KERNEL);
 502        if (!pcs->names)
 503                return -ENOMEM;
 504
 505        pcs->desc.pins = pcs->pins.pa;
 506        pcs->desc.npins = nr_pins;
 507
 508        for (i = 0; i < pcs->desc.npins; i++) {
 509                unsigned offset;
 510                int res;
 511
 512                offset = i * mux_bytes;
 513                res = pcs_add_pin(pcs, offset);
 514                if (res < 0) {
 515                        dev_err(pcs->dev, "error adding pins: %i\n", res);
 516                        return res;
 517                }
 518        }
 519
 520        return 0;
 521}
 522
 523/**
 524 * pcs_add_function() - adds a new function to the function list
 525 * @pcs: pcs driver instance
 526 * @np: device node of the mux entry
 527 * @name: name of the function
 528 * @vals: array of mux register value pairs used by the function
 529 * @nvals: number of mux register value pairs
 530 * @pgnames: array of pingroup names for the function
 531 * @npgnames: number of pingroup names
 532 */
 533static struct pcs_function *pcs_add_function(struct pcs_device *pcs,
 534                                        struct device_node *np,
 535                                        const char *name,
 536                                        struct pcs_func_vals *vals,
 537                                        unsigned nvals,
 538                                        const char **pgnames,
 539                                        unsigned npgnames)
 540{
 541        struct pcs_function *function;
 542
 543        function = devm_kzalloc(pcs->dev, sizeof(*function), GFP_KERNEL);
 544        if (!function)
 545                return NULL;
 546
 547        function->name = name;
 548        function->vals = vals;
 549        function->nvals = nvals;
 550        function->pgnames = pgnames;
 551        function->npgnames = npgnames;
 552
 553        mutex_lock(&pcs->mutex);
 554        list_add_tail(&function->node, &pcs->functions);
 555        radix_tree_insert(&pcs->ftree, pcs->nfuncs, function);
 556        pcs->nfuncs++;
 557        mutex_unlock(&pcs->mutex);
 558
 559        return function;
 560}
 561
 562static void pcs_remove_function(struct pcs_device *pcs,
 563                                struct pcs_function *function)
 564{
 565        int i;
 566
 567        mutex_lock(&pcs->mutex);
 568        for (i = 0; i < pcs->nfuncs; i++) {
 569                struct pcs_function *found;
 570
 571                found = radix_tree_lookup(&pcs->ftree, i);
 572                if (found == function)
 573                        radix_tree_delete(&pcs->ftree, i);
 574        }
 575        list_del(&function->node);
 576        mutex_unlock(&pcs->mutex);
 577}
 578
 579/**
 580 * pcs_add_pingroup() - add a pingroup to the pingroup list
 581 * @pcs: pcs driver instance
 582 * @np: device node of the mux entry
 583 * @name: name of the pingroup
 584 * @gpins: array of the pins that belong to the group
 585 * @ngpins: number of pins in the group
 586 */
 587static int pcs_add_pingroup(struct pcs_device *pcs,
 588                                        struct device_node *np,
 589                                        const char *name,
 590                                        int *gpins,
 591                                        int ngpins)
 592{
 593        struct pcs_pingroup *pingroup;
 594
 595        pingroup = devm_kzalloc(pcs->dev, sizeof(*pingroup), GFP_KERNEL);
 596        if (!pingroup)
 597                return -ENOMEM;
 598
 599        pingroup->name = name;
 600        pingroup->np = np;
 601        pingroup->gpins = gpins;
 602        pingroup->ngpins = ngpins;
 603
 604        mutex_lock(&pcs->mutex);
 605        list_add_tail(&pingroup->node, &pcs->pingroups);
 606        radix_tree_insert(&pcs->pgtree, pcs->ngroups, pingroup);
 607        pcs->ngroups++;
 608        mutex_unlock(&pcs->mutex);
 609
 610        return 0;
 611}
 612
 613/**
 614 * pcs_get_pin_by_offset() - get a pin index based on the register offset
 615 * @pcs: pcs driver instance
 616 * @offset: register offset from the base
 617 *
 618 * Note that this is OK as long as the pins are in a static array.
 619 */
 620static int pcs_get_pin_by_offset(struct pcs_device *pcs, unsigned offset)
 621{
 622        unsigned index;
 623
 624        if (offset >= pcs->size) {
 625                dev_err(pcs->dev, "mux offset out of range: 0x%x (0x%x)\n",
 626                        offset, pcs->size);
 627                return -EINVAL;
 628        }
 629
 630        index = offset / (pcs->width / BITS_PER_BYTE);
 631
 632        return index;
 633}
 634
 635/**
 636 * smux_parse_one_pinctrl_entry() - parses a device tree mux entry
 637 * @pcs: pinctrl driver instance
 638 * @np: device node of the mux entry
 639 * @map: map entry
 640 * @pgnames: pingroup names
 641 *
 642 * Note that this binding currently supports only sets of one register + value.
 643 *
 644 * Also note that this driver tries to avoid understanding pin and function
 645 * names because of the extra bloat they would cause especially in the case of
 646 * a large number of pins. This driver just sets what is specified for the board
 647 * in the .dts file. Further user space debugging tools can be developed to
 648 * decipher the pin and function names using debugfs.
 649 *
 650 * If you are concerned about the boot time, set up the static pins in
 651 * the bootloader, and only set up selected pins as device tree entries.
 652 */
 653static int pcs_parse_one_pinctrl_entry(struct pcs_device *pcs,
 654                                                struct device_node *np,
 655                                                struct pinctrl_map **map,
 656                                                const char **pgnames)
 657{
 658        struct pcs_func_vals *vals;
 659        const __be32 *mux;
 660        int size, rows, *pins, index = 0, found = 0, res = -ENOMEM;
 661        struct pcs_function *function;
 662
 663        mux = of_get_property(np, PCS_MUX_NAME, &size);
 664        if ((!mux) || (size < sizeof(*mux) * 2)) {
 665                dev_err(pcs->dev, "bad data for mux %s\n",
 666                        np->name);
 667                return -EINVAL;
 668        }
 669
 670        size /= sizeof(*mux);   /* Number of elements in array */
 671        rows = size / 2;        /* Each row is a key value pair */
 672
 673        vals = devm_kzalloc(pcs->dev, sizeof(*vals) * rows, GFP_KERNEL);
 674        if (!vals)
 675                return -ENOMEM;
 676
 677        pins = devm_kzalloc(pcs->dev, sizeof(*pins) * rows, GFP_KERNEL);
 678        if (!pins)
 679                goto free_vals;
 680
 681        while (index < size) {
 682                unsigned offset, val;
 683                int pin;
 684
 685                offset = be32_to_cpup(mux + index++);
 686                val = be32_to_cpup(mux + index++);
 687                vals[found].reg = pcs->base + offset;
 688                vals[found].val = val;
 689
 690                pin = pcs_get_pin_by_offset(pcs, offset);
 691                if (pin < 0) {
 692                        dev_err(pcs->dev,
 693                                "could not add functions for %s %ux\n",
 694                                np->name, offset);
 695                        break;
 696                }
 697                pins[found++] = pin;
 698        }
 699
 700        pgnames[0] = np->name;
 701        function = pcs_add_function(pcs, np, np->name, vals, found, pgnames, 1);
 702        if (!function)
 703                goto free_pins;
 704
 705        res = pcs_add_pingroup(pcs, np, np->name, pins, found);
 706        if (res < 0)
 707                goto free_function;
 708
 709        (*map)->type = PIN_MAP_TYPE_MUX_GROUP;
 710        (*map)->data.mux.group = np->name;
 711        (*map)->data.mux.function = np->name;
 712
 713        return 0;
 714
 715free_function:
 716        pcs_remove_function(pcs, function);
 717
 718free_pins:
 719        devm_kfree(pcs->dev, pins);
 720
 721free_vals:
 722        devm_kfree(pcs->dev, vals);
 723
 724        return res;
 725}
 726/**
 727 * pcs_dt_node_to_map() - allocates and parses pinctrl maps
 728 * @pctldev: pinctrl instance
 729 * @np_config: device tree pinmux entry
 730 * @map: array of map entries
 731 * @num_maps: number of maps
 732 */
 733static int pcs_dt_node_to_map(struct pinctrl_dev *pctldev,
 734                                struct device_node *np_config,
 735                                struct pinctrl_map **map, unsigned *num_maps)
 736{
 737        struct pcs_device *pcs;
 738        const char **pgnames;
 739        int ret;
 740
 741        pcs = pinctrl_dev_get_drvdata(pctldev);
 742
 743        *map = devm_kzalloc(pcs->dev, sizeof(**map), GFP_KERNEL);
 744        if (!map)
 745                return -ENOMEM;
 746
 747        *num_maps = 0;
 748
 749        pgnames = devm_kzalloc(pcs->dev, sizeof(*pgnames), GFP_KERNEL);
 750        if (!pgnames) {
 751                ret = -ENOMEM;
 752                goto free_map;
 753        }
 754
 755        ret = pcs_parse_one_pinctrl_entry(pcs, np_config, map, pgnames);
 756        if (ret < 0) {
 757                dev_err(pcs->dev, "no pins entries for %s\n",
 758                        np_config->name);
 759                goto free_pgnames;
 760        }
 761        *num_maps = 1;
 762
 763        return 0;
 764
 765free_pgnames:
 766        devm_kfree(pcs->dev, pgnames);
 767free_map:
 768        devm_kfree(pcs->dev, *map);
 769
 770        return ret;
 771}
 772
 773/**
 774 * pcs_free_funcs() - free memory used by functions
 775 * @pcs: pcs driver instance
 776 */
 777static void pcs_free_funcs(struct pcs_device *pcs)
 778{
 779        struct list_head *pos, *tmp;
 780        int i;
 781
 782        mutex_lock(&pcs->mutex);
 783        for (i = 0; i < pcs->nfuncs; i++) {
 784                struct pcs_function *func;
 785
 786                func = radix_tree_lookup(&pcs->ftree, i);
 787                if (!func)
 788                        continue;
 789                radix_tree_delete(&pcs->ftree, i);
 790        }
 791        list_for_each_safe(pos, tmp, &pcs->functions) {
 792                struct pcs_function *function;
 793
 794                function = list_entry(pos, struct pcs_function, node);
 795                list_del(&function->node);
 796        }
 797        mutex_unlock(&pcs->mutex);
 798}
 799
 800/**
 801 * pcs_free_pingroups() - free memory used by pingroups
 802 * @pcs: pcs driver instance
 803 */
 804static void pcs_free_pingroups(struct pcs_device *pcs)
 805{
 806        struct list_head *pos, *tmp;
 807        int i;
 808
 809        mutex_lock(&pcs->mutex);
 810        for (i = 0; i < pcs->ngroups; i++) {
 811                struct pcs_pingroup *pingroup;
 812
 813                pingroup = radix_tree_lookup(&pcs->pgtree, i);
 814                if (!pingroup)
 815                        continue;
 816                radix_tree_delete(&pcs->pgtree, i);
 817        }
 818        list_for_each_safe(pos, tmp, &pcs->pingroups) {
 819                struct pcs_pingroup *pingroup;
 820
 821                pingroup = list_entry(pos, struct pcs_pingroup, node);
 822                list_del(&pingroup->node);
 823        }
 824        mutex_unlock(&pcs->mutex);
 825}
 826
 827/**
 828 * pcs_free_resources() - free memory used by this driver
 829 * @pcs: pcs driver instance
 830 */
 831static void pcs_free_resources(struct pcs_device *pcs)
 832{
 833        if (pcs->pctl)
 834                pinctrl_unregister(pcs->pctl);
 835
 836        pcs_free_funcs(pcs);
 837        pcs_free_pingroups(pcs);
 838}
 839
 840#define PCS_GET_PROP_U32(name, reg, err)                                \
 841        do {                                                            \
 842                ret = of_property_read_u32(np, name, reg);              \
 843                if (ret) {                                              \
 844                        dev_err(pcs->dev, err);                         \
 845                        return ret;                                     \
 846                }                                                       \
 847        } while (0);
 848
 849static struct of_device_id pcs_of_match[];
 850
 851static int __devinit pcs_probe(struct platform_device *pdev)
 852{
 853        struct device_node *np = pdev->dev.of_node;
 854        const struct of_device_id *match;
 855        struct resource *res;
 856        struct pcs_device *pcs;
 857        int ret;
 858
 859        match = of_match_device(pcs_of_match, &pdev->dev);
 860        if (!match)
 861                return -EINVAL;
 862
 863        pcs = devm_kzalloc(&pdev->dev, sizeof(*pcs), GFP_KERNEL);
 864        if (!pcs) {
 865                dev_err(&pdev->dev, "could not allocate\n");
 866                return -ENOMEM;
 867        }
 868        pcs->dev = &pdev->dev;
 869        mutex_init(&pcs->mutex);
 870        INIT_LIST_HEAD(&pcs->pingroups);
 871        INIT_LIST_HEAD(&pcs->functions);
 872
 873        PCS_GET_PROP_U32("pinctrl-single,register-width", &pcs->width,
 874                         "register width not specified\n");
 875
 876        PCS_GET_PROP_U32("pinctrl-single,function-mask", &pcs->fmask,
 877                         "function register mask not specified\n");
 878        pcs->fshift = ffs(pcs->fmask) - 1;
 879        pcs->fmax = pcs->fmask >> pcs->fshift;
 880
 881        ret = of_property_read_u32(np, "pinctrl-single,function-off",
 882                                        &pcs->foff);
 883        if (ret)
 884                pcs->foff = PCS_OFF_DISABLED;
 885
 886        res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 887        if (!res) {
 888                dev_err(pcs->dev, "could not get resource\n");
 889                return -ENODEV;
 890        }
 891
 892        pcs->res = devm_request_mem_region(pcs->dev, res->start,
 893                        resource_size(res), DRIVER_NAME);
 894        if (!pcs->res) {
 895                dev_err(pcs->dev, "could not get mem_region\n");
 896                return -EBUSY;
 897        }
 898
 899        pcs->size = resource_size(pcs->res);
 900        pcs->base = devm_ioremap(pcs->dev, pcs->res->start, pcs->size);
 901        if (!pcs->base) {
 902                dev_err(pcs->dev, "could not ioremap\n");
 903                return -ENODEV;
 904        }
 905
 906        INIT_RADIX_TREE(&pcs->pgtree, GFP_KERNEL);
 907        INIT_RADIX_TREE(&pcs->ftree, GFP_KERNEL);
 908        platform_set_drvdata(pdev, pcs);
 909
 910        switch (pcs->width) {
 911        case 8:
 912                pcs->read = pcs_readb;
 913                pcs->write = pcs_writeb;
 914                break;
 915        case 16:
 916                pcs->read = pcs_readw;
 917                pcs->write = pcs_writew;
 918                break;
 919        case 32:
 920                pcs->read = pcs_readl;
 921                pcs->write = pcs_writel;
 922                break;
 923        default:
 924                break;
 925        }
 926
 927        pcs->desc.name = DRIVER_NAME;
 928        pcs->desc.pctlops = &pcs_pinctrl_ops;
 929        pcs->desc.pmxops = &pcs_pinmux_ops;
 930        pcs->desc.confops = &pcs_pinconf_ops;
 931        pcs->desc.owner = THIS_MODULE;
 932
 933        ret = pcs_allocate_pin_table(pcs);
 934        if (ret < 0)
 935                goto free;
 936
 937        pcs->pctl = pinctrl_register(&pcs->desc, pcs->dev, pcs);
 938        if (!pcs->pctl) {
 939                dev_err(pcs->dev, "could not register single pinctrl driver\n");
 940                ret = -EINVAL;
 941                goto free;
 942        }
 943
 944        dev_info(pcs->dev, "%i pins at pa %p size %u\n",
 945                 pcs->desc.npins, pcs->base, pcs->size);
 946
 947        return 0;
 948
 949free:
 950        pcs_free_resources(pcs);
 951
 952        return ret;
 953}
 954
 955static int __devexit pcs_remove(struct platform_device *pdev)
 956{
 957        struct pcs_device *pcs = platform_get_drvdata(pdev);
 958
 959        if (!pcs)
 960                return 0;
 961
 962        pcs_free_resources(pcs);
 963
 964        return 0;
 965}
 966
 967static struct of_device_id pcs_of_match[] __devinitdata = {
 968        { .compatible = DRIVER_NAME, },
 969        { },
 970};
 971MODULE_DEVICE_TABLE(of, pcs_of_match);
 972
 973static struct platform_driver pcs_driver = {
 974        .probe          = pcs_probe,
 975        .remove         = __devexit_p(pcs_remove),
 976        .driver = {
 977                .owner          = THIS_MODULE,
 978                .name           = DRIVER_NAME,
 979                .of_match_table = pcs_of_match,
 980        },
 981};
 982
 983module_platform_driver(pcs_driver);
 984
 985MODULE_AUTHOR("Tony Lindgren <tony@atomide.com>");
 986MODULE_DESCRIPTION("One-register-per-pin type device tree based pinctrl driver");
 987MODULE_LICENSE("GPL v2");
 988
lxr.linux.no kindly hosted by Redpill Linpro AS, provider of Linux consulting and operations services since 1995.