linux/arch/arm/mach-omap2/omap_device.c
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   1/*
   2 * omap_device implementation
   3 *
   4 * Copyright (C) 2009-2010 Nokia Corporation
   5 * Paul Walmsley, Kevin Hilman
   6 *
   7 * Developed in collaboration with (alphabetical order): Benoit
   8 * Cousson, Thara Gopinath, Tony Lindgren, Rajendra Nayak, Vikram
   9 * Pandita, Sakari Poussa, Anand Sawant, Santosh Shilimkar, Richard
  10 * Woodruff
  11 *
  12 * This program is free software; you can redistribute it and/or modify
  13 * it under the terms of the GNU General Public License version 2 as
  14 * published by the Free Software Foundation.
  15 *
  16 * This code provides a consistent interface for OMAP device drivers
  17 * to control power management and interconnect properties of their
  18 * devices.
  19 *
  20 * In the medium- to long-term, this code should be implemented as a
  21 * proper omap_bus/omap_device in Linux, no more platform_data func
  22 * pointers
  23 *
  24 *
  25 */
  26#undef DEBUG
  27
  28#include <linux/kernel.h>
  29#include <linux/platform_device.h>
  30#include <linux/slab.h>
  31#include <linux/err.h>
  32#include <linux/io.h>
  33#include <linux/clk.h>
  34#include <linux/clkdev.h>
  35#include <linux/pm_domain.h>
  36#include <linux/pm_runtime.h>
  37#include <linux/of.h>
  38#include <linux/of_address.h>
  39#include <linux/of_irq.h>
  40#include <linux/notifier.h>
  41
  42#include "common.h"
  43#include "soc.h"
  44#include "omap_device.h"
  45#include "omap_hwmod.h"
  46
  47/* Private functions */
  48
  49static void _add_clkdev(struct omap_device *od, const char *clk_alias,
  50                       const char *clk_name)
  51{
  52        struct clk *r;
  53        int rc;
  54
  55        if (!clk_alias || !clk_name)
  56                return;
  57
  58        dev_dbg(&od->pdev->dev, "Creating %s -> %s\n", clk_alias, clk_name);
  59
  60        r = clk_get_sys(dev_name(&od->pdev->dev), clk_alias);
  61        if (!IS_ERR(r)) {
  62                dev_dbg(&od->pdev->dev,
  63                         "alias %s already exists\n", clk_alias);
  64                clk_put(r);
  65                return;
  66        }
  67
  68        r = clk_get_sys(NULL, clk_name);
  69
  70        if (IS_ERR(r)) {
  71                struct of_phandle_args clkspec;
  72
  73                clkspec.np = of_find_node_by_name(NULL, clk_name);
  74
  75                r = of_clk_get_from_provider(&clkspec);
  76
  77                rc = clk_register_clkdev(r, clk_alias,
  78                                         dev_name(&od->pdev->dev));
  79        } else {
  80                rc = clk_add_alias(clk_alias, dev_name(&od->pdev->dev),
  81                                   clk_name, NULL);
  82        }
  83
  84        if (rc) {
  85                if (rc == -ENODEV || rc == -ENOMEM)
  86                        dev_err(&od->pdev->dev,
  87                                "clkdev_alloc for %s failed\n", clk_alias);
  88                else
  89                        dev_err(&od->pdev->dev,
  90                                "clk_get for %s failed\n", clk_name);
  91        }
  92}
  93
  94/**
  95 * _add_hwmod_clocks_clkdev - Add clkdev entry for hwmod optional clocks
  96 * and main clock
  97 * @od: struct omap_device *od
  98 * @oh: struct omap_hwmod *oh
  99 *
 100 * For the main clock and every optional clock present per hwmod per
 101 * omap_device, this function adds an entry in the clkdev table of the
 102 * form <dev-id=dev_name, con-id=role> if it does not exist already.
 103 *
 104 * The function is called from inside omap_device_build_ss(), after
 105 * omap_device_register.
 106 *
 107 * This allows drivers to get a pointer to its optional clocks based on its role
 108 * by calling clk_get(<dev*>, <role>).
 109 * In the case of the main clock, a "fck" alias is used.
 110 *
 111 * No return value.
 112 */
 113static void _add_hwmod_clocks_clkdev(struct omap_device *od,
 114                                     struct omap_hwmod *oh)
 115{
 116        int i;
 117
 118        _add_clkdev(od, "fck", oh->main_clk);
 119
 120        for (i = 0; i < oh->opt_clks_cnt; i++)
 121                _add_clkdev(od, oh->opt_clks[i].role, oh->opt_clks[i].clk);
 122}
 123
 124
 125/**
 126 * omap_device_build_from_dt - build an omap_device with multiple hwmods
 127 * @pdev_name: name of the platform_device driver to use
 128 * @pdev_id: this platform_device's connection ID
 129 * @oh: ptr to the single omap_hwmod that backs this omap_device
 130 * @pdata: platform_data ptr to associate with the platform_device
 131 * @pdata_len: amount of memory pointed to by @pdata
 132 *
 133 * Function for building an omap_device already registered from device-tree
 134 *
 135 * Returns 0 or PTR_ERR() on error.
 136 */
 137static int omap_device_build_from_dt(struct platform_device *pdev)
 138{
 139        struct omap_hwmod **hwmods;
 140        struct omap_device *od;
 141        struct omap_hwmod *oh;
 142        struct device_node *node = pdev->dev.of_node;
 143        struct resource res;
 144        const char *oh_name;
 145        int oh_cnt, i, ret = 0;
 146        bool device_active = false;
 147
 148        oh_cnt = of_property_count_strings(node, "ti,hwmods");
 149        if (oh_cnt <= 0) {
 150                dev_dbg(&pdev->dev, "No 'hwmods' to build omap_device\n");
 151                return -ENODEV;
 152        }
 153
 154        /* Use ti-sysc driver instead of omap_device? */
 155        if (!omap_hwmod_parse_module_range(NULL, node, &res))
 156                return -ENODEV;
 157
 158        hwmods = kzalloc(sizeof(struct omap_hwmod *) * oh_cnt, GFP_KERNEL);
 159        if (!hwmods) {
 160                ret = -ENOMEM;
 161                goto odbfd_exit;
 162        }
 163
 164        for (i = 0; i < oh_cnt; i++) {
 165                of_property_read_string_index(node, "ti,hwmods", i, &oh_name);
 166                oh = omap_hwmod_lookup(oh_name);
 167                if (!oh) {
 168                        dev_err(&pdev->dev, "Cannot lookup hwmod '%s'\n",
 169                                oh_name);
 170                        ret = -EINVAL;
 171                        goto odbfd_exit1;
 172                }
 173                hwmods[i] = oh;
 174                if (oh->flags & HWMOD_INIT_NO_IDLE)
 175                        device_active = true;
 176        }
 177
 178        od = omap_device_alloc(pdev, hwmods, oh_cnt);
 179        if (IS_ERR(od)) {
 180                dev_err(&pdev->dev, "Cannot allocate omap_device for :%s\n",
 181                        oh_name);
 182                ret = PTR_ERR(od);
 183                goto odbfd_exit1;
 184        }
 185
 186        /* Fix up missing resource names */
 187        for (i = 0; i < pdev->num_resources; i++) {
 188                struct resource *r = &pdev->resource[i];
 189
 190                if (r->name == NULL)
 191                        r->name = dev_name(&pdev->dev);
 192        }
 193
 194        dev_pm_domain_set(&pdev->dev, &omap_device_pm_domain);
 195
 196        if (device_active) {
 197                omap_device_enable(pdev);
 198                pm_runtime_set_active(&pdev->dev);
 199        }
 200
 201odbfd_exit1:
 202        kfree(hwmods);
 203odbfd_exit:
 204        /* if data/we are at fault.. load up a fail handler */
 205        if (ret)
 206                dev_pm_domain_set(&pdev->dev, &omap_device_fail_pm_domain);
 207
 208        return ret;
 209}
 210
 211static int _omap_device_notifier_call(struct notifier_block *nb,
 212                                      unsigned long event, void *dev)
 213{
 214        struct platform_device *pdev = to_platform_device(dev);
 215        struct omap_device *od;
 216        int err;
 217
 218        switch (event) {
 219        case BUS_NOTIFY_REMOVED_DEVICE:
 220                if (pdev->archdata.od)
 221                        omap_device_delete(pdev->archdata.od);
 222                break;
 223        case BUS_NOTIFY_UNBOUND_DRIVER:
 224                od = to_omap_device(pdev);
 225                if (od && (od->_state == OMAP_DEVICE_STATE_ENABLED)) {
 226                        dev_info(dev, "enabled after unload, idling\n");
 227                        err = omap_device_idle(pdev);
 228                        if (err)
 229                                dev_err(dev, "failed to idle\n");
 230                }
 231                break;
 232        case BUS_NOTIFY_BIND_DRIVER:
 233                od = to_omap_device(pdev);
 234                if (od && (od->_state == OMAP_DEVICE_STATE_ENABLED) &&
 235                    pm_runtime_status_suspended(dev)) {
 236                        od->_driver_status = BUS_NOTIFY_BIND_DRIVER;
 237                        pm_runtime_set_active(dev);
 238                }
 239                break;
 240        case BUS_NOTIFY_ADD_DEVICE:
 241                if (pdev->dev.of_node)
 242                        omap_device_build_from_dt(pdev);
 243                omap_auxdata_legacy_init(dev);
 244                /* fall through */
 245        default:
 246                od = to_omap_device(pdev);
 247                if (od)
 248                        od->_driver_status = event;
 249        }
 250
 251        return NOTIFY_DONE;
 252}
 253
 254/**
 255 * _omap_device_enable_hwmods - call omap_hwmod_enable() on all hwmods
 256 * @od: struct omap_device *od
 257 *
 258 * Enable all underlying hwmods.  Returns 0.
 259 */
 260static int _omap_device_enable_hwmods(struct omap_device *od)
 261{
 262        int ret = 0;
 263        int i;
 264
 265        for (i = 0; i < od->hwmods_cnt; i++)
 266                ret |= omap_hwmod_enable(od->hwmods[i]);
 267
 268        return ret;
 269}
 270
 271/**
 272 * _omap_device_idle_hwmods - call omap_hwmod_idle() on all hwmods
 273 * @od: struct omap_device *od
 274 *
 275 * Idle all underlying hwmods.  Returns 0.
 276 */
 277static int _omap_device_idle_hwmods(struct omap_device *od)
 278{
 279        int ret = 0;
 280        int i;
 281
 282        for (i = 0; i < od->hwmods_cnt; i++)
 283                ret |= omap_hwmod_idle(od->hwmods[i]);
 284
 285        return ret;
 286}
 287
 288/* Public functions for use by core code */
 289
 290/**
 291 * omap_device_get_context_loss_count - get lost context count
 292 * @od: struct omap_device *
 293 *
 294 * Using the primary hwmod, query the context loss count for this
 295 * device.
 296 *
 297 * Callers should consider context for this device lost any time this
 298 * function returns a value different than the value the caller got
 299 * the last time it called this function.
 300 *
 301 * If any hwmods exist for the omap_device associated with @pdev,
 302 * return the context loss counter for that hwmod, otherwise return
 303 * zero.
 304 */
 305int omap_device_get_context_loss_count(struct platform_device *pdev)
 306{
 307        struct omap_device *od;
 308        u32 ret = 0;
 309
 310        od = to_omap_device(pdev);
 311
 312        if (od->hwmods_cnt)
 313                ret = omap_hwmod_get_context_loss_count(od->hwmods[0]);
 314
 315        return ret;
 316}
 317
 318/**
 319 * omap_device_alloc - allocate an omap_device
 320 * @pdev: platform_device that will be included in this omap_device
 321 * @oh: ptr to the single omap_hwmod that backs this omap_device
 322 * @pdata: platform_data ptr to associate with the platform_device
 323 * @pdata_len: amount of memory pointed to by @pdata
 324 *
 325 * Convenience function for allocating an omap_device structure and filling
 326 * hwmods, and resources.
 327 *
 328 * Returns an struct omap_device pointer or ERR_PTR() on error;
 329 */
 330struct omap_device *omap_device_alloc(struct platform_device *pdev,
 331                                        struct omap_hwmod **ohs, int oh_cnt)
 332{
 333        int ret = -ENOMEM;
 334        struct omap_device *od;
 335        int i;
 336        struct omap_hwmod **hwmods;
 337
 338        od = kzalloc(sizeof(struct omap_device), GFP_KERNEL);
 339        if (!od) {
 340                ret = -ENOMEM;
 341                goto oda_exit1;
 342        }
 343        od->hwmods_cnt = oh_cnt;
 344
 345        hwmods = kmemdup(ohs, sizeof(struct omap_hwmod *) * oh_cnt, GFP_KERNEL);
 346        if (!hwmods)
 347                goto oda_exit2;
 348
 349        od->hwmods = hwmods;
 350        od->pdev = pdev;
 351        pdev->archdata.od = od;
 352
 353        for (i = 0; i < oh_cnt; i++) {
 354                hwmods[i]->od = od;
 355                _add_hwmod_clocks_clkdev(od, hwmods[i]);
 356        }
 357
 358        return od;
 359
 360oda_exit2:
 361        kfree(od);
 362oda_exit1:
 363        dev_err(&pdev->dev, "omap_device: build failed (%d)\n", ret);
 364
 365        return ERR_PTR(ret);
 366}
 367
 368void omap_device_delete(struct omap_device *od)
 369{
 370        if (!od)
 371                return;
 372
 373        od->pdev->archdata.od = NULL;
 374        kfree(od->hwmods);
 375        kfree(od);
 376}
 377
 378/**
 379 * omap_device_copy_resources - Add legacy IO and IRQ resources
 380 * @oh: interconnect target module
 381 * @pdev: platform device to copy resources to
 382 *
 383 * We still have legacy DMA and smartreflex needing resources.
 384 * Let's populate what they need until we can eventually just
 385 * remove this function. Note that there should be no need to
 386 * call this from omap_device_build_from_dt(), nor should there
 387 * be any need to call it for other devices.
 388 */
 389static int
 390omap_device_copy_resources(struct omap_hwmod *oh,
 391                           struct platform_device *pdev)
 392{
 393        struct device_node *np, *child;
 394        struct property *prop;
 395        struct resource *res;
 396        const char *name;
 397        int error, irq = 0;
 398
 399        if (!oh || !oh->od || !oh->od->pdev)
 400                return -EINVAL;
 401
 402        np = oh->od->pdev->dev.of_node;
 403        if (!np) {
 404                error = -ENODEV;
 405                goto error;
 406        }
 407
 408        res = kzalloc(sizeof(*res) * 2, GFP_KERNEL);
 409        if (!res)
 410                return -ENOMEM;
 411
 412        /* Do we have a dts range for the interconnect target module? */
 413        error = omap_hwmod_parse_module_range(oh, np, res);
 414
 415        /* No ranges, rely on device reg entry */
 416        if (error)
 417                error = of_address_to_resource(np, 0, res);
 418        if (error)
 419                goto free;
 420
 421        /* SmartReflex needs first IO resource name to be "mpu" */
 422        res[0].name = "mpu";
 423
 424        /*
 425         * We may have a configured "ti,sysc" interconnect target with a
 426         * dts child with the interrupt. If so use the first child's
 427         * first interrupt for "ti-hwmods" legacy support.
 428         */
 429        of_property_for_each_string(np, "compatible", prop, name)
 430                if (!strncmp("ti,sysc-", name, 8))
 431                        break;
 432
 433        child = of_get_next_available_child(np, NULL);
 434
 435        if (name)
 436                irq = irq_of_parse_and_map(child, 0);
 437        if (!irq)
 438                irq = irq_of_parse_and_map(np, 0);
 439        if (!irq) {
 440                error = -EINVAL;
 441                goto free;
 442        }
 443
 444        /* Legacy DMA code needs interrupt name to be "0" */
 445        res[1].start = irq;
 446        res[1].end = irq;
 447        res[1].flags = IORESOURCE_IRQ;
 448        res[1].name = "0";
 449
 450        error = platform_device_add_resources(pdev, res, 2);
 451
 452free:
 453        kfree(res);
 454
 455error:
 456        WARN(error, "%s: %s device %s failed: %i\n",
 457             __func__, oh->name, dev_name(&pdev->dev),
 458             error);
 459
 460        return error;
 461}
 462
 463/**
 464 * omap_device_build - build and register an omap_device with one omap_hwmod
 465 * @pdev_name: name of the platform_device driver to use
 466 * @pdev_id: this platform_device's connection ID
 467 * @oh: ptr to the single omap_hwmod that backs this omap_device
 468 * @pdata: platform_data ptr to associate with the platform_device
 469 * @pdata_len: amount of memory pointed to by @pdata
 470 *
 471 * Convenience function for building and registering a single
 472 * omap_device record, which in turn builds and registers a
 473 * platform_device record.  See omap_device_build_ss() for more
 474 * information.  Returns ERR_PTR(-EINVAL) if @oh is NULL; otherwise,
 475 * passes along the return value of omap_device_build_ss().
 476 */
 477struct platform_device __init *omap_device_build(const char *pdev_name,
 478                                                 int pdev_id,
 479                                                 struct omap_hwmod *oh,
 480                                                 void *pdata, int pdata_len)
 481{
 482        int ret = -ENOMEM;
 483        struct platform_device *pdev;
 484        struct omap_device *od;
 485
 486        if (!oh || !pdev_name)
 487                return ERR_PTR(-EINVAL);
 488
 489        if (!pdata && pdata_len > 0)
 490                return ERR_PTR(-EINVAL);
 491
 492        if (strncmp(oh->name, "smartreflex", 11) &&
 493            strncmp(oh->name, "dma", 3)) {
 494                pr_warn("%s need to update %s to probe with dt\na",
 495                        __func__, pdev_name);
 496                ret = -ENODEV;
 497                goto odbs_exit;
 498        }
 499
 500        pdev = platform_device_alloc(pdev_name, pdev_id);
 501        if (!pdev) {
 502                ret = -ENOMEM;
 503                goto odbs_exit;
 504        }
 505
 506        /* Set the dev_name early to allow dev_xxx in omap_device_alloc */
 507        if (pdev->id != -1)
 508                dev_set_name(&pdev->dev, "%s.%d", pdev->name,  pdev->id);
 509        else
 510                dev_set_name(&pdev->dev, "%s", pdev->name);
 511
 512        /*
 513         * Must be called before omap_device_alloc() as oh->od
 514         * only contains the currently registered omap_device
 515         * and will get overwritten by omap_device_alloc().
 516         */
 517        ret = omap_device_copy_resources(oh, pdev);
 518        if (ret)
 519                goto odbs_exit1;
 520
 521        od = omap_device_alloc(pdev, &oh, 1);
 522        if (IS_ERR(od)) {
 523                ret = PTR_ERR(od);
 524                goto odbs_exit1;
 525        }
 526
 527        ret = platform_device_add_data(pdev, pdata, pdata_len);
 528        if (ret)
 529                goto odbs_exit2;
 530
 531        ret = omap_device_register(pdev);
 532        if (ret)
 533                goto odbs_exit2;
 534
 535        return pdev;
 536
 537odbs_exit2:
 538        omap_device_delete(od);
 539odbs_exit1:
 540        platform_device_put(pdev);
 541odbs_exit:
 542
 543        pr_err("omap_device: %s: build failed (%d)\n", pdev_name, ret);
 544
 545        return ERR_PTR(ret);
 546}
 547
 548#ifdef CONFIG_PM
 549static int _od_runtime_suspend(struct device *dev)
 550{
 551        struct platform_device *pdev = to_platform_device(dev);
 552        int ret;
 553
 554        ret = pm_generic_runtime_suspend(dev);
 555        if (ret)
 556                return ret;
 557
 558        return omap_device_idle(pdev);
 559}
 560
 561static int _od_runtime_resume(struct device *dev)
 562{
 563        struct platform_device *pdev = to_platform_device(dev);
 564        int ret;
 565
 566        ret = omap_device_enable(pdev);
 567        if (ret) {
 568                dev_err(dev, "use pm_runtime_put_sync_suspend() in driver?\n");
 569                return ret;
 570        }
 571
 572        return pm_generic_runtime_resume(dev);
 573}
 574
 575static int _od_fail_runtime_suspend(struct device *dev)
 576{
 577        dev_warn(dev, "%s: FIXME: missing hwmod/omap_dev info\n", __func__);
 578        return -ENODEV;
 579}
 580
 581static int _od_fail_runtime_resume(struct device *dev)
 582{
 583        dev_warn(dev, "%s: FIXME: missing hwmod/omap_dev info\n", __func__);
 584        return -ENODEV;
 585}
 586
 587#endif
 588
 589#ifdef CONFIG_SUSPEND
 590static int _od_suspend_noirq(struct device *dev)
 591{
 592        struct platform_device *pdev = to_platform_device(dev);
 593        struct omap_device *od = to_omap_device(pdev);
 594        int ret;
 595
 596        /* Don't attempt late suspend on a driver that is not bound */
 597        if (od->_driver_status != BUS_NOTIFY_BOUND_DRIVER)
 598                return 0;
 599
 600        ret = pm_generic_suspend_noirq(dev);
 601
 602        if (!ret && !pm_runtime_status_suspended(dev)) {
 603                if (pm_generic_runtime_suspend(dev) == 0) {
 604                        omap_device_idle(pdev);
 605                        od->flags |= OMAP_DEVICE_SUSPENDED;
 606                }
 607        }
 608
 609        return ret;
 610}
 611
 612static int _od_resume_noirq(struct device *dev)
 613{
 614        struct platform_device *pdev = to_platform_device(dev);
 615        struct omap_device *od = to_omap_device(pdev);
 616
 617        if (od->flags & OMAP_DEVICE_SUSPENDED) {
 618                od->flags &= ~OMAP_DEVICE_SUSPENDED;
 619                omap_device_enable(pdev);
 620                pm_generic_runtime_resume(dev);
 621        }
 622
 623        return pm_generic_resume_noirq(dev);
 624}
 625#else
 626#define _od_suspend_noirq NULL
 627#define _od_resume_noirq NULL
 628#endif
 629
 630struct dev_pm_domain omap_device_fail_pm_domain = {
 631        .ops = {
 632                SET_RUNTIME_PM_OPS(_od_fail_runtime_suspend,
 633                                   _od_fail_runtime_resume, NULL)
 634        }
 635};
 636
 637struct dev_pm_domain omap_device_pm_domain = {
 638        .ops = {
 639                SET_RUNTIME_PM_OPS(_od_runtime_suspend, _od_runtime_resume,
 640                                   NULL)
 641                USE_PLATFORM_PM_SLEEP_OPS
 642                SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(_od_suspend_noirq,
 643                                              _od_resume_noirq)
 644        }
 645};
 646
 647/**
 648 * omap_device_register - register an omap_device with one omap_hwmod
 649 * @od: struct omap_device * to register
 650 *
 651 * Register the omap_device structure.  This currently just calls
 652 * platform_device_register() on the underlying platform_device.
 653 * Returns the return value of platform_device_register().
 654 */
 655int omap_device_register(struct platform_device *pdev)
 656{
 657        pr_debug("omap_device: %s: registering\n", pdev->name);
 658
 659        dev_pm_domain_set(&pdev->dev, &omap_device_pm_domain);
 660        return platform_device_add(pdev);
 661}
 662
 663
 664/* Public functions for use by device drivers through struct platform_data */
 665
 666/**
 667 * omap_device_enable - fully activate an omap_device
 668 * @od: struct omap_device * to activate
 669 *
 670 * Do whatever is necessary for the hwmods underlying omap_device @od
 671 * to be accessible and ready to operate.  This generally involves
 672 * enabling clocks, setting SYSCONFIG registers; and in the future may
 673 * involve remuxing pins.  Device drivers should call this function
 674 * indirectly via pm_runtime_get*().  Returns -EINVAL if called when
 675 * the omap_device is already enabled, or passes along the return
 676 * value of _omap_device_enable_hwmods().
 677 */
 678int omap_device_enable(struct platform_device *pdev)
 679{
 680        int ret;
 681        struct omap_device *od;
 682
 683        od = to_omap_device(pdev);
 684
 685        if (od->_state == OMAP_DEVICE_STATE_ENABLED) {
 686                dev_warn(&pdev->dev,
 687                         "omap_device: %s() called from invalid state %d\n",
 688                         __func__, od->_state);
 689                return -EINVAL;
 690        }
 691
 692        ret = _omap_device_enable_hwmods(od);
 693
 694        if (ret == 0)
 695                od->_state = OMAP_DEVICE_STATE_ENABLED;
 696
 697        return ret;
 698}
 699
 700/**
 701 * omap_device_idle - idle an omap_device
 702 * @od: struct omap_device * to idle
 703 *
 704 * Idle omap_device @od.  Device drivers call this function indirectly
 705 * via pm_runtime_put*().  Returns -EINVAL if the omap_device is not
 706 * currently enabled, or passes along the return value of
 707 * _omap_device_idle_hwmods().
 708 */
 709int omap_device_idle(struct platform_device *pdev)
 710{
 711        int ret;
 712        struct omap_device *od;
 713
 714        od = to_omap_device(pdev);
 715
 716        if (od->_state != OMAP_DEVICE_STATE_ENABLED) {
 717                dev_warn(&pdev->dev,
 718                         "omap_device: %s() called from invalid state %d\n",
 719                         __func__, od->_state);
 720                return -EINVAL;
 721        }
 722
 723        ret = _omap_device_idle_hwmods(od);
 724
 725        if (ret == 0)
 726                od->_state = OMAP_DEVICE_STATE_IDLE;
 727
 728        return ret;
 729}
 730
 731/**
 732 * omap_device_assert_hardreset - set a device's hardreset line
 733 * @pdev: struct platform_device * to reset
 734 * @name: const char * name of the reset line
 735 *
 736 * Set the hardreset line identified by @name on the IP blocks
 737 * associated with the hwmods backing the platform_device @pdev.  All
 738 * of the hwmods associated with @pdev must have the same hardreset
 739 * line linked to them for this to work.  Passes along the return value
 740 * of omap_hwmod_assert_hardreset() in the event of any failure, or
 741 * returns 0 upon success.
 742 */
 743int omap_device_assert_hardreset(struct platform_device *pdev, const char *name)
 744{
 745        struct omap_device *od = to_omap_device(pdev);
 746        int ret = 0;
 747        int i;
 748
 749        for (i = 0; i < od->hwmods_cnt; i++) {
 750                ret = omap_hwmod_assert_hardreset(od->hwmods[i], name);
 751                if (ret)
 752                        break;
 753        }
 754
 755        return ret;
 756}
 757
 758/**
 759 * omap_device_deassert_hardreset - release a device's hardreset line
 760 * @pdev: struct platform_device * to reset
 761 * @name: const char * name of the reset line
 762 *
 763 * Release the hardreset line identified by @name on the IP blocks
 764 * associated with the hwmods backing the platform_device @pdev.  All
 765 * of the hwmods associated with @pdev must have the same hardreset
 766 * line linked to them for this to work.  Passes along the return
 767 * value of omap_hwmod_deassert_hardreset() in the event of any
 768 * failure, or returns 0 upon success.
 769 */
 770int omap_device_deassert_hardreset(struct platform_device *pdev,
 771                                   const char *name)
 772{
 773        struct omap_device *od = to_omap_device(pdev);
 774        int ret = 0;
 775        int i;
 776
 777        for (i = 0; i < od->hwmods_cnt; i++) {
 778                ret = omap_hwmod_deassert_hardreset(od->hwmods[i], name);
 779                if (ret)
 780                        break;
 781        }
 782
 783        return ret;
 784}
 785
 786/**
 787 * omap_device_get_by_hwmod_name() - convert a hwmod name to
 788 * device pointer.
 789 * @oh_name: name of the hwmod device
 790 *
 791 * Returns back a struct device * pointer associated with a hwmod
 792 * device represented by a hwmod_name
 793 */
 794struct device *omap_device_get_by_hwmod_name(const char *oh_name)
 795{
 796        struct omap_hwmod *oh;
 797
 798        if (!oh_name) {
 799                WARN(1, "%s: no hwmod name!\n", __func__);
 800                return ERR_PTR(-EINVAL);
 801        }
 802
 803        oh = omap_hwmod_lookup(oh_name);
 804        if (!oh) {
 805                WARN(1, "%s: no hwmod for %s\n", __func__,
 806                        oh_name);
 807                return ERR_PTR(-ENODEV);
 808        }
 809        if (!oh->od) {
 810                WARN(1, "%s: no omap_device for %s\n", __func__,
 811                        oh_name);
 812                return ERR_PTR(-ENODEV);
 813        }
 814
 815        return &oh->od->pdev->dev;
 816}
 817
 818static struct notifier_block platform_nb = {
 819        .notifier_call = _omap_device_notifier_call,
 820};
 821
 822static int __init omap_device_init(void)
 823{
 824        bus_register_notifier(&platform_bus_type, &platform_nb);
 825        return 0;
 826}
 827omap_postcore_initcall(omap_device_init);
 828
 829/**
 830 * omap_device_late_idle - idle devices without drivers
 831 * @dev: struct device * associated with omap_device
 832 * @data: unused
 833 *
 834 * Check the driver bound status of this device, and idle it
 835 * if there is no driver attached.
 836 */
 837static int __init omap_device_late_idle(struct device *dev, void *data)
 838{
 839        struct platform_device *pdev = to_platform_device(dev);
 840        struct omap_device *od = to_omap_device(pdev);
 841        int i;
 842
 843        if (!od)
 844                return 0;
 845
 846        /*
 847         * If omap_device state is enabled, but has no driver bound,
 848         * idle it.
 849         */
 850
 851        /*
 852         * Some devices (like memory controllers) are always kept
 853         * enabled, and should not be idled even with no drivers.
 854         */
 855        for (i = 0; i < od->hwmods_cnt; i++)
 856                if (od->hwmods[i]->flags & HWMOD_INIT_NO_IDLE)
 857                        return 0;
 858
 859        if (od->_driver_status != BUS_NOTIFY_BOUND_DRIVER &&
 860            od->_driver_status != BUS_NOTIFY_BIND_DRIVER) {
 861                if (od->_state == OMAP_DEVICE_STATE_ENABLED) {
 862                        dev_warn(dev, "%s: enabled but no driver.  Idling\n",
 863                                 __func__);
 864                        omap_device_idle(pdev);
 865                }
 866        }
 867
 868        return 0;
 869}
 870
 871static int __init omap_device_late_init(void)
 872{
 873        bus_for_each_dev(&platform_bus_type, NULL, NULL, omap_device_late_idle);
 874
 875        return 0;
 876}
 877omap_late_initcall_sync(omap_device_late_init);
 878