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0001 // SPDX-License-Identifier: GPL-2.0-only
0002 /*
0003  * omap_device implementation
0004  *
0005  * Copyright (C) 2009-2010 Nokia Corporation
0006  * Paul Walmsley, Kevin Hilman
0007  *
0008  * Developed in collaboration with (alphabetical order): Benoit
0009  * Cousson, Thara Gopinath, Tony Lindgren, Rajendra Nayak, Vikram
0010  * Pandita, Sakari Poussa, Anand Sawant, Santosh Shilimkar, Richard
0011  * Woodruff
0012  *
0013  * This code provides a consistent interface for OMAP device drivers
0014  * to control power management and interconnect properties of their
0015  * devices.
0016  *
0017  * In the medium- to long-term, this code should be implemented as a
0018  * proper omap_bus/omap_device in Linux, no more platform_data func
0019  * pointers
0020  */
0021 #undef DEBUG
0022 
0023 #include <linux/kernel.h>
0024 #include <linux/platform_device.h>
0025 #include <linux/slab.h>
0026 #include <linux/err.h>
0027 #include <linux/io.h>
0028 #include <linux/clk.h>
0029 #include <linux/clkdev.h>
0030 #include <linux/pm_domain.h>
0031 #include <linux/pm_runtime.h>
0032 #include <linux/of.h>
0033 #include <linux/of_address.h>
0034 #include <linux/of_irq.h>
0035 #include <linux/notifier.h>
0036 
0037 #include "common.h"
0038 #include "soc.h"
0039 #include "omap_device.h"
0040 #include "omap_hwmod.h"
0041 
0042 /* Private functions */
0043 
0044 static void _add_clkdev(struct omap_device *od, const char *clk_alias,
0045                const char *clk_name)
0046 {
0047     struct clk *r;
0048     int rc;
0049 
0050     if (!clk_alias || !clk_name)
0051         return;
0052 
0053     dev_dbg(&od->pdev->dev, "Creating %s -> %s\n", clk_alias, clk_name);
0054 
0055     r = clk_get_sys(dev_name(&od->pdev->dev), clk_alias);
0056     if (!IS_ERR(r)) {
0057         dev_dbg(&od->pdev->dev,
0058              "alias %s already exists\n", clk_alias);
0059         clk_put(r);
0060         return;
0061     }
0062 
0063     r = clk_get_sys(NULL, clk_name);
0064 
0065     if (IS_ERR(r)) {
0066         struct of_phandle_args clkspec;
0067 
0068         clkspec.np = of_find_node_by_name(NULL, clk_name);
0069 
0070         r = of_clk_get_from_provider(&clkspec);
0071 
0072         rc = clk_register_clkdev(r, clk_alias,
0073                      dev_name(&od->pdev->dev));
0074     } else {
0075         rc = clk_add_alias(clk_alias, dev_name(&od->pdev->dev),
0076                    clk_name, NULL);
0077     }
0078 
0079     if (rc) {
0080         if (rc == -ENODEV || rc == -ENOMEM)
0081             dev_err(&od->pdev->dev,
0082                 "clkdev_alloc for %s failed\n", clk_alias);
0083         else
0084             dev_err(&od->pdev->dev,
0085                 "clk_get for %s failed\n", clk_name);
0086     }
0087 }
0088 
0089 /**
0090  * _add_hwmod_clocks_clkdev - Add clkdev entry for hwmod optional clocks
0091  * and main clock
0092  * @od: struct omap_device *od
0093  * @oh: struct omap_hwmod *oh
0094  *
0095  * For the main clock and every optional clock present per hwmod per
0096  * omap_device, this function adds an entry in the clkdev table of the
0097  * form <dev-id=dev_name, con-id=role> if it does not exist already.
0098  *
0099  * This allows drivers to get a pointer to its optional clocks based on its role
0100  * by calling clk_get(<dev*>, <role>).
0101  * In the case of the main clock, a "fck" alias is used.
0102  *
0103  * No return value.
0104  */
0105 static void _add_hwmod_clocks_clkdev(struct omap_device *od,
0106                      struct omap_hwmod *oh)
0107 {
0108     int i;
0109 
0110     _add_clkdev(od, "fck", oh->main_clk);
0111 
0112     for (i = 0; i < oh->opt_clks_cnt; i++)
0113         _add_clkdev(od, oh->opt_clks[i].role, oh->opt_clks[i].clk);
0114 }
0115 
0116 
0117 /**
0118  * omap_device_build_from_dt - build an omap_device with multiple hwmods
0119  * @pdev: The platform device to update.
0120  *
0121  * Function for building an omap_device already registered from device-tree
0122  *
0123  * Returns 0 or PTR_ERR() on error.
0124  */
0125 static int omap_device_build_from_dt(struct platform_device *pdev)
0126 {
0127     struct omap_hwmod **hwmods;
0128     struct omap_device *od;
0129     struct omap_hwmod *oh;
0130     struct device_node *node = pdev->dev.of_node;
0131     struct resource res;
0132     const char *oh_name;
0133     int oh_cnt, i, ret = 0;
0134     bool device_active = false, skip_pm_domain = false;
0135 
0136     oh_cnt = of_property_count_strings(node, "ti,hwmods");
0137     if (oh_cnt <= 0) {
0138         dev_dbg(&pdev->dev, "No 'hwmods' to build omap_device\n");
0139         return -ENODEV;
0140     }
0141 
0142     /* SDMA still needs special handling for omap_device_build() */
0143     ret = of_property_read_string_index(node, "ti,hwmods", 0, &oh_name);
0144     if (!ret && (!strncmp("dma_system", oh_name, 10) ||
0145              !strncmp("dma", oh_name, 3)))
0146         skip_pm_domain = true;
0147 
0148     /* Use ti-sysc driver instead of omap_device? */
0149     if (!skip_pm_domain &&
0150         !omap_hwmod_parse_module_range(NULL, node, &res))
0151         return -ENODEV;
0152 
0153     hwmods = kcalloc(oh_cnt, sizeof(struct omap_hwmod *), GFP_KERNEL);
0154     if (!hwmods) {
0155         ret = -ENOMEM;
0156         goto odbfd_exit;
0157     }
0158 
0159     for (i = 0; i < oh_cnt; i++) {
0160         of_property_read_string_index(node, "ti,hwmods", i, &oh_name);
0161         oh = omap_hwmod_lookup(oh_name);
0162         if (!oh) {
0163             dev_err(&pdev->dev, "Cannot lookup hwmod '%s'\n",
0164                 oh_name);
0165             ret = -EINVAL;
0166             goto odbfd_exit1;
0167         }
0168         hwmods[i] = oh;
0169         if (oh->flags & HWMOD_INIT_NO_IDLE)
0170             device_active = true;
0171     }
0172 
0173     od = omap_device_alloc(pdev, hwmods, oh_cnt);
0174     if (IS_ERR(od)) {
0175         dev_err(&pdev->dev, "Cannot allocate omap_device for :%s\n",
0176             oh_name);
0177         ret = PTR_ERR(od);
0178         goto odbfd_exit1;
0179     }
0180 
0181     /* Fix up missing resource names */
0182     for (i = 0; i < pdev->num_resources; i++) {
0183         struct resource *r = &pdev->resource[i];
0184 
0185         if (r->name == NULL)
0186             r->name = dev_name(&pdev->dev);
0187     }
0188 
0189     if (!skip_pm_domain) {
0190         dev_pm_domain_set(&pdev->dev, &omap_device_pm_domain);
0191         if (device_active) {
0192             omap_device_enable(pdev);
0193             pm_runtime_set_active(&pdev->dev);
0194         }
0195     }
0196 
0197 odbfd_exit1:
0198     kfree(hwmods);
0199 odbfd_exit:
0200     /* if data/we are at fault.. load up a fail handler */
0201     if (ret)
0202         dev_pm_domain_set(&pdev->dev, &omap_device_fail_pm_domain);
0203 
0204     return ret;
0205 }
0206 
0207 static int _omap_device_notifier_call(struct notifier_block *nb,
0208                       unsigned long event, void *dev)
0209 {
0210     struct platform_device *pdev = to_platform_device(dev);
0211     struct omap_device *od;
0212     int err;
0213 
0214     switch (event) {
0215     case BUS_NOTIFY_REMOVED_DEVICE:
0216         if (pdev->archdata.od)
0217             omap_device_delete(pdev->archdata.od);
0218         break;
0219     case BUS_NOTIFY_UNBOUND_DRIVER:
0220         od = to_omap_device(pdev);
0221         if (od && (od->_state == OMAP_DEVICE_STATE_ENABLED)) {
0222             dev_info(dev, "enabled after unload, idling\n");
0223             err = omap_device_idle(pdev);
0224             if (err)
0225                 dev_err(dev, "failed to idle\n");
0226         }
0227         break;
0228     case BUS_NOTIFY_BIND_DRIVER:
0229         od = to_omap_device(pdev);
0230         if (od) {
0231             od->_driver_status = BUS_NOTIFY_BIND_DRIVER;
0232             if (od->_state == OMAP_DEVICE_STATE_ENABLED &&
0233                 pm_runtime_status_suspended(dev)) {
0234                 pm_runtime_set_active(dev);
0235             }
0236         }
0237         break;
0238     case BUS_NOTIFY_ADD_DEVICE:
0239         if (pdev->dev.of_node)
0240             omap_device_build_from_dt(pdev);
0241         omap_auxdata_legacy_init(dev);
0242         fallthrough;
0243     default:
0244         od = to_omap_device(pdev);
0245         if (od)
0246             od->_driver_status = event;
0247     }
0248 
0249     return NOTIFY_DONE;
0250 }
0251 
0252 /**
0253  * _omap_device_enable_hwmods - call omap_hwmod_enable() on all hwmods
0254  * @od: struct omap_device *od
0255  *
0256  * Enable all underlying hwmods.  Returns 0.
0257  */
0258 static int _omap_device_enable_hwmods(struct omap_device *od)
0259 {
0260     int ret = 0;
0261     int i;
0262 
0263     for (i = 0; i < od->hwmods_cnt; i++)
0264         ret |= omap_hwmod_enable(od->hwmods[i]);
0265 
0266     return ret;
0267 }
0268 
0269 /**
0270  * _omap_device_idle_hwmods - call omap_hwmod_idle() on all hwmods
0271  * @od: struct omap_device *od
0272  *
0273  * Idle all underlying hwmods.  Returns 0.
0274  */
0275 static int _omap_device_idle_hwmods(struct omap_device *od)
0276 {
0277     int ret = 0;
0278     int i;
0279 
0280     for (i = 0; i < od->hwmods_cnt; i++)
0281         ret |= omap_hwmod_idle(od->hwmods[i]);
0282 
0283     return ret;
0284 }
0285 
0286 /* Public functions for use by core code */
0287 
0288 /**
0289  * omap_device_get_context_loss_count - get lost context count
0290  * @pdev: The platform device to update.
0291  *
0292  * Using the primary hwmod, query the context loss count for this
0293  * device.
0294  *
0295  * Callers should consider context for this device lost any time this
0296  * function returns a value different than the value the caller got
0297  * the last time it called this function.
0298  *
0299  * If any hwmods exist for the omap_device associated with @pdev,
0300  * return the context loss counter for that hwmod, otherwise return
0301  * zero.
0302  */
0303 int omap_device_get_context_loss_count(struct platform_device *pdev)
0304 {
0305     struct omap_device *od;
0306     u32 ret = 0;
0307 
0308     od = to_omap_device(pdev);
0309 
0310     if (od->hwmods_cnt)
0311         ret = omap_hwmod_get_context_loss_count(od->hwmods[0]);
0312 
0313     return ret;
0314 }
0315 
0316 /**
0317  * omap_device_alloc - allocate an omap_device
0318  * @pdev: platform_device that will be included in this omap_device
0319  * @ohs: ptr to the omap_hwmod for this omap_device
0320  * @oh_cnt: the size of the ohs list
0321  *
0322  * Convenience function for allocating an omap_device structure and filling
0323  * hwmods, and resources.
0324  *
0325  * Returns an struct omap_device pointer or ERR_PTR() on error;
0326  */
0327 struct omap_device *omap_device_alloc(struct platform_device *pdev,
0328                     struct omap_hwmod **ohs, int oh_cnt)
0329 {
0330     int ret = -ENOMEM;
0331     struct omap_device *od;
0332     int i;
0333     struct omap_hwmod **hwmods;
0334 
0335     od = kzalloc(sizeof(struct omap_device), GFP_KERNEL);
0336     if (!od)
0337         goto oda_exit1;
0338 
0339     od->hwmods_cnt = oh_cnt;
0340 
0341     hwmods = kmemdup(ohs, sizeof(struct omap_hwmod *) * oh_cnt, GFP_KERNEL);
0342     if (!hwmods)
0343         goto oda_exit2;
0344 
0345     od->hwmods = hwmods;
0346     od->pdev = pdev;
0347     pdev->archdata.od = od;
0348 
0349     for (i = 0; i < oh_cnt; i++) {
0350         hwmods[i]->od = od;
0351         _add_hwmod_clocks_clkdev(od, hwmods[i]);
0352     }
0353 
0354     return od;
0355 
0356 oda_exit2:
0357     kfree(od);
0358 oda_exit1:
0359     dev_err(&pdev->dev, "omap_device: build failed (%d)\n", ret);
0360 
0361     return ERR_PTR(ret);
0362 }
0363 
0364 void omap_device_delete(struct omap_device *od)
0365 {
0366     if (!od)
0367         return;
0368 
0369     od->pdev->archdata.od = NULL;
0370     kfree(od->hwmods);
0371     kfree(od);
0372 }
0373 
0374 #ifdef CONFIG_PM
0375 static int _od_runtime_suspend(struct device *dev)
0376 {
0377     struct platform_device *pdev = to_platform_device(dev);
0378     int ret;
0379 
0380     ret = pm_generic_runtime_suspend(dev);
0381     if (ret)
0382         return ret;
0383 
0384     return omap_device_idle(pdev);
0385 }
0386 
0387 static int _od_runtime_resume(struct device *dev)
0388 {
0389     struct platform_device *pdev = to_platform_device(dev);
0390     int ret;
0391 
0392     ret = omap_device_enable(pdev);
0393     if (ret) {
0394         dev_err(dev, "use pm_runtime_put_sync_suspend() in driver?\n");
0395         return ret;
0396     }
0397 
0398     return pm_generic_runtime_resume(dev);
0399 }
0400 
0401 static int _od_fail_runtime_suspend(struct device *dev)
0402 {
0403     dev_warn(dev, "%s: FIXME: missing hwmod/omap_dev info\n", __func__);
0404     return -ENODEV;
0405 }
0406 
0407 static int _od_fail_runtime_resume(struct device *dev)
0408 {
0409     dev_warn(dev, "%s: FIXME: missing hwmod/omap_dev info\n", __func__);
0410     return -ENODEV;
0411 }
0412 
0413 #endif
0414 
0415 #ifdef CONFIG_SUSPEND
0416 static int _od_suspend_noirq(struct device *dev)
0417 {
0418     struct platform_device *pdev = to_platform_device(dev);
0419     struct omap_device *od = to_omap_device(pdev);
0420     int ret;
0421 
0422     /* Don't attempt late suspend on a driver that is not bound */
0423     if (od->_driver_status != BUS_NOTIFY_BOUND_DRIVER)
0424         return 0;
0425 
0426     ret = pm_generic_suspend_noirq(dev);
0427 
0428     if (!ret && !pm_runtime_status_suspended(dev)) {
0429         if (pm_generic_runtime_suspend(dev) == 0) {
0430             omap_device_idle(pdev);
0431             od->flags |= OMAP_DEVICE_SUSPENDED;
0432         }
0433     }
0434 
0435     return ret;
0436 }
0437 
0438 static int _od_resume_noirq(struct device *dev)
0439 {
0440     struct platform_device *pdev = to_platform_device(dev);
0441     struct omap_device *od = to_omap_device(pdev);
0442 
0443     if (od->flags & OMAP_DEVICE_SUSPENDED) {
0444         od->flags &= ~OMAP_DEVICE_SUSPENDED;
0445         omap_device_enable(pdev);
0446         pm_generic_runtime_resume(dev);
0447     }
0448 
0449     return pm_generic_resume_noirq(dev);
0450 }
0451 #else
0452 #define _od_suspend_noirq NULL
0453 #define _od_resume_noirq NULL
0454 #endif
0455 
0456 struct dev_pm_domain omap_device_fail_pm_domain = {
0457     .ops = {
0458         SET_RUNTIME_PM_OPS(_od_fail_runtime_suspend,
0459                    _od_fail_runtime_resume, NULL)
0460     }
0461 };
0462 
0463 struct dev_pm_domain omap_device_pm_domain = {
0464     .ops = {
0465         SET_RUNTIME_PM_OPS(_od_runtime_suspend, _od_runtime_resume,
0466                    NULL)
0467         USE_PLATFORM_PM_SLEEP_OPS
0468         SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(_od_suspend_noirq,
0469                           _od_resume_noirq)
0470     }
0471 };
0472 
0473 /* Public functions for use by device drivers through struct platform_data */
0474 
0475 /**
0476  * omap_device_enable - fully activate an omap_device
0477  * @pdev: the platform device to activate
0478  *
0479  * Do whatever is necessary for the hwmods underlying omap_device @od
0480  * to be accessible and ready to operate.  This generally involves
0481  * enabling clocks, setting SYSCONFIG registers; and in the future may
0482  * involve remuxing pins.  Device drivers should call this function
0483  * indirectly via pm_runtime_get*().  Returns -EINVAL if called when
0484  * the omap_device is already enabled, or passes along the return
0485  * value of _omap_device_enable_hwmods().
0486  */
0487 int omap_device_enable(struct platform_device *pdev)
0488 {
0489     int ret;
0490     struct omap_device *od;
0491 
0492     od = to_omap_device(pdev);
0493 
0494     if (od->_state == OMAP_DEVICE_STATE_ENABLED) {
0495         dev_warn(&pdev->dev,
0496              "omap_device: %s() called from invalid state %d\n",
0497              __func__, od->_state);
0498         return -EINVAL;
0499     }
0500 
0501     ret = _omap_device_enable_hwmods(od);
0502 
0503     if (ret == 0)
0504         od->_state = OMAP_DEVICE_STATE_ENABLED;
0505 
0506     return ret;
0507 }
0508 
0509 /**
0510  * omap_device_idle - idle an omap_device
0511  * @pdev: The platform_device (omap_device) to idle
0512  *
0513  * Idle omap_device @od.  Device drivers call this function indirectly
0514  * via pm_runtime_put*().  Returns -EINVAL if the omap_device is not
0515  * currently enabled, or passes along the return value of
0516  * _omap_device_idle_hwmods().
0517  */
0518 int omap_device_idle(struct platform_device *pdev)
0519 {
0520     int ret;
0521     struct omap_device *od;
0522 
0523     od = to_omap_device(pdev);
0524 
0525     if (od->_state != OMAP_DEVICE_STATE_ENABLED) {
0526         dev_warn(&pdev->dev,
0527              "omap_device: %s() called from invalid state %d\n",
0528              __func__, od->_state);
0529         return -EINVAL;
0530     }
0531 
0532     ret = _omap_device_idle_hwmods(od);
0533 
0534     if (ret == 0)
0535         od->_state = OMAP_DEVICE_STATE_IDLE;
0536 
0537     return ret;
0538 }
0539 
0540 /**
0541  * omap_device_assert_hardreset - set a device's hardreset line
0542  * @pdev: struct platform_device * to reset
0543  * @name: const char * name of the reset line
0544  *
0545  * Set the hardreset line identified by @name on the IP blocks
0546  * associated with the hwmods backing the platform_device @pdev.  All
0547  * of the hwmods associated with @pdev must have the same hardreset
0548  * line linked to them for this to work.  Passes along the return value
0549  * of omap_hwmod_assert_hardreset() in the event of any failure, or
0550  * returns 0 upon success.
0551  */
0552 int omap_device_assert_hardreset(struct platform_device *pdev, const char *name)
0553 {
0554     struct omap_device *od = to_omap_device(pdev);
0555     int ret = 0;
0556     int i;
0557 
0558     for (i = 0; i < od->hwmods_cnt; i++) {
0559         ret = omap_hwmod_assert_hardreset(od->hwmods[i], name);
0560         if (ret)
0561             break;
0562     }
0563 
0564     return ret;
0565 }
0566 
0567 /**
0568  * omap_device_deassert_hardreset - release a device's hardreset line
0569  * @pdev: struct platform_device * to reset
0570  * @name: const char * name of the reset line
0571  *
0572  * Release the hardreset line identified by @name on the IP blocks
0573  * associated with the hwmods backing the platform_device @pdev.  All
0574  * of the hwmods associated with @pdev must have the same hardreset
0575  * line linked to them for this to work.  Passes along the return
0576  * value of omap_hwmod_deassert_hardreset() in the event of any
0577  * failure, or returns 0 upon success.
0578  */
0579 int omap_device_deassert_hardreset(struct platform_device *pdev,
0580                    const char *name)
0581 {
0582     struct omap_device *od = to_omap_device(pdev);
0583     int ret = 0;
0584     int i;
0585 
0586     for (i = 0; i < od->hwmods_cnt; i++) {
0587         ret = omap_hwmod_deassert_hardreset(od->hwmods[i], name);
0588         if (ret)
0589             break;
0590     }
0591 
0592     return ret;
0593 }
0594 
0595 /**
0596  * omap_device_get_by_hwmod_name() - convert a hwmod name to
0597  * device pointer.
0598  * @oh_name: name of the hwmod device
0599  *
0600  * Returns back a struct device * pointer associated with a hwmod
0601  * device represented by a hwmod_name
0602  */
0603 struct device *omap_device_get_by_hwmod_name(const char *oh_name)
0604 {
0605     struct omap_hwmod *oh;
0606 
0607     if (!oh_name) {
0608         WARN(1, "%s: no hwmod name!\n", __func__);
0609         return ERR_PTR(-EINVAL);
0610     }
0611 
0612     oh = omap_hwmod_lookup(oh_name);
0613     if (!oh) {
0614         WARN(1, "%s: no hwmod for %s\n", __func__,
0615             oh_name);
0616         return ERR_PTR(-ENODEV);
0617     }
0618     if (!oh->od) {
0619         WARN(1, "%s: no omap_device for %s\n", __func__,
0620             oh_name);
0621         return ERR_PTR(-ENODEV);
0622     }
0623 
0624     return &oh->od->pdev->dev;
0625 }
0626 
0627 static struct notifier_block platform_nb = {
0628     .notifier_call = _omap_device_notifier_call,
0629 };
0630 
0631 static int __init omap_device_init(void)
0632 {
0633     bus_register_notifier(&platform_bus_type, &platform_nb);
0634     return 0;
0635 }
0636 omap_postcore_initcall(omap_device_init);
0637 
0638 /**
0639  * omap_device_late_idle - idle devices without drivers
0640  * @dev: struct device * associated with omap_device
0641  * @data: unused
0642  *
0643  * Check the driver bound status of this device, and idle it
0644  * if there is no driver attached.
0645  */
0646 static int __init omap_device_late_idle(struct device *dev, void *data)
0647 {
0648     struct platform_device *pdev = to_platform_device(dev);
0649     struct omap_device *od = to_omap_device(pdev);
0650     int i;
0651 
0652     if (!od)
0653         return 0;
0654 
0655     /*
0656      * If omap_device state is enabled, but has no driver bound,
0657      * idle it.
0658      */
0659 
0660     /*
0661      * Some devices (like memory controllers) are always kept
0662      * enabled, and should not be idled even with no drivers.
0663      */
0664     for (i = 0; i < od->hwmods_cnt; i++)
0665         if (od->hwmods[i]->flags & HWMOD_INIT_NO_IDLE)
0666             return 0;
0667 
0668     if (od->_driver_status != BUS_NOTIFY_BOUND_DRIVER &&
0669         od->_driver_status != BUS_NOTIFY_BIND_DRIVER) {
0670         if (od->_state == OMAP_DEVICE_STATE_ENABLED) {
0671             dev_warn(dev, "%s: enabled but no driver.  Idling\n",
0672                  __func__);
0673             omap_device_idle(pdev);
0674         }
0675     }
0676 
0677     return 0;
0678 }
0679 
0680 static int __init omap_device_late_init(void)
0681 {
0682     bus_for_each_dev(&platform_bus_type, NULL, NULL, omap_device_late_idle);
0683 
0684     return 0;
0685 }
0686 omap_late_initcall_sync(omap_device_late_init);
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