Merge tag 'trace-printf-v6.13' of git://git.kernel.org/pub/scm/linux/kernel/git/trace...

[drm/drm-misc.git] / drivers / bus / fsl-mc / dprc-driver.c

// SPDX-License-Identifier: GPL-2.0
/*
 * Freescale data path resource container (DPRC) driver
 *
 * Copyright (C) 2014-2016 Freescale Semiconductor, Inc.
 * Copyright 2019-2020 NXP
 * Author: German Rivera <German.Rivera@freescale.com>
 *
 */

#include <linux/module.h>
#include <linux/slab.h>
#include <linux/interrupt.h>
#include <linux/fsl/mc.h>

#include "fsl-mc-private.h"

#define FSL_MC_DPRC_DRIVER_NAME    "fsl_mc_dprc"

struct fsl_mc_child_objs {
        int child_count;
        struct fsl_mc_obj_desc *child_array;
};

static bool fsl_mc_device_match(struct fsl_mc_device *mc_dev,
                                struct fsl_mc_obj_desc *obj_desc)
{
        return mc_dev->obj_desc.id == obj_desc->id &&
               strcmp(mc_dev->obj_desc.type, obj_desc->type) == 0;
}

static bool fsl_mc_obj_desc_is_allocatable(struct fsl_mc_obj_desc *obj)
{
        if (strcmp(obj->type, "dpmcp") == 0 ||
            strcmp(obj->type, "dpcon") == 0 ||
            strcmp(obj->type, "dpbp") == 0)
                return true;
        else
                return false;
}

static int __fsl_mc_device_remove_if_not_in_mc(struct device *dev, void *data)
{
        int i;
        struct fsl_mc_child_objs *objs;
        struct fsl_mc_device *mc_dev;

        if (!dev_is_fsl_mc(dev))
                return 0;

        mc_dev = to_fsl_mc_device(dev);
        objs = data;

        for (i = 0; i < objs->child_count; i++) {
                struct fsl_mc_obj_desc *obj_desc = &objs->child_array[i];

                if (strlen(obj_desc->type) != 0 &&
                    fsl_mc_device_match(mc_dev, obj_desc))
                        break;
        }

        if (i == objs->child_count)
                fsl_mc_device_remove(mc_dev);

        return 0;
}

static int __fsl_mc_device_remove(struct device *dev, void *data)
{
        if (!dev_is_fsl_mc(dev))
                return 0;

        fsl_mc_device_remove(to_fsl_mc_device(dev));
        return 0;
}

/**
 * dprc_remove_devices - Removes devices for objects removed from a DPRC
 *
 * @mc_bus_dev: pointer to the fsl-mc device that represents a DPRC object
 * @obj_desc_array: array of object descriptors for child objects currently
 * present in the DPRC in the MC.
 * @num_child_objects_in_mc: number of entries in obj_desc_array
 *
 * Synchronizes the state of the Linux bus driver with the actual state of
 * the MC by removing devices that represent MC objects that have
 * been dynamically removed in the physical DPRC.
 */
void dprc_remove_devices(struct fsl_mc_device *mc_bus_dev,
                         struct fsl_mc_obj_desc *obj_desc_array,
                         int num_child_objects_in_mc)
{
        if (num_child_objects_in_mc != 0) {
                /*
                 * Remove child objects that are in the DPRC in Linux,
                 * but not in the MC:
                 */
                struct fsl_mc_child_objs objs;

                objs.child_count = num_child_objects_in_mc;
                objs.child_array = obj_desc_array;
                device_for_each_child(&mc_bus_dev->dev, &objs,
                                      __fsl_mc_device_remove_if_not_in_mc);
        } else {
                /*
                 * There are no child objects for this DPRC in the MC.
                 * So, remove all the child devices from Linux:
                 */
                device_for_each_child(&mc_bus_dev->dev, NULL,
                                      __fsl_mc_device_remove);
        }
}
EXPORT_SYMBOL_GPL(dprc_remove_devices);

static int __fsl_mc_device_match(struct device *dev, void *data)
{
        struct fsl_mc_obj_desc *obj_desc = data;
        struct fsl_mc_device *mc_dev = to_fsl_mc_device(dev);

        return fsl_mc_device_match(mc_dev, obj_desc);
}

struct fsl_mc_device *fsl_mc_device_lookup(struct fsl_mc_obj_desc *obj_desc,
                                           struct fsl_mc_device *mc_bus_dev)
{
        struct device *dev;

        dev = device_find_child(&mc_bus_dev->dev, obj_desc,
                                __fsl_mc_device_match);

        return dev ? to_fsl_mc_device(dev) : NULL;
}

/**
 * check_plugged_state_change - Check change in an MC object's plugged state
 *
 * @mc_dev: pointer to the fsl-mc device for a given MC object
 * @obj_desc: pointer to the MC object's descriptor in the MC
 *
 * If the plugged state has changed from unplugged to plugged, the fsl-mc
 * device is bound to the corresponding device driver.
 * If the plugged state has changed from plugged to unplugged, the fsl-mc
 * device is unbound from the corresponding device driver.
 */
static void check_plugged_state_change(struct fsl_mc_device *mc_dev,
                                       struct fsl_mc_obj_desc *obj_desc)
{
        int error;
        u32 plugged_flag_at_mc =
                        obj_desc->state & FSL_MC_OBJ_STATE_PLUGGED;

        if (plugged_flag_at_mc !=
            (mc_dev->obj_desc.state & FSL_MC_OBJ_STATE_PLUGGED)) {
                if (plugged_flag_at_mc) {
                        mc_dev->obj_desc.state |= FSL_MC_OBJ_STATE_PLUGGED;
                        error = device_attach(&mc_dev->dev);
                        if (error < 0) {
                                dev_err(&mc_dev->dev,
                                        "device_attach() failed: %d\n",
                                        error);
                        }
                } else {
                        mc_dev->obj_desc.state &= ~FSL_MC_OBJ_STATE_PLUGGED;
                        device_release_driver(&mc_dev->dev);
                }
        }
}

static void fsl_mc_obj_device_add(struct fsl_mc_device *mc_bus_dev,
                                  struct fsl_mc_obj_desc *obj_desc)
{
        int error;
        struct fsl_mc_device *child_dev;

        /*
         * Check if device is already known to Linux:
         */
        child_dev = fsl_mc_device_lookup(obj_desc, mc_bus_dev);
        if (child_dev) {
                check_plugged_state_change(child_dev, obj_desc);
                put_device(&child_dev->dev);
        } else {
                error = fsl_mc_device_add(obj_desc, NULL, &mc_bus_dev->dev,
                                          &child_dev);
                if (error < 0)
                        return;
        }
}

/**
 * dprc_add_new_devices - Adds devices to the logical bus for a DPRC
 *
 * @mc_bus_dev: pointer to the fsl-mc device that represents a DPRC object
 * @obj_desc_array: array of device descriptors for child devices currently
 * present in the physical DPRC.
 * @num_child_objects_in_mc: number of entries in obj_desc_array
 *
 * Synchronizes the state of the Linux bus driver with the actual
 * state of the MC by adding objects that have been newly discovered
 * in the physical DPRC.
 */
static void dprc_add_new_devices(struct fsl_mc_device *mc_bus_dev,
                                 struct fsl_mc_obj_desc *obj_desc_array,
                                 int num_child_objects_in_mc)
{
        int i;

        /* probe the allocable objects first */
        for (i = 0; i < num_child_objects_in_mc; i++) {
                struct fsl_mc_obj_desc *obj_desc = &obj_desc_array[i];

                if (strlen(obj_desc->type) > 0 &&
                    fsl_mc_obj_desc_is_allocatable(obj_desc))
                        fsl_mc_obj_device_add(mc_bus_dev, obj_desc);
        }

        for (i = 0; i < num_child_objects_in_mc; i++) {
                struct fsl_mc_obj_desc *obj_desc = &obj_desc_array[i];

                if (strlen(obj_desc->type) > 0 &&
                    !fsl_mc_obj_desc_is_allocatable(obj_desc))
                        fsl_mc_obj_device_add(mc_bus_dev, obj_desc);
        }
}

/**
 * dprc_scan_objects - Discover objects in a DPRC
 *
 * @mc_bus_dev: pointer to the fsl-mc device that represents a DPRC object
 * @alloc_interrupts: if true the function allocates the interrupt pool,
 * otherwise the interrupt allocation is delayed
 *
 * Detects objects added and removed from a DPRC and synchronizes the
 * state of the Linux bus driver, MC by adding and removing
 * devices accordingly.
 * Two types of devices can be found in a DPRC: allocatable objects (e.g.,
 * dpbp, dpmcp) and non-allocatable devices (e.g., dprc, dpni).
 * All allocatable devices needed to be probed before all non-allocatable
 * devices, to ensure that device drivers for non-allocatable
 * devices can allocate any type of allocatable devices.
 * That is, we need to ensure that the corresponding resource pools are
 * populated before they can get allocation requests from probe callbacks
 * of the device drivers for the non-allocatable devices.
 */
int dprc_scan_objects(struct fsl_mc_device *mc_bus_dev,
                      bool alloc_interrupts)
{
        int num_child_objects;
        int dprc_get_obj_failures;
        int error;
        unsigned int irq_count = mc_bus_dev->obj_desc.irq_count;
        struct fsl_mc_obj_desc *child_obj_desc_array = NULL;
        struct fsl_mc_bus *mc_bus = to_fsl_mc_bus(mc_bus_dev);

        error = dprc_get_obj_count(mc_bus_dev->mc_io,
                                   0,
                                   mc_bus_dev->mc_handle,
                                   &num_child_objects);
        if (error < 0) {
                dev_err(&mc_bus_dev->dev, "dprc_get_obj_count() failed: %d\n",
                        error);
                return error;
        }

        if (num_child_objects != 0) {
                int i;

                child_obj_desc_array =
                    devm_kmalloc_array(&mc_bus_dev->dev, num_child_objects,
                                       sizeof(*child_obj_desc_array),
                                       GFP_KERNEL);
                if (!child_obj_desc_array)
                        return -ENOMEM;

                /*
                 * Discover objects currently present in the physical DPRC:
                 */
                dprc_get_obj_failures = 0;
                for (i = 0; i < num_child_objects; i++) {
                        struct fsl_mc_obj_desc *obj_desc =
                            &child_obj_desc_array[i];

                        error = dprc_get_obj(mc_bus_dev->mc_io,
                                             0,
                                             mc_bus_dev->mc_handle,
                                             i, obj_desc);
                        if (error < 0) {
                                dev_err(&mc_bus_dev->dev,
                                        "dprc_get_obj(i=%d) failed: %d\n",
                                        i, error);
                                /*
                                 * Mark the obj entry as "invalid", by using the
                                 * empty string as obj type:
                                 */
                                obj_desc->type[0] = '\0';
                                obj_desc->id = error;
                                dprc_get_obj_failures++;
                                continue;
                        }

                        /*
                         * add a quirk for all versions of dpsec < 4.0...none
                         * are coherent regardless of what the MC reports.
                         */
                        if ((strcmp(obj_desc->type, "dpseci") == 0) &&
                            (obj_desc->ver_major < 4))
                                obj_desc->flags |=
                                        FSL_MC_OBJ_FLAG_NO_MEM_SHAREABILITY;

                        irq_count += obj_desc->irq_count;
                        dev_dbg(&mc_bus_dev->dev,
                                "Discovered object: type %s, id %d\n",
                                obj_desc->type, obj_desc->id);
                }

                if (dprc_get_obj_failures != 0) {
                        dev_err(&mc_bus_dev->dev,
                                "%d out of %d devices could not be retrieved\n",
                                dprc_get_obj_failures, num_child_objects);
                }
        }

        /*
         * Allocate IRQ's before binding the scanned devices with their
         * respective drivers.
         */
        if (dev_get_msi_domain(&mc_bus_dev->dev)) {
                if (irq_count > FSL_MC_IRQ_POOL_MAX_TOTAL_IRQS) {
                        dev_warn(&mc_bus_dev->dev,
                                 "IRQs needed (%u) exceed IRQs preallocated (%u)\n",
                                 irq_count, FSL_MC_IRQ_POOL_MAX_TOTAL_IRQS);
                }

                if (alloc_interrupts && !mc_bus->irq_resources) {
                        error = fsl_mc_populate_irq_pool(mc_bus_dev,
                                         FSL_MC_IRQ_POOL_MAX_TOTAL_IRQS);
                        if (error < 0)
                                return error;
                }
        }

        dprc_remove_devices(mc_bus_dev, child_obj_desc_array,
                            num_child_objects);

        dprc_add_new_devices(mc_bus_dev, child_obj_desc_array,
                             num_child_objects);

        if (child_obj_desc_array)
                devm_kfree(&mc_bus_dev->dev, child_obj_desc_array);

        return 0;
}

/**
 * dprc_scan_container - Scans a physical DPRC and synchronizes Linux bus state
 *
 * @mc_bus_dev: pointer to the fsl-mc device that represents a DPRC object
 * @alloc_interrupts: if true the function allocates the interrupt pool,
 *                    otherwise the interrupt allocation is delayed
 * Scans the physical DPRC and synchronizes the state of the Linux
 * bus driver with the actual state of the MC by adding and removing
 * devices as appropriate.
 */
int dprc_scan_container(struct fsl_mc_device *mc_bus_dev,
                        bool alloc_interrupts)
{
        int error = 0;
        struct fsl_mc_bus *mc_bus = to_fsl_mc_bus(mc_bus_dev);

        fsl_mc_init_all_resource_pools(mc_bus_dev);

        /*
         * Discover objects in the DPRC:
         */
        mutex_lock(&mc_bus->scan_mutex);
        error = dprc_scan_objects(mc_bus_dev, alloc_interrupts);
        mutex_unlock(&mc_bus->scan_mutex);

        return error;
}
EXPORT_SYMBOL_GPL(dprc_scan_container);

/**
 * dprc_irq0_handler - Regular ISR for DPRC interrupt 0
 *
 * @irq_num: IRQ number of the interrupt being handled
 * @arg: Pointer to device structure
 */
static irqreturn_t dprc_irq0_handler(int irq_num, void *arg)
{
        return IRQ_WAKE_THREAD;
}

/**
 * dprc_irq0_handler_thread - Handler thread function for DPRC interrupt 0
 *
 * @irq_num: IRQ number of the interrupt being handled
 * @arg: Pointer to device structure
 */
static irqreturn_t dprc_irq0_handler_thread(int irq_num, void *arg)
{
        int error;
        u32 status;
        struct device *dev = arg;
        struct fsl_mc_device *mc_dev = to_fsl_mc_device(dev);
        struct fsl_mc_bus *mc_bus = to_fsl_mc_bus(mc_dev);
        struct fsl_mc_io *mc_io = mc_dev->mc_io;
        int irq = mc_dev->irqs[0]->virq;

        dev_dbg(dev, "DPRC IRQ %d triggered on CPU %u\n",
                irq_num, smp_processor_id());

        if (!(mc_dev->flags & FSL_MC_IS_DPRC))
                return IRQ_HANDLED;

        mutex_lock(&mc_bus->scan_mutex);
        if (irq != (u32)irq_num)
                goto out;

        status = 0;
        error = dprc_get_irq_status(mc_io, 0, mc_dev->mc_handle, 0,
                                    &status);
        if (error < 0) {
                dev_err(dev,
                        "dprc_get_irq_status() failed: %d\n", error);
                goto out;
        }

        error = dprc_clear_irq_status(mc_io, 0, mc_dev->mc_handle, 0,
                                      status);
        if (error < 0) {
                dev_err(dev,
                        "dprc_clear_irq_status() failed: %d\n", error);
                goto out;
        }

        if (status & (DPRC_IRQ_EVENT_OBJ_ADDED |
                      DPRC_IRQ_EVENT_OBJ_REMOVED |
                      DPRC_IRQ_EVENT_CONTAINER_DESTROYED |
                      DPRC_IRQ_EVENT_OBJ_DESTROYED |
                      DPRC_IRQ_EVENT_OBJ_CREATED)) {

                error = dprc_scan_objects(mc_dev, true);
                if (error < 0) {
                        /*
                         * If the error is -ENXIO, we ignore it, as it indicates
                         * that the object scan was aborted, as we detected that
                         * an object was removed from the DPRC in the MC, while
                         * we were scanning the DPRC.
                         */
                        if (error != -ENXIO) {
                                dev_err(dev, "dprc_scan_objects() failed: %d\n",
                                        error);
                        }

                        goto out;
                }
        }

out:
        mutex_unlock(&mc_bus->scan_mutex);
        return IRQ_HANDLED;
}

/*
 * Disable and clear interrupt for a given DPRC object
 */
int disable_dprc_irq(struct fsl_mc_device *mc_dev)
{
        struct fsl_mc_bus *mc_bus = to_fsl_mc_bus(mc_dev);
        int error;
        struct fsl_mc_io *mc_io = mc_dev->mc_io;

        /*
         * Disable generation of interrupt, while we configure it:
         */
        error = dprc_set_irq_enable(mc_io, 0, mc_dev->mc_handle, 0, 0);
        if (error < 0) {
                dev_err(&mc_dev->dev,
                        "Disabling DPRC IRQ failed: dprc_set_irq_enable() failed: %d\n",
                        error);
                return error;
        }

        /*
         * Disable all interrupt causes for the interrupt:
         */
        error = dprc_set_irq_mask(mc_io, 0, mc_dev->mc_handle, 0, 0x0);
        if (error < 0) {
                dev_err(&mc_dev->dev,
                        "Disabling DPRC IRQ failed: dprc_set_irq_mask() failed: %d\n",
                        error);
                return error;
        }

        /*
         * Clear any leftover interrupts:
         */
        error = dprc_clear_irq_status(mc_io, 0, mc_dev->mc_handle, 0, ~0x0U);
        if (error < 0) {
                dev_err(&mc_dev->dev,
                        "Disabling DPRC IRQ failed: dprc_clear_irq_status() failed: %d\n",
                        error);
                return error;
        }

        mc_bus->irq_enabled = 0;

        return 0;
}

int get_dprc_irq_state(struct fsl_mc_device *mc_dev)
{
        struct fsl_mc_bus *mc_bus = to_fsl_mc_bus(mc_dev);

        return mc_bus->irq_enabled;
}

static int register_dprc_irq_handler(struct fsl_mc_device *mc_dev)
{
        int error;
        struct fsl_mc_device_irq *irq = mc_dev->irqs[0];

        /*
         * NOTE: devm_request_threaded_irq() invokes the device-specific
         * function that programs the MSI physically in the device
         */
        error = devm_request_threaded_irq(&mc_dev->dev,
                                          irq->virq,
                                          dprc_irq0_handler,
                                          dprc_irq0_handler_thread,
                                          IRQF_NO_SUSPEND | IRQF_ONESHOT,
                                          dev_name(&mc_dev->dev),
                                          &mc_dev->dev);
        if (error < 0) {
                dev_err(&mc_dev->dev,
                        "devm_request_threaded_irq() failed: %d\n",
                        error);
                return error;
        }

        return 0;
}

int enable_dprc_irq(struct fsl_mc_device *mc_dev)
{
        struct fsl_mc_bus *mc_bus = to_fsl_mc_bus(mc_dev);
        int error;

        /*
         * Enable all interrupt causes for the interrupt:
         */
        error = dprc_set_irq_mask(mc_dev->mc_io, 0, mc_dev->mc_handle, 0,
                                  ~0x0u);
        if (error < 0) {
                dev_err(&mc_dev->dev,
                        "Enabling DPRC IRQ failed: dprc_set_irq_mask() failed: %d\n",
                        error);

                return error;
        }

        /*
         * Enable generation of the interrupt:
         */
        error = dprc_set_irq_enable(mc_dev->mc_io, 0, mc_dev->mc_handle, 0, 1);
        if (error < 0) {
                dev_err(&mc_dev->dev,
                        "Enabling DPRC IRQ failed: dprc_set_irq_enable() failed: %d\n",
                        error);

                return error;
        }

        mc_bus->irq_enabled = 1;

        return 0;
}

/*
 * Setup interrupt for a given DPRC device
 */
static int dprc_setup_irq(struct fsl_mc_device *mc_dev)
{
        int error;

        error = fsl_mc_allocate_irqs(mc_dev);
        if (error < 0)
                return error;

        error = disable_dprc_irq(mc_dev);
        if (error < 0)
                goto error_free_irqs;

        error = register_dprc_irq_handler(mc_dev);
        if (error < 0)
                goto error_free_irqs;

        error = enable_dprc_irq(mc_dev);
        if (error < 0)
                goto error_free_irqs;

        return 0;

error_free_irqs:
        fsl_mc_free_irqs(mc_dev);
        return error;
}

/**
 * dprc_setup - opens and creates a mc_io for DPRC
 *
 * @mc_dev: Pointer to fsl-mc device representing a DPRC
 *
 * It opens the physical DPRC in the MC.
 * It configures the DPRC portal used to communicate with MC
 */

int dprc_setup(struct fsl_mc_device *mc_dev)
{
        struct device *parent_dev = mc_dev->dev.parent;
        struct fsl_mc_bus *mc_bus = to_fsl_mc_bus(mc_dev);
        struct irq_domain *mc_msi_domain;
        bool mc_io_created = false;
        bool msi_domain_set = false;
        bool uapi_created = false;
        u16 major_ver, minor_ver;
        size_t region_size;
        int error;

        if (!is_fsl_mc_bus_dprc(mc_dev))
                return -EINVAL;

        if (dev_get_msi_domain(&mc_dev->dev))
                return -EINVAL;

        if (!mc_dev->mc_io) {
                /*
                 * This is a child DPRC:
                 */
                if (!dev_is_fsl_mc(parent_dev))
                        return -EINVAL;

                if (mc_dev->obj_desc.region_count == 0)
                        return -EINVAL;

                region_size = resource_size(mc_dev->regions);

                error = fsl_create_mc_io(&mc_dev->dev,
                                         mc_dev->regions[0].start,
                                         region_size,
                                         NULL,
                                         FSL_MC_IO_ATOMIC_CONTEXT_PORTAL,
                                         &mc_dev->mc_io);
                if (error < 0)
                        return error;

                mc_io_created = true;
        } else {
                error = fsl_mc_uapi_create_device_file(mc_bus);
                if (error < 0)
                        return -EPROBE_DEFER;
                uapi_created = true;
        }

        mc_msi_domain = fsl_mc_find_msi_domain(&mc_dev->dev);
        if (!mc_msi_domain) {
                dev_warn(&mc_dev->dev,
                         "WARNING: MC bus without interrupt support\n");
        } else {
                dev_set_msi_domain(&mc_dev->dev, mc_msi_domain);
                msi_domain_set = true;
        }

        error = dprc_open(mc_dev->mc_io, 0, mc_dev->obj_desc.id,
                          &mc_dev->mc_handle);
        if (error < 0) {
                dev_err(&mc_dev->dev, "dprc_open() failed: %d\n", error);
                goto error_cleanup_msi_domain;
        }

        error = dprc_get_attributes(mc_dev->mc_io, 0, mc_dev->mc_handle,
                                    &mc_bus->dprc_attr);
        if (error < 0) {
                dev_err(&mc_dev->dev, "dprc_get_attributes() failed: %d\n",
                        error);
                goto error_cleanup_open;
        }

        error = dprc_get_api_version(mc_dev->mc_io, 0,
                                     &major_ver,
                                     &minor_ver);
        if (error < 0) {
                dev_err(&mc_dev->dev, "dprc_get_api_version() failed: %d\n",
                        error);
                goto error_cleanup_open;
        }

        if (major_ver < DPRC_MIN_VER_MAJOR) {
                dev_err(&mc_dev->dev,
                        "ERROR: DPRC version %d.%d not supported\n",
                        major_ver, minor_ver);
                error = -ENOTSUPP;
                goto error_cleanup_open;
        }

        return 0;

error_cleanup_open:
        (void)dprc_close(mc_dev->mc_io, 0, mc_dev->mc_handle);

error_cleanup_msi_domain:
        if (msi_domain_set)
                dev_set_msi_domain(&mc_dev->dev, NULL);

        if (mc_io_created) {
                fsl_destroy_mc_io(mc_dev->mc_io);
                mc_dev->mc_io = NULL;
        }

        if (uapi_created)
                fsl_mc_uapi_remove_device_file(mc_bus);

        return error;
}
EXPORT_SYMBOL_GPL(dprc_setup);

/**
 * dprc_probe - callback invoked when a DPRC is being bound to this driver
 *
 * @mc_dev: Pointer to fsl-mc device representing a DPRC
 *
 * It opens the physical DPRC in the MC.
 * It scans the DPRC to discover the MC objects contained in it.
 * It creates the interrupt pool for the MC bus associated with the DPRC.
 * It configures the interrupts for the DPRC device itself.
 */
static int dprc_probe(struct fsl_mc_device *mc_dev)
{
        int error;

        error = dprc_setup(mc_dev);
        if (error < 0)
                return error;

        /*
         * Discover MC objects in DPRC object:
         */
        error = dprc_scan_container(mc_dev, true);
        if (error < 0)
                goto dprc_cleanup;

        /*
         * Configure interrupt for the DPRC object associated with this MC bus:
         */
        error = dprc_setup_irq(mc_dev);
        if (error < 0)
                goto scan_cleanup;

        dev_info(&mc_dev->dev, "DPRC device bound to driver");
        return 0;

scan_cleanup:
        device_for_each_child(&mc_dev->dev, NULL, __fsl_mc_device_remove);
dprc_cleanup:
        dprc_cleanup(mc_dev);
        return error;
}

/*
 * Tear down interrupt for a given DPRC object
 */
static void dprc_teardown_irq(struct fsl_mc_device *mc_dev)
{
        struct fsl_mc_device_irq *irq = mc_dev->irqs[0];

        (void)disable_dprc_irq(mc_dev);

        devm_free_irq(&mc_dev->dev, irq->virq, &mc_dev->dev);

        fsl_mc_free_irqs(mc_dev);
}

/**
 * dprc_cleanup - function that cleanups a DPRC
 *
 * @mc_dev: Pointer to fsl-mc device representing the DPRC
 *
 * It closes the DPRC device in the MC.
 * It destroys the interrupt pool associated with this MC bus.
 */

int dprc_cleanup(struct fsl_mc_device *mc_dev)
{
        struct fsl_mc_bus *mc_bus = to_fsl_mc_bus(mc_dev);
        int error;

        /* this function should be called only for DPRCs, it
         * is an error to call it for regular objects
         */
        if (!is_fsl_mc_bus_dprc(mc_dev))
                return -EINVAL;

        if (dev_get_msi_domain(&mc_dev->dev)) {
                fsl_mc_cleanup_irq_pool(mc_dev);
                dev_set_msi_domain(&mc_dev->dev, NULL);
        }

        fsl_mc_cleanup_all_resource_pools(mc_dev);

        /* if this step fails we cannot go further with cleanup as there is no way of
         * communicating with the firmware
         */
        if (!mc_dev->mc_io) {
                dev_err(&mc_dev->dev, "mc_io is NULL, tear down cannot be performed in firmware\n");
                return -EINVAL;
        }

        error = dprc_close(mc_dev->mc_io, 0, mc_dev->mc_handle);
        if (error < 0)
                dev_err(&mc_dev->dev, "dprc_close() failed: %d\n", error);

        if (!fsl_mc_is_root_dprc(&mc_dev->dev)) {
                fsl_destroy_mc_io(mc_dev->mc_io);
                mc_dev->mc_io = NULL;
        } else {
                fsl_mc_uapi_remove_device_file(mc_bus);
        }

        return 0;
}
EXPORT_SYMBOL_GPL(dprc_cleanup);

/**
 * dprc_remove - callback invoked when a DPRC is being unbound from this driver
 *
 * @mc_dev: Pointer to fsl-mc device representing the DPRC
 *
 * It removes the DPRC's child objects from Linux (not from the MC) and
 * closes the DPRC device in the MC.
 * It tears down the interrupts that were configured for the DPRC device.
 * It destroys the interrupt pool associated with this MC bus.
 */
static void dprc_remove(struct fsl_mc_device *mc_dev)
{
        struct fsl_mc_bus *mc_bus = to_fsl_mc_bus(mc_dev);

        if (!mc_bus->irq_resources) {
                dev_err(&mc_dev->dev, "No irq resources, so unbinding the device failed\n");
                return;
        }

        if (dev_get_msi_domain(&mc_dev->dev))
                dprc_teardown_irq(mc_dev);

        device_for_each_child(&mc_dev->dev, NULL, __fsl_mc_device_remove);

        dprc_cleanup(mc_dev);

        dev_info(&mc_dev->dev, "DPRC device unbound from driver");
}

static const struct fsl_mc_device_id match_id_table[] = {
        {
         .vendor = FSL_MC_VENDOR_FREESCALE,
         .obj_type = "dprc"},
        {.vendor = 0x0},
};

static struct fsl_mc_driver dprc_driver = {
        .driver = {
                   .name = FSL_MC_DPRC_DRIVER_NAME,
                   .owner = THIS_MODULE,
                   .pm = NULL,
                   },
        .match_id_table = match_id_table,
        .probe = dprc_probe,
        .remove = dprc_remove,
};

int __init dprc_driver_init(void)
{
        return fsl_mc_driver_register(&dprc_driver);
}

void dprc_driver_exit(void)
{
        fsl_mc_driver_unregister(&dprc_driver);
}