// SPDX-License-Identifier: GPL-2.0
/*
 * Greybus bundles
 *
 * Copyright 2014-2015 Google Inc.
 * Copyright 2014-2015 Linaro Ltd.
 */

#include <linux/greybus.h>
#include "greybus_trace.h"

static ssize_t bundle_class_show(struct device *dev,
                                 struct device_attribute *attr, char *buf)
{
        struct gb_bundle *bundle = to_gb_bundle(dev);

        return sprintf(buf, "0x%02x\n", bundle->class);
}
static DEVICE_ATTR_RO(bundle_class);

static ssize_t bundle_id_show(struct device *dev,
                              struct device_attribute *attr, char *buf)
{
        struct gb_bundle *bundle = to_gb_bundle(dev);

        return sprintf(buf, "%u\n", bundle->id);
}
static DEVICE_ATTR_RO(bundle_id);

static ssize_t state_show(struct device *dev, struct device_attribute *attr,
                          char *buf)
{
        struct gb_bundle *bundle = to_gb_bundle(dev);

        if (!bundle->state)
                return sprintf(buf, "\n");

        return sprintf(buf, "%s\n", bundle->state);
}

static ssize_t state_store(struct device *dev, struct device_attribute *attr,
                           const char *buf, size_t size)
{
        struct gb_bundle *bundle = to_gb_bundle(dev);

        kfree(bundle->state);
        bundle->state = kstrdup(buf, GFP_KERNEL);
        if (!bundle->state)
                return -ENOMEM;

        /* Tell userspace that the file contents changed */
        sysfs_notify(&bundle->dev.kobj, NULL, "state");

        return size;
}
static DEVICE_ATTR_RW(state);

static struct attribute *bundle_attrs[] = {
        &dev_attr_bundle_class.attr,
        &dev_attr_bundle_id.attr,
        &dev_attr_state.attr,
        NULL,
};

ATTRIBUTE_GROUPS(bundle);

static struct gb_bundle *gb_bundle_find(struct gb_interface *intf,
                                        u8 bundle_id)
{
        struct gb_bundle *bundle;

        list_for_each_entry(bundle, &intf->bundles, links) {
                if (bundle->id == bundle_id)
                        return bundle;
        }

        return NULL;
}

static void gb_bundle_release(struct device *dev)
{
        struct gb_bundle *bundle = to_gb_bundle(dev);

        trace_gb_bundle_release(bundle);

        kfree(bundle->state);
        kfree(bundle->cport_desc);
        kfree(bundle);
}

#ifdef CONFIG_PM
static void gb_bundle_disable_all_connections(struct gb_bundle *bundle)
{
        struct gb_connection *connection;

        list_for_each_entry(connection, &bundle->connections, bundle_links)
                gb_connection_disable(connection);
}

static void gb_bundle_enable_all_connections(struct gb_bundle *bundle)
{
        struct gb_connection *connection;

        list_for_each_entry(connection, &bundle->connections, bundle_links)
                gb_connection_enable(connection);
}

static int gb_bundle_suspend(struct device *dev)
{
        struct gb_bundle *bundle = to_gb_bundle(dev);
        const struct dev_pm_ops *pm = dev->driver->pm;
        int ret;

        if (pm && pm->runtime_suspend) {
                ret = pm->runtime_suspend(&bundle->dev);
                if (ret)
                        return ret;
        } else {
                gb_bundle_disable_all_connections(bundle);
        }

        ret = gb_control_bundle_suspend(bundle->intf->control, bundle->id);
        if (ret) {
                if (pm && pm->runtime_resume)
                        ret = pm->runtime_resume(dev);
                else
                        gb_bundle_enable_all_connections(bundle);

                return ret;
        }

        return 0;
}

static int gb_bundle_resume(struct device *dev)
{
        struct gb_bundle *bundle = to_gb_bundle(dev);
        const struct dev_pm_ops *pm = dev->driver->pm;
        int ret;

        ret = gb_control_bundle_resume(bundle->intf->control, bundle->id);
        if (ret)
                return ret;

        if (pm && pm->runtime_resume) {
                ret = pm->runtime_resume(dev);
                if (ret)
                        return ret;
        } else {
                gb_bundle_enable_all_connections(bundle);
        }

        return 0;
}

static int gb_bundle_idle(struct device *dev)
{
        pm_runtime_mark_last_busy(dev);
        pm_request_autosuspend(dev);

        return 0;
}
#endif

static const struct dev_pm_ops gb_bundle_pm_ops = {
        SET_RUNTIME_PM_OPS(gb_bundle_suspend, gb_bundle_resume, gb_bundle_idle)
};

const struct device_type greybus_bundle_type = {
        .name =         "greybus_bundle",
        .release =      gb_bundle_release,
        .pm =           &gb_bundle_pm_ops,
};

/*
 * Create a gb_bundle structure to represent a discovered
 * bundle.  Returns a pointer to the new bundle or a null
 * pointer if a failure occurs due to memory exhaustion.
 */
struct gb_bundle *gb_bundle_create(struct gb_interface *intf, u8 bundle_id,
                                   u8 class)
{
        struct gb_bundle *bundle;

        if (bundle_id == BUNDLE_ID_NONE) {
                dev_err(&intf->dev, "can't use bundle id %u\n", bundle_id);
                return NULL;
        }

        /*
         * Reject any attempt to reuse a bundle id.  We initialize
         * these serially, so there's no need to worry about keeping
         * the interface bundle list locked here.
         */
        if (gb_bundle_find(intf, bundle_id)) {
                dev_err(&intf->dev, "duplicate bundle id %u\n", bundle_id);
                return NULL;
        }

        bundle = kzalloc_obj(*bundle);
        if (!bundle)
                return NULL;

        bundle->intf = intf;
        bundle->id = bundle_id;
        bundle->class = class;
        INIT_LIST_HEAD(&bundle->connections);

        bundle->dev.parent = &intf->dev;
        bundle->dev.bus = &greybus_bus_type;
        bundle->dev.type = &greybus_bundle_type;
        bundle->dev.groups = bundle_groups;
        bundle->dev.dma_mask = intf->dev.dma_mask;
        device_initialize(&bundle->dev);
        dev_set_name(&bundle->dev, "%s.%d", dev_name(&intf->dev), bundle_id);

        list_add(&bundle->links, &intf->bundles);

        trace_gb_bundle_create(bundle);

        return bundle;
}

int gb_bundle_add(struct gb_bundle *bundle)
{
        int ret;

        ret = device_add(&bundle->dev);
        if (ret) {
                dev_err(&bundle->dev, "failed to register bundle: %d\n", ret);
                return ret;
        }

        trace_gb_bundle_add(bundle);

        return 0;
}

/*
 * Tear down a previously set up bundle.
 */
void gb_bundle_destroy(struct gb_bundle *bundle)
{
        trace_gb_bundle_destroy(bundle);

        if (device_is_registered(&bundle->dev))
                device_del(&bundle->dev);

        list_del(&bundle->links);

        put_device(&bundle->dev);
}