// SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause
/*
 * Copyright (c) 2014 Raspberry Pi (Trading) Ltd. All rights reserved.
 * Copyright (c) 2010-2012 Broadcom. All rights reserved.
 */

#include <linux/debugfs.h>
#include <linux/raspberrypi/vchiq_core.h>
#include <linux/raspberrypi/vchiq_arm.h>
#include <linux/raspberrypi/vchiq_debugfs.h>

#ifdef CONFIG_DEBUG_FS

#define DEBUGFS_WRITE_BUF_SIZE 256

/* Global 'vchiq' debugfs and clients entry used by all instances */
static struct dentry *vchiq_dbg_dir;
static struct dentry *vchiq_dbg_clients;

static int debugfs_usecount_show(struct seq_file *f, void *offset)
{
        struct vchiq_instance *instance = f->private;
        int use_count;

        use_count = vchiq_instance_get_use_count(instance);
        seq_printf(f, "%d\n", use_count);

        return 0;
}
DEFINE_SHOW_ATTRIBUTE(debugfs_usecount);

static int debugfs_trace_show(struct seq_file *f, void *offset)
{
        struct vchiq_instance *instance = f->private;
        int trace;

        trace = vchiq_instance_get_trace(instance);
        seq_printf(f, "%s\n", trace ? "Y" : "N");

        return 0;
}

static int vchiq_dump_show(struct seq_file *f, void *offset)
{
        struct vchiq_state *state = f->private;

        vchiq_dump_state(f, state);

        return 0;
}
DEFINE_SHOW_ATTRIBUTE(vchiq_dump);

static int debugfs_trace_open(struct inode *inode, struct file *file)
{
        return single_open(file, debugfs_trace_show, inode->i_private);
}

static ssize_t debugfs_trace_write(struct file *file,
        const char __user *buffer,
        size_t count, loff_t *ppos)
{
        struct seq_file *f = (struct seq_file *)file->private_data;
        struct vchiq_instance *instance = f->private;
        char firstchar;

        if (copy_from_user(&firstchar, buffer, 1))
                return -EFAULT;

        switch (firstchar) {
        case 'Y':
        case 'y':
        case '1':
                vchiq_instance_set_trace(instance, 1);
                break;
        case 'N':
        case 'n':
        case '0':
                vchiq_instance_set_trace(instance, 0);
                break;
        default:
                break;
        }

        *ppos += count;

        return count;
}

static const struct file_operations debugfs_trace_fops = {
        .owner          = THIS_MODULE,
        .open           = debugfs_trace_open,
        .write          = debugfs_trace_write,
        .read           = seq_read,
        .llseek         = seq_lseek,
        .release        = single_release,
};

/* add an instance (process) to the debugfs entries */
void vchiq_debugfs_add_instance(struct vchiq_instance *instance)
{
        char pidstr[16];
        struct dentry *top;

        snprintf(pidstr, sizeof(pidstr), "%d",
                 vchiq_instance_get_pid(instance));

        top = debugfs_create_dir(pidstr, vchiq_dbg_clients);

        debugfs_create_file("use_count", 0444, top, instance,
                            &debugfs_usecount_fops);
        debugfs_create_file("trace", 0644, top, instance, &debugfs_trace_fops);

        vchiq_instance_get_debugfs_node(instance)->dentry = top;
}

void vchiq_debugfs_remove_instance(struct vchiq_instance *instance)
{
        struct vchiq_debugfs_node *node =
                                vchiq_instance_get_debugfs_node(instance);

        debugfs_remove_recursive(node->dentry);
}

void vchiq_debugfs_init(struct vchiq_state *state)
{
        vchiq_dbg_dir = debugfs_create_dir("vchiq", NULL);
        vchiq_dbg_clients = debugfs_create_dir("clients", vchiq_dbg_dir);

        debugfs_create_file("state", S_IFREG | 0444, vchiq_dbg_dir, state,
                            &vchiq_dump_fops);
}

/* remove all the debugfs entries */
void vchiq_debugfs_deinit(void)
{
        debugfs_remove_recursive(vchiq_dbg_dir);
}

#else /* CONFIG_DEBUG_FS */

void vchiq_debugfs_init(struct vchiq_state *state)
{
}

void vchiq_debugfs_deinit(void)
{
}

void vchiq_debugfs_add_instance(struct vchiq_instance *instance)
{
}

void vchiq_debugfs_remove_instance(struct vchiq_instance *instance)
{
}

#endif /* CONFIG_DEBUG_FS */