// SPDX-License-Identifier: GPL-2.0
/*
 * arch/sh/drivers/dma/dma-sysfs.c
 *
 * sysfs interface for SH DMA API
 *
 * Copyright (C) 2004 - 2006  Paul Mundt
 */
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/stat.h>
#include <linux/device.h>
#include <linux/platform_device.h>
#include <linux/err.h>
#include <linux/string.h>
#include <asm/dma.h>

static const struct bus_type dma_subsys = {
        .name = "dma",
        .dev_name = "dma",
};

static ssize_t dma_show_devices(struct device *dev,
                                struct device_attribute *attr, char *buf)
{
        ssize_t len = 0;
        int i;

        for (i = 0; i < 16; i++) {
                struct dma_info *info = get_dma_info(i);
                struct dma_channel *channel = get_dma_channel(i);

                if (unlikely(!info) || !channel)
                        continue;

                len += sprintf(buf + len, "%2d: %14s    %s\n",
                               channel->chan, info->name,
                               channel->dev_id);
        }

        return len;
}

static DEVICE_ATTR(devices, S_IRUGO, dma_show_devices, NULL);

static int __init dma_subsys_init(void)
{
        struct device *dev_root;
        int ret;

        ret = subsys_system_register(&dma_subsys, NULL);
        if (unlikely(ret))
                return ret;

        dev_root = bus_get_dev_root(&dma_subsys);
        if (dev_root) {
                ret = device_create_file(dev_root, &dev_attr_devices);
                put_device(dev_root);
        }
        return ret;
}
postcore_initcall(dma_subsys_init);

static ssize_t dma_show_dev_id(struct device *dev,
                                struct device_attribute *attr, char *buf)
{
        struct dma_channel *channel = to_dma_channel(dev);
        return sprintf(buf, "%s\n", channel->dev_id);
}

static ssize_t dma_store_dev_id(struct device *dev,
                                struct device_attribute *attr,
                                const char *buf, size_t count)
{
        struct dma_channel *channel = to_dma_channel(dev);
        strcpy(channel->dev_id, buf);
        return count;
}

static DEVICE_ATTR(dev_id, S_IRUGO | S_IWUSR, dma_show_dev_id, dma_store_dev_id);

static ssize_t dma_store_config(struct device *dev,
                                struct device_attribute *attr,
                                const char *buf, size_t count)
{
        struct dma_channel *channel = to_dma_channel(dev);
        unsigned long config;

        config = simple_strtoul(buf, NULL, 0);
        dma_configure_channel(channel->vchan, config);

        return count;
}

static DEVICE_ATTR(config, S_IWUSR, NULL, dma_store_config);

static ssize_t dma_show_mode(struct device *dev,
                                struct device_attribute *attr, char *buf)
{
        struct dma_channel *channel = to_dma_channel(dev);
        return sprintf(buf, "0x%08x\n", channel->mode);
}

static ssize_t dma_store_mode(struct device *dev,
                              struct device_attribute *attr,
                              const char *buf, size_t count)
{
        struct dma_channel *channel = to_dma_channel(dev);
        channel->mode = simple_strtoul(buf, NULL, 0);
        return count;
}

static DEVICE_ATTR(mode, S_IRUGO | S_IWUSR, dma_show_mode, dma_store_mode);

#define dma_ro_attr(field, fmt)                                         \
static ssize_t dma_show_##field(struct device *dev,             \
                                struct device_attribute *attr, char *buf)\
{                                                                       \
        struct dma_channel *channel = to_dma_channel(dev);              \
        return sprintf(buf, fmt, channel->field);                       \
}                                                                       \
static DEVICE_ATTR(field, S_IRUGO, dma_show_##field, NULL);

dma_ro_attr(count, "0x%08x\n");
dma_ro_attr(flags, "0x%08lx\n");

int dma_create_sysfs_files(struct dma_channel *chan, struct dma_info *info)
{
        struct device *dev = &chan->dev;
        char name[16];
        int ret;

        dev->id  = chan->vchan;
        dev->bus = &dma_subsys;

        ret = device_register(dev);
        if (ret)
                return ret;

        ret |= device_create_file(dev, &dev_attr_dev_id);
        ret |= device_create_file(dev, &dev_attr_count);
        ret |= device_create_file(dev, &dev_attr_mode);
        ret |= device_create_file(dev, &dev_attr_flags);
        ret |= device_create_file(dev, &dev_attr_config);

        if (unlikely(ret)) {
                dev_err(&info->pdev->dev, "Failed creating attrs\n");
                return ret;
        }

        snprintf(name, sizeof(name), "dma%d", chan->chan);
        return sysfs_create_link(&info->pdev->dev.kobj, &dev->kobj, name);
}

void dma_remove_sysfs_files(struct dma_channel *chan, struct dma_info *info)
{
        struct device *dev = &chan->dev;
        char name[16];

        device_remove_file(dev, &dev_attr_dev_id);
        device_remove_file(dev, &dev_attr_count);
        device_remove_file(dev, &dev_attr_mode);
        device_remove_file(dev, &dev_attr_flags);
        device_remove_file(dev, &dev_attr_config);

        snprintf(name, sizeof(name), "dma%d", chan->chan);
        sysfs_remove_link(&info->pdev->dev.kobj, name);

        device_unregister(dev);
}