// SPDX-License-Identifier: GPL-2.0
#include <linux/dcache.h>
#include <linux/debugfs.h>
#include <linux/delay.h>
#include <linux/hardirq.h>
#include <linux/mm.h>
#include <linux/string.h>
#include <linux/slab.h>
#include <linux/export.h>

#include "decl.h"
#include "cmd.h"
#include "debugfs.h"

static struct dentry *lbs_dir;
static char *szStates[] = {
        "Connected",
        "Disconnected"
};

#ifdef PROC_DEBUG
static void lbs_debug_init(struct lbs_private *priv);
#endif

static ssize_t write_file_dummy(struct file *file, const char __user *buf,
                                size_t count, loff_t *ppos)
{
        return -EINVAL;
}

static const size_t len = PAGE_SIZE;

static ssize_t lbs_dev_info(struct file *file, char __user *userbuf,
                                  size_t count, loff_t *ppos)
{
        struct lbs_private *priv = file->private_data;
        size_t pos = 0;
        unsigned long addr = get_zeroed_page(GFP_KERNEL);
        char *buf = (char *)addr;
        ssize_t res;
        if (!buf)
                return -ENOMEM;

        pos += snprintf(buf+pos, len-pos, "state = %s\n",
                                szStates[priv->connect_status]);
        pos += snprintf(buf+pos, len-pos, "region_code = %02x\n",
                                (u32) priv->regioncode);

        res = simple_read_from_buffer(userbuf, count, ppos, buf, pos);

        free_page(addr);
        return res;
}

static ssize_t lbs_sleepparams_write(struct file *file,
                                const char __user *user_buf, size_t count,
                                loff_t *ppos)
{
        struct lbs_private *priv = file->private_data;
        ssize_t ret;
        struct sleep_params sp;
        int p1, p2, p3, p4, p5, p6;
        char *buf;

        buf = memdup_user_nul(user_buf, min(count, len - 1));
        if (IS_ERR(buf))
                return PTR_ERR(buf);

        ret = sscanf(buf, "%d %d %d %d %d %d", &p1, &p2, &p3, &p4, &p5, &p6);
        if (ret != 6) {
                ret = -EINVAL;
                goto out_unlock;
        }
        sp.sp_error = p1;
        sp.sp_offset = p2;
        sp.sp_stabletime = p3;
        sp.sp_calcontrol = p4;
        sp.sp_extsleepclk = p5;
        sp.sp_reserved = p6;

        ret = lbs_cmd_802_11_sleep_params(priv, CMD_ACT_SET, &sp);
        if (!ret)
                ret = count;
        else if (ret > 0)
                ret = -EINVAL;

out_unlock:
        kfree(buf);
        return ret;
}

static ssize_t lbs_sleepparams_read(struct file *file, char __user *userbuf,
                                  size_t count, loff_t *ppos)
{
        struct lbs_private *priv = file->private_data;
        ssize_t ret;
        size_t pos = 0;
        struct sleep_params sp;
        unsigned long addr = get_zeroed_page(GFP_KERNEL);
        char *buf = (char *)addr;
        if (!buf)
                return -ENOMEM;

        ret = lbs_cmd_802_11_sleep_params(priv, CMD_ACT_GET, &sp);
        if (ret)
                goto out_unlock;

        pos += snprintf(buf, len, "%d %d %d %d %d %d\n", sp.sp_error,
                        sp.sp_offset, sp.sp_stabletime,
                        sp.sp_calcontrol, sp.sp_extsleepclk,
                        sp.sp_reserved);

        ret = simple_read_from_buffer(userbuf, count, ppos, buf, pos);

out_unlock:
        free_page(addr);
        return ret;
}

static ssize_t lbs_host_sleep_write(struct file *file,
                                const char __user *user_buf, size_t count,
                                loff_t *ppos)
{
        struct lbs_private *priv = file->private_data;
        ssize_t ret;
        int host_sleep;
        char *buf;

        buf = memdup_user_nul(user_buf, min(count, len - 1));
        if (IS_ERR(buf))
                return PTR_ERR(buf);

        ret = sscanf(buf, "%d", &host_sleep);
        if (ret != 1) {
                ret = -EINVAL;
                goto out_unlock;
        }

        if (host_sleep == 0)
                ret = lbs_set_host_sleep(priv, 0);
        else if (host_sleep == 1) {
                if (priv->wol_criteria == EHS_REMOVE_WAKEUP) {
                        netdev_info(priv->dev,
                                    "wake parameters not configured\n");
                        ret = -EINVAL;
                        goto out_unlock;
                }
                ret = lbs_set_host_sleep(priv, 1);
        } else {
                netdev_err(priv->dev, "invalid option\n");
                ret = -EINVAL;
        }

        if (!ret)
                ret = count;

out_unlock:
        kfree(buf);
        return ret;
}

static ssize_t lbs_host_sleep_read(struct file *file, char __user *userbuf,
                                  size_t count, loff_t *ppos)
{
        struct lbs_private *priv = file->private_data;
        ssize_t ret;
        size_t pos = 0;
        unsigned long addr = get_zeroed_page(GFP_KERNEL);
        char *buf = (char *)addr;
        if (!buf)
                return -ENOMEM;

        pos += snprintf(buf, len, "%d\n", priv->is_host_sleep_activated);

        ret = simple_read_from_buffer(userbuf, count, ppos, buf, pos);

        free_page(addr);
        return ret;
}

/*
 * When calling CMD_802_11_SUBSCRIBE_EVENT with CMD_ACT_GET, me might
 * get a bunch of vendor-specific TLVs (a.k.a. IEs) back from the
 * firmware. Here's an example:
 *      04 01 02 00 00 00 05 01 02 00 00 00 06 01 02 00
 *      00 00 07 01 02 00 3c 00 00 00 00 00 00 00 03 03
 *      00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 *
 * The 04 01 is the TLV type (here TLV_TYPE_RSSI_LOW), 02 00 is the length,
 * 00 00 are the data bytes of this TLV. For this TLV, their meaning is
 * defined in mrvlietypes_thresholds
 *
 * This function searches in this TLV data chunk for a given TLV type
 * and returns a pointer to the first data byte of the TLV, or to NULL
 * if the TLV hasn't been found.
 */
static void *lbs_tlv_find(uint16_t tlv_type, const uint8_t *tlv, uint16_t size)
{
        struct mrvl_ie_header *tlv_h;
        uint16_t length;
        ssize_t pos = 0;

        while (pos < size) {
                tlv_h = (struct mrvl_ie_header *) tlv;
                if (!tlv_h->len)
                        return NULL;
                if (tlv_h->type == cpu_to_le16(tlv_type))
                        return tlv_h;
                length = le16_to_cpu(tlv_h->len) + sizeof(*tlv_h);
                pos += length;
                tlv += length;
        }
        return NULL;
}


static ssize_t lbs_threshold_read(uint16_t tlv_type, uint16_t event_mask,
                                  struct file *file, char __user *userbuf,
                                  size_t count, loff_t *ppos)
{
        struct cmd_ds_802_11_subscribe_event *subscribed;
        struct mrvl_ie_thresholds *got;
        struct lbs_private *priv = file->private_data;
        ssize_t ret = 0;
        size_t pos = 0;
        char *buf;
        u8 value;
        u8 freq;
        int events = 0;

        buf = (char *)get_zeroed_page(GFP_KERNEL);
        if (!buf)
                return -ENOMEM;

        subscribed = kzalloc_obj(*subscribed);
        if (!subscribed) {
                ret = -ENOMEM;
                goto out_page;
        }

        subscribed->hdr.size = cpu_to_le16(sizeof(*subscribed));
        subscribed->action = cpu_to_le16(CMD_ACT_GET);

        ret = lbs_cmd_with_response(priv, CMD_802_11_SUBSCRIBE_EVENT, subscribed);
        if (ret)
                goto out_cmd;

        got = lbs_tlv_find(tlv_type, subscribed->tlv, sizeof(subscribed->tlv));
        if (got) {
                value = got->value;
                freq  = got->freq;
                events = le16_to_cpu(subscribed->events);

                pos += snprintf(buf, len, "%d %d %d\n", value, freq,
                                !!(events & event_mask));
        }

        ret = simple_read_from_buffer(userbuf, count, ppos, buf, pos);

 out_cmd:
        kfree(subscribed);

 out_page:
        free_page((unsigned long)buf);
        return ret;
}


static ssize_t lbs_threshold_write(uint16_t tlv_type, uint16_t event_mask,
                                   struct file *file,
                                   const char __user *userbuf, size_t count,
                                   loff_t *ppos)
{
        struct cmd_ds_802_11_subscribe_event *events;
        struct mrvl_ie_thresholds *tlv;
        struct lbs_private *priv = file->private_data;
        int value, freq, new_mask;
        uint16_t curr_mask;
        char *buf;
        int ret;

        buf = memdup_user_nul(userbuf, min(count, len - 1));
        if (IS_ERR(buf))
                return PTR_ERR(buf);

        ret = sscanf(buf, "%d %d %d", &value, &freq, &new_mask);
        if (ret != 3) {
                ret = -EINVAL;
                goto out_page;
        }
        events = kzalloc_obj(*events);
        if (!events) {
                ret = -ENOMEM;
                goto out_page;
        }

        events->hdr.size = cpu_to_le16(sizeof(*events));
        events->action = cpu_to_le16(CMD_ACT_GET);

        ret = lbs_cmd_with_response(priv, CMD_802_11_SUBSCRIBE_EVENT, events);
        if (ret)
                goto out_events;

        curr_mask = le16_to_cpu(events->events);

        if (new_mask)
                new_mask = curr_mask | event_mask;
        else
                new_mask = curr_mask & ~event_mask;

        /* Now everything is set and we can send stuff down to the firmware */

        tlv = (void *)events->tlv;

        events->action = cpu_to_le16(CMD_ACT_SET);
        events->events = cpu_to_le16(new_mask);
        tlv->header.type = cpu_to_le16(tlv_type);
        tlv->header.len = cpu_to_le16(sizeof(*tlv) - sizeof(tlv->header));
        tlv->value = value;
        if (tlv_type != TLV_TYPE_BCNMISS)
                tlv->freq = freq;

        /* The command header, the action, the event mask, and one TLV */
        events->hdr.size = cpu_to_le16(sizeof(events->hdr) + 4 + sizeof(*tlv));

        ret = lbs_cmd_with_response(priv, CMD_802_11_SUBSCRIBE_EVENT, events);

        if (!ret)
                ret = count;
 out_events:
        kfree(events);
 out_page:
        kfree(buf);
        return ret;
}


static ssize_t lbs_lowrssi_read(struct file *file, char __user *userbuf,
                                size_t count, loff_t *ppos)
{
        return lbs_threshold_read(TLV_TYPE_RSSI_LOW, CMD_SUBSCRIBE_RSSI_LOW,
                                  file, userbuf, count, ppos);
}


static ssize_t lbs_lowrssi_write(struct file *file, const char __user *userbuf,
                                 size_t count, loff_t *ppos)
{
        return lbs_threshold_write(TLV_TYPE_RSSI_LOW, CMD_SUBSCRIBE_RSSI_LOW,
                                   file, userbuf, count, ppos);
}


static ssize_t lbs_lowsnr_read(struct file *file, char __user *userbuf,
                               size_t count, loff_t *ppos)
{
        return lbs_threshold_read(TLV_TYPE_SNR_LOW, CMD_SUBSCRIBE_SNR_LOW,
                                  file, userbuf, count, ppos);
}


static ssize_t lbs_lowsnr_write(struct file *file, const char __user *userbuf,
                                size_t count, loff_t *ppos)
{
        return lbs_threshold_write(TLV_TYPE_SNR_LOW, CMD_SUBSCRIBE_SNR_LOW,
                                   file, userbuf, count, ppos);
}


static ssize_t lbs_failcount_read(struct file *file, char __user *userbuf,
                                  size_t count, loff_t *ppos)
{
        return lbs_threshold_read(TLV_TYPE_FAILCOUNT, CMD_SUBSCRIBE_FAILCOUNT,
                                  file, userbuf, count, ppos);
}


static ssize_t lbs_failcount_write(struct file *file, const char __user *userbuf,
                                   size_t count, loff_t *ppos)
{
        return lbs_threshold_write(TLV_TYPE_FAILCOUNT, CMD_SUBSCRIBE_FAILCOUNT,
                                   file, userbuf, count, ppos);
}


static ssize_t lbs_highrssi_read(struct file *file, char __user *userbuf,
                                 size_t count, loff_t *ppos)
{
        return lbs_threshold_read(TLV_TYPE_RSSI_HIGH, CMD_SUBSCRIBE_RSSI_HIGH,
                                  file, userbuf, count, ppos);
}


static ssize_t lbs_highrssi_write(struct file *file, const char __user *userbuf,
                                  size_t count, loff_t *ppos)
{
        return lbs_threshold_write(TLV_TYPE_RSSI_HIGH, CMD_SUBSCRIBE_RSSI_HIGH,
                                   file, userbuf, count, ppos);
}


static ssize_t lbs_highsnr_read(struct file *file, char __user *userbuf,
                                size_t count, loff_t *ppos)
{
        return lbs_threshold_read(TLV_TYPE_SNR_HIGH, CMD_SUBSCRIBE_SNR_HIGH,
                                  file, userbuf, count, ppos);
}


static ssize_t lbs_highsnr_write(struct file *file, const char __user *userbuf,
                                 size_t count, loff_t *ppos)
{
        return lbs_threshold_write(TLV_TYPE_SNR_HIGH, CMD_SUBSCRIBE_SNR_HIGH,
                                   file, userbuf, count, ppos);
}

static ssize_t lbs_bcnmiss_read(struct file *file, char __user *userbuf,
                                size_t count, loff_t *ppos)
{
        return lbs_threshold_read(TLV_TYPE_BCNMISS, CMD_SUBSCRIBE_BCNMISS,
                                  file, userbuf, count, ppos);
}


static ssize_t lbs_bcnmiss_write(struct file *file, const char __user *userbuf,
                                 size_t count, loff_t *ppos)
{
        return lbs_threshold_write(TLV_TYPE_BCNMISS, CMD_SUBSCRIBE_BCNMISS,
                                   file, userbuf, count, ppos);
}


static ssize_t lbs_rdmac_read(struct file *file, char __user *userbuf,
                                  size_t count, loff_t *ppos)
{
        struct lbs_private *priv = file->private_data;
        ssize_t pos = 0;
        int ret;
        unsigned long addr = get_zeroed_page(GFP_KERNEL);
        char *buf = (char *)addr;
        u32 val = 0;

        if (!buf)
                return -ENOMEM;

        ret = lbs_get_reg(priv, CMD_MAC_REG_ACCESS, priv->mac_offset, &val);
        mdelay(10);
        if (!ret) {
                pos = snprintf(buf, len, "MAC[0x%x] = 0x%08x\n",
                                priv->mac_offset, val);
                ret = simple_read_from_buffer(userbuf, count, ppos, buf, pos);
        }
        free_page(addr);
        return ret;
}

static ssize_t lbs_rdmac_write(struct file *file,
                                    const char __user *userbuf,
                                    size_t count, loff_t *ppos)
{
        struct lbs_private *priv = file->private_data;
        char *buf;

        buf = memdup_user_nul(userbuf, min(count, len - 1));
        if (IS_ERR(buf))
                return PTR_ERR(buf);

        priv->mac_offset = simple_strtoul(buf, NULL, 16);
        kfree(buf);
        return count;
}

static ssize_t lbs_wrmac_write(struct file *file,
                                    const char __user *userbuf,
                                    size_t count, loff_t *ppos)
{

        struct lbs_private *priv = file->private_data;
        ssize_t res;
        u32 offset, value;
        char *buf;

        buf = memdup_user_nul(userbuf, min(count, len - 1));
        if (IS_ERR(buf))
                return PTR_ERR(buf);

        res = sscanf(buf, "%x %x", &offset, &value);
        if (res != 2) {
                res = -EFAULT;
                goto out_unlock;
        }

        res = lbs_set_reg(priv, CMD_MAC_REG_ACCESS, offset, value);
        mdelay(10);

        if (!res)
                res = count;
out_unlock:
        kfree(buf);
        return res;
}

static ssize_t lbs_rdbbp_read(struct file *file, char __user *userbuf,
                                  size_t count, loff_t *ppos)
{
        struct lbs_private *priv = file->private_data;
        ssize_t pos = 0;
        int ret;
        unsigned long addr = get_zeroed_page(GFP_KERNEL);
        char *buf = (char *)addr;
        u32 val;

        if (!buf)
                return -ENOMEM;

        ret = lbs_get_reg(priv, CMD_BBP_REG_ACCESS, priv->bbp_offset, &val);
        mdelay(10);
        if (!ret) {
                pos = snprintf(buf, len, "BBP[0x%x] = 0x%08x\n",
                                priv->bbp_offset, val);
                ret = simple_read_from_buffer(userbuf, count, ppos, buf, pos);
        }
        free_page(addr);

        return ret;
}

static ssize_t lbs_rdbbp_write(struct file *file,
                                    const char __user *userbuf,
                                    size_t count, loff_t *ppos)
{
        struct lbs_private *priv = file->private_data;
        char *buf;

        buf = memdup_user_nul(userbuf, min(count, len - 1));
        if (IS_ERR(buf))
                return PTR_ERR(buf);

        priv->bbp_offset = simple_strtoul(buf, NULL, 16);
        kfree(buf);

        return count;
}

static ssize_t lbs_wrbbp_write(struct file *file,
                                    const char __user *userbuf,
                                    size_t count, loff_t *ppos)
{

        struct lbs_private *priv = file->private_data;
        ssize_t res;
        u32 offset, value;
        char *buf;

        buf = memdup_user_nul(userbuf, min(count, len - 1));
        if (IS_ERR(buf))
                return PTR_ERR(buf);

        res = sscanf(buf, "%x %x", &offset, &value);
        if (res != 2) {
                res = -EFAULT;
                goto out_unlock;
        }

        res = lbs_set_reg(priv, CMD_BBP_REG_ACCESS, offset, value);
        mdelay(10);

        if (!res)
                res = count;
out_unlock:
        kfree(buf);
        return res;
}

static ssize_t lbs_rdrf_read(struct file *file, char __user *userbuf,
                                  size_t count, loff_t *ppos)
{
        struct lbs_private *priv = file->private_data;
        ssize_t pos = 0;
        int ret;
        unsigned long addr = get_zeroed_page(GFP_KERNEL);
        char *buf = (char *)addr;
        u32 val;

        if (!buf)
                return -ENOMEM;

        ret = lbs_get_reg(priv, CMD_RF_REG_ACCESS, priv->rf_offset, &val);
        mdelay(10);
        if (!ret) {
                pos = snprintf(buf, len, "RF[0x%x] = 0x%08x\n",
                                priv->rf_offset, val);
                ret = simple_read_from_buffer(userbuf, count, ppos, buf, pos);
        }
        free_page(addr);

        return ret;
}

static ssize_t lbs_rdrf_write(struct file *file,
                                    const char __user *userbuf,
                                    size_t count, loff_t *ppos)
{
        struct lbs_private *priv = file->private_data;
        char *buf;

        buf = memdup_user_nul(userbuf, min(count, len - 1));
        if (IS_ERR(buf))
                return PTR_ERR(buf);

        priv->rf_offset = simple_strtoul(buf, NULL, 16);
        kfree(buf);
        return count;
}

static ssize_t lbs_wrrf_write(struct file *file,
                                    const char __user *userbuf,
                                    size_t count, loff_t *ppos)
{

        struct lbs_private *priv = file->private_data;
        ssize_t res;
        u32 offset, value;
        char *buf;

        buf = memdup_user_nul(userbuf, min(count, len - 1));
        if (IS_ERR(buf))
                return PTR_ERR(buf);

        res = sscanf(buf, "%x %x", &offset, &value);
        if (res != 2) {
                res = -EFAULT;
                goto out_unlock;
        }

        res = lbs_set_reg(priv, CMD_RF_REG_ACCESS, offset, value);
        mdelay(10);

        if (!res)
                res = count;
out_unlock:
        kfree(buf);
        return res;
}

#define FOPS(fread, fwrite) { \
        .owner = THIS_MODULE, \
        .open = simple_open, \
        .read = (fread), \
        .write = (fwrite), \
        .llseek = generic_file_llseek, \
}

struct lbs_debugfs_files {
        const char *name;
        umode_t perm;
        struct file_operations fops;
};

static const struct lbs_debugfs_files debugfs_files[] = {
        { "info", 0444, FOPS(lbs_dev_info, write_file_dummy), },
        { "sleepparams", 0644, FOPS(lbs_sleepparams_read,
                                lbs_sleepparams_write), },
        { "hostsleep", 0644, FOPS(lbs_host_sleep_read,
                                lbs_host_sleep_write), },
};

static const struct lbs_debugfs_files debugfs_events_files[] = {
        {"low_rssi", 0644, FOPS(lbs_lowrssi_read,
                                lbs_lowrssi_write), },
        {"low_snr", 0644, FOPS(lbs_lowsnr_read,
                                lbs_lowsnr_write), },
        {"failure_count", 0644, FOPS(lbs_failcount_read,
                                lbs_failcount_write), },
        {"beacon_missed", 0644, FOPS(lbs_bcnmiss_read,
                                lbs_bcnmiss_write), },
        {"high_rssi", 0644, FOPS(lbs_highrssi_read,
                                lbs_highrssi_write), },
        {"high_snr", 0644, FOPS(lbs_highsnr_read,
                                lbs_highsnr_write), },
};

static const struct lbs_debugfs_files debugfs_regs_files[] = {
        {"rdmac", 0644, FOPS(lbs_rdmac_read, lbs_rdmac_write), },
        {"wrmac", 0600, FOPS(NULL, lbs_wrmac_write), },
        {"rdbbp", 0644, FOPS(lbs_rdbbp_read, lbs_rdbbp_write), },
        {"wrbbp", 0600, FOPS(NULL, lbs_wrbbp_write), },
        {"rdrf", 0644, FOPS(lbs_rdrf_read, lbs_rdrf_write), },
        {"wrrf", 0600, FOPS(NULL, lbs_wrrf_write), },
};

void lbs_debugfs_init(void)
{
        if (!lbs_dir)
                lbs_dir = debugfs_create_dir("lbs_wireless", NULL);
}

void lbs_debugfs_remove(void)
{
        debugfs_remove(lbs_dir);
}

void lbs_debugfs_init_one(struct lbs_private *priv, struct net_device *dev)
{
        int i;
        const struct lbs_debugfs_files *files;
        if (!lbs_dir)
                goto exit;

        priv->debugfs_dir = debugfs_create_dir(dev->name, lbs_dir);

        for (i=0; i<ARRAY_SIZE(debugfs_files); i++) {
                files = &debugfs_files[i];
                priv->debugfs_files[i] = debugfs_create_file(files->name,
                                                             files->perm,
                                                             priv->debugfs_dir,
                                                             priv,
                                                             &files->fops);
        }

        priv->events_dir = debugfs_create_dir("subscribed_events", priv->debugfs_dir);

        for (i=0; i<ARRAY_SIZE(debugfs_events_files); i++) {
                files = &debugfs_events_files[i];
                priv->debugfs_events_files[i] = debugfs_create_file(files->name,
                                                             files->perm,
                                                             priv->events_dir,
                                                             priv,
                                                             &files->fops);
        }

        priv->regs_dir = debugfs_create_dir("registers", priv->debugfs_dir);

        for (i=0; i<ARRAY_SIZE(debugfs_regs_files); i++) {
                files = &debugfs_regs_files[i];
                priv->debugfs_regs_files[i] = debugfs_create_file(files->name,
                                                             files->perm,
                                                             priv->regs_dir,
                                                             priv,
                                                             &files->fops);
        }

#ifdef PROC_DEBUG
        lbs_debug_init(priv);
#endif
exit:
        return;
}

void lbs_debugfs_remove_one(struct lbs_private *priv)
{
        int i;

        for(i=0; i<ARRAY_SIZE(debugfs_regs_files); i++)
                debugfs_remove(priv->debugfs_regs_files[i]);

        debugfs_remove(priv->regs_dir);

        for(i=0; i<ARRAY_SIZE(debugfs_events_files); i++)
                debugfs_remove(priv->debugfs_events_files[i]);

        debugfs_remove(priv->events_dir);
#ifdef PROC_DEBUG
        debugfs_remove(priv->debugfs_debug);
#endif
        for(i=0; i<ARRAY_SIZE(debugfs_files); i++)
                debugfs_remove(priv->debugfs_files[i]);
        debugfs_remove(priv->debugfs_dir);
}



/* debug entry */

#ifdef PROC_DEBUG

#define item_size(n)    (sizeof_field(struct lbs_private, n))
#define item_addr(n)    (offsetof(struct lbs_private, n))


struct debug_data {
        char name[32];
        u32 size;
        size_t addr;
};

/* To debug any member of struct lbs_private, simply add one line here.
 */
static struct debug_data items[] = {
        {"psmode", item_size(psmode), item_addr(psmode)},
        {"psstate", item_size(psstate), item_addr(psstate)},
};

static int num_of_items = ARRAY_SIZE(items);

/**
 * lbs_debugfs_read - proc read function
 *
 * @file:       file to read
 * @userbuf:    pointer to buffer
 * @count:      number of bytes to read
 * @ppos:       read data starting position
 *
 * returns:     amount of data read or negative error code
 */
static ssize_t lbs_debugfs_read(struct file *file, char __user *userbuf,
                        size_t count, loff_t *ppos)
{
        int val = 0;
        size_t pos = 0;
        ssize_t res;
        char *p;
        int i;
        struct debug_data *d;
        unsigned long addr = get_zeroed_page(GFP_KERNEL);
        char *buf = (char *)addr;
        if (!buf)
                return -ENOMEM;

        p = buf;

        d = file->private_data;

        for (i = 0; i < num_of_items; i++) {
                if (d[i].size == 1)
                        val = *((u8 *) d[i].addr);
                else if (d[i].size == 2)
                        val = *((u16 *) d[i].addr);
                else if (d[i].size == 4)
                        val = *((u32 *) d[i].addr);
                else if (d[i].size == 8)
                        val = *((u64 *) d[i].addr);

                pos += sprintf(p + pos, "%s=%d\n", d[i].name, val);
        }

        res = simple_read_from_buffer(userbuf, count, ppos, p, pos);

        free_page(addr);
        return res;
}

/**
 * lbs_debugfs_write - proc write function
 *
 * @f:          file pointer
 * @buf:        pointer to data buffer
 * @cnt:        data number to write
 * @ppos:       file position
 *
 * returns:     amount of data written
 */
static ssize_t lbs_debugfs_write(struct file *f, const char __user *buf,
                            size_t cnt, loff_t *ppos)
{
        int r, i;
        char *pdata;
        char *p;
        char *p0;
        char *p1;
        char *p2;
        struct debug_data *d = f->private_data;

        if (cnt == 0)
                return 0;

        pdata = memdup_user_nul(buf, cnt);
        if (IS_ERR(pdata))
                return PTR_ERR(pdata);

        p0 = pdata;
        for (i = 0; i < num_of_items; i++) {
                do {
                        p = strstr(p0, d[i].name);
                        if (p == NULL)
                                break;
                        p1 = strchr(p, '\n');
                        if (p1 == NULL)
                                break;
                        p0 = p1++;
                        p2 = strchr(p, '=');
                        if (!p2)
                                break;
                        p2++;
                        r = simple_strtoul(p2, NULL, 0);
                        if (d[i].size == 1)
                                *((u8 *) d[i].addr) = (u8) r;
                        else if (d[i].size == 2)
                                *((u16 *) d[i].addr) = (u16) r;
                        else if (d[i].size == 4)
                                *((u32 *) d[i].addr) = (u32) r;
                        else if (d[i].size == 8)
                                *((u64 *) d[i].addr) = (u64) r;
                        break;
                } while (1);
        }
        kfree(pdata);

        return (ssize_t)cnt;
}

static const struct file_operations lbs_debug_fops = {
        .owner = THIS_MODULE,
        .open = simple_open,
        .write = lbs_debugfs_write,
        .read = lbs_debugfs_read,
        .llseek = default_llseek,
};

/**
 * lbs_debug_init - create debug proc file
 *
 * @priv:       pointer to &struct lbs_private
 *
 * returns:     N/A
 */
static void lbs_debug_init(struct lbs_private *priv)
{
        int i;

        if (!priv->debugfs_dir)
                return;

        for (i = 0; i < num_of_items; i++)
                items[i].addr += (size_t) priv;

        priv->debugfs_debug = debugfs_create_file("debug", 0644,
                                                  priv->debugfs_dir, &items[0],
                                                  &lbs_debug_fops);
}
#endif