/*
 * Copyright (C) ST-Ericsson SA 2010
 *
 * Author: Mattias Wallin <mattias.wallin@stericsson.com> for ST-Ericsson.
 * License Terms: GNU General Public License v2
 */

#include <linux/seq_file.h>
#include <linux/uaccess.h>
#include <linux/fs.h>
#include <linux/debugfs.h>
#include <linux/platform_device.h>

#include <linux/mfd/abx500.h>
#include <linux/mfd/ab8500.h>

static u32 debug_bank;
static u32 debug_address;

/**
 * struct ab8500_reg_range
 * @first: the first address of the range
 * @last: the last address of the range
 * @perm: access permissions for the range
 */
struct ab8500_reg_range {
       u8 first;
       u8 last;
       u8 perm;
};

/**
 * struct ab8500_i2c_ranges
 * @num_ranges: the number of ranges in the list
 * @bankid: bank identifier
 * @range: the list of register ranges
 */
struct ab8500_i2c_ranges {
       u8 num_ranges;
       u8 bankid;
       const struct ab8500_reg_range *range;
};

#define AB8500_NAME_STRING "ab8500"
#define AB8500_NUM_BANKS 22

#define AB8500_REV_REG 0x80

static struct ab8500_i2c_ranges debug_ranges[AB8500_NUM_BANKS] = {
       [0x0] = {
               .num_ranges = 0,
               .range = 0,
       },
       [AB8500_SYS_CTRL1_BLOCK] = {
               .num_ranges = 3,
               .range = (struct ab8500_reg_range[]) {
                       {
                               .first = 0x00,
                               .last = 0x02,
                       },
                       {
                               .first = 0x42,
                               .last = 0x42,
                       },
                       {
                               .first = 0x80,
                               .last = 0x81,
                       },
               },
       },
       [AB8500_SYS_CTRL2_BLOCK] = {
               .num_ranges = 4,
               .range = (struct ab8500_reg_range[]) {
                       {
                               .first = 0x00,
                               .last = 0x0D,
                       },
                       {
                               .first = 0x0F,
                               .last = 0x17,
                       },
                       {
                               .first = 0x30,
                               .last = 0x30,
                       },
                       {
                               .first = 0x32,
                               .last = 0x33,
                       },
               },
       },
       [AB8500_REGU_CTRL1] = {
               .num_ranges = 3,
               .range = (struct ab8500_reg_range[]) {
                       {
                               .first = 0x00,
                               .last = 0x00,
                       },
                       {
                               .first = 0x03,
                               .last = 0x10,
                       },
                       {
                               .first = 0x80,
                               .last = 0x84,
                       },
               },
       },
       [AB8500_REGU_CTRL2] = {
               .num_ranges = 5,
               .range = (struct ab8500_reg_range[]) {
                       {
                               .first = 0x00,
                               .last = 0x15,
                       },
                       {
                               .first = 0x17,
                               .last = 0x19,
                       },
                       {
                               .first = 0x1B,
                               .last = 0x1D,
                       },
                       {
                               .first = 0x1F,
                               .last = 0x22,
                       },
                       {
                               .first = 0x40,
                               .last = 0x44,
                       },
                       /* 0x80-0x8B is SIM registers and should
                        * not be accessed from here */
               },
       },
       [AB8500_USB] = {
               .num_ranges = 2,
               .range = (struct ab8500_reg_range[]) {
                       {
                               .first = 0x80,
                               .last = 0x83,
                       },
                       {
                               .first = 0x87,
                               .last = 0x8A,
                       },
               },
       },
       [AB8500_TVOUT] = {
               .num_ranges = 9,
               .range = (struct ab8500_reg_range[]) {
                       {
                               .first = 0x00,
                               .last = 0x12,
                       },
                       {
                               .first = 0x15,
                               .last = 0x17,
                       },
                       {
                               .first = 0x19,
                               .last = 0x21,
                       },
                       {
                               .first = 0x27,
                               .last = 0x2C,
                       },
                       {
                               .first = 0x41,
                               .last = 0x41,
                       },
                       {
                               .first = 0x45,
                               .last = 0x5B,
                       },
                       {
                               .first = 0x5D,
                               .last = 0x5D,
                       },
                       {
                               .first = 0x69,
                               .last = 0x69,
                       },
                       {
                               .first = 0x80,
                               .last = 0x81,
                       },
               },
       },
       [AB8500_DBI] = {
               .num_ranges = 0,
               .range = 0,
       },
       [AB8500_ECI_AV_ACC] = {
               .num_ranges = 1,
               .range = (struct ab8500_reg_range[]) {
                       {
                               .first = 0x80,
                               .last = 0x82,
                       },
               },
       },
       [0x9] = {
               .num_ranges = 0,
               .range = 0,
       },
       [AB8500_GPADC] = {
               .num_ranges = 1,
               .range = (struct ab8500_reg_range[]) {
                       {
                               .first = 0x00,
                               .last = 0x08,
                       },
               },
       },
       [AB8500_CHARGER] = {
               .num_ranges = 8,
               .range = (struct ab8500_reg_range[]) {
                       {
                               .first = 0x00,
                               .last = 0x03,
                       },
                       {
                               .first = 0x05,
                               .last = 0x05,
                       },
                       {
                               .first = 0x40,
                               .last = 0x40,
                       },
                       {
                               .first = 0x42,
                               .last = 0x42,
                       },
                       {
                               .first = 0x44,
                               .last = 0x44,
                       },
                       {
                               .first = 0x50,
                               .last = 0x55,
                       },
                       {
                               .first = 0x80,
                               .last = 0x82,
                       },
                       {
                               .first = 0xC0,
                               .last = 0xC2,
                       },
               },
       },
       [AB8500_GAS_GAUGE] = {
               .num_ranges = 3,
               .range = (struct ab8500_reg_range[]) {
                       {
                               .first = 0x00,
                               .last = 0x00,
                       },
                       {
                               .first = 0x07,
                               .last = 0x0A,
                       },
                       {
                               .first = 0x10,
                               .last = 0x14,
                       },
               },
       },
       [AB8500_AUDIO] = {
               .num_ranges = 1,
               .range = (struct ab8500_reg_range[]) {
                       {
                               .first = 0x00,
                               .last = 0x6F,
                       },
               },
       },
       [AB8500_INTERRUPT] = {
               .num_ranges = 0,
               .range = 0,
       },
       [AB8500_RTC] = {
               .num_ranges = 1,
               .range = (struct ab8500_reg_range[]) {
                       {
                               .first = 0x00,
                               .last = 0x0F,
                       },
               },
       },
       [AB8500_MISC] = {
               .num_ranges = 8,
               .range = (struct ab8500_reg_range[]) {
                       {
                               .first = 0x00,
                               .last = 0x05,
                       },
                       {
                               .first = 0x10,
                               .last = 0x15,
                       },
                       {
                               .first = 0x20,
                               .last = 0x25,
                       },
                       {
                               .first = 0x30,
                               .last = 0x35,
                       },
                       {
                               .first = 0x40,
                               .last = 0x45,
                       },
                       {
                               .first = 0x50,
                               .last = 0x50,
                       },
                       {
                               .first = 0x60,
                               .last = 0x67,
                       },
                       {
                               .first = 0x80,
                               .last = 0x80,
                       },
               },
       },
       [0x11] = {
               .num_ranges = 0,
               .range = 0,
       },
       [0x12] = {
               .num_ranges = 0,
               .range = 0,
       },
       [0x13] = {
               .num_ranges = 0,
               .range = 0,
       },
       [0x14] = {
               .num_ranges = 0,
               .range = 0,
       },
       [AB8500_OTP_EMUL] = {
               .num_ranges = 1,
               .range = (struct ab8500_reg_range[]) {
                       {
                               .first = 0x01,
                               .last = 0x0F,
                       },
               },
       },
};

static int ab8500_registers_print(struct seq_file *s, void *p)
{
       struct device *dev = s->private;
       unsigned int i;
       u32 bank = debug_bank;

       seq_printf(s, AB8500_NAME_STRING " register values:\n");

       seq_printf(s, " bank %u:\n", bank);
       for (i = 0; i < debug_ranges[bank].num_ranges; i++) {
               u32 reg;

               for (reg = debug_ranges[bank].range[i].first;
                       reg <= debug_ranges[bank].range[i].last;
                       reg++) {
                       u8 value;
                       int err;

                       err = abx500_get_register_interruptible(dev,
                               (u8)bank, (u8)reg, &value);
                       if (err < 0) {
                               dev_err(dev, "ab->read fail %d\n", err);
                               return err;
                       }

                       err = seq_printf(s, "  [%u/0x%02X]: 0x%02X\n", bank,
                               reg, value);
                       if (err < 0) {
                               dev_err(dev, "seq_printf overflow\n");
                               /* Error is not returned here since
                                * the output is wanted in any case */
                               return 0;
                       }
               }
       }
       return 0;
}

static int ab8500_registers_open(struct inode *inode, struct file *file)
{
       return single_open(file, ab8500_registers_print, inode->i_private);
}

static const struct file_operations ab8500_registers_fops = {
       .open = ab8500_registers_open,
       .read = seq_read,
       .llseek = seq_lseek,
       .release = single_release,
       .owner = THIS_MODULE,
};

static int ab8500_bank_print(struct seq_file *s, void *p)
{
       return seq_printf(s, "%d\n", debug_bank);
}

static int ab8500_bank_open(struct inode *inode, struct file *file)
{
       return single_open(file, ab8500_bank_print, inode->i_private);
}

static ssize_t ab8500_bank_write(struct file *file,
       const char __user *user_buf,
       size_t count, loff_t *ppos)
{
       struct device *dev = ((struct seq_file *)(file->private_data))->private;
       char buf[32];
       int buf_size;
       unsigned long user_bank;
       int err;

       /* Get userspace string and assure termination */
       buf_size = min(count, (sizeof(buf) - 1));
       if (copy_from_user(buf, user_buf, buf_size))
               return -EFAULT;
       buf[buf_size] = 0;

       err = strict_strtoul(buf, 0, &user_bank);
       if (err)
               return -EINVAL;

       if (user_bank >= AB8500_NUM_BANKS) {
               dev_err(dev, "debugfs error input > number of banks\n");
               return -EINVAL;
       }

       debug_bank = user_bank;

       return buf_size;
}

static int ab8500_address_print(struct seq_file *s, void *p)
{
       return seq_printf(s, "0x%02X\n", debug_address);
}

static int ab8500_address_open(struct inode *inode, struct file *file)
{
       return single_open(file, ab8500_address_print, inode->i_private);
}

static ssize_t ab8500_address_write(struct file *file,
       const char __user *user_buf,
       size_t count, loff_t *ppos)
{
       struct device *dev = ((struct seq_file *)(file->private_data))->private;
       char buf[32];
       int buf_size;
       unsigned long user_address;
       int err;

       /* Get userspace string and assure termination */
       buf_size = min(count, (sizeof(buf) - 1));
       if (copy_from_user(buf, user_buf, buf_size))
               return -EFAULT;
       buf[buf_size] = 0;

       err = strict_strtoul(buf, 0, &user_address);
       if (err)
               return -EINVAL;
       if (user_address > 0xff) {
               dev_err(dev, "debugfs error input > 0xff\n");
               return -EINVAL;
       }
       debug_address = user_address;
       return buf_size;
}

static int ab8500_val_print(struct seq_file *s, void *p)
{
       struct device *dev = s->private;
       int ret;
       u8 regvalue;

       ret = abx500_get_register_interruptible(dev,
               (u8)debug_bank, (u8)debug_address, &regvalue);
       if (ret < 0) {
               dev_err(dev, "abx500_get_reg fail %d, %d\n",
                       ret, __LINE__);
               return -EINVAL;
       }
       seq_printf(s, "0x%02X\n", regvalue);

       return 0;
}

static int ab8500_val_open(struct inode *inode, struct file *file)
{
       return single_open(file, ab8500_val_print, inode->i_private);
}

static ssize_t ab8500_val_write(struct file *file,
       const char __user *user_buf,
       size_t count, loff_t *ppos)
{
       struct device *dev = ((struct seq_file *)(file->private_data))->private;
       char buf[32];
       int buf_size;
       unsigned long user_val;
       int err;

       /* Get userspace string and assure termination */
       buf_size = min(count, (sizeof(buf)-1));
       if (copy_from_user(buf, user_buf, buf_size))
               return -EFAULT;
       buf[buf_size] = 0;

       err = strict_strtoul(buf, 0, &user_val);
       if (err)
               return -EINVAL;
       if (user_val > 0xff) {
               dev_err(dev, "debugfs error input > 0xff\n");
               return -EINVAL;
       }
       err = abx500_set_register_interruptible(dev,
               (u8)debug_bank, debug_address, (u8)user_val);
       if (err < 0) {
               printk(KERN_ERR "abx500_set_reg failed %d, %d", err, __LINE__);
               return -EINVAL;
       }

       return buf_size;
}

static const struct file_operations ab8500_bank_fops = {
       .open = ab8500_bank_open,
       .write = ab8500_bank_write,
       .read = seq_read,
       .llseek = seq_lseek,
       .release = single_release,
       .owner = THIS_MODULE,
};

static const struct file_operations ab8500_address_fops = {
       .open = ab8500_address_open,
       .write = ab8500_address_write,
       .read = seq_read,
       .llseek = seq_lseek,
       .release = single_release,
       .owner = THIS_MODULE,
};

static const struct file_operations ab8500_val_fops = {
       .open = ab8500_val_open,
       .write = ab8500_val_write,
       .read = seq_read,
       .llseek = seq_lseek,
       .release = single_release,
       .owner = THIS_MODULE,
};

static struct dentry *ab8500_dir;
static struct dentry *ab8500_reg_file;
static struct dentry *ab8500_bank_file;
static struct dentry *ab8500_address_file;
static struct dentry *ab8500_val_file;

static int __devinit ab8500_debug_probe(struct platform_device *plf)
{
       debug_bank = AB8500_MISC;
       debug_address = AB8500_REV_REG & 0x00FF;

       ab8500_dir = debugfs_create_dir(AB8500_NAME_STRING, NULL);
       if (!ab8500_dir)
               goto exit_no_debugfs;

       ab8500_reg_file = debugfs_create_file("all-bank-registers",
               S_IRUGO, ab8500_dir, &plf->dev, &ab8500_registers_fops);
       if (!ab8500_reg_file)
               goto exit_destroy_dir;

       ab8500_bank_file = debugfs_create_file("register-bank",
               (S_IRUGO | S_IWUGO), ab8500_dir, &plf->dev, &ab8500_bank_fops);
       if (!ab8500_bank_file)
               goto exit_destroy_reg;

       ab8500_address_file = debugfs_create_file("register-address",
               (S_IRUGO | S_IWUGO), ab8500_dir, &plf->dev,
               &ab8500_address_fops);
       if (!ab8500_address_file)
               goto exit_destroy_bank;

       ab8500_val_file = debugfs_create_file("register-value",
               (S_IRUGO | S_IWUGO), ab8500_dir, &plf->dev, &ab8500_val_fops);
       if (!ab8500_val_file)
               goto exit_destroy_address;

       return 0;

exit_destroy_address:
       debugfs_remove(ab8500_address_file);
exit_destroy_bank:
       debugfs_remove(ab8500_bank_file);
exit_destroy_reg:
       debugfs_remove(ab8500_reg_file);
exit_destroy_dir:
       debugfs_remove(ab8500_dir);
exit_no_debugfs:
       dev_err(&plf->dev, "failed to create debugfs entries.\n");
       return -ENOMEM;
}

static int __devexit ab8500_debug_remove(struct platform_device *plf)
{
       debugfs_remove(ab8500_val_file);
       debugfs_remove(ab8500_address_file);
       debugfs_remove(ab8500_bank_file);
       debugfs_remove(ab8500_reg_file);
       debugfs_remove(ab8500_dir);

       return 0;
}

static struct platform_driver ab8500_debug_driver = {
       .driver = {
               .name = "ab8500-debug",
               .owner = THIS_MODULE,
       },
       .probe  = ab8500_debug_probe,
       .remove = __devexit_p(ab8500_debug_remove)
};

static int __init ab8500_debug_init(void)
{
       return platform_driver_register(&ab8500_debug_driver);
}

static void __exit ab8500_debug_exit(void)
{
       platform_driver_unregister(&ab8500_debug_driver);
}
subsys_initcall(ab8500_debug_init);
module_exit(ab8500_debug_exit);

MODULE_AUTHOR("Mattias WALLIN <mattias.wallin@stericsson.com");
MODULE_DESCRIPTION("AB8500 DEBUG");
MODULE_LICENSE("GPL v2");