/*
 * Copyright (C) ST-Ericsson SA 2010
 *
 * License Terms: GNU General Public License v2
 * Authors: Sundar Iyer <sundar.iyer@stericsson.com> for ST-Ericsson
 *          Bengt Jonsson <bengt.g.jonsson@stericsson.com> for ST-Ericsson
 *
 * UX500 common part of Power domain regulators
 */

#include <linux/kernel.h>
#include <linux/err.h>
#include <linux/regulator/driver.h>
#include <linux/debugfs.h>
#include <linux/seq_file.h>
#include <linux/slab.h>
#include <linux/module.h>

#include "dbx500-prcmu.h"

/*
 * power state reference count
 */
static int power_state_active_cnt; /* will initialize to zero */
static DEFINE_SPINLOCK(power_state_active_lock);

void power_state_active_enable(void)
{
        unsigned long flags;

        spin_lock_irqsave(&power_state_active_lock, flags);
        power_state_active_cnt++;
        spin_unlock_irqrestore(&power_state_active_lock, flags);
}

int power_state_active_disable(void)
{
        int ret = 0;
        unsigned long flags;

        spin_lock_irqsave(&power_state_active_lock, flags);
        if (power_state_active_cnt <= 0) {
                pr_err("power state: unbalanced enable/disable calls\n");
                ret = -EINVAL;
                goto out;
        }

        power_state_active_cnt--;
out:
        spin_unlock_irqrestore(&power_state_active_lock, flags);
        return ret;
}

#ifdef CONFIG_REGULATOR_DEBUG

static int power_state_active_get(void)
{
        unsigned long flags;
        int cnt;

        spin_lock_irqsave(&power_state_active_lock, flags);
        cnt = power_state_active_cnt;
        spin_unlock_irqrestore(&power_state_active_lock, flags);

        return cnt;
}

static struct ux500_regulator_debug {
        struct dentry *dir;
        struct dentry *status_file;
        struct dentry *power_state_cnt_file;
        struct dbx500_regulator_info *regulator_array;
        int num_regulators;
        u8 *state_before_suspend;
        u8 *state_after_suspend;
} rdebug;

void ux500_regulator_suspend_debug(void)
{
        int i;
        for (i = 0; i < rdebug.num_regulators; i++)
                rdebug.state_before_suspend[i] =
                        rdebug.regulator_array[i].is_enabled;
}

void ux500_regulator_resume_debug(void)
{
        int i;
        for (i = 0; i < rdebug.num_regulators; i++)
                rdebug.state_after_suspend[i] =
                        rdebug.regulator_array[i].is_enabled;
}

static int ux500_regulator_power_state_cnt_print(struct seq_file *s, void *p)
{
        struct device *dev = s->private;
        int err;

        /* print power state count */
        err = seq_printf(s, "ux500-regulator power state count: %i\n",
                power_state_active_get());
        if (err < 0)
                dev_err(dev, "seq_printf overflow\n");

        return 0;
}

static int ux500_regulator_power_state_cnt_open(struct inode *inode,
        struct file *file)
{
        return single_open(file, ux500_regulator_power_state_cnt_print,
                inode->i_private);
}

static const struct file_operations ux500_regulator_power_state_cnt_fops = {
        .open = ux500_regulator_power_state_cnt_open,
        .read = seq_read,
        .llseek = seq_lseek,
        .release = single_release,
        .owner = THIS_MODULE,
};

static int ux500_regulator_status_print(struct seq_file *s, void *p)
{
        struct device *dev = s->private;
        int err;
        int i;

        /* print dump header */
        err = seq_printf(s, "ux500-regulator status:\n");
        if (err < 0)
                dev_err(dev, "seq_printf overflow\n");

        err = seq_printf(s, "%31s : %8s : %8s\n", "current",
                "before", "after");
        if (err < 0)
                dev_err(dev, "seq_printf overflow\n");

        for (i = 0; i < rdebug.num_regulators; i++) {
                struct dbx500_regulator_info *info;
                /* Access per-regulator data */
                info = &rdebug.regulator_array[i];

                /* print status */
                err = seq_printf(s, "%20s : %8s : %8s : %8s\n", info->desc.name,
                        info->is_enabled ? "enabled" : "disabled",
                        rdebug.state_before_suspend[i] ? "enabled" : "disabled",
                        rdebug.state_after_suspend[i] ? "enabled" : "disabled");
                if (err < 0)
                        dev_err(dev, "seq_printf overflow\n");
        }

        return 0;
}

static int ux500_regulator_status_open(struct inode *inode, struct file *file)
{
        return single_open(file, ux500_regulator_status_print,
                inode->i_private);
}

static const struct file_operations ux500_regulator_status_fops = {
        .open = ux500_regulator_status_open,
        .read = seq_read,
        .llseek = seq_lseek,
        .release = single_release,
        .owner = THIS_MODULE,
};

int __attribute__((weak)) dbx500_regulator_testcase(
        struct dbx500_regulator_info *regulator_info,
        int num_regulators)
{
        return 0;
}

int
ux500_regulator_debug_init(struct platform_device *pdev,
        struct dbx500_regulator_info *regulator_info,
        int num_regulators)
{
        /* create directory */
        rdebug.dir = debugfs_create_dir("ux500-regulator", NULL);
        if (!rdebug.dir)
                goto exit_no_debugfs;

        /* create "status" file */
        rdebug.status_file = debugfs_create_file("status",
                S_IRUGO, rdebug.dir, &pdev->dev,
                &ux500_regulator_status_fops);
        if (!rdebug.status_file)
                goto exit_destroy_dir;

        /* create "power-state-count" file */
        rdebug.power_state_cnt_file = debugfs_create_file("power-state-count",
                S_IRUGO, rdebug.dir, &pdev->dev,
                &ux500_regulator_power_state_cnt_fops);
        if (!rdebug.power_state_cnt_file)
                goto exit_destroy_status;

        rdebug.regulator_array = regulator_info;
        rdebug.num_regulators = num_regulators;

        rdebug.state_before_suspend = kzalloc(num_regulators, GFP_KERNEL);
        if (!rdebug.state_before_suspend) {
                dev_err(&pdev->dev,
                        "could not allocate memory for saving state\n");
                goto exit_destroy_power_state;
        }

        rdebug.state_after_suspend = kzalloc(num_regulators, GFP_KERNEL);
        if (!rdebug.state_after_suspend) {
                dev_err(&pdev->dev,
                        "could not allocate memory for saving state\n");
                goto exit_free;
        }

        dbx500_regulator_testcase(regulator_info, num_regulators);
        return 0;

exit_free:
        kfree(rdebug.state_before_suspend);
exit_destroy_power_state:
        debugfs_remove(rdebug.power_state_cnt_file);
exit_destroy_status:
        debugfs_remove(rdebug.status_file);
exit_destroy_dir:
        debugfs_remove(rdebug.dir);
exit_no_debugfs:
        dev_err(&pdev->dev, "failed to create debugfs entries.\n");
        return -ENOMEM;
}

int ux500_regulator_debug_exit(void)
{
        debugfs_remove_recursive(rdebug.dir);
        kfree(rdebug.state_after_suspend);
        kfree(rdebug.state_before_suspend);

        return 0;
}
#endif