/******************************************************************************
 *
 * Copyright(c) 2003 - 2010 Intel Corporation. All rights reserved.
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of version 2 of the GNU General Public License as
 * published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
 * more details.
 *
 * You should have received a copy of the GNU General Public License along with
 * this program; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110, USA
 *
 * The full GNU General Public License is included in this distribution in the
 * file called LICENSE.
 *
 * Contact Information:
 *  Intel Linux Wireless <ilw@linux.intel.com>
 * Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
 *
 *****************************************************************************/


#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/pci.h>
#include <linux/dma-mapping.h>
#include <linux/delay.h>
#include <linux/skbuff.h>
#include <linux/netdevice.h>
#include <linux/wireless.h>
#include <net/mac80211.h>
#include <linux/etherdevice.h>
#include <asm/unaligned.h>

#include "iwl-dev.h"
#include "iwl-core.h"
#include "iwl-io.h"

/* default: IWL_LED_BLINK(0) using blinking index table */
static int led_mode;
module_param(led_mode, int, S_IRUGO);
MODULE_PARM_DESC(led_mode, "0=system default, "
                "1=On(RF On)/Off(RF Off), 2=blinking");

static const struct {
        u16 tpt;        /* Mb/s */
        u8 on_time;
        u8 off_time;
} blink_tbl[] =
{
        {300, 25, 25},
        {200, 40, 40},
        {100, 55, 55},
        {70, 65, 65},
        {50, 75, 75},
        {20, 85, 85},
        {10, 95, 95},
        {5, 110, 110},
        {1, 130, 130},
        {0, 167, 167},
        /* SOLID_ON */
        {-1, IWL_LED_SOLID, 0}
};

#define IWL_1MB_RATE (128 * 1024)
#define IWL_LED_THRESHOLD (16)
#define IWL_MAX_BLINK_TBL (ARRAY_SIZE(blink_tbl) - 1) /* exclude SOLID_ON */
#define IWL_SOLID_BLINK_IDX (ARRAY_SIZE(blink_tbl) - 1)

/*
 * Adjust led blink rate to compensate on a MAC Clock difference on every HW
 * Led blink rate analysis showed an average deviation of 0% on 3945,
 * 5% on 4965 HW and 20% on 5000 series and up.
 * Need to compensate on the led on/off time per HW according to the deviation
 * to achieve the desired led frequency
 * The calculation is: (100-averageDeviation)/100 * blinkTime
 * For code efficiency the calculation will be:
 *     compensation = (100 - averageDeviation) * 64 / 100
 *     NewBlinkTime = (compensation * BlinkTime) / 64
 */
static inline u8 iwl_blink_compensation(struct iwl_priv *priv,
                                    u8 time, u16 compensation)
{
        if (!compensation) {
                IWL_ERR(priv, "undefined blink compensation: "
                        "use pre-defined blinking time\n");
                return time;
        }

        return (u8)((time * compensation) >> 6);
}

/* Set led pattern command */
static int iwl_led_pattern(struct iwl_priv *priv, unsigned int idx)
{
        struct iwl_led_cmd led_cmd = {
                .id = IWL_LED_LINK,
                .interval = IWL_DEF_LED_INTRVL
        };

        BUG_ON(idx > IWL_MAX_BLINK_TBL);

        IWL_DEBUG_LED(priv, "Led blink time compensation= %u\n",
                        priv->cfg->base_params->led_compensation);
        led_cmd.on =
                iwl_blink_compensation(priv, blink_tbl[idx].on_time,
                                priv->cfg->base_params->led_compensation);
        led_cmd.off =
                iwl_blink_compensation(priv, blink_tbl[idx].off_time,
                                priv->cfg->base_params->led_compensation);

        return priv->cfg->ops->led->cmd(priv, &led_cmd);
}

int iwl_led_start(struct iwl_priv *priv)
{
        return priv->cfg->ops->led->on(priv);
}
EXPORT_SYMBOL(iwl_led_start);

int iwl_led_associate(struct iwl_priv *priv)
{
        IWL_DEBUG_LED(priv, "Associated\n");
        if (priv->cfg->led_mode == IWL_LED_BLINK)
                priv->allow_blinking = 1;
        priv->last_blink_time = jiffies;

        return 0;
}
EXPORT_SYMBOL(iwl_led_associate);

int iwl_led_disassociate(struct iwl_priv *priv)
{
        priv->allow_blinking = 0;

        return 0;
}
EXPORT_SYMBOL(iwl_led_disassociate);

/*
 * calculate blink rate according to last second Tx/Rx activities
 */
static int iwl_get_blink_rate(struct iwl_priv *priv)
{
        int i;
        /* count both tx and rx traffic to be able to
         * handle traffic in either direction
         */
        u64 current_tpt = priv->tx_stats.data_bytes +
                          priv->rx_stats.data_bytes;
        s64 tpt = current_tpt - priv->led_tpt;

        if (tpt < 0) /* wraparound */
                tpt = -tpt;

        IWL_DEBUG_LED(priv, "tpt %lld current_tpt %llu\n",
                (long long)tpt,
                (unsigned long long)current_tpt);
        priv->led_tpt = current_tpt;

        if (!priv->allow_blinking)
                i = IWL_MAX_BLINK_TBL;
        else
                for (i = 0; i < IWL_MAX_BLINK_TBL; i++)
                        if (tpt > (blink_tbl[i].tpt * IWL_1MB_RATE))
                                break;

        IWL_DEBUG_LED(priv, "LED BLINK IDX=%d\n", i);
        return i;
}

/*
 * this function called from handler. Since setting Led command can
 * happen very frequent we postpone led command to be called from
 * REPLY handler so we know ucode is up
 */
void iwl_leds_background(struct iwl_priv *priv)
{
        u8 blink_idx;

        if (test_bit(STATUS_EXIT_PENDING, &priv->status)) {
                priv->last_blink_time = 0;
                return;
        }
        if (iwl_is_rfkill(priv)) {
                priv->last_blink_time = 0;
                return;
        }

        if (!priv->allow_blinking) {
                priv->last_blink_time = 0;
                if (priv->last_blink_rate != IWL_SOLID_BLINK_IDX) {
                        priv->last_blink_rate = IWL_SOLID_BLINK_IDX;
                        iwl_led_pattern(priv, IWL_SOLID_BLINK_IDX);
                }
                return;
        }
        if (!priv->last_blink_time ||
            !time_after(jiffies, priv->last_blink_time +
                        msecs_to_jiffies(1000)))
                return;

        blink_idx = iwl_get_blink_rate(priv);

        /* call only if blink rate change */
        if (blink_idx != priv->last_blink_rate)
                iwl_led_pattern(priv, blink_idx);

        priv->last_blink_time = jiffies;
        priv->last_blink_rate = blink_idx;
}
EXPORT_SYMBOL(iwl_leds_background);

void iwl_leds_init(struct iwl_priv *priv)
{
        priv->last_blink_rate = 0;
        priv->last_blink_time = 0;
        priv->allow_blinking = 0;
        if (led_mode != IWL_LED_DEFAULT &&
            led_mode != priv->cfg->led_mode)
                priv->cfg->led_mode = led_mode;
}
EXPORT_SYMBOL(iwl_leds_init);