/**
 * Copyright (c) 2014 Redpine Signals Inc.
 *
 * Permission to use, copy, modify, and/or distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <linux/module.h>
#include <linux/firmware.h>
#include "rsi_mgmt.h"
#include "rsi_common.h"

u32 rsi_zone_enabled = /* INFO_ZONE |
                        INIT_ZONE |
                        MGMT_TX_ZONE |
                        MGMT_RX_ZONE |
                        DATA_TX_ZONE |
                        DATA_RX_ZONE |
                        FSM_ZONE |
                        ISR_ZONE | */
                        ERR_ZONE |
                        0;
EXPORT_SYMBOL_GPL(rsi_zone_enabled);

/**
 * rsi_dbg() - This function outputs informational messages.
 * @zone: Zone of interest for output message.
 * @fmt: printf-style format for output message.
 *
 * Return: none
 */
void rsi_dbg(u32 zone, const char *fmt, ...)
{
        struct va_format vaf;
        va_list args;

        va_start(args, fmt);

        vaf.fmt = fmt;
        vaf.va = &args;

        if (zone & rsi_zone_enabled)
                pr_info("%pV", &vaf);
        va_end(args);
}
EXPORT_SYMBOL_GPL(rsi_dbg);

/**
 * rsi_prepare_skb() - This function prepares the skb.
 * @common: Pointer to the driver private structure.
 * @buffer: Pointer to the packet data.
 * @pkt_len: Length of the packet.
 * @extended_desc: Extended descriptor.
 *
 * Return: Successfully skb.
 */
static struct sk_buff *rsi_prepare_skb(struct rsi_common *common,
                                       u8 *buffer,
                                       u32 pkt_len,
                                       u8 extended_desc)
{
        struct ieee80211_tx_info *info;
        struct skb_info *rx_params;
        struct sk_buff *skb = NULL;
        u8 payload_offset;

        if (WARN(!pkt_len, "%s: Dummy pkt received", __func__))
                return NULL;

        if (pkt_len > (RSI_RCV_BUFFER_LEN * 4)) {
                rsi_dbg(ERR_ZONE, "%s: Pkt size > max rx buf size %d\n",
                        __func__, pkt_len);
                pkt_len = RSI_RCV_BUFFER_LEN * 4;
        }

        pkt_len -= extended_desc;
        skb = dev_alloc_skb(pkt_len + FRAME_DESC_SZ);
        if (skb == NULL)
                return NULL;

        payload_offset = (extended_desc + FRAME_DESC_SZ);
        skb_put(skb, pkt_len);
        memcpy((skb->data), (buffer + payload_offset), skb->len);

        info = IEEE80211_SKB_CB(skb);
        rx_params = (struct skb_info *)info->driver_data;
        rx_params->rssi = rsi_get_rssi(buffer);
        rx_params->channel = rsi_get_connected_channel(common->priv);

        return skb;
}

/**
 * rsi_read_pkt() - This function reads frames from the card.
 * @common: Pointer to the driver private structure.
 * @rcv_pkt_len: Received pkt length. In case of USB it is 0.
 *
 * Return: 0 on success, -1 on failure.
 */
int rsi_read_pkt(struct rsi_common *common, s32 rcv_pkt_len)
{
        u8 *frame_desc = NULL, extended_desc = 0;
        u32 index, length = 0, queueno = 0;
        u16 actual_length = 0, offset;
        struct sk_buff *skb = NULL;

        index = 0;
        do {
                frame_desc = &common->rx_data_pkt[index];
                actual_length = *(u16 *)&frame_desc[0];
                offset = *(u16 *)&frame_desc[2];

                queueno = rsi_get_queueno(frame_desc, offset);
                length = rsi_get_length(frame_desc, offset);
                extended_desc = rsi_get_extended_desc(frame_desc, offset);

                switch (queueno) {
                case RSI_WIFI_DATA_Q:
                        skb = rsi_prepare_skb(common,
                                              (frame_desc + offset),
                                              length,
                                              extended_desc);
                        if (skb == NULL)
                                goto fail;

                        rsi_indicate_pkt_to_os(common, skb);
                        break;

                case RSI_WIFI_MGMT_Q:
                        rsi_mgmt_pkt_recv(common, (frame_desc + offset));
                        break;

                default:
                        rsi_dbg(ERR_ZONE, "%s: pkt from invalid queue: %d\n",
                                __func__,   queueno);
                        goto fail;
                }

                index  += actual_length;
                rcv_pkt_len -= actual_length;
        } while (rcv_pkt_len > 0);

        return 0;
fail:
        return -EINVAL;
}
EXPORT_SYMBOL_GPL(rsi_read_pkt);

/**
 * rsi_tx_scheduler_thread() - This function is a kernel thread to send the
 *                             packets to the device.
 * @common: Pointer to the driver private structure.
 *
 * Return: None.
 */
static void rsi_tx_scheduler_thread(struct rsi_common *common)
{
        struct rsi_hw *adapter = common->priv;
        u32 timeout = EVENT_WAIT_FOREVER;

        do {
                if (adapter->determine_event_timeout)
                        timeout = adapter->determine_event_timeout(adapter);
                rsi_wait_event(&common->tx_thread.event, timeout);
                rsi_reset_event(&common->tx_thread.event);

                if (common->init_done)
                        rsi_core_qos_processor(common);
        } while (atomic_read(&common->tx_thread.thread_done) == 0);
        complete_and_exit(&common->tx_thread.completion, 0);
}

/**
 * rsi_91x_init() - This function initializes os interface operations.
 * @void: Void.
 *
 * Return: Pointer to the adapter structure on success, NULL on failure .
 */
struct rsi_hw *rsi_91x_init(void)
{
        struct rsi_hw *adapter = NULL;
        struct rsi_common *common = NULL;
        u8 ii = 0;

        adapter = kzalloc(sizeof(*adapter), GFP_KERNEL);
        if (!adapter)
                return NULL;

        adapter->priv = kzalloc(sizeof(*common), GFP_KERNEL);
        if (adapter->priv == NULL) {
                rsi_dbg(ERR_ZONE, "%s: Failed in allocation of memory\n",
                        __func__);
                kfree(adapter);
                return NULL;
        } else {
                common = adapter->priv;
                common->priv = adapter;
        }

        for (ii = 0; ii < NUM_SOFT_QUEUES; ii++)
                skb_queue_head_init(&common->tx_queue[ii]);

        rsi_init_event(&common->tx_thread.event);
        mutex_init(&common->mutex);
        mutex_init(&common->tx_rxlock);

        if (rsi_create_kthread(common,
                               &common->tx_thread,
                               rsi_tx_scheduler_thread,
                               "Tx-Thread")) {
                rsi_dbg(ERR_ZONE, "%s: Unable to init tx thrd\n", __func__);
                goto err;
        }

        common->init_done = true;
        return adapter;

err:
        kfree(common);
        kfree(adapter);
        return NULL;
}
EXPORT_SYMBOL_GPL(rsi_91x_init);

/**
 * rsi_91x_deinit() - This function de-intializes os intf operations.
 * @adapter: Pointer to the adapter structure.
 *
 * Return: None.
 */
void rsi_91x_deinit(struct rsi_hw *adapter)
{
        struct rsi_common *common = adapter->priv;
        u8 ii;

        rsi_dbg(INFO_ZONE, "%s: Performing deinit os ops\n", __func__);

        rsi_kill_thread(&common->tx_thread);

        for (ii = 0; ii < NUM_SOFT_QUEUES; ii++)
                skb_queue_purge(&common->tx_queue[ii]);

        common->init_done = false;

        kfree(common);
        kfree(adapter->rsi_dev);
        kfree(adapter);
}
EXPORT_SYMBOL_GPL(rsi_91x_deinit);

/**
 * rsi_91x_hal_module_init() - This function is invoked when the module is
 *                             loaded into the kernel.
 *                             It registers the client driver.
 * @void: Void.
 *
 * Return: 0 on success, -1 on failure.
 */
static int rsi_91x_hal_module_init(void)
{
        rsi_dbg(INIT_ZONE, "%s: Module init called\n", __func__);
        return 0;
}

/**
 * rsi_91x_hal_module_exit() - This function is called at the time of
 *                             removing/unloading the module.
 *                             It unregisters the client driver.
 * @void: Void.
 *
 * Return: None.
 */
static void rsi_91x_hal_module_exit(void)
{
        rsi_dbg(INIT_ZONE, "%s: Module exit called\n", __func__);
}

module_init(rsi_91x_hal_module_init);
module_exit(rsi_91x_hal_module_exit);
MODULE_AUTHOR("Redpine Signals Inc");
MODULE_DESCRIPTION("Station driver for RSI 91x devices");
MODULE_SUPPORTED_DEVICE("RSI-91x");
MODULE_VERSION("0.1");
MODULE_LICENSE("Dual BSD/GPL");