/*
 * 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.
 *
 */

#include <linux/firmware.h>
#include <net/rsi_91x.h>
#include "rsi_sdio.h"
#include "rsi_common.h"

/**
 * rsi_sdio_master_access_msword() - This function sets the AHB master access
 *                                   MS word in the SDIO slave registers.
 * @adapter: Pointer to the adapter structure.
 * @ms_word: ms word need to be initialized.
 *
 * Return: status: 0 on success, -1 on failure.
 */
int rsi_sdio_master_access_msword(struct rsi_hw *adapter, u16 ms_word)
{
        u8 byte;
        u8 function = 0;
        int status = 0;

        byte = (u8)(ms_word & 0x00FF);

        rsi_dbg(INIT_ZONE,
                "%s: MASTER_ACCESS_MSBYTE:0x%x\n", __func__, byte);

        status = rsi_sdio_write_register(adapter,
                                         function,
                                         SDIO_MASTER_ACCESS_MSBYTE,
                                         &byte);
        if (status) {
                rsi_dbg(ERR_ZONE,
                        "%s: fail to access MASTER_ACCESS_MSBYTE\n",
                        __func__);
                return -1;
        }

        byte = (u8)(ms_word >> 8);

        rsi_dbg(INIT_ZONE, "%s:MASTER_ACCESS_LSBYTE:0x%x\n", __func__, byte);
        status = rsi_sdio_write_register(adapter,
                                         function,
                                         SDIO_MASTER_ACCESS_LSBYTE,
                                         &byte);
        return status;
}

static void rsi_rx_handler(struct rsi_hw *adapter);

void rsi_sdio_rx_thread(struct rsi_common *common)
{
        struct rsi_hw *adapter = common->priv;
        struct rsi_91x_sdiodev *sdev = adapter->rsi_dev;

        do {
                rsi_wait_event(&sdev->rx_thread.event, EVENT_WAIT_FOREVER);
                rsi_reset_event(&sdev->rx_thread.event);
                rsi_rx_handler(adapter);
        } while (!atomic_read(&sdev->rx_thread.thread_done));

        rsi_dbg(INFO_ZONE, "%s: Terminated SDIO RX thread\n", __func__);
        atomic_inc(&sdev->rx_thread.thread_done);
        kthread_complete_and_exit(&sdev->rx_thread.completion, 0);
}

/**
 * rsi_process_pkt() - This Function reads rx_blocks register and figures out
 *                     the size of the rx pkt.
 * @common: Pointer to the driver private structure.
 *
 * Return: 0 on success, -1 on failure.
 */
static int rsi_process_pkt(struct rsi_common *common)
{
        struct rsi_hw *adapter = common->priv;
        struct rsi_91x_sdiodev *dev = adapter->rsi_dev;
        u8 num_blks = 0;
        u32 rcv_pkt_len = 0;
        int status = 0;
        u8 value = 0;

        num_blks = ((adapter->interrupt_status & 1) |
                        ((adapter->interrupt_status >> RECV_NUM_BLOCKS) << 1));

        if (!num_blks) {
                status = rsi_sdio_read_register(adapter,
                                                SDIO_RX_NUM_BLOCKS_REG,
                                                &value);
                if (status) {
                        rsi_dbg(ERR_ZONE,
                                "%s: Failed to read pkt length from the card:\n",
                                __func__);
                        return status;
                }
                num_blks = value & 0x1f;
        }

        if (dev->write_fail == 2)
                rsi_sdio_ack_intr(common->priv, (1 << MSDU_PKT_PENDING));

        if (unlikely(!num_blks)) {
                dev->write_fail = 2;
                return -1;
        }

        rcv_pkt_len = (num_blks * 256);

        status = rsi_sdio_host_intf_read_pkt(adapter, dev->pktbuffer,
                                             rcv_pkt_len);
        if (status) {
                rsi_dbg(ERR_ZONE, "%s: Failed to read packet from card\n",
                        __func__);
                return status;
        }

        status = rsi_read_pkt(common, dev->pktbuffer, rcv_pkt_len);
        if (status) {
                rsi_dbg(ERR_ZONE, "Failed to read the packet\n");
                return status;
        }

        return 0;
}

/**
 * rsi_init_sdio_slave_regs() - This function does the actual initialization
 *                              of SDBUS slave registers.
 * @adapter: Pointer to the adapter structure.
 *
 * Return: status: 0 on success, -1 on failure.
 */
int rsi_init_sdio_slave_regs(struct rsi_hw *adapter)
{
        struct rsi_91x_sdiodev *dev = adapter->rsi_dev;
        u8 function = 0;
        u8 byte;
        int status = 0;

        if (dev->next_read_delay) {
                byte = dev->next_read_delay;
                status = rsi_sdio_write_register(adapter,
                                                 function,
                                                 SDIO_NXT_RD_DELAY2,
                                                 &byte);
                if (status) {
                        rsi_dbg(ERR_ZONE,
                                "%s: Failed to write SDIO_NXT_RD_DELAY2\n",
                                __func__);
                        return -1;
                }
        }

        if (dev->sdio_high_speed_enable) {
                rsi_dbg(INIT_ZONE, "%s: Enabling SDIO High speed\n", __func__);
                byte = 0x3;

                status = rsi_sdio_write_register(adapter,
                                                 function,
                                                 SDIO_REG_HIGH_SPEED,
                                                 &byte);
                if (status) {
                        rsi_dbg(ERR_ZONE,
                                "%s: Failed to enable SDIO high speed\n",
                                __func__);
                        return -1;
                }
        }

        /* This tells SDIO FIFO when to start read to host */
        rsi_dbg(INIT_ZONE, "%s: Initializing SDIO read start level\n", __func__);
        byte = 0x24;

        status = rsi_sdio_write_register(adapter,
                                         function,
                                         SDIO_READ_START_LVL,
                                         &byte);
        if (status) {
                rsi_dbg(ERR_ZONE,
                        "%s: Failed to write SDIO_READ_START_LVL\n", __func__);
                return -1;
        }

        rsi_dbg(INIT_ZONE, "%s: Initializing FIFO ctrl registers\n", __func__);
        byte = (128 - 32);

        status = rsi_sdio_write_register(adapter,
                                         function,
                                         SDIO_READ_FIFO_CTL,
                                         &byte);
        if (status) {
                rsi_dbg(ERR_ZONE,
                        "%s: Failed to write SDIO_READ_FIFO_CTL\n", __func__);
                return -1;
        }

        byte = 32;
        status = rsi_sdio_write_register(adapter,
                                         function,
                                         SDIO_WRITE_FIFO_CTL,
                                         &byte);
        if (status) {
                rsi_dbg(ERR_ZONE,
                        "%s: Failed to write SDIO_WRITE_FIFO_CTL\n", __func__);
                return -1;
        }

        return 0;
}

/**
 * rsi_rx_handler() - Read and process SDIO interrupts.
 * @adapter: Pointer to the adapter structure.
 *
 * Return: None.
 */
static void rsi_rx_handler(struct rsi_hw *adapter)
{
        struct rsi_common *common = adapter->priv;
        struct rsi_91x_sdiodev *dev = adapter->rsi_dev;
        int status;
        u8 isr_status = 0;
        u8 fw_status = 0;

        dev->rx_info.sdio_int_counter++;

        do {
                mutex_lock(&common->rx_lock);
                status = rsi_sdio_read_register(common->priv,
                                                RSI_FN1_INT_REGISTER,
                                                &isr_status);
                if (status) {
                        rsi_dbg(ERR_ZONE,
                                "%s: Failed to Read Intr Status Register\n",
                                __func__);
                        mutex_unlock(&common->rx_lock);
                        return;
                }
                adapter->interrupt_status = isr_status;

                if (isr_status == 0) {
                        rsi_set_event(&common->tx_thread.event);
                        dev->rx_info.sdio_intr_status_zero++;
                        mutex_unlock(&common->rx_lock);
                        return;
                }

                rsi_dbg(ISR_ZONE, "%s: Intr_status = %x %d %d\n",
                        __func__, isr_status, (1 << MSDU_PKT_PENDING),
                        (1 << FW_ASSERT_IND));

                if (isr_status & BIT(PKT_BUFF_AVAILABLE)) {
                        status = rsi_sdio_check_buffer_status(adapter, 0);
                        if (status < 0)
                                rsi_dbg(ERR_ZONE,
                                        "%s: Failed to check buffer status\n",
                                        __func__);
                        rsi_sdio_ack_intr(common->priv,
                                          BIT(PKT_BUFF_AVAILABLE));
                        rsi_set_event(&common->tx_thread.event);

                        rsi_dbg(ISR_ZONE, "%s: ==> BUFFER_AVAILABLE <==\n",
                                __func__);
                        dev->buff_status_updated = true;

                        isr_status &= ~BIT(PKT_BUFF_AVAILABLE);
                }

                if (isr_status & BIT(FW_ASSERT_IND)) {
                        rsi_dbg(ERR_ZONE, "%s: ==> FIRMWARE Assert <==\n",
                                __func__);
                        status = rsi_sdio_read_register(common->priv,
                                                        SDIO_FW_STATUS_REG,
                                                        &fw_status);
                        if (status) {
                                rsi_dbg(ERR_ZONE,
                                        "%s: Failed to read f/w reg\n",
                                        __func__);
                        } else {
                                rsi_dbg(ERR_ZONE,
                                        "%s: Firmware Status is 0x%x\n",
                                        __func__, fw_status);
                                rsi_sdio_ack_intr(common->priv,
                                                  BIT(FW_ASSERT_IND));
                        }

                        common->fsm_state = FSM_CARD_NOT_READY;

                        isr_status &= ~BIT(FW_ASSERT_IND);
                }

                if (isr_status & BIT(MSDU_PKT_PENDING)) {
                        rsi_dbg(ISR_ZONE, "Pkt pending interrupt\n");
                        dev->rx_info.total_sdio_msdu_pending_intr++;

                        status = rsi_process_pkt(common);
                        if (status) {
                                rsi_dbg(ERR_ZONE, "%s: Failed to read pkt\n",
                                        __func__);
                                mutex_unlock(&common->rx_lock);
                                return;
                        }

                        isr_status &= ~BIT(MSDU_PKT_PENDING);
                }

                if (isr_status) {
                        rsi_sdio_ack_intr(common->priv, isr_status);
                        dev->rx_info.total_sdio_unknown_intr++;
                        isr_status = 0;
                        rsi_dbg(ISR_ZONE, "Unknown Interrupt %x\n",
                                isr_status);
                }

                mutex_unlock(&common->rx_lock);
        } while (1);
}

/* This function is used to read buffer status register and
 * set relevant fields in rsi_91x_sdiodev struct.
 */
int rsi_sdio_check_buffer_status(struct rsi_hw *adapter, u8 q_num)
{
        struct rsi_common *common = adapter->priv;
        struct rsi_91x_sdiodev *dev = adapter->rsi_dev;
        u8 buf_status = 0;
        int status = 0;
        static int counter = 4;

        if (!dev->buff_status_updated && counter) {
                counter--;
                goto out;
        }

        dev->buff_status_updated = false;
        status = rsi_sdio_read_register(common->priv,
                                        RSI_DEVICE_BUFFER_STATUS_REGISTER,
                                        &buf_status);

        if (status) {
                rsi_dbg(ERR_ZONE,
                        "%s: Failed to read status register\n", __func__);
                return -1;
        }

        if (buf_status & (BIT(PKT_MGMT_BUFF_FULL))) {
                if (!dev->rx_info.mgmt_buffer_full)
                        dev->rx_info.mgmt_buf_full_counter++;
                dev->rx_info.mgmt_buffer_full = true;
        } else {
                dev->rx_info.mgmt_buffer_full = false;
        }

        if (buf_status & (BIT(PKT_BUFF_FULL))) {
                if (!dev->rx_info.buffer_full)
                        dev->rx_info.buf_full_counter++;
                dev->rx_info.buffer_full = true;
        } else {
                dev->rx_info.buffer_full = false;
        }

        if (buf_status & (BIT(PKT_BUFF_SEMI_FULL))) {
                if (!dev->rx_info.semi_buffer_full)
                        dev->rx_info.buf_semi_full_counter++;
                dev->rx_info.semi_buffer_full = true;
        } else {
                dev->rx_info.semi_buffer_full = false;
        }

        if (dev->rx_info.mgmt_buffer_full || dev->rx_info.buf_full_counter)
                counter = 1;
        else
                counter = 4;

out:
        if ((q_num == MGMT_SOFT_Q) && (dev->rx_info.mgmt_buffer_full))
                return QUEUE_FULL;

        if ((q_num < MGMT_SOFT_Q) && (dev->rx_info.buffer_full))
                return QUEUE_FULL;

        return QUEUE_NOT_FULL;
}

/**
 * rsi_sdio_determine_event_timeout() - This Function determines the event
 *                                      timeout duration.
 * @adapter: Pointer to the adapter structure.
 *
 * Return: timeout duration is returned.
 */
int rsi_sdio_determine_event_timeout(struct rsi_hw *adapter)
{
        struct rsi_91x_sdiodev *dev = adapter->rsi_dev;

        /* Once buffer full is seen, event timeout to occur every 2 msecs */
        if (dev->rx_info.buffer_full)
                return 2;

        return EVENT_WAIT_FOREVER;
}