fmdrv_common.c

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/*
 *  FM Driver for Connectivity chip of Texas Instruments.
 *
 *  This sub-module of FM driver is common for FM RX and TX
 *  functionality. This module is responsible for:
 *  1) Forming group of Channel-8 commands to perform particular
 *     functionality (eg., frequency set require more than
 *     one Channel-8 command to be sent to the chip).
 *  2) Sending each Channel-8 command to the chip and reading
 *     response back over Shared Transport.
 *  3) Managing TX and RX Queues and Tasklets.
 *  4) Handling FM Interrupt packet and taking appropriate action.
 *  5) Loading FM firmware to the chip (common, FM TX, and FM RX
 *     firmware files based on mode selection)
 *
 *  Copyright (C) 2011 Texas Instruments
 *  Author: Raja Mani <[email protected]>
 *  Author: Manjunatha Halli <[email protected]>
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License version 2 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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 */

#include <linux/module.h>
#include <linux/firmware.h>
#include <linux/delay.h>
#include "fmdrv.h"
#include "fmdrv_v4l2.h"
#include "fmdrv_common.h"
#include <linux/ti_wilink_st.h>
#include "fmdrv_rx.h"
#include "fmdrv_tx.h"

/* Region info */
static struct region_info region_configs[] = {
    /* Europe/US */
    {
     .chanl_space = FM_CHANNEL_SPACING_200KHZ * FM_FREQ_MUL,
     .bot_freq = 87500, /* 87.5 MHz */
     .top_freq = 108000,    /* 108 MHz */
     .fm_band = 0,
     },
    /* Japan */
    {
     .chanl_space = FM_CHANNEL_SPACING_200KHZ * FM_FREQ_MUL,
     .bot_freq = 76000, /* 76 MHz */
     .top_freq = 90000, /* 90 MHz */
     .fm_band = 1,
     },
};

/* Band selection */
static u8 default_radio_region; /* Europe/US */
module_param(default_radio_region, byte, 0);
MODULE_PARM_DESC(default_radio_region, "Region: 0=Europe/US, 1=Japan");

/* RDS buffer blocks */
static u32 default_rds_buf = 300;
module_param(default_rds_buf, uint, 0444);
MODULE_PARM_DESC(rds_buf, "RDS buffer entries");

/* Radio Nr */
static u32 radio_nr = -1;
module_param(radio_nr, int, 0444);
MODULE_PARM_DESC(radio_nr, "Radio Nr");

/* FM irq handlers forward declaration */
static void fm_irq_send_flag_getcmd(struct fmdev *);
static void fm_irq_handle_flag_getcmd_resp(struct fmdev *);
static void fm_irq_handle_hw_malfunction(struct fmdev *);
static void fm_irq_handle_rds_start(struct fmdev *);
static void fm_irq_send_rdsdata_getcmd(struct fmdev *);
static void fm_irq_handle_rdsdata_getcmd_resp(struct fmdev *);
static void fm_irq_handle_rds_finish(struct fmdev *);
static void fm_irq_handle_tune_op_ended(struct fmdev *);
static void fm_irq_handle_power_enb(struct fmdev *);
static void fm_irq_handle_low_rssi_start(struct fmdev *);
static void fm_irq_afjump_set_pi(struct fmdev *);
static void fm_irq_handle_set_pi_resp(struct fmdev *);
static void fm_irq_afjump_set_pimask(struct fmdev *);
static void fm_irq_handle_set_pimask_resp(struct fmdev *);
static void fm_irq_afjump_setfreq(struct fmdev *);
static void fm_irq_handle_setfreq_resp(struct fmdev *);
static void fm_irq_afjump_enableint(struct fmdev *);
static void fm_irq_afjump_enableint_resp(struct fmdev *);
static void fm_irq_start_afjump(struct fmdev *);
static void fm_irq_handle_start_afjump_resp(struct fmdev *);
static void fm_irq_afjump_rd_freq(struct fmdev *);
static void fm_irq_afjump_rd_freq_resp(struct fmdev *);
static void fm_irq_handle_low_rssi_finish(struct fmdev *);
static void fm_irq_send_intmsk_cmd(struct fmdev *);
static void fm_irq_handle_intmsk_cmd_resp(struct fmdev *);

/*
 * When FM common module receives interrupt packet, following handlers
 * will be executed one after another to service the interrupt(s)
 */
enum fmc_irq_handler_index {
    FM_SEND_FLAG_GETCMD_IDX,
    FM_HANDLE_FLAG_GETCMD_RESP_IDX,

    /* HW malfunction irq handler */
    FM_HW_MAL_FUNC_IDX,

    /* RDS threshold reached irq handler */
    FM_RDS_START_IDX,
    FM_RDS_SEND_RDS_GETCMD_IDX,
    FM_RDS_HANDLE_RDS_GETCMD_RESP_IDX,
    FM_RDS_FINISH_IDX,

    /* Tune operation ended irq handler */
    FM_HW_TUNE_OP_ENDED_IDX,

    /* TX power enable irq handler */
    FM_HW_POWER_ENB_IDX,

    /* Low RSSI irq handler */
    FM_LOW_RSSI_START_IDX,
    FM_AF_JUMP_SETPI_IDX,
    FM_AF_JUMP_HANDLE_SETPI_RESP_IDX,
    FM_AF_JUMP_SETPI_MASK_IDX,
    FM_AF_JUMP_HANDLE_SETPI_MASK_RESP_IDX,
    FM_AF_JUMP_SET_AF_FREQ_IDX,
    FM_AF_JUMP_HANDLE_SET_AFFREQ_RESP_IDX,
    FM_AF_JUMP_ENABLE_INT_IDX,
    FM_AF_JUMP_ENABLE_INT_RESP_IDX,
    FM_AF_JUMP_START_AFJUMP_IDX,
    FM_AF_JUMP_HANDLE_START_AFJUMP_RESP_IDX,
    FM_AF_JUMP_RD_FREQ_IDX,
    FM_AF_JUMP_RD_FREQ_RESP_IDX,
    FM_LOW_RSSI_FINISH_IDX,

    /* Interrupt process post action */
    FM_SEND_INTMSK_CMD_IDX,
    FM_HANDLE_INTMSK_CMD_RESP_IDX,
};

/* FM interrupt handler table */
static int_handler_prototype int_handler_table[] = {
    fm_irq_send_flag_getcmd,
    fm_irq_handle_flag_getcmd_resp,
    fm_irq_handle_hw_malfunction,
    fm_irq_handle_rds_start, /* RDS threshold reached irq handler */
    fm_irq_send_rdsdata_getcmd,
    fm_irq_handle_rdsdata_getcmd_resp,
    fm_irq_handle_rds_finish,
    fm_irq_handle_tune_op_ended,
    fm_irq_handle_power_enb, /* TX power enable irq handler */
    fm_irq_handle_low_rssi_start,
    fm_irq_afjump_set_pi,
    fm_irq_handle_set_pi_resp,
    fm_irq_afjump_set_pimask,
    fm_irq_handle_set_pimask_resp,
    fm_irq_afjump_setfreq,
    fm_irq_handle_setfreq_resp,
    fm_irq_afjump_enableint,
    fm_irq_afjump_enableint_resp,
    fm_irq_start_afjump,
    fm_irq_handle_start_afjump_resp,
    fm_irq_afjump_rd_freq,
    fm_irq_afjump_rd_freq_resp,
    fm_irq_handle_low_rssi_finish,
    fm_irq_send_intmsk_cmd, /* Interrupt process post action */
    fm_irq_handle_intmsk_cmd_resp
};

long (*g_st_write) (struct sk_buff *skb);
static struct completion wait_for_fmdrv_reg_comp;

static inline void fm_irq_call(struct fmdev *fmdev)
{
    fmdev->irq_info.handlers[fmdev->irq_info.stage](fmdev);
}

/* Continue next function in interrupt handler table */
static inline void fm_irq_call_stage(struct fmdev *fmdev, u8 stage)
{
    fmdev->irq_info.stage = stage;
    fm_irq_call(fmdev);
}

static inline void fm_irq_timeout_stage(struct fmdev *fmdev, u8 stage)
{
    fmdev->irq_info.stage = stage;
    mod_timer(&fmdev->irq_info.timer, jiffies + FM_DRV_TX_TIMEOUT);
}

#ifdef FM_DUMP_TXRX_PKT
 /* To dump outgoing FM Channel-8 packets */
inline void dump_tx_skb_data(struct sk_buff *skb)
{
    int len, len_org;
    u8 index;
    struct fm_cmd_msg_hdr *cmd_hdr;

    cmd_hdr = (struct fm_cmd_msg_hdr *)skb->data;
    printk(KERN_INFO "<<%shdr:%02x len:%02x opcode:%02x type:%s dlen:%02x",
           fm_cb(skb)->completion ? " " : "*", cmd_hdr->hdr,
           cmd_hdr->len, cmd_hdr->op,
           cmd_hdr->rd_wr ? "RD" : "WR", cmd_hdr->dlen);

    len_org = skb->len - FM_CMD_MSG_HDR_SIZE;
    if (len_org > 0) {
        printk("\n   data(%d): ", cmd_hdr->dlen);
        len = min(len_org, 14);
        for (index = 0; index < len; index++)
            printk("%x ",
                   skb->data[FM_CMD_MSG_HDR_SIZE + index]);
        printk("%s", (len_org > 14) ? ".." : "");
    }
    printk("\n");
}

 /* To dump incoming FM Channel-8 packets */
inline void dump_rx_skb_data(struct sk_buff *skb)
{
    int len, len_org;
    u8 index;
    struct fm_event_msg_hdr *evt_hdr;

    evt_hdr = (struct fm_event_msg_hdr *)skb->data;
    printk(KERN_INFO ">> hdr:%02x len:%02x sts:%02x numhci:%02x "
        "opcode:%02x type:%s dlen:%02x", evt_hdr->hdr, evt_hdr->len,
        evt_hdr->status, evt_hdr->num_fm_hci_cmds, evt_hdr->op,
        (evt_hdr->rd_wr) ? "RD" : "WR", evt_hdr->dlen);

    len_org = skb->len - FM_EVT_MSG_HDR_SIZE;
    if (len_org > 0) {
        printk("\n   data(%d): ", evt_hdr->dlen);
        len = min(len_org, 14);
        for (index = 0; index < len; index++)
            printk("%x ",
                   skb->data[FM_EVT_MSG_HDR_SIZE + index]);
        printk("%s", (len_org > 14) ? ".." : "");
    }
    printk("\n");
}
#endif

void fmc_update_region_info(struct fmdev *fmdev, u8 region_to_set)
{
    fmdev->rx.region = region_configs[region_to_set];
}

/*
 * FM common sub-module will schedule this tasklet whenever it receives
 * FM packet from ST driver.
 */
static void recv_tasklet(unsigned long arg)
{
    struct fmdev *fmdev;
    struct fm_irq *irq_info;
    struct fm_event_msg_hdr *evt_hdr;
    struct sk_buff *skb;
    u8 num_fm_hci_cmds;
    unsigned long flags;

    fmdev = (struct fmdev *)arg;
    irq_info = &fmdev->irq_info;
    /* Process all packets in the RX queue */
    while ((skb = skb_dequeue(&fmdev->rx_q))) {
        if (skb->len < sizeof(struct fm_event_msg_hdr)) {
            fmerr("skb(%p) has only %d bytes, "
                "at least need %zu bytes to decode\n", skb,
                skb->len, sizeof(struct fm_event_msg_hdr));
            kfree_skb(skb);
            continue;
        }

        evt_hdr = (void *)skb->data;
        num_fm_hci_cmds = evt_hdr->num_fm_hci_cmds;

        /* FM interrupt packet? */
        if (evt_hdr->op == FM_INTERRUPT) {
            /* FM interrupt handler started already? */
            if (!test_bit(FM_INTTASK_RUNNING, &fmdev->flag)) {
                set_bit(FM_INTTASK_RUNNING, &fmdev->flag);
                if (irq_info->stage != 0) {
                    fmerr("Inval stage resetting to zero\n");
                    irq_info->stage = 0;
                }

                /*
                 * Execute first function in interrupt handler
                 * table.
                 */
                irq_info->handlers[irq_info->stage](fmdev);
            } else {
                set_bit(FM_INTTASK_SCHEDULE_PENDING, &fmdev->flag);
            }
            kfree_skb(skb);
        }
        /* Anyone waiting for this with completion handler? */
        else if (evt_hdr->op == fmdev->pre_op && fmdev->resp_comp != NULL) {

            spin_lock_irqsave(&fmdev->resp_skb_lock, flags);
            fmdev->resp_skb = skb;
            spin_unlock_irqrestore(&fmdev->resp_skb_lock, flags);
            complete(fmdev->resp_comp);

            fmdev->resp_comp = NULL;
            atomic_set(&fmdev->tx_cnt, 1);
        }
        /* Is this for interrupt handler? */
        else if (evt_hdr->op == fmdev->pre_op && fmdev->resp_comp == NULL) {
            if (fmdev->resp_skb != NULL)
                fmerr("Response SKB ptr not NULL\n");

            spin_lock_irqsave(&fmdev->resp_skb_lock, flags);
            fmdev->resp_skb = skb;
            spin_unlock_irqrestore(&fmdev->resp_skb_lock, flags);

            /* Execute interrupt handler where state index points */
            irq_info->handlers[irq_info->stage](fmdev);

            kfree_skb(skb);
            atomic_set(&fmdev->tx_cnt, 1);
        } else {
            fmerr("Nobody claimed SKB(%p),purging\n", skb);
        }

        /*
         * Check flow control field. If Num_FM_HCI_Commands field is
         * not zero, schedule FM TX tasklet.
         */
        if (num_fm_hci_cmds && atomic_read(&fmdev->tx_cnt))
            if (!skb_queue_empty(&fmdev->tx_q))
                tasklet_schedule(&fmdev->tx_task);
    }
}

/* FM send tasklet: is scheduled when FM packet has to be sent to chip */
static void send_tasklet(unsigned long arg)
{
    struct fmdev *fmdev;
    struct sk_buff *skb;
    int len;

    fmdev = (struct fmdev *)arg;

    if (!atomic_read(&fmdev->tx_cnt))
        return;

    /* Check, is there any timeout happened to last transmitted packet */
    if ((jiffies - fmdev->last_tx_jiffies) > FM_DRV_TX_TIMEOUT) {
        fmerr("TX timeout occurred\n");
        atomic_set(&fmdev->tx_cnt, 1);
    }

    /* Send queued FM TX packets */
    skb = skb_dequeue(&fmdev->tx_q);
    if (!skb)
        return;

    atomic_dec(&fmdev->tx_cnt);
    fmdev->pre_op = fm_cb(skb)->fm_op;

    if (fmdev->resp_comp != NULL)
        fmerr("Response completion handler is not NULL\n");

    fmdev->resp_comp = fm_cb(skb)->completion;

    /* Write FM packet to ST driver */
    len = g_st_write(skb);
    if (len < 0) {
        kfree_skb(skb);
        fmdev->resp_comp = NULL;
        fmerr("TX tasklet failed to send skb(%p)\n", skb);
        atomic_set(&fmdev->tx_cnt, 1);
    } else {
        fmdev->last_tx_jiffies = jiffies;
    }
}

/*
 * Queues FM Channel-8 packet to FM TX queue and schedules FM TX tasklet for
 * transmission
 */
static int fm_send_cmd(struct fmdev *fmdev, u8 fm_op, u16 type, void *payload,
        int payload_len, struct completion *wait_completion)
{
    struct sk_buff *skb;
    struct fm_cmd_msg_hdr *hdr;
    int size;

    if (fm_op >= FM_INTERRUPT) {
        fmerr("Invalid fm opcode - %d\n", fm_op);
        return -EINVAL;
    }
    if (test_bit(FM_FW_DW_INPROGRESS, &fmdev->flag) && payload == NULL) {
        fmerr("Payload data is NULL during fw download\n");
        return -EINVAL;
    }
    if (!test_bit(FM_FW_DW_INPROGRESS, &fmdev->flag))
        size =
            FM_CMD_MSG_HDR_SIZE + ((payload == NULL) ? 0 : payload_len);
    else
        size = payload_len;

    skb = alloc_skb(size, GFP_ATOMIC);
    if (!skb) {
        fmerr("No memory to create new SKB\n");
        return -ENOMEM;
    }
    /*
     * Don't fill FM header info for the commands which come from
     * FM firmware file.
     */
    if (!test_bit(FM_FW_DW_INPROGRESS, &fmdev->flag) ||
            test_bit(FM_INTTASK_RUNNING, &fmdev->flag)) {
        /* Fill command header info */
        hdr = (struct fm_cmd_msg_hdr *)skb_put(skb, FM_CMD_MSG_HDR_SIZE);
        hdr->hdr = FM_PKT_LOGICAL_CHAN_NUMBER;  /* 0x08 */

        /* 3 (fm_opcode,rd_wr,dlen) + payload len) */
        hdr->len = ((payload == NULL) ? 0 : payload_len) + 3;

        /* FM opcode */
        hdr->op = fm_op;

        /* read/write type */
        hdr->rd_wr = type;
        hdr->dlen = payload_len;
        fm_cb(skb)->fm_op = fm_op;

        /*
         * If firmware download has finished and the command is
         * not a read command then payload is != NULL - a write
         * command with u16 payload - convert to be16
         */
        if (payload != NULL)
            *(u16 *)payload = cpu_to_be16(*(u16 *)payload);

    } else if (payload != NULL) {
        fm_cb(skb)->fm_op = *((u8 *)payload + 2);
    }
    if (payload != NULL)
        memcpy(skb_put(skb, payload_len), payload, payload_len);

    fm_cb(skb)->completion = wait_completion;
    skb_queue_tail(&fmdev->tx_q, skb);
    tasklet_schedule(&fmdev->tx_task);

    return 0;
}

/* Sends FM Channel-8 command to the chip and waits for the response */
int fmc_send_cmd(struct fmdev *fmdev, u8 fm_op, u16 type, void *payload,
        unsigned int payload_len, void *response, int *response_len)
{
    struct sk_buff *skb;
    struct fm_event_msg_hdr *evt_hdr;
    unsigned long flags;
    int ret;

    init_completion(&fmdev->maintask_comp);
    ret = fm_send_cmd(fmdev, fm_op, type, payload, payload_len,
                &fmdev->maintask_comp);
    if (ret)
        return ret;

    if (!wait_for_completion_timeout(&fmdev->maintask_comp,
                     FM_DRV_TX_TIMEOUT)) {
        fmerr("Timeout(%d sec),didn't get reg"
               "completion signal from RX tasklet\n",
               jiffies_to_msecs(FM_DRV_TX_TIMEOUT) / 1000);
        return -ETIMEDOUT;
    }
    if (!fmdev->resp_skb) {
        fmerr("Response SKB is missing\n");
        return -EFAULT;
    }
    spin_lock_irqsave(&fmdev->resp_skb_lock, flags);
    skb = fmdev->resp_skb;
    fmdev->resp_skb = NULL;
    spin_unlock_irqrestore(&fmdev->resp_skb_lock, flags);

    evt_hdr = (void *)skb->data;
    if (evt_hdr->status != 0) {
        fmerr("Received event pkt status(%d) is not zero\n",
               evt_hdr->status);
        kfree_skb(skb);
        return -EIO;
    }
    /* Send response data to caller */
    if (response != NULL && response_len != NULL && evt_hdr->dlen) {
        /* Skip header info and copy only response data */
        skb_pull(skb, sizeof(struct fm_event_msg_hdr));
        memcpy(response, skb->data, evt_hdr->dlen);
        *response_len = evt_hdr->dlen;
    } else if (response_len != NULL && evt_hdr->dlen == 0) {
        *response_len = 0;
    }
    kfree_skb(skb);

    return 0;
}

/* --- Helper functions used in FM interrupt handlers ---*/
static inline int check_cmdresp_status(struct fmdev *fmdev,
        struct sk_buff **skb)
{
    struct fm_event_msg_hdr *fm_evt_hdr;
    unsigned long flags;

    del_timer(&fmdev->irq_info.timer);

    spin_lock_irqsave(&fmdev->resp_skb_lock, flags);
    *skb = fmdev->resp_skb;
    fmdev->resp_skb = NULL;
    spin_unlock_irqrestore(&fmdev->resp_skb_lock, flags);

    fm_evt_hdr = (void *)(*skb)->data;
    if (fm_evt_hdr->status != 0) {
        fmerr("irq: opcode %x response status is not zero "
                "Initiating irq recovery process\n",
                fm_evt_hdr->op);

        mod_timer(&fmdev->irq_info.timer, jiffies + FM_DRV_TX_TIMEOUT);
        return -1;
    }

    return 0;
}

static inline void fm_irq_common_cmd_resp_helper(struct fmdev *fmdev, u8 stage)
{
    struct sk_buff *skb;

    if (!check_cmdresp_status(fmdev, &skb))
        fm_irq_call_stage(fmdev, stage);
}

/*
 * Interrupt process timeout handler.
 * One of the irq handler did not get proper response from the chip. So take
 * recovery action here. FM interrupts are disabled in the beginning of
 * interrupt process. Therefore reset stage index to re-enable default
 * interrupts. So that next interrupt will be processed as usual.
 */
static void int_timeout_handler(unsigned long data)
{
    struct fmdev *fmdev;
    struct fm_irq *fmirq;

    fmdbg("irq: timeout,trying to re-enable fm interrupts\n");
    fmdev = (struct fmdev *)data;
    fmirq = &fmdev->irq_info;
    fmirq->retry++;

    if (fmirq->retry > FM_IRQ_TIMEOUT_RETRY_MAX) {
        /* Stop recovery action (interrupt reenable process) and
         * reset stage index & retry count values */
        fmirq->stage = 0;
        fmirq->retry = 0;
        fmerr("Recovery action failed during"
                "irq processing, max retry reached\n");
        return;
    }
    fm_irq_call_stage(fmdev, FM_SEND_INTMSK_CMD_IDX);
}

/* --------- FM interrupt handlers ------------*/
static void fm_irq_send_flag_getcmd(struct fmdev *fmdev)
{
    u16 flag;

    /* Send FLAG_GET command , to know the source of interrupt */
    if (!fm_send_cmd(fmdev, FLAG_GET, REG_RD, NULL, sizeof(flag), NULL))
        fm_irq_timeout_stage(fmdev, FM_HANDLE_FLAG_GETCMD_RESP_IDX);
}

static void fm_irq_handle_flag_getcmd_resp(struct fmdev *fmdev)
{
    struct sk_buff *skb;
    struct fm_event_msg_hdr *fm_evt_hdr;

    if (check_cmdresp_status(fmdev, &skb))
        return;

    fm_evt_hdr = (void *)skb->data;

    /* Skip header info and copy only response data */
    skb_pull(skb, sizeof(struct fm_event_msg_hdr));
    memcpy(&fmdev->irq_info.flag, skb->data, fm_evt_hdr->dlen);

    fmdev->irq_info.flag = be16_to_cpu(fmdev->irq_info.flag);
    fmdbg("irq: flag register(0x%x)\n", fmdev->irq_info.flag);

    /* Continue next function in interrupt handler table */
    fm_irq_call_stage(fmdev, FM_HW_MAL_FUNC_IDX);
}

static void fm_irq_handle_hw_malfunction(struct fmdev *fmdev)
{
    if (fmdev->irq_info.flag & FM_MAL_EVENT & fmdev->irq_info.mask)
        fmerr("irq: HW MAL int received - do nothing\n");

    /* Continue next function in interrupt handler table */
    fm_irq_call_stage(fmdev, FM_RDS_START_IDX);
}

static void fm_irq_handle_rds_start(struct fmdev *fmdev)
{
    if (fmdev->irq_info.flag & FM_RDS_EVENT & fmdev->irq_info.mask) {
        fmdbg("irq: rds threshold reached\n");
        fmdev->irq_info.stage = FM_RDS_SEND_RDS_GETCMD_IDX;
    } else {
        /* Continue next function in interrupt handler table */
        fmdev->irq_info.stage = FM_HW_TUNE_OP_ENDED_IDX;
    }

    fm_irq_call(fmdev);
}

static void fm_irq_send_rdsdata_getcmd(struct fmdev *fmdev)
{
    /* Send the command to read RDS data from the chip */
    if (!fm_send_cmd(fmdev, RDS_DATA_GET, REG_RD, NULL,
                (FM_RX_RDS_FIFO_THRESHOLD * 3), NULL))
        fm_irq_timeout_stage(fmdev, FM_RDS_HANDLE_RDS_GETCMD_RESP_IDX);
}

/* Keeps track of current RX channel AF (Alternate Frequency) */
static void fm_rx_update_af_cache(struct fmdev *fmdev, u8 af)
{
    struct tuned_station_info *stat_info = &fmdev->rx.stat_info;
    u8 reg_idx = fmdev->rx.region.fm_band;
    u8 index;
    u32 freq;

    /* First AF indicates the number of AF follows. Reset the list */
    if ((af >= FM_RDS_1_AF_FOLLOWS) && (af <= FM_RDS_25_AF_FOLLOWS)) {
        fmdev->rx.stat_info.af_list_max = (af - FM_RDS_1_AF_FOLLOWS + 1);
        fmdev->rx.stat_info.afcache_size = 0;
        fmdbg("No of expected AF : %d\n", fmdev->rx.stat_info.af_list_max);
        return;
    }

    if (af < FM_RDS_MIN_AF)
        return;
    if (reg_idx == FM_BAND_EUROPE_US && af > FM_RDS_MAX_AF)
        return;
    if (reg_idx == FM_BAND_JAPAN && af > FM_RDS_MAX_AF_JAPAN)
        return;

    freq = fmdev->rx.region.bot_freq + (af * 100);
    if (freq == fmdev->rx.freq) {
        fmdbg("Current freq(%d) is matching with received AF(%d)\n",
                fmdev->rx.freq, freq);
        return;
    }
    /* Do check in AF cache */
    for (index = 0; index < stat_info->afcache_size; index++) {
        if (stat_info->af_cache[index] == freq)
            break;
    }
    /* Reached the limit of the list - ignore the next AF */
    if (index == stat_info->af_list_max) {
        fmdbg("AF cache is full\n");
        return;
    }
    /*
     * If we reached the end of the list then this AF is not
     * in the list - add it.
     */
    if (index == stat_info->afcache_size) {
        fmdbg("Storing AF %d to cache index %d\n", freq, index);
        stat_info->af_cache[index] = freq;
        stat_info->afcache_size++;
    }
}

/*
 * Converts RDS buffer data from big endian format
 * to little endian format.
 */
static void fm_rdsparse_swapbytes(struct fmdev *fmdev,
        struct fm_rdsdata_format *rds_format)
{
    u8 byte1;
    u8 index = 0;
    u8 *rds_buff;

    /*
     * Since in Orca the 2 RDS Data bytes are in little endian and
     * in Dolphin they are in big endian, the parsing of the RDS data
     * is chip dependent
     */
    if (fmdev->asci_id != 0x6350) {
        rds_buff = &rds_format->data.groupdatabuff.buff[0];
        while (index + 1 < FM_RX_RDS_INFO_FIELD_MAX) {
            byte1 = rds_buff[index];
            rds_buff[index] = rds_buff[index + 1];
            rds_buff[index + 1] = byte1;
            index += 2;
        }
    }
}

static void fm_irq_handle_rdsdata_getcmd_resp(struct fmdev *fmdev)
{
    struct sk_buff *skb;
    struct fm_rdsdata_format rds_fmt;
    struct fm_rds *rds = &fmdev->rx.rds;
    unsigned long group_idx, flags;
    u8 *rds_data, meta_data, tmpbuf[3];
    u8 type, blk_idx;
    u16 cur_picode;
    u32 rds_len;

    if (check_cmdresp_status(fmdev, &skb))
        return;

    /* Skip header info */
    skb_pull(skb, sizeof(struct fm_event_msg_hdr));
    rds_data = skb->data;
    rds_len = skb->len;

    /* Parse the RDS data */
    while (rds_len >= FM_RDS_BLK_SIZE) {
        meta_data = rds_data[2];
        /* Get the type: 0=A, 1=B, 2=C, 3=C', 4=D, 5=E */
        type = (meta_data & 0x07);

        /* Transform the blk type into index sequence (0, 1, 2, 3, 4) */
        blk_idx = (type <= FM_RDS_BLOCK_C ? type : (type - 1));
        fmdbg("Block index:%d(%s)\n", blk_idx,
               (meta_data & FM_RDS_STATUS_ERR_MASK) ? "Bad" : "Ok");

        if ((meta_data & FM_RDS_STATUS_ERR_MASK) != 0)
            break;

        if (blk_idx < FM_RDS_BLK_IDX_A || blk_idx > FM_RDS_BLK_IDX_D) {
            fmdbg("Block sequence mismatch\n");
            rds->last_blk_idx = -1;
            break;
        }

        /* Skip checkword (control) byte and copy only data byte */
        memcpy(&rds_fmt.data.groupdatabuff.
                buff[blk_idx * (FM_RDS_BLK_SIZE - 1)],
                rds_data, (FM_RDS_BLK_SIZE - 1));

        rds->last_blk_idx = blk_idx;

        /* If completed a whole group then handle it */
        if (blk_idx == FM_RDS_BLK_IDX_D) {
            fmdbg("Good block received\n");
            fm_rdsparse_swapbytes(fmdev, &rds_fmt);

            /*
             * Extract PI code and store in local cache.
             * We need this during AF switch processing.
             */
            cur_picode = be16_to_cpu(rds_fmt.data.groupgeneral.pidata);
            if (fmdev->rx.stat_info.picode != cur_picode)
                fmdev->rx.stat_info.picode = cur_picode;

            fmdbg("picode:%d\n", cur_picode);

            group_idx = (rds_fmt.data.groupgeneral.blk_b[0] >> 3);
            fmdbg("(fmdrv):Group:%ld%s\n", group_idx/2,
                    (group_idx % 2) ? "B" : "A");

            group_idx = 1 << (rds_fmt.data.groupgeneral.blk_b[0] >> 3);
            if (group_idx == FM_RDS_GROUP_TYPE_MASK_0A) {
                fm_rx_update_af_cache(fmdev, rds_fmt.data.group0A.af[0]);
                fm_rx_update_af_cache(fmdev, rds_fmt.data.group0A.af[1]);
            }
        }
        rds_len -= FM_RDS_BLK_SIZE;
        rds_data += FM_RDS_BLK_SIZE;
    }

    /* Copy raw rds data to internal rds buffer */
    rds_data = skb->data;
    rds_len = skb->len;

    spin_lock_irqsave(&fmdev->rds_buff_lock, flags);
    while (rds_len > 0) {
        /*
         * Fill RDS buffer as per V4L2 specification.
         * Store control byte
         */
        type = (rds_data[2] & 0x07);
        blk_idx = (type <= FM_RDS_BLOCK_C ? type : (type - 1));
        tmpbuf[2] = blk_idx;    /* Offset name */
        tmpbuf[2] |= blk_idx << 3;  /* Received offset */

        /* Store data byte */
        tmpbuf[0] = rds_data[0];
        tmpbuf[1] = rds_data[1];

        memcpy(&rds->buff[rds->wr_idx], &tmpbuf, FM_RDS_BLK_SIZE);
        rds->wr_idx = (rds->wr_idx + FM_RDS_BLK_SIZE) % rds->buf_size;

        /* Check for overflow & start over */
        if (rds->wr_idx == rds->rd_idx) {
            fmdbg("RDS buffer overflow\n");
            rds->wr_idx = 0;
            rds->rd_idx = 0;
            break;
        }
        rds_len -= FM_RDS_BLK_SIZE;
        rds_data += FM_RDS_BLK_SIZE;
    }
    spin_unlock_irqrestore(&fmdev->rds_buff_lock, flags);

    /* Wakeup read queue */
    if (rds->wr_idx != rds->rd_idx)
        wake_up_interruptible(&rds->read_queue);

    fm_irq_call_stage(fmdev, FM_RDS_FINISH_IDX);
}

static void fm_irq_handle_rds_finish(struct fmdev *fmdev)
{
    fm_irq_call_stage(fmdev, FM_HW_TUNE_OP_ENDED_IDX);
}

static void fm_irq_handle_tune_op_ended(struct fmdev *fmdev)
{
    if (fmdev->irq_info.flag & (FM_FR_EVENT | FM_BL_EVENT) & fmdev->
        irq_info.mask) {
        fmdbg("irq: tune ended/bandlimit reached\n");
        if (test_and_clear_bit(FM_AF_SWITCH_INPROGRESS, &fmdev->flag)) {
            fmdev->irq_info.stage = FM_AF_JUMP_RD_FREQ_IDX;
        } else {
            complete(&fmdev->maintask_comp);
            fmdev->irq_info.stage = FM_HW_POWER_ENB_IDX;
        }
    } else
        fmdev->irq_info.stage = FM_HW_POWER_ENB_IDX;

    fm_irq_call(fmdev);
}

static void fm_irq_handle_power_enb(struct fmdev *fmdev)
{
    if (fmdev->irq_info.flag & FM_POW_ENB_EVENT) {
        fmdbg("irq: Power Enabled/Disabled\n");
        complete(&fmdev->maintask_comp);
    }

    fm_irq_call_stage(fmdev, FM_LOW_RSSI_START_IDX);
}

static void fm_irq_handle_low_rssi_start(struct fmdev *fmdev)
{
    if ((fmdev->rx.af_mode == FM_RX_RDS_AF_SWITCH_MODE_ON) &&
        (fmdev->irq_info.flag & FM_LEV_EVENT & fmdev->irq_info.mask) &&
        (fmdev->rx.freq != FM_UNDEFINED_FREQ) &&
        (fmdev->rx.stat_info.afcache_size != 0)) {
        fmdbg("irq: rssi level has fallen below threshold level\n");

        /* Disable further low RSSI interrupts */
        fmdev->irq_info.mask &= ~FM_LEV_EVENT;

        fmdev->rx.afjump_idx = 0;
        fmdev->rx.freq_before_jump = fmdev->rx.freq;
        fmdev->irq_info.stage = FM_AF_JUMP_SETPI_IDX;
    } else {
        /* Continue next function in interrupt handler table */
        fmdev->irq_info.stage = FM_SEND_INTMSK_CMD_IDX;
    }

    fm_irq_call(fmdev);
}

static void fm_irq_afjump_set_pi(struct fmdev *fmdev)
{
    u16 payload;

    /* Set PI code - must be updated if the AF list is not empty */
    payload = fmdev->rx.stat_info.picode;
    if (!fm_send_cmd(fmdev, RDS_PI_SET, REG_WR, &payload, sizeof(payload), NULL))
        fm_irq_timeout_stage(fmdev, FM_AF_JUMP_HANDLE_SETPI_RESP_IDX);
}

static void fm_irq_handle_set_pi_resp(struct fmdev *fmdev)
{
    fm_irq_common_cmd_resp_helper(fmdev, FM_AF_JUMP_SETPI_MASK_IDX);
}

/*
 * Set PI mask.
 * 0xFFFF = Enable PI code matching
 * 0x0000 = Disable PI code matching
 */
static void fm_irq_afjump_set_pimask(struct fmdev *fmdev)
{
    u16 payload;

    payload = 0x0000;
    if (!fm_send_cmd(fmdev, RDS_PI_MASK_SET, REG_WR, &payload, sizeof(payload), NULL))
        fm_irq_timeout_stage(fmdev, FM_AF_JUMP_HANDLE_SETPI_MASK_RESP_IDX);
}

static void fm_irq_handle_set_pimask_resp(struct fmdev *fmdev)
{
    fm_irq_common_cmd_resp_helper(fmdev, FM_AF_JUMP_SET_AF_FREQ_IDX);
}

static void fm_irq_afjump_setfreq(struct fmdev *fmdev)
{
    u16 frq_index;
    u16 payload;

    fmdbg("Swtich to %d KHz\n", fmdev->rx.stat_info.af_cache[fmdev->rx.afjump_idx]);
    frq_index = (fmdev->rx.stat_info.af_cache[fmdev->rx.afjump_idx] -
         fmdev->rx.region.bot_freq) / FM_FREQ_MUL;

    payload = frq_index;
    if (!fm_send_cmd(fmdev, AF_FREQ_SET, REG_WR, &payload, sizeof(payload), NULL))
        fm_irq_timeout_stage(fmdev, FM_AF_JUMP_HANDLE_SET_AFFREQ_RESP_IDX);
}

static void fm_irq_handle_setfreq_resp(struct fmdev *fmdev)
{
    fm_irq_common_cmd_resp_helper(fmdev, FM_AF_JUMP_ENABLE_INT_IDX);
}

static void fm_irq_afjump_enableint(struct fmdev *fmdev)
{
    u16 payload;

    /* Enable FR (tuning operation ended) interrupt */
    payload = FM_FR_EVENT;
    if (!fm_send_cmd(fmdev, INT_MASK_SET, REG_WR, &payload, sizeof(payload), NULL))
        fm_irq_timeout_stage(fmdev, FM_AF_JUMP_ENABLE_INT_RESP_IDX);
}

static void fm_irq_afjump_enableint_resp(struct fmdev *fmdev)
{
    fm_irq_common_cmd_resp_helper(fmdev, FM_AF_JUMP_START_AFJUMP_IDX);
}

static void fm_irq_start_afjump(struct fmdev *fmdev)
{
    u16 payload;

    payload = FM_TUNER_AF_JUMP_MODE;
    if (!fm_send_cmd(fmdev, TUNER_MODE_SET, REG_WR, &payload,
            sizeof(payload), NULL))
        fm_irq_timeout_stage(fmdev, FM_AF_JUMP_HANDLE_START_AFJUMP_RESP_IDX);
}

static void fm_irq_handle_start_afjump_resp(struct fmdev *fmdev)
{
    struct sk_buff *skb;

    if (check_cmdresp_status(fmdev, &skb))
        return;

    fmdev->irq_info.stage = FM_SEND_FLAG_GETCMD_IDX;
    set_bit(FM_AF_SWITCH_INPROGRESS, &fmdev->flag);
    clear_bit(FM_INTTASK_RUNNING, &fmdev->flag);
}

static void fm_irq_afjump_rd_freq(struct fmdev *fmdev)
{
    u16 payload;

    if (!fm_send_cmd(fmdev, FREQ_SET, REG_RD, NULL, sizeof(payload), NULL))
        fm_irq_timeout_stage(fmdev, FM_AF_JUMP_RD_FREQ_RESP_IDX);
}

static void fm_irq_afjump_rd_freq_resp(struct fmdev *fmdev)
{
    struct sk_buff *skb;
    u16 read_freq;
    u32 curr_freq, jumped_freq;

    if (check_cmdresp_status(fmdev, &skb))
        return;

    /* Skip header info and copy only response data */
    skb_pull(skb, sizeof(struct fm_event_msg_hdr));
    memcpy(&read_freq, skb->data, sizeof(read_freq));
    read_freq = be16_to_cpu(read_freq);
    curr_freq = fmdev->rx.region.bot_freq + ((u32)read_freq * FM_FREQ_MUL);

    jumped_freq = fmdev->rx.stat_info.af_cache[fmdev->rx.afjump_idx];

    /* If the frequency was changed the jump succeeded */
    if ((curr_freq != fmdev->rx.freq_before_jump) && (curr_freq == jumped_freq)) {
        fmdbg("Successfully switched to alternate freq %d\n", curr_freq);
        fmdev->rx.freq = curr_freq;
        fm_rx_reset_rds_cache(fmdev);

        /* AF feature is on, enable low level RSSI interrupt */
        if (fmdev->rx.af_mode == FM_RX_RDS_AF_SWITCH_MODE_ON)
            fmdev->irq_info.mask |= FM_LEV_EVENT;

        fmdev->irq_info.stage = FM_LOW_RSSI_FINISH_IDX;
    } else {        /* jump to the next freq in the AF list */
        fmdev->rx.afjump_idx++;

        /* If we reached the end of the list - stop searching */
        if (fmdev->rx.afjump_idx >= fmdev->rx.stat_info.afcache_size) {
            fmdbg("AF switch processing failed\n");
            fmdev->irq_info.stage = FM_LOW_RSSI_FINISH_IDX;
        } else {    /* AF List is not over - try next one */

            fmdbg("Trying next freq in AF cache\n");
            fmdev->irq_info.stage = FM_AF_JUMP_SETPI_IDX;
        }
    }
    fm_irq_call(fmdev);
}

static void fm_irq_handle_low_rssi_finish(struct fmdev *fmdev)
{
    fm_irq_call_stage(fmdev, FM_SEND_INTMSK_CMD_IDX);
}

static void fm_irq_send_intmsk_cmd(struct fmdev *fmdev)
{
    u16 payload;

    /* Re-enable FM interrupts */
    payload = fmdev->irq_info.mask;

    if (!fm_send_cmd(fmdev, INT_MASK_SET, REG_WR, &payload,
            sizeof(payload), NULL))
        fm_irq_timeout_stage(fmdev, FM_HANDLE_INTMSK_CMD_RESP_IDX);
}

static void fm_irq_handle_intmsk_cmd_resp(struct fmdev *fmdev)
{
    struct sk_buff *skb;

    if (check_cmdresp_status(fmdev, &skb))
        return;
    /*
     * This is last function in interrupt table to be executed.
     * So, reset stage index to 0.
     */
    fmdev->irq_info.stage = FM_SEND_FLAG_GETCMD_IDX;

    /* Start processing any pending interrupt */
    if (test_and_clear_bit(FM_INTTASK_SCHEDULE_PENDING, &fmdev->flag))
        fmdev->irq_info.handlers[fmdev->irq_info.stage](fmdev);
    else
        clear_bit(FM_INTTASK_RUNNING, &fmdev->flag);
}

/* Returns availability of RDS data in internel buffer */
int fmc_is_rds_data_available(struct fmdev *fmdev, struct file *file,
                struct poll_table_struct *pts)
{
    poll_wait(file, &fmdev->rx.rds.read_queue, pts);
    if (fmdev->rx.rds.rd_idx != fmdev->rx.rds.wr_idx)
        return 0;

    return -EAGAIN;
}

/* Copies RDS data from internal buffer to user buffer */
int fmc_transfer_rds_from_internal_buff(struct fmdev *fmdev, struct file *file,
        u8 __user *buf, size_t count)
{
    u32 block_count;
    unsigned long flags;
    int ret;

    if (fmdev->rx.rds.wr_idx == fmdev->rx.rds.rd_idx) {
        if (file->f_flags & O_NONBLOCK)
            return -EWOULDBLOCK;

        ret = wait_event_interruptible(fmdev->rx.rds.read_queue,
                (fmdev->rx.rds.wr_idx != fmdev->rx.rds.rd_idx));
        if (ret)
            return -EINTR;
    }

    /* Calculate block count from byte count */
    count /= 3;
    block_count = 0;
    ret = 0;

    spin_lock_irqsave(&fmdev->rds_buff_lock, flags);

    while (block_count < count) {
        if (fmdev->rx.rds.wr_idx == fmdev->rx.rds.rd_idx)
            break;

        if (copy_to_user(buf, &fmdev->rx.rds.buff[fmdev->rx.rds.rd_idx],
                    FM_RDS_BLK_SIZE))
            break;

        fmdev->rx.rds.rd_idx += FM_RDS_BLK_SIZE;
        if (fmdev->rx.rds.rd_idx >= fmdev->rx.rds.buf_size)
            fmdev->rx.rds.rd_idx = 0;

        block_count++;
        buf += FM_RDS_BLK_SIZE;
        ret += FM_RDS_BLK_SIZE;
    }
    spin_unlock_irqrestore(&fmdev->rds_buff_lock, flags);
    return ret;
}

int fmc_set_freq(struct fmdev *fmdev, u32 freq_to_set)
{
    switch (fmdev->curr_fmmode) {
    case FM_MODE_RX:
        return fm_rx_set_freq(fmdev, freq_to_set);

    case FM_MODE_TX:
        return fm_tx_set_freq(fmdev, freq_to_set);

    default:
        return -EINVAL;
    }
}

int fmc_get_freq(struct fmdev *fmdev, u32 *cur_tuned_frq)
{
    if (fmdev->rx.freq == FM_UNDEFINED_FREQ) {
        fmerr("RX frequency is not set\n");
        return -EPERM;
    }
    if (cur_tuned_frq == NULL) {
        fmerr("Invalid memory\n");
        return -ENOMEM;
    }

    switch (fmdev->curr_fmmode) {
    case FM_MODE_RX:
        *cur_tuned_frq = fmdev->rx.freq;
        return 0;

    case FM_MODE_TX:
        *cur_tuned_frq = 0; /* TODO : Change this later */
        return 0;

    default:
        return -EINVAL;
    }

}

int fmc_set_region(struct fmdev *fmdev, u8 region_to_set)
{
    switch (fmdev->curr_fmmode) {
    case FM_MODE_RX:
        return fm_rx_set_region(fmdev, region_to_set);

    case FM_MODE_TX:
        return fm_tx_set_region(fmdev, region_to_set);

    default:
        return -EINVAL;
    }
}

int fmc_set_mute_mode(struct fmdev *fmdev, u8 mute_mode_toset)
{
    switch (fmdev->curr_fmmode) {
    case FM_MODE_RX:
        return fm_rx_set_mute_mode(fmdev, mute_mode_toset);

    case FM_MODE_TX:
        return fm_tx_set_mute_mode(fmdev, mute_mode_toset);

    default:
        return -EINVAL;
    }
}

int fmc_set_stereo_mono(struct fmdev *fmdev, u16 mode)
{
    switch (fmdev->curr_fmmode) {
    case FM_MODE_RX:
        return fm_rx_set_stereo_mono(fmdev, mode);

    case FM_MODE_TX:
        return fm_tx_set_stereo_mono(fmdev, mode);

    default:
        return -EINVAL;
    }
}

int fmc_set_rds_mode(struct fmdev *fmdev, u8 rds_en_dis)
{
    switch (fmdev->curr_fmmode) {
    case FM_MODE_RX:
        return fm_rx_set_rds_mode(fmdev, rds_en_dis);

    case FM_MODE_TX:
        return fm_tx_set_rds_mode(fmdev, rds_en_dis);

    default:
        return -EINVAL;
    }
}

/* Sends power off command to the chip */
static int fm_power_down(struct fmdev *fmdev)
{
    u16 payload;
    int ret;

    if (!test_bit(FM_CORE_READY, &fmdev->flag)) {
        fmerr("FM core is not ready\n");
        return -EPERM;
    }
    if (fmdev->curr_fmmode == FM_MODE_OFF) {
        fmdbg("FM chip is already in OFF state\n");
        return 0;
    }

    payload = 0x0;
    ret = fmc_send_cmd(fmdev, FM_POWER_MODE, REG_WR, &payload,
        sizeof(payload), NULL, NULL);
    if (ret < 0)
        return ret;

    return fmc_release(fmdev);
}

/* Reads init command from FM firmware file and loads to the chip */
static int fm_download_firmware(struct fmdev *fmdev, const u8 *fw_name)
{
    const struct firmware *fw_entry;
    struct bts_header *fw_header;
    struct bts_action *action;
    struct bts_action_delay *delay;
    u8 *fw_data;
    int ret, fw_len, cmd_cnt;

    cmd_cnt = 0;
    set_bit(FM_FW_DW_INPROGRESS, &fmdev->flag);

    ret = request_firmware(&fw_entry, fw_name,
                &fmdev->radio_dev->dev);
    if (ret < 0) {
        fmerr("Unable to read firmware(%s) content\n", fw_name);
        return ret;
    }
    fmdbg("Firmware(%s) length : %d bytes\n", fw_name, fw_entry->size);

    fw_data = (void *)fw_entry->data;
    fw_len = fw_entry->size;

    fw_header = (struct bts_header *)fw_data;
    if (fw_header->magic != FM_FW_FILE_HEADER_MAGIC) {
        fmerr("%s not a legal TI firmware file\n", fw_name);
        ret = -EINVAL;
        goto rel_fw;
    }
    fmdbg("FW(%s) magic number : 0x%x\n", fw_name, fw_header->magic);

    /* Skip file header info , we already verified it */
    fw_data += sizeof(struct bts_header);
    fw_len -= sizeof(struct bts_header);

    while (fw_data && fw_len > 0) {
        action = (struct bts_action *)fw_data;

        switch (action->type) {
        case ACTION_SEND_COMMAND:   /* Send */
            if (fmc_send_cmd(fmdev, 0, 0, action->data,
                        action->size, NULL, NULL))
                goto rel_fw;

            cmd_cnt++;
            break;

        case ACTION_DELAY:  /* Delay */
            delay = (struct bts_action_delay *)action->data;
            mdelay(delay->msec);
            break;
        }

        fw_data += (sizeof(struct bts_action) + (action->size));
        fw_len -= (sizeof(struct bts_action) + (action->size));
    }
    fmdbg("Firmware commands(%d) loaded to chip\n", cmd_cnt);
rel_fw:
    release_firmware(fw_entry);
    clear_bit(FM_FW_DW_INPROGRESS, &fmdev->flag);

    return ret;
}

/* Loads default RX configuration to the chip */
static int load_default_rx_configuration(struct fmdev *fmdev)
{
    int ret;

    ret = fm_rx_set_volume(fmdev, FM_DEFAULT_RX_VOLUME);
    if (ret < 0)
        return ret;

    return fm_rx_set_rssi_threshold(fmdev, FM_DEFAULT_RSSI_THRESHOLD);
}

/* Does FM power on sequence */
static int fm_power_up(struct fmdev *fmdev, u8 mode)
{
    u16 payload, asic_id, asic_ver;
    int resp_len, ret;
    u8 fw_name[50];

    if (mode >= FM_MODE_ENTRY_MAX) {
        fmerr("Invalid firmware download option\n");
        return -EINVAL;
    }

    /*
     * Initialize FM common module. FM GPIO toggling is
     * taken care in Shared Transport driver.
     */
    ret = fmc_prepare(fmdev);
    if (ret < 0) {
        fmerr("Unable to prepare FM Common\n");
        return ret;
    }

    payload = FM_ENABLE;
    if (fmc_send_cmd(fmdev, FM_POWER_MODE, REG_WR, &payload,
            sizeof(payload), NULL, NULL))
        goto rel;

    /* Allow the chip to settle down in Channel-8 mode */
    msleep(20);

    if (fmc_send_cmd(fmdev, ASIC_ID_GET, REG_RD, NULL,
            sizeof(asic_id), &asic_id, &resp_len))
        goto rel;

    if (fmc_send_cmd(fmdev, ASIC_VER_GET, REG_RD, NULL,
            sizeof(asic_ver), &asic_ver, &resp_len))
        goto rel;

    fmdbg("ASIC ID: 0x%x , ASIC Version: %d\n",
        be16_to_cpu(asic_id), be16_to_cpu(asic_ver));

    sprintf(fw_name, "%s_%x.%d.bts", FM_FMC_FW_FILE_START,
        be16_to_cpu(asic_id), be16_to_cpu(asic_ver));

    ret = fm_download_firmware(fmdev, fw_name);
    if (ret < 0) {
        fmdbg("Failed to download firmware file %s\n", fw_name);
        goto rel;
    }
    sprintf(fw_name, "%s_%x.%d.bts", (mode == FM_MODE_RX) ?
            FM_RX_FW_FILE_START : FM_TX_FW_FILE_START,
            be16_to_cpu(asic_id), be16_to_cpu(asic_ver));

    ret = fm_download_firmware(fmdev, fw_name);
    if (ret < 0) {
        fmdbg("Failed to download firmware file %s\n", fw_name);
        goto rel;
    } else
        return ret;
rel:
    return fmc_release(fmdev);
}

/* Set FM Modes(TX, RX, OFF) */
int fmc_set_mode(struct fmdev *fmdev, u8 fm_mode)
{
    int ret = 0;

    if (fm_mode >= FM_MODE_ENTRY_MAX) {
        fmerr("Invalid FM mode\n");
        return -EINVAL;
    }
    if (fmdev->curr_fmmode == fm_mode) {
        fmdbg("Already fm is in mode(%d)\n", fm_mode);
        return ret;
    }

    switch (fm_mode) {
    case FM_MODE_OFF:   /* OFF Mode */
        ret = fm_power_down(fmdev);
        if (ret < 0) {
            fmerr("Failed to set OFF mode\n");
            return ret;
        }
        break;

    case FM_MODE_TX:    /* TX Mode */
    case FM_MODE_RX:    /* RX Mode */
        /* Power down before switching to TX or RX mode */
        if (fmdev->curr_fmmode != FM_MODE_OFF) {
            ret = fm_power_down(fmdev);
            if (ret < 0) {
                fmerr("Failed to set OFF mode\n");
                return ret;
            }
            msleep(30);
        }
        ret = fm_power_up(fmdev, fm_mode);
        if (ret < 0) {
            fmerr("Failed to load firmware\n");
            return ret;
        }
    }
    fmdev->curr_fmmode = fm_mode;

    /* Set default configuration */
    if (fmdev->curr_fmmode == FM_MODE_RX) {
        fmdbg("Loading default rx configuration..\n");
        ret = load_default_rx_configuration(fmdev);
        if (ret < 0)
            fmerr("Failed to load default values\n");
    }

    return ret;
}

/* Returns current FM mode (TX, RX, OFF) */
int fmc_get_mode(struct fmdev *fmdev, u8 *fmmode)
{
    if (!test_bit(FM_CORE_READY, &fmdev->flag)) {
        fmerr("FM core is not ready\n");
        return -EPERM;
    }
    if (fmmode == NULL) {
        fmerr("Invalid memory\n");
        return -ENOMEM;
    }

    *fmmode = fmdev->curr_fmmode;
    return 0;
}

/* Called by ST layer when FM packet is available */
static long fm_st_receive(void *arg, struct sk_buff *skb)
{
    struct fmdev *fmdev;

    fmdev = (struct fmdev *)arg;

    if (skb == NULL) {
        fmerr("Invalid SKB received from ST\n");
        return -EFAULT;
    }

    if (skb->cb[0] != FM_PKT_LOGICAL_CHAN_NUMBER) {
        fmerr("Received SKB (%p) is not FM Channel 8 pkt\n", skb);
        return -EINVAL;
    }

    memcpy(skb_push(skb, 1), &skb->cb[0], 1);
    skb_queue_tail(&fmdev->rx_q, skb);
    tasklet_schedule(&fmdev->rx_task);

    return 0;
}

/*
 * Called by ST layer to indicate protocol registration completion
 * status.
 */
static void fm_st_reg_comp_cb(void *arg, char data)
{
    struct fmdev *fmdev;

    fmdev = (struct fmdev *)arg;
    fmdev->streg_cbdata = data;
    complete(&wait_for_fmdrv_reg_comp);
}

/*
 * This function will be called from FM V4L2 open function.
 * Register with ST driver and initialize driver data.
 */
int fmc_prepare(struct fmdev *fmdev)
{
    static struct st_proto_s fm_st_proto;
    int ret;

    if (test_bit(FM_CORE_READY, &fmdev->flag)) {
        fmdbg("FM Core is already up\n");
        return 0;
    }

    memset(&fm_st_proto, 0, sizeof(fm_st_proto));
    fm_st_proto.recv = fm_st_receive;
    fm_st_proto.match_packet = NULL;
    fm_st_proto.reg_complete_cb = fm_st_reg_comp_cb;
    fm_st_proto.write = NULL; /* TI ST driver will fill write pointer */
    fm_st_proto.priv_data = fmdev;
    fm_st_proto.chnl_id = 0x08;
    fm_st_proto.max_frame_size = 0xff;
    fm_st_proto.hdr_len = 1;
    fm_st_proto.offset_len_in_hdr = 0;
    fm_st_proto.len_size = 1;
    fm_st_proto.reserve = 1;

    ret = st_register(&fm_st_proto);
    if (ret == -EINPROGRESS) {
        init_completion(&wait_for_fmdrv_reg_comp);
        fmdev->streg_cbdata = -EINPROGRESS;
        fmdbg("%s waiting for ST reg completion signal\n", __func__);

        if (!wait_for_completion_timeout(&wait_for_fmdrv_reg_comp,
                         FM_ST_REG_TIMEOUT)) {
            fmerr("Timeout(%d sec), didn't get reg "
                    "completion signal from ST\n",
                    jiffies_to_msecs(FM_ST_REG_TIMEOUT) / 1000);
            return -ETIMEDOUT;
        }
        if (fmdev->streg_cbdata != 0) {
            fmerr("ST reg comp CB called with error "
                    "status %d\n", fmdev->streg_cbdata);
            return -EAGAIN;
        }

        ret = 0;
    } else if (ret == -1) {
        fmerr("st_register failed %d\n", ret);
        return -EAGAIN;
    }

    if (fm_st_proto.write != NULL) {
        g_st_write = fm_st_proto.write;
    } else {
        fmerr("Failed to get ST write func pointer\n");
        ret = st_unregister(&fm_st_proto);
        if (ret < 0)
            fmerr("st_unregister failed %d\n", ret);
        return -EAGAIN;
    }

    spin_lock_init(&fmdev->rds_buff_lock);
    spin_lock_init(&fmdev->resp_skb_lock);

    /* Initialize TX queue and TX tasklet */
    skb_queue_head_init(&fmdev->tx_q);
    tasklet_init(&fmdev->tx_task, send_tasklet, (unsigned long)fmdev);

    /* Initialize RX Queue and RX tasklet */
    skb_queue_head_init(&fmdev->rx_q);
    tasklet_init(&fmdev->rx_task, recv_tasklet, (unsigned long)fmdev);

    fmdev->irq_info.stage = 0;
    atomic_set(&fmdev->tx_cnt, 1);
    fmdev->resp_comp = NULL;

    init_timer(&fmdev->irq_info.timer);
    fmdev->irq_info.timer.function = &int_timeout_handler;
    fmdev->irq_info.timer.data = (unsigned long)fmdev;
    /*TODO: add FM_STIC_EVENT later */
    fmdev->irq_info.mask = FM_MAL_EVENT;

    /* Region info */
    memcpy(&fmdev->rx.region, &region_configs[default_radio_region],
            sizeof(struct region_info));

    fmdev->rx.mute_mode = FM_MUTE_OFF;
    fmdev->rx.rf_depend_mute = FM_RX_RF_DEPENDENT_MUTE_OFF;
    fmdev->rx.rds.flag = FM_RDS_DISABLE;
    fmdev->rx.freq = FM_UNDEFINED_FREQ;
    fmdev->rx.rds_mode = FM_RDS_SYSTEM_RDS;
    fmdev->rx.af_mode = FM_RX_RDS_AF_SWITCH_MODE_OFF;
    fmdev->irq_info.retry = 0;

    fm_rx_reset_rds_cache(fmdev);
    init_waitqueue_head(&fmdev->rx.rds.read_queue);

    fm_rx_reset_station_info(fmdev);
    set_bit(FM_CORE_READY, &fmdev->flag);

    return ret;
}

/*
 * This function will be called from FM V4L2 release function.
 * Unregister from ST driver.
 */
int fmc_release(struct fmdev *fmdev)
{
    static struct st_proto_s fm_st_proto;
    int ret;

    if (!test_bit(FM_CORE_READY, &fmdev->flag)) {
        fmdbg("FM Core is already down\n");
        return 0;
    }
    /* Service pending read */
    wake_up_interruptible(&fmdev->rx.rds.read_queue);

    tasklet_kill(&fmdev->tx_task);
    tasklet_kill(&fmdev->rx_task);

    skb_queue_purge(&fmdev->tx_q);
    skb_queue_purge(&fmdev->rx_q);

    fmdev->resp_comp = NULL;
    fmdev->rx.freq = 0;

    memset(&fm_st_proto, 0, sizeof(fm_st_proto));
    fm_st_proto.chnl_id = 0x08;

    ret = st_unregister(&fm_st_proto);

    if (ret < 0)
        fmerr("Failed to de-register FM from ST %d\n", ret);
    else
        fmdbg("Successfully unregistered from ST\n");

    clear_bit(FM_CORE_READY, &fmdev->flag);
    return ret;
}

/*
 * Module init function. Ask FM V4L module to register video device.
 * Allocate memory for FM driver context and RX RDS buffer.
 */
static int __init fm_drv_init(void)
{
    struct fmdev *fmdev = NULL;
    int ret = -ENOMEM;

    fmdbg("FM driver version %s\n", FM_DRV_VERSION);

    fmdev = kzalloc(sizeof(struct fmdev), GFP_KERNEL);
    if (NULL == fmdev) {
        fmerr("Can't allocate operation structure memory\n");
        return ret;
    }
    fmdev->rx.rds.buf_size = default_rds_buf * FM_RDS_BLK_SIZE;
    fmdev->rx.rds.buff = kzalloc(fmdev->rx.rds.buf_size, GFP_KERNEL);
    if (NULL == fmdev->rx.rds.buff) {
        fmerr("Can't allocate rds ring buffer\n");
        goto rel_dev;
    }

    ret = fm_v4l2_init_video_device(fmdev, radio_nr);
    if (ret < 0)
        goto rel_rdsbuf;

    fmdev->irq_info.handlers = int_handler_table;
    fmdev->curr_fmmode = FM_MODE_OFF;
    fmdev->tx_data.pwr_lvl = FM_PWR_LVL_DEF;
    fmdev->tx_data.preemph = FM_TX_PREEMPH_50US;
    return ret;

rel_rdsbuf:
    kfree(fmdev->rx.rds.buff);
rel_dev:
    kfree(fmdev);

    return ret;
}

/* Module exit function. Ask FM V4L module to unregister video device */
static void __exit fm_drv_exit(void)
{
    struct fmdev *fmdev = NULL;

    fmdev = fm_v4l2_deinit_video_device();
    if (fmdev != NULL) {
        kfree(fmdev->rx.rds.buff);
        kfree(fmdev);
    }
}

module_init(fm_drv_init);
module_exit(fm_drv_exit);

/* ------------- Module Info ------------- */
MODULE_AUTHOR("Manjunatha Halli <[email protected]>");
MODULE_DESCRIPTION("FM Driver for TI's Connectivity chip. " FM_DRV_VERSION);
MODULE_VERSION(FM_DRV_VERSION);
MODULE_LICENSE("GPL");