cx25821-audio-upstream.c

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/*
 *  Driver for the Conexant CX25821 PCIe bridge
 *
 *  Copyright (C) 2009 Conexant Systems Inc.
 *  Authors  <[email protected]>, <[email protected]>
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  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., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include "cx25821-video.h"
#include "cx25821-audio-upstream.h"

#include <linux/fs.h>
#include <linux/errno.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/syscalls.h>
#include <linux/file.h>
#include <linux/fcntl.h>
#include <linux/delay.h>
#include <linux/slab.h>
#include <linux/uaccess.h>

MODULE_DESCRIPTION("v4l2 driver module for cx25821 based TV cards");
MODULE_AUTHOR("Hiep Huynh <[email protected]>");
MODULE_LICENSE("GPL");

static int _intr_msk = FLD_AUD_SRC_RISCI1 | FLD_AUD_SRC_OF |
            FLD_AUD_SRC_SYNC | FLD_AUD_SRC_OPC_ERR;

int cx25821_sram_channel_setup_upstream_audio(struct cx25821_dev *dev,
                          struct sram_channel *ch,
                          unsigned int bpl, u32 risc)
{
    unsigned int i, lines;
    u32 cdt;

    if (ch->cmds_start == 0) {
        cx_write(ch->ptr1_reg, 0);
        cx_write(ch->ptr2_reg, 0);
        cx_write(ch->cnt2_reg, 0);
        cx_write(ch->cnt1_reg, 0);
        return 0;
    }

    bpl = (bpl + 7) & ~7;   /* alignment */
    cdt = ch->cdt;
    lines = ch->fifo_size / bpl;

    if (lines > 3)
        lines = 3;

    BUG_ON(lines < 2);

    /* write CDT */
    for (i = 0; i < lines; i++) {
        cx_write(cdt + 16 * i, ch->fifo_start + bpl * i);
        cx_write(cdt + 16 * i + 4, 0);
        cx_write(cdt + 16 * i + 8, 0);
        cx_write(cdt + 16 * i + 12, 0);
    }

    /* write CMDS */
    cx_write(ch->cmds_start + 0, risc);

    cx_write(ch->cmds_start + 4, 0);
    cx_write(ch->cmds_start + 8, cdt);
    cx_write(ch->cmds_start + 12, AUDIO_CDT_SIZE_QW);
    cx_write(ch->cmds_start + 16, ch->ctrl_start);

    /* IQ size */
    cx_write(ch->cmds_start + 20, AUDIO_IQ_SIZE_DW);

    for (i = 24; i < 80; i += 4)
        cx_write(ch->cmds_start + i, 0);

    /* fill registers */
    cx_write(ch->ptr1_reg, ch->fifo_start);
    cx_write(ch->ptr2_reg, cdt);
    cx_write(ch->cnt2_reg, AUDIO_CDT_SIZE_QW);
    cx_write(ch->cnt1_reg, AUDIO_CLUSTER_SIZE_QW - 1);

    return 0;
}

static __le32 *cx25821_risc_field_upstream_audio(struct cx25821_dev *dev,
                         __le32 *rp,
                         dma_addr_t databuf_phys_addr,
                         unsigned int bpl,
                         int fifo_enable)
{
    unsigned int line;
    struct sram_channel *sram_ch =
        dev->channels[dev->_audio_upstream_channel].sram_channels;
    int offset = 0;

    /* scan lines */
    for (line = 0; line < LINES_PER_AUDIO_BUFFER; line++) {
        *(rp++) = cpu_to_le32(RISC_READ | RISC_SOL | RISC_EOL | bpl);
        *(rp++) = cpu_to_le32(databuf_phys_addr + offset);
        *(rp++) = cpu_to_le32(0);   /* bits 63-32 */

        /* Check if we need to enable the FIFO
         * after the first 3 lines.
         * For the upstream audio channel,
         * the risc engine will enable the FIFO */
        if (fifo_enable && line == 2) {
            *(rp++) = RISC_WRITECR;
            *(rp++) = sram_ch->dma_ctl;
            *(rp++) = sram_ch->fld_aud_fifo_en;
            *(rp++) = 0x00000020;
        }

        offset += AUDIO_LINE_SIZE;
    }

    return rp;
}

int cx25821_risc_buffer_upstream_audio(struct cx25821_dev *dev,
                       struct pci_dev *pci,
                       unsigned int bpl, unsigned int lines)
{
    __le32 *rp;
    int fifo_enable = 0;
    int frame = 0, i = 0;
    int frame_size = AUDIO_DATA_BUF_SZ;
    int databuf_offset = 0;
    int risc_flag = RISC_CNT_INC;
    dma_addr_t risc_phys_jump_addr;

    /* Virtual address of Risc buffer program */
    rp = dev->_risc_virt_addr;

    /* sync instruction */
    *(rp++) = cpu_to_le32(RISC_RESYNC | AUDIO_SYNC_LINE);

    for (frame = 0; frame < NUM_AUDIO_FRAMES; frame++) {
        databuf_offset = frame_size * frame;

        if (frame == 0) {
            fifo_enable = 1;
            risc_flag = RISC_CNT_RESET;
        } else {
            fifo_enable = 0;
            risc_flag = RISC_CNT_INC;
        }

        /* Calculate physical jump address */
        if ((frame + 1) == NUM_AUDIO_FRAMES) {
            risc_phys_jump_addr =
                dev->_risc_phys_start_addr +
                RISC_SYNC_INSTRUCTION_SIZE;
        } else {
            risc_phys_jump_addr =
                dev->_risc_phys_start_addr +
                RISC_SYNC_INSTRUCTION_SIZE +
                AUDIO_RISC_DMA_BUF_SIZE * (frame + 1);
        }

        rp = cx25821_risc_field_upstream_audio(dev, rp,
                dev->_audiodata_buf_phys_addr + databuf_offset,
                bpl, fifo_enable);

        if (USE_RISC_NOOP_AUDIO) {
            for (i = 0; i < NUM_NO_OPS; i++)
                *(rp++) = cpu_to_le32(RISC_NOOP);
        }

        /* Loop to (Nth)FrameRISC or to Start of Risc program &
         * generate IRQ */
        *(rp++) = cpu_to_le32(RISC_JUMP | RISC_IRQ1 | risc_flag);
        *(rp++) = cpu_to_le32(risc_phys_jump_addr);
        *(rp++) = cpu_to_le32(0);

        /* Recalculate virtual address based on frame index */
        rp = dev->_risc_virt_addr + RISC_SYNC_INSTRUCTION_SIZE / 4 +
            (AUDIO_RISC_DMA_BUF_SIZE * (frame + 1) / 4);
    }

    return 0;
}

void cx25821_free_memory_audio(struct cx25821_dev *dev)
{
    if (dev->_risc_virt_addr) {
        pci_free_consistent(dev->pci, dev->_audiorisc_size,
                    dev->_risc_virt_addr, dev->_risc_phys_addr);
        dev->_risc_virt_addr = NULL;
    }

    if (dev->_audiodata_buf_virt_addr) {
        pci_free_consistent(dev->pci, dev->_audiodata_buf_size,
                    dev->_audiodata_buf_virt_addr,
                    dev->_audiodata_buf_phys_addr);
        dev->_audiodata_buf_virt_addr = NULL;
    }
}

void cx25821_stop_upstream_audio(struct cx25821_dev *dev)
{
    struct sram_channel *sram_ch =
        dev->channels[AUDIO_UPSTREAM_SRAM_CHANNEL_B].sram_channels;
    u32 tmp = 0;

    if (!dev->_audio_is_running) {
        printk(KERN_DEBUG
               pr_fmt("No audio file is currently running so return!\n"));
        return;
    }
    /* Disable RISC interrupts */
    cx_write(sram_ch->int_msk, 0);

    /* Turn OFF risc and fifo enable in AUD_DMA_CNTRL */
    tmp = cx_read(sram_ch->dma_ctl);
    cx_write(sram_ch->dma_ctl,
         tmp & ~(sram_ch->fld_aud_fifo_en | sram_ch->fld_aud_risc_en));

    /* Clear data buffer memory */
    if (dev->_audiodata_buf_virt_addr)
        memset(dev->_audiodata_buf_virt_addr, 0,
               dev->_audiodata_buf_size);

    dev->_audio_is_running = 0;
    dev->_is_first_audio_frame = 0;
    dev->_audioframe_count = 0;
    dev->_audiofile_status = END_OF_FILE;

    kfree(dev->_irq_audio_queues);
    dev->_irq_audio_queues = NULL;

    kfree(dev->_audiofilename);
}

void cx25821_free_mem_upstream_audio(struct cx25821_dev *dev)
{
    if (dev->_audio_is_running)
        cx25821_stop_upstream_audio(dev);

    cx25821_free_memory_audio(dev);
}

int cx25821_get_audio_data(struct cx25821_dev *dev,
               struct sram_channel *sram_ch)
{
    struct file *myfile;
    int frame_index_temp = dev->_audioframe_index;
    int i = 0;
    int line_size = AUDIO_LINE_SIZE;
    int frame_size = AUDIO_DATA_BUF_SZ;
    int frame_offset = frame_size * frame_index_temp;
    ssize_t vfs_read_retval = 0;
    char mybuf[line_size];
    loff_t file_offset = dev->_audioframe_count * frame_size;
    loff_t pos;
    mm_segment_t old_fs;

    if (dev->_audiofile_status == END_OF_FILE)
        return 0;

    myfile = filp_open(dev->_audiofilename, O_RDONLY | O_LARGEFILE, 0);

    if (IS_ERR(myfile)) {
        const int open_errno = -PTR_ERR(myfile);
        pr_err("%s(): ERROR opening file(%s) with errno = %d!\n",
               __func__, dev->_audiofilename, open_errno);
        return PTR_ERR(myfile);
    } else {
        if (!(myfile->f_op)) {
            pr_err("%s(): File has no file operations registered!\n",
                __func__);
            filp_close(myfile, NULL);
            return -EIO;
        }

        if (!myfile->f_op->read) {
            pr_err("%s(): File has no READ operations registered!\n",
                __func__);
            filp_close(myfile, NULL);
            return -EIO;
        }

        pos = myfile->f_pos;
        old_fs = get_fs();
        set_fs(KERNEL_DS);

        for (i = 0; i < dev->_audio_lines_count; i++) {
            pos = file_offset;

            vfs_read_retval = vfs_read(myfile, mybuf, line_size,
                                    &pos);

            if (vfs_read_retval > 0 && vfs_read_retval == line_size
                && dev->_audiodata_buf_virt_addr != NULL) {
                memcpy((void *)(dev->_audiodata_buf_virt_addr +
                        frame_offset / 4), mybuf,
                    vfs_read_retval);
            }

            file_offset += vfs_read_retval;
            frame_offset += vfs_read_retval;

            if (vfs_read_retval < line_size) {
                pr_info("Done: exit %s() since no more bytes to read from Audio file\n",
                    __func__);
                break;
            }
        }

        if (i > 0)
            dev->_audioframe_count++;

        dev->_audiofile_status = (vfs_read_retval == line_size) ?
                        IN_PROGRESS : END_OF_FILE;

        set_fs(old_fs);
        filp_close(myfile, NULL);
    }

    return 0;
}

static void cx25821_audioups_handler(struct work_struct *work)
{
    struct cx25821_dev *dev = container_of(work, struct cx25821_dev,
            _audio_work_entry);

    if (!dev) {
        pr_err("ERROR %s(): since container_of(work_struct) FAILED!\n",
            __func__);
        return;
    }

    cx25821_get_audio_data(dev, dev->channels[dev->_audio_upstream_channel].
            sram_channels);
}

int cx25821_openfile_audio(struct cx25821_dev *dev,
               struct sram_channel *sram_ch)
{
    struct file *myfile;
    int i = 0, j = 0;
    int line_size = AUDIO_LINE_SIZE;
    ssize_t vfs_read_retval = 0;
    char mybuf[line_size];
    loff_t pos;
    loff_t offset = (unsigned long)0;
    mm_segment_t old_fs;

    myfile = filp_open(dev->_audiofilename, O_RDONLY | O_LARGEFILE, 0);

    if (IS_ERR(myfile)) {
        const int open_errno = -PTR_ERR(myfile);
        pr_err("%s(): ERROR opening file(%s) with errno = %d!\n",
            __func__, dev->_audiofilename, open_errno);
        return PTR_ERR(myfile);
    } else {
        if (!(myfile->f_op)) {
            pr_err("%s(): File has no file operations registered!\n",
                __func__);
            filp_close(myfile, NULL);
            return -EIO;
        }

        if (!myfile->f_op->read) {
            pr_err("%s(): File has no READ operations registered!\n",
                __func__);
            filp_close(myfile, NULL);
            return -EIO;
        }

        pos = myfile->f_pos;
        old_fs = get_fs();
        set_fs(KERNEL_DS);

        for (j = 0; j < NUM_AUDIO_FRAMES; j++) {
            for (i = 0; i < dev->_audio_lines_count; i++) {
                pos = offset;

                vfs_read_retval = vfs_read(myfile, mybuf,
                        line_size, &pos);

                if (vfs_read_retval > 0 &&
                    vfs_read_retval == line_size &&
                    dev->_audiodata_buf_virt_addr != NULL) {
                    memcpy((void *)(dev->
                            _audiodata_buf_virt_addr
                            + offset / 4), mybuf,
                           vfs_read_retval);
                }

                offset += vfs_read_retval;

                if (vfs_read_retval < line_size) {
                    pr_info("Done: exit %s() since no more bytes to read from Audio file\n",
                        __func__);
                    break;
                }
            }

            if (i > 0)
                dev->_audioframe_count++;

            if (vfs_read_retval < line_size)
                break;
        }

        dev->_audiofile_status = (vfs_read_retval == line_size) ?
                        IN_PROGRESS : END_OF_FILE;

        set_fs(old_fs);
        myfile->f_pos = 0;
        filp_close(myfile, NULL);
    }

    return 0;
}

static int cx25821_audio_upstream_buffer_prepare(struct cx25821_dev *dev,
                         struct sram_channel *sram_ch,
                         int bpl)
{
    int ret = 0;
    dma_addr_t dma_addr;
    dma_addr_t data_dma_addr;

    cx25821_free_memory_audio(dev);

    dev->_risc_virt_addr = pci_alloc_consistent(dev->pci,
            dev->audio_upstream_riscbuf_size, &dma_addr);
    dev->_risc_virt_start_addr = dev->_risc_virt_addr;
    dev->_risc_phys_start_addr = dma_addr;
    dev->_risc_phys_addr = dma_addr;
    dev->_audiorisc_size = dev->audio_upstream_riscbuf_size;

    if (!dev->_risc_virt_addr) {
        printk(KERN_DEBUG
            pr_fmt("ERROR: pci_alloc_consistent() FAILED to allocate memory for RISC program! Returning\n"));
        return -ENOMEM;
    }
    /* Clear out memory at address */
    memset(dev->_risc_virt_addr, 0, dev->_audiorisc_size);

    /* For Audio Data buffer allocation */
    dev->_audiodata_buf_virt_addr = pci_alloc_consistent(dev->pci,
            dev->audio_upstream_databuf_size, &data_dma_addr);
    dev->_audiodata_buf_phys_addr = data_dma_addr;
    dev->_audiodata_buf_size = dev->audio_upstream_databuf_size;

    if (!dev->_audiodata_buf_virt_addr) {
        printk(KERN_DEBUG
            pr_fmt("ERROR: pci_alloc_consistent() FAILED to allocate memory for data buffer! Returning\n"));
        return -ENOMEM;
    }
    /* Clear out memory at address */
    memset(dev->_audiodata_buf_virt_addr, 0, dev->_audiodata_buf_size);

    ret = cx25821_openfile_audio(dev, sram_ch);
    if (ret < 0)
        return ret;

    /* Creating RISC programs */
    ret = cx25821_risc_buffer_upstream_audio(dev, dev->pci, bpl,
                        dev->_audio_lines_count);
    if (ret < 0) {
        printk(KERN_DEBUG
            pr_fmt("ERROR creating audio upstream RISC programs!\n"));
        goto error;
    }

    return 0;

error:
    return ret;
}

int cx25821_audio_upstream_irq(struct cx25821_dev *dev, int chan_num,
                   u32 status)
{
    int i = 0;
    u32 int_msk_tmp;
    struct sram_channel *channel = dev->channels[chan_num].sram_channels;
    dma_addr_t risc_phys_jump_addr;
    __le32 *rp;

    if (status & FLD_AUD_SRC_RISCI1) {
        /* Get interrupt_index of the program that interrupted */
        u32 prog_cnt = cx_read(channel->gpcnt);

        /* Since we've identified our IRQ, clear our bits from the
         * interrupt mask and interrupt status registers */
        cx_write(channel->int_msk, 0);
        cx_write(channel->int_stat, cx_read(channel->int_stat));

        spin_lock(&dev->slock);

        while (prog_cnt != dev->_last_index_irq) {
            /* Update _last_index_irq */
            if (dev->_last_index_irq < (NUMBER_OF_PROGRAMS - 1))
                dev->_last_index_irq++;
            else
                dev->_last_index_irq = 0;

            dev->_audioframe_index = dev->_last_index_irq;

            queue_work(dev->_irq_audio_queues,
                   &dev->_audio_work_entry);
        }

        if (dev->_is_first_audio_frame) {
            dev->_is_first_audio_frame = 0;

            if (dev->_risc_virt_start_addr != NULL) {
                risc_phys_jump_addr =
                    dev->_risc_phys_start_addr +
                    RISC_SYNC_INSTRUCTION_SIZE +
                    AUDIO_RISC_DMA_BUF_SIZE;

                rp = cx25821_risc_field_upstream_audio(dev,
                        dev->_risc_virt_start_addr + 1,
                        dev->_audiodata_buf_phys_addr,
                        AUDIO_LINE_SIZE, FIFO_DISABLE);

                if (USE_RISC_NOOP_AUDIO) {
                    for (i = 0; i < NUM_NO_OPS; i++) {
                        *(rp++) =
                            cpu_to_le32(RISC_NOOP);
                    }
                }
                /* Jump to 2nd Audio Frame */
                *(rp++) = cpu_to_le32(RISC_JUMP | RISC_IRQ1 |
                        RISC_CNT_RESET);
                *(rp++) = cpu_to_le32(risc_phys_jump_addr);
                *(rp++) = cpu_to_le32(0);
            }
        }

        spin_unlock(&dev->slock);
    } else {
        if (status & FLD_AUD_SRC_OF)
            pr_warn("%s(): Audio Received Overflow Error Interrupt!\n",
                __func__);

        if (status & FLD_AUD_SRC_SYNC)
            pr_warn("%s(): Audio Received Sync Error Interrupt!\n",
                __func__);

        if (status & FLD_AUD_SRC_OPC_ERR)
            pr_warn("%s(): Audio Received OpCode Error Interrupt!\n",
                __func__);

        /* Read and write back the interrupt status register to clear
         * our bits */
        cx_write(channel->int_stat, cx_read(channel->int_stat));
    }

    if (dev->_audiofile_status == END_OF_FILE) {
        pr_warn("EOF Channel Audio Framecount = %d\n",
            dev->_audioframe_count);
        return -1;
    }
    /* ElSE, set the interrupt mask register, re-enable irq. */
    int_msk_tmp = cx_read(channel->int_msk);
    cx_write(channel->int_msk, int_msk_tmp |= _intr_msk);

    return 0;
}

static irqreturn_t cx25821_upstream_irq_audio(int irq, void *dev_id)
{
    struct cx25821_dev *dev = dev_id;
    u32 audio_status;
    int handled = 0;
    struct sram_channel *sram_ch;

    if (!dev)
        return -1;

    sram_ch = dev->channels[dev->_audio_upstream_channel].sram_channels;

    audio_status = cx_read(sram_ch->int_stat);

    /* Only deal with our interrupt */
    if (audio_status) {
        handled = cx25821_audio_upstream_irq(dev,
                dev->_audio_upstream_channel, audio_status);
    }

    if (handled < 0)
        cx25821_stop_upstream_audio(dev);
    else
        handled += handled;

    return IRQ_RETVAL(handled);
}

static void cx25821_wait_fifo_enable(struct cx25821_dev *dev,
                     struct sram_channel *sram_ch)
{
    int count = 0;
    u32 tmp;

    do {
        /* Wait 10 microsecond before checking to see if the FIFO is
         * turned ON. */
        udelay(10);

        tmp = cx_read(sram_ch->dma_ctl);

        /* 10 millisecond timeout */
        if (count++ > 1000) {
            pr_err("ERROR: %s() fifo is NOT turned on. Timeout!\n",
                __func__);
            return;
        }

    } while (!(tmp & sram_ch->fld_aud_fifo_en));

}

int cx25821_start_audio_dma_upstream(struct cx25821_dev *dev,
                     struct sram_channel *sram_ch)
{
    u32 tmp = 0;
    int err = 0;

    /* Set the physical start address of the RISC program in the initial
     * program counter(IPC) member of the CMDS. */
    cx_write(sram_ch->cmds_start + 0, dev->_risc_phys_addr);
    /* Risc IPC High 64 bits 63-32 */
    cx_write(sram_ch->cmds_start + 4, 0);

    /* reset counter */
    cx_write(sram_ch->gpcnt_ctl, 3);

    /* Set the line length       (It looks like we do not need to set the
     * line length) */
    cx_write(sram_ch->aud_length, AUDIO_LINE_SIZE & FLD_AUD_DST_LN_LNGTH);

    /* Set the input mode to 16-bit */
    tmp = cx_read(sram_ch->aud_cfg);
    tmp |= FLD_AUD_SRC_ENABLE | FLD_AUD_DST_PK_MODE | FLD_AUD_CLK_ENABLE |
        FLD_AUD_MASTER_MODE | FLD_AUD_CLK_SELECT_PLL_D |
        FLD_AUD_SONY_MODE;
    cx_write(sram_ch->aud_cfg, tmp);

    /* Read and write back the interrupt status register to clear it */
    tmp = cx_read(sram_ch->int_stat);
    cx_write(sram_ch->int_stat, tmp);

    /* Clear our bits from the interrupt status register. */
    cx_write(sram_ch->int_stat, _intr_msk);

    /* Set the interrupt mask register, enable irq. */
    cx_set(PCI_INT_MSK, cx_read(PCI_INT_MSK) | (1 << sram_ch->irq_bit));
    tmp = cx_read(sram_ch->int_msk);
    cx_write(sram_ch->int_msk, tmp |= _intr_msk);

    err = request_irq(dev->pci->irq, cx25821_upstream_irq_audio,
            IRQF_SHARED, dev->name, dev);
    if (err < 0) {
        pr_err("%s: can't get upstream IRQ %d\n", dev->name,
                dev->pci->irq);
        goto fail_irq;
    }

    /* Start the DMA  engine */
    tmp = cx_read(sram_ch->dma_ctl);
    cx_set(sram_ch->dma_ctl, tmp | sram_ch->fld_aud_risc_en);

    dev->_audio_is_running = 1;
    dev->_is_first_audio_frame = 1;

    /* The fifo_en bit turns on by the first Risc program */
    cx25821_wait_fifo_enable(dev, sram_ch);

    return 0;

fail_irq:
    cx25821_dev_unregister(dev);
    return err;
}

int cx25821_audio_upstream_init(struct cx25821_dev *dev, int channel_select)
{
    struct sram_channel *sram_ch;
    int retval = 0;
    int err = 0;
    int str_length = 0;

    if (dev->_audio_is_running) {
        pr_warn("Audio Channel is still running so return!\n");
        return 0;
    }

    dev->_audio_upstream_channel = channel_select;
    sram_ch = dev->channels[channel_select].sram_channels;

    /* Work queue */
    INIT_WORK(&dev->_audio_work_entry, cx25821_audioups_handler);
    dev->_irq_audio_queues =
        create_singlethread_workqueue("cx25821_audioworkqueue");

    if (!dev->_irq_audio_queues) {
        printk(KERN_DEBUG
            pr_fmt("ERROR: create_singlethread_workqueue() for Audio FAILED!\n"));
        return -ENOMEM;
    }

    dev->_last_index_irq = 0;
    dev->_audio_is_running = 0;
    dev->_audioframe_count = 0;
    dev->_audiofile_status = RESET_STATUS;
    dev->_audio_lines_count = LINES_PER_AUDIO_BUFFER;
    _line_size = AUDIO_LINE_SIZE;

    if (dev->input_audiofilename) {
        str_length = strlen(dev->input_audiofilename);
        dev->_audiofilename = kmemdup(dev->input_audiofilename,
                          str_length + 1, GFP_KERNEL);

        if (!dev->_audiofilename)
            goto error;

        /* Default if filename is empty string */
        if (strcmp(dev->input_audiofilename, "") == 0)
            dev->_audiofilename = "/root/audioGOOD.wav";
    } else {
        str_length = strlen(_defaultAudioName);
        dev->_audiofilename = kmemdup(_defaultAudioName,
                          str_length + 1, GFP_KERNEL);

        if (!dev->_audiofilename)
            goto error;
    }

    retval = cx25821_sram_channel_setup_upstream_audio(dev, sram_ch,
                            _line_size, 0);

    dev->audio_upstream_riscbuf_size =
        AUDIO_RISC_DMA_BUF_SIZE * NUM_AUDIO_PROGS +
        RISC_SYNC_INSTRUCTION_SIZE;
    dev->audio_upstream_databuf_size = AUDIO_DATA_BUF_SZ * NUM_AUDIO_PROGS;

    /* Allocating buffers and prepare RISC program */
    retval = cx25821_audio_upstream_buffer_prepare(dev, sram_ch,
                            _line_size);
    if (retval < 0) {
        pr_err("%s: Failed to set up Audio upstream buffers!\n",
            dev->name);
        goto error;
    }
    /* Start RISC engine */
    cx25821_start_audio_dma_upstream(dev, sram_ch);

    return 0;

error:
    cx25821_dev_unregister(dev);

    return err;
}