cx25821: sanitize cx25821_openfile_audio() a bit...

static 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;

		}

	char *p = (void *)dev->_audiodata_buf_virt_addr;

	struct file *file;

	loff_t offset;

	int i, j;

		if (!myfile->f_op->read) {

			pr_err("%s(): File has no READ operations registered!\n",

				__func__);

			filp_close(myfile, NULL);

			return -EIO;

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

	if (IS_ERR(file)) {

		pr_err("%s(): ERROR opening file(%s) with errno = %ld!\n",

			__func__, dev->_audiofilename, PTR_ERR(file));

		return PTR_ERR(file);

	}

		pos = myfile->f_pos;

		old_fs = get_fs();

		set_fs(KERNEL_DS);

		for (j = 0; j < NUM_AUDIO_FRAMES; j++) {

	for (j = 0, offset = 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);

				}

			char buf[AUDIO_LINE_SIZE];

			int n = kernel_read(file, offset, buf,

						AUDIO_LINE_SIZE);

				offset += vfs_read_retval;

				if (vfs_read_retval < line_size) {

			if (n < AUDIO_LINE_SIZE) {

				pr_info("Done: exit %s() since no more bytes to read from Audio file\n",

					__func__);

					break;

				}

				dev->_audiofile_status = END_OF_FILE;

				fput(file);

				return 0;

			}

			if (i > 0)

				dev->_audioframe_count++;

			if (p)

				memcpy(p + offset, buf, n);

			if (vfs_read_retval < line_size)

				break;

			offset += n;

		}

		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);

		dev->_audioframe_count++;

	}

	dev->_audiofile_status = IN_PROGRESS;

	fput(file);

	return 0;

}