static int __init dsp_init()

in mISDN/dsp_core.c [1115:1204]

• 79 lines of code
• 14 McCabe index (conditional complexity)

static int __init dsp_init(void)
{
	int err;
	int tics;

	printk(KERN_INFO "DSP module %s\n", mISDN_dsp_revision);

	dsp_options = options;
	dsp_debug = debug;

	/* set packet size */
	dsp_poll = poll;
	if (dsp_poll) {
		if (dsp_poll > MAX_POLL) {
			printk(KERN_ERR "%s: Wrong poll value (%d), use %d "
			       "maximum.\n", __func__, poll, MAX_POLL);
			err = -EINVAL;
			return err;
		}
		if (dsp_poll < 8) {
			printk(KERN_ERR "%s: Wrong poll value (%d), use 8 "
			       "minimum.\n", __func__, dsp_poll);
			err = -EINVAL;
			return err;
		}
		dsp_tics = poll * HZ / 8000;
		if (dsp_tics * 8000 != poll * HZ) {
			printk(KERN_INFO "mISDN_dsp: Cannot clock every %d "
			       "samples (0,125 ms). It is not a multiple of "
			       "%d HZ.\n", poll, HZ);
			err = -EINVAL;
			return err;
		}
	} else {
		poll = 8;
		while (poll <= MAX_POLL) {
			tics = (poll * HZ) / 8000;
			if (tics * 8000 == poll * HZ) {
				dsp_tics = tics;
				dsp_poll = poll;
				if (poll >= 64)
					break;
			}
			poll++;
		}
	}
	if (dsp_poll == 0) {
		printk(KERN_INFO "mISDN_dsp: There is no multiple of kernel "
		       "clock that equals exactly the duration of 8-256 "
		       "samples. (Choose kernel clock speed like 100, 250, "
		       "300, 1000)\n");
		err = -EINVAL;
		return err;
	}
	printk(KERN_INFO "mISDN_dsp: DSP clocks every %d samples. This equals "
	       "%d jiffies.\n", dsp_poll, dsp_tics);

	/* init conversion tables */
	dsp_audio_generate_law_tables();
	dsp_silence = (dsp_options & DSP_OPT_ULAW) ? 0xff : 0x2a;
	dsp_audio_law_to_s32 = (dsp_options & DSP_OPT_ULAW) ?
		dsp_audio_ulaw_to_s32 : dsp_audio_alaw_to_s32;
	dsp_audio_generate_s2law_table();
	dsp_audio_generate_seven();
	dsp_audio_generate_mix_table();
	if (dsp_options & DSP_OPT_ULAW)
		dsp_audio_generate_ulaw_samples();
	dsp_audio_generate_volume_changes();

	err = dsp_pipeline_module_init();
	if (err) {
		printk(KERN_ERR "mISDN_dsp: Can't initialize pipeline, "
		       "error(%d)\n", err);
		return err;
	}

	err = mISDN_register_Bprotocol(&DSP);
	if (err) {
		printk(KERN_ERR "Can't register %s error(%d)\n", DSP.name, err);
		return err;
	}

	/* set sample timer */
	timer_setup(&dsp_spl_tl, (void *)dsp_cmx_send, 0);
	dsp_spl_tl.expires = jiffies + dsp_tics;
	dsp_spl_jiffies = dsp_spl_tl.expires;
	add_timer(&dsp_spl_tl);

	return 0;
}