rem: dev->amp_enable(dev, true);
add: ac97_amp_enable(dev, true);
context: ac97_attach(ac97_dev **_dev, codec_reg_read reg_read, codec_reg_write reg_write, void *cookie){	int reg;	ac97_dev *dev;	codec_table *codec;		*_dev = dev = (ac97_dev *) malloc(sizeof(ac97_dev));	dev->cookie = cookie;	dev->reg_read = reg_read;	dev->reg_write = reg_write;	dev->codec_id = (reg_read(cookie, AC97_VENDOR_ID1) << 16) | reg_read(cookie, AC97_VENDOR_ID2);	codec = find_codec_table(dev->codec_id);	dev->codec_info = codec->info;	dev->init = codec->ops->init;	dev->amp_enable = codec->ops->amp_enable;	dev->reg_is_valid = codec->ops->reg_is_valid;	dev->clock = 48000; /* default clock on non-broken motherboards */	/* setup register cache */	for (reg = 0; reg <= 0x7e; reg += 2)		dev->reg_cache[reg] = ac97_reg_uncached_read(dev, reg);	/* reset the codec */		LOG(("codec reset\n"));	ac97_reg_uncached_write(dev, AC97_RESET, 0x0000);	snooze(50000); // 50 ms		dev->codec_3d_stereo_enhancement = stereo_enhancement_technique[(ac97_reg_cached_read(dev, AC97_RESET) >> 10) & 31];	dev->capabilities = 0;	ac97_reg_update_bits(dev, AC97_EXTENDED_STAT_CTRL, 1, 1); // enable variable rate audio	ac97_detect_capabilities(dev);	dev->init(dev);	dev->amp_enable(dev, true);		/* set defaults, PCM-out and CD-out enabled */	ac97_reg_update(dev, AC97_CENTER_LFE_VOLUME, 0x0000); 	/* set LFE & center volume 0dB */	ac97_reg_update(dev, AC97_SURR_VOLUME, 0x0000); 		/* set surround volume 0dB */	ac97_reg_update(dev, AC97_MASTER_VOLUME, 0x0000); 		/* set master output 0dB */	ac97_reg_update(dev, AC97_AUX_OUT_VOLUME, 0x0000); 		/* set aux output 0dB */	ac97_reg_update(dev, AC97_MONO_VOLUME, 0x0000); 		/* set mono output 0dB */	ac97_reg_update(dev, AC97_CD_VOLUME, 0x0808); 			/* enable cd */	ac97_reg_update(dev, AC97_PCM_OUT_VOLUME, 0x0808); 		/* enable pcm */		ac97_dump_capabilities(dev);}