// SPDX-License-Identifier: GPL-2.0-or-later /* * Power management for audio on multifunction CS5535 companion device * Copyright (C) Jaya Kumar */ #include <linux/init.h> #include <linux/pci.h> #include <linux/delay.h> #include <sound/core.h> #include <sound/control.h> #include <sound/initval.h> #include <sound/asoundef.h> #include <sound/pcm.h> #include <sound/ac97_codec.h> #include "cs5535audio.h" static void snd_cs5535audio_stop_hardware(struct cs5535audio *cs5535au) { /* we depend on snd_ac97_suspend to tell the AC97 codec to shutdown. the amd spec suggests that the LNK_SHUTDOWN be done at the same time that the codec power-down is issued. instead, we do it just after rather than at the same time. excluding codec specific build_ops->suspend ac97 powerdown hits: 0x8000 EAPD 0x4000 Headphone amplifier 0x0300 ADC & DAC 0x0400 Analog Mixer powerdown (Vref on) I am not sure if this is the best that we can do. The remainder to be investigated are: - analog mixer (vref off) 0x0800 - AC-link powerdown 0x1000 - codec internal clock 0x2000 */ /* set LNK_SHUTDOWN to shutdown AC link */ cs_writel(cs5535au, ACC_CODEC_CNTL, ACC_CODEC_CNTL_LNK_SHUTDOWN); } static int __maybe_unused snd_cs5535audio_suspend(struct device *dev) { struct snd_card *card = dev_get_drvdata(dev); struct cs5535audio *cs5535au = card->private_data; int i; snd_power_change_state(card, SNDRV_CTL_POWER_D3hot); snd_ac97_suspend(cs5535au->ac97); for (i = 0; i < NUM_CS5535AUDIO_DMAS; i++) { struct cs5535audio_dma *dma = &cs5535au->dmas[i]; if (dma && dma->substream) dma->saved_prd = dma->ops->read_prd(cs5535au); } /* save important regs, then disable aclink in hw */ snd_cs5535audio_stop_hardware(cs5535au); return 0; } static int __maybe_unused snd_cs5535audio_resume(struct device *dev) { struct snd_card *card = dev_get_drvdata(dev); struct cs5535audio *cs5535au = card->private_data; u32 tmp; int timeout; int i; /* set LNK_WRM_RST to reset AC link */ cs_writel(cs5535au, ACC_CODEC_CNTL, ACC_CODEC_CNTL_LNK_WRM_RST); timeout = 50; do { tmp = cs_readl(cs5535au, ACC_CODEC_STATUS); if (tmp & PRM_RDY_STS) break; udelay(1); } while (--timeout); if (!timeout) dev_err(cs5535au->card->dev, "Failure getting AC Link ready\n"); /* set up rate regs, dma. actual initiation is done in trig */ for (i = 0; i < NUM_CS5535AUDIO_DMAS; i++) { struct cs5535audio_dma *dma = &cs5535au->dmas[i]; if (dma && dma->substream) { dma->substream->ops->prepare(dma->substream); dma->ops->setup_prd(cs5535au, dma->saved_prd); } } /* we depend on ac97 to perform the codec power up */ snd_ac97_resume(cs5535au->ac97); snd_power_change_state(card, SNDRV_CTL_POWER_D0); return 0; } SIMPLE_DEV_PM_OPS(snd_cs5535audio_pm, snd_cs5535audio_suspend, snd_cs5535audio_resume); |