1 | // SPDX-License-Identifier: GPL-2.0-or-later |
2 | /* |
3 | * Power management for audio on multifunction CS5535 companion device |
4 | * Copyright (C) Jaya Kumar |
5 | */ |
6 | |
7 | #include <linux/init.h> |
8 | #include <linux/pci.h> |
9 | #include <linux/delay.h> |
10 | #include <sound/core.h> |
11 | #include <sound/control.h> |
12 | #include <sound/initval.h> |
13 | #include <sound/asoundef.h> |
14 | #include <sound/pcm.h> |
15 | #include <sound/ac97_codec.h> |
16 | #include "cs5535audio.h" |
17 | |
18 | static void snd_cs5535audio_stop_hardware(struct cs5535audio *cs5535au) |
19 | { |
20 | /* |
21 | we depend on snd_ac97_suspend to tell the |
22 | AC97 codec to shutdown. the amd spec suggests |
23 | that the LNK_SHUTDOWN be done at the same time |
24 | that the codec power-down is issued. instead, |
25 | we do it just after rather than at the same |
26 | time. excluding codec specific build_ops->suspend |
27 | ac97 powerdown hits: |
28 | 0x8000 EAPD |
29 | 0x4000 Headphone amplifier |
30 | 0x0300 ADC & DAC |
31 | 0x0400 Analog Mixer powerdown (Vref on) |
32 | I am not sure if this is the best that we can do. |
33 | The remainder to be investigated are: |
34 | - analog mixer (vref off) 0x0800 |
35 | - AC-link powerdown 0x1000 |
36 | - codec internal clock 0x2000 |
37 | */ |
38 | |
39 | /* set LNK_SHUTDOWN to shutdown AC link */ |
40 | cs_writel(cs5535au, ACC_CODEC_CNTL, ACC_CODEC_CNTL_LNK_SHUTDOWN); |
41 | |
42 | } |
43 | |
44 | static int __maybe_unused snd_cs5535audio_suspend(struct device *dev) |
45 | { |
46 | struct snd_card *card = dev_get_drvdata(dev); |
47 | struct cs5535audio *cs5535au = card->private_data; |
48 | int i; |
49 | |
50 | snd_power_change_state(card, SNDRV_CTL_POWER_D3hot); |
51 | snd_ac97_suspend(ac97: cs5535au->ac97); |
52 | for (i = 0; i < NUM_CS5535AUDIO_DMAS; i++) { |
53 | struct cs5535audio_dma *dma = &cs5535au->dmas[i]; |
54 | if (dma && dma->substream) |
55 | dma->saved_prd = dma->ops->read_prd(cs5535au); |
56 | } |
57 | /* save important regs, then disable aclink in hw */ |
58 | snd_cs5535audio_stop_hardware(cs5535au); |
59 | return 0; |
60 | } |
61 | |
62 | static int __maybe_unused snd_cs5535audio_resume(struct device *dev) |
63 | { |
64 | struct snd_card *card = dev_get_drvdata(dev); |
65 | struct cs5535audio *cs5535au = card->private_data; |
66 | u32 tmp; |
67 | int timeout; |
68 | int i; |
69 | |
70 | /* set LNK_WRM_RST to reset AC link */ |
71 | cs_writel(cs5535au, ACC_CODEC_CNTL, ACC_CODEC_CNTL_LNK_WRM_RST); |
72 | |
73 | timeout = 50; |
74 | do { |
75 | tmp = cs_readl(cs5535au, ACC_CODEC_STATUS); |
76 | if (tmp & PRM_RDY_STS) |
77 | break; |
78 | udelay(1); |
79 | } while (--timeout); |
80 | |
81 | if (!timeout) |
82 | dev_err(cs5535au->card->dev, "Failure getting AC Link ready\n" ); |
83 | |
84 | /* set up rate regs, dma. actual initiation is done in trig */ |
85 | for (i = 0; i < NUM_CS5535AUDIO_DMAS; i++) { |
86 | struct cs5535audio_dma *dma = &cs5535au->dmas[i]; |
87 | if (dma && dma->substream) { |
88 | dma->substream->ops->prepare(dma->substream); |
89 | dma->ops->setup_prd(cs5535au, dma->saved_prd); |
90 | } |
91 | } |
92 | |
93 | /* we depend on ac97 to perform the codec power up */ |
94 | snd_ac97_resume(ac97: cs5535au->ac97); |
95 | snd_power_change_state(card, SNDRV_CTL_POWER_D0); |
96 | |
97 | return 0; |
98 | } |
99 | |
100 | SIMPLE_DEV_PM_OPS(snd_cs5535audio_pm, snd_cs5535audio_suspend, snd_cs5535audio_resume); |
101 | |