1// SPDX-License-Identifier: GPL-2.0
2/*
3 * UAC3 Power Domain state management functions
4 */
5
6#include <linux/slab.h>
7#include <linux/usb.h>
8#include <linux/usb/audio.h>
9#include <linux/usb/audio-v2.h>
10#include <linux/usb/audio-v3.h>
11
12#include "usbaudio.h"
13#include "helper.h"
14#include "power.h"
15
16struct snd_usb_power_domain *
17snd_usb_find_power_domain(struct usb_host_interface *ctrl_iface,
18 unsigned char id)
19{
20 struct snd_usb_power_domain *pd;
21 void *p;
22
23 pd = kzalloc(size: sizeof(*pd), GFP_KERNEL);
24 if (!pd)
25 return NULL;
26
27 p = NULL;
28 while ((p = snd_usb_find_csint_desc(descstart: ctrl_iface->extra,
29 desclen: ctrl_iface->extralen,
30 after: p, UAC3_POWER_DOMAIN)) != NULL) {
31 struct uac3_power_domain_descriptor *pd_desc = p;
32 int i;
33
34 if (!snd_usb_validate_audio_desc(p, UAC_VERSION_3))
35 continue;
36 for (i = 0; i < pd_desc->bNrEntities; i++) {
37 if (pd_desc->baEntityID[i] == id) {
38 pd->pd_id = pd_desc->bPowerDomainID;
39 pd->pd_d1d0_rec =
40 le16_to_cpu(pd_desc->waRecoveryTime1);
41 pd->pd_d2d0_rec =
42 le16_to_cpu(pd_desc->waRecoveryTime2);
43 return pd;
44 }
45 }
46 }
47
48 kfree(objp: pd);
49 return NULL;
50}
51
52int snd_usb_power_domain_set(struct snd_usb_audio *chip,
53 struct snd_usb_power_domain *pd,
54 unsigned char state)
55{
56 struct usb_device *dev = chip->dev;
57 unsigned char current_state;
58 int err, idx;
59
60 idx = snd_usb_ctrl_intf(chip) | (pd->pd_id << 8);
61
62 err = snd_usb_ctl_msg(dev: chip->dev, usb_rcvctrlpipe(chip->dev, 0),
63 UAC2_CS_CUR,
64 USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_IN,
65 UAC3_AC_POWER_DOMAIN_CONTROL << 8, index: idx,
66 data: &current_state, size: sizeof(current_state));
67 if (err < 0) {
68 dev_err(&dev->dev, "Can't get UAC3 power state for id %d\n",
69 pd->pd_id);
70 return err;
71 }
72
73 if (current_state == state) {
74 dev_dbg(&dev->dev, "UAC3 power domain id %d already in state %d\n",
75 pd->pd_id, state);
76 return 0;
77 }
78
79 err = snd_usb_ctl_msg(dev: chip->dev, usb_sndctrlpipe(chip->dev, 0), UAC2_CS_CUR,
80 USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_OUT,
81 UAC3_AC_POWER_DOMAIN_CONTROL << 8, index: idx,
82 data: &state, size: sizeof(state));
83 if (err < 0) {
84 dev_err(&dev->dev, "Can't set UAC3 power state to %d for id %d\n",
85 state, pd->pd_id);
86 return err;
87 }
88
89 if (state == UAC3_PD_STATE_D0) {
90 switch (current_state) {
91 case UAC3_PD_STATE_D2:
92 udelay(pd->pd_d2d0_rec * 50);
93 break;
94 case UAC3_PD_STATE_D1:
95 udelay(pd->pd_d1d0_rec * 50);
96 break;
97 default:
98 return -EINVAL;
99 }
100 }
101
102 dev_dbg(&dev->dev, "UAC3 power domain id %d change to state %d\n",
103 pd->pd_id, state);
104
105 return 0;
106}
107

source code of linux/sound/usb/power.c