LXR linux/sound/usb/power.c

   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(sizeof(*pd), GFP_KERNEL);
  24        if (!pd)
  25                return NULL;
  26
  27        p = NULL;
  28        while ((p = snd_usb_find_csint_desc(ctrl_iface->extra,
  29                                            ctrl_iface->extralen,
  30                                            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(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(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, idx,
  66                              &current_state, 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(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, idx,
  82                              &state, 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