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                for (i = 0; i < pd_desc->bNrEntities; i++) {
  35                        if (pd_desc->baEntityID[i] == id) {
  36                                pd->pd_id = pd_desc->bPowerDomainID;
  37                                pd->pd_d1d0_rec =
  38                                        le16_to_cpu(pd_desc->waRecoveryTime1);
  39                                pd->pd_d2d0_rec =
  40                                        le16_to_cpu(pd_desc->waRecoveryTime2);
  41                                return pd;
  42                        }
  43                }
  44        }
  45
  46        kfree(pd);
  47        return NULL;
  48}
  49
  50int snd_usb_power_domain_set(struct snd_usb_audio *chip,
  51                             struct snd_usb_power_domain *pd,
  52                             unsigned char state)
  53{
  54        struct usb_device *dev = chip->dev;
  55        unsigned char current_state;
  56        int err, idx;
  57
  58        idx = snd_usb_ctrl_intf(chip) | (pd->pd_id << 8);
  59
  60        err = snd_usb_ctl_msg(chip->dev, usb_rcvctrlpipe(chip->dev, 0),
  61                              UAC2_CS_CUR,
  62                              USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_IN,
  63                              UAC3_AC_POWER_DOMAIN_CONTROL << 8, idx,
  64                              &current_state, sizeof(current_state));
  65        if (err < 0) {
  66                dev_err(&dev->dev, "Can't get UAC3 power state for id %d\n",
  67                        pd->pd_id);
  68                return err;
  69        }
  70
  71        if (current_state == state) {
  72                dev_dbg(&dev->dev, "UAC3 power domain id %d already in state %d\n",
  73                        pd->pd_id, state);
  74                return 0;
  75        }
  76
  77        err = snd_usb_ctl_msg(chip->dev, usb_sndctrlpipe(chip->dev, 0), UAC2_CS_CUR,
  78                              USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_OUT,
  79                              UAC3_AC_POWER_DOMAIN_CONTROL << 8, idx,
  80                              &state, sizeof(state));
  81        if (err < 0) {
  82                dev_err(&dev->dev, "Can't set UAC3 power state to %d for id %d\n",
  83                        state, pd->pd_id);
  84                return err;
  85        }
  86
  87        if (state == UAC3_PD_STATE_D0) {
  88                switch (current_state) {
  89                case UAC3_PD_STATE_D2:
  90                        udelay(pd->pd_d2d0_rec * 50);
  91                        break;
  92                case UAC3_PD_STATE_D1:
  93                        udelay(pd->pd_d1d0_rec * 50);
  94                        break;
  95                default:
  96                        return -EINVAL;
  97                }
  98        }
  99
 100        dev_dbg(&dev->dev, "UAC3 power domain id %d change to state %d\n",
 101                pd->pd_id, state);
 102
 103        return 0;
 104}
 105