git.openwrt.org Git - openwrt/staging/wigyori.git/blob

   1 --- a/drivers/bus/mhi/host/init.c
   2 +++ b/drivers/bus/mhi/host/init.c
   3 @@ -43,6 +43,7 @@ const char * const dev_state_tran_str[DE
   4         [DEV_ST_TRANSITION_FP] = "FLASH PROGRAMMER",
   5         [DEV_ST_TRANSITION_SYS_ERR] = "SYS ERROR",
   6         [DEV_ST_TRANSITION_DISABLE] = "DISABLE",
   7 +       [DEV_ST_TRANSITION_DISABLE_DESTROY_DEVICE] = "DISABLE (DESTROY DEVICE)",
   8  };
   9
  10  const char * const mhi_ch_state_type_str[MHI_CH_STATE_TYPE_MAX] = {
  11 --- a/drivers/bus/mhi/host/internal.h
  12 +++ b/drivers/bus/mhi/host/internal.h
  13 @@ -69,6 +69,7 @@ enum dev_st_transition {
  14         DEV_ST_TRANSITION_FP,
  15         DEV_ST_TRANSITION_SYS_ERR,
  16         DEV_ST_TRANSITION_DISABLE,
  17 +       DEV_ST_TRANSITION_DISABLE_DESTROY_DEVICE,
  18         DEV_ST_TRANSITION_MAX,
  19  };
  20
  21 --- a/drivers/bus/mhi/host/pm.c
  22 +++ b/drivers/bus/mhi/host/pm.c
  23 @@ -466,7 +466,8 @@ error_mission_mode:
  24  }
  25
  26  /* Handle shutdown transitions */
  27 -static void mhi_pm_disable_transition(struct mhi_controller *mhi_cntrl)
  28 +static void mhi_pm_disable_transition(struct mhi_controller *mhi_cntrl,
  29 +                                     bool destroy_device)
  30  {
  31         enum mhi_pm_state cur_state;
  32         struct mhi_event *mhi_event;
  33 @@ -528,8 +529,16 @@ skip_mhi_reset:
  34         dev_dbg(dev, "Waiting for all pending threads to complete\n");
  35         wake_up_all(&mhi_cntrl->state_event);
  36
  37 -       dev_dbg(dev, "Reset all active channels and remove MHI devices\n");
  38 -       device_for_each_child(&mhi_cntrl->mhi_dev->dev, NULL, mhi_destroy_device);
  39 +       /*
  40 +        * Only destroy the 'struct device' for channels if indicated by the
  41 +        * 'destroy_device' flag. Because, during system suspend or hibernation
  42 +        * state, there is no need to destroy the 'struct device' as the endpoint
  43 +        * device would still be physically attached to the machine.
  44 +        */
  45 +       if (destroy_device) {
  46 +               dev_dbg(dev, "Reset all active channels and remove MHI devices\n");
  47 +               device_for_each_child(&mhi_cntrl->mhi_dev->dev, NULL, mhi_destroy_device);
  48 +       }
  49
  50         mutex_lock(&mhi_cntrl->pm_mutex);
  51
  52 @@ -820,7 +829,10 @@ void mhi_pm_st_worker(struct work_struct
  53                         mhi_pm_sys_error_transition(mhi_cntrl);
  54                         break;
  55                 case DEV_ST_TRANSITION_DISABLE:
  56 -                       mhi_pm_disable_transition(mhi_cntrl);
  57 +                       mhi_pm_disable_transition(mhi_cntrl, false);
  58 +                       break;
  59 +               case DEV_ST_TRANSITION_DISABLE_DESTROY_DEVICE:
  60 +                       mhi_pm_disable_transition(mhi_cntrl, true);
  61                         break;
  62                 default:
  63                         break;
  64 @@ -1174,7 +1186,8 @@ error_exit:
  65  }
  66  EXPORT_SYMBOL_GPL(mhi_async_power_up);
  67
  68 -void mhi_power_down(struct mhi_controller *mhi_cntrl, bool graceful)
  69 +static void __mhi_power_down(struct mhi_controller *mhi_cntrl, bool graceful,
  70 +                            bool destroy_device)
  71  {
  72         enum mhi_pm_state cur_state, transition_state;
  73         struct device *dev = &mhi_cntrl->mhi_dev->dev;
  74 @@ -1210,15 +1223,32 @@ void mhi_power_down(struct mhi_controlle
  75         write_unlock_irq(&mhi_cntrl->pm_lock);
  76         mutex_unlock(&mhi_cntrl->pm_mutex);
  77
  78 -       mhi_queue_state_transition(mhi_cntrl, DEV_ST_TRANSITION_DISABLE);
  79 +       if (destroy_device)
  80 +               mhi_queue_state_transition(mhi_cntrl,
  81 +                                          DEV_ST_TRANSITION_DISABLE_DESTROY_DEVICE);
  82 +       else
  83 +               mhi_queue_state_transition(mhi_cntrl,
  84 +                                          DEV_ST_TRANSITION_DISABLE);
  85
  86         /* Wait for shutdown to complete */
  87         flush_work(&mhi_cntrl->st_worker);
  88
  89         disable_irq(mhi_cntrl->irq[0]);
  90  }
  91 +
  92 +void mhi_power_down(struct mhi_controller *mhi_cntrl, bool graceful)
  93 +{
  94 +       __mhi_power_down(mhi_cntrl, graceful, true);
  95 +}
  96  EXPORT_SYMBOL_GPL(mhi_power_down);
  97
  98 +void mhi_power_down_keep_dev(struct mhi_controller *mhi_cntrl,
  99 +                              bool graceful)
 100 +{
 101 +       __mhi_power_down(mhi_cntrl, graceful, false);
 102 +}
 103 +EXPORT_SYMBOL_GPL(mhi_power_down_keep_dev);
 104 +
 105  int mhi_sync_power_up(struct mhi_controller *mhi_cntrl)
 106  {
 107         int ret = mhi_async_power_up(mhi_cntrl);
 108 --- a/include/linux/mhi.h
 109 +++ b/include/linux/mhi.h
 110 @@ -649,13 +649,29 @@ int mhi_async_power_up(struct mhi_contro
 111  int mhi_sync_power_up(struct mhi_controller *mhi_cntrl);
 112
 113  /**
 114 - * mhi_power_down - Start MHI power down sequence
 115 + * mhi_power_down - Power down the MHI device and also destroy the
 116 + *                  'struct device' for the channels associated with it.
 117 + *                  See also mhi_power_down_keep_dev() which is a variant
 118 + *                  of this API that keeps the 'struct device' for channels
 119 + *                  (useful during suspend/hibernation).
 120   * @mhi_cntrl: MHI controller
 121   * @graceful: Link is still accessible, so do a graceful shutdown process
 122   */
 123  void mhi_power_down(struct mhi_controller *mhi_cntrl, bool graceful);
 124
 125  /**
 126 + * mhi_power_down_keep_dev - Power down the MHI device but keep the 'struct
 127 + *                           device' for the channels associated with it.
 128 + *                           This is a variant of 'mhi_power_down()' and
 129 + *                           useful in scenarios such as suspend/hibernation
 130 + *                           where destroying of the 'struct device' is not
 131 + *                           needed.
 132 + * @mhi_cntrl: MHI controller
 133 + * @graceful: Link is still accessible, so do a graceful shutdown process
 134 + */
 135 +void mhi_power_down_keep_dev(struct mhi_controller *mhi_cntrl, bool graceful);
 136 +
 137 +/**
 138   * mhi_unprepare_after_power_down - Free any allocated memory after power down
 139   * @mhi_cntrl: MHI controller
 140   */