Quelle  pm.c   Sprache: C

// SPDX-License-Identifier: ISC
/*
 * Copyright (c) 2014,2017 Qualcomm Atheros, Inc.
 * Copyright (c) 2018-2019, The Linux Foundation. All rights reserved.
 */

#include "wil6210.h"
#include <linux/jiffies.h>
#include <linux/pm_runtime.h>

#define WIL6210_AUTOSUSPEND_DELAY_MS (1000)

static void wil_pm_wake_connected_net_queues(struct wil6210_priv *wil)
{
 int i;

 mutex_lock(&wil->vif_mutex);
 for (i = 0; i < GET_MAX_VIFS(wil); i++) {
  struct wil6210_vif *vif = wil->vifs[i];

  if (vif && test_bit(wil_vif_fwconnected, vif->status))
   wil_update_net_queues_bh(wil, vif, NULL, false);
 }
 mutex_unlock(&wil->vif_mutex);
}

static void wil_pm_stop_all_net_queues(struct wil6210_priv *wil)
{
 int i;

 mutex_lock(&wil->vif_mutex);
 for (i = 0; i < GET_MAX_VIFS(wil); i++) {
  struct wil6210_vif *vif = wil->vifs[i];

  if (vif)
   wil_update_net_queues_bh(wil, vif, NULL, true);
 }
 mutex_unlock(&wil->vif_mutex);
}

static bool
wil_can_suspend_vif(struct wil6210_priv *wil, struct wil6210_vif *vif,
      bool is_runtime)
{
 struct wireless_dev *wdev = vif_to_wdev(vif);

 switch (wdev->iftype) {
 case NL80211_IFTYPE_MONITOR:
  wil_dbg_pm(wil, "Sniffer\n");
  return false;

 /* for STA-like interface, don't runtime suspend */
 case NL80211_IFTYPE_STATION:
 case NL80211_IFTYPE_P2P_CLIENT:
  if (test_bit(wil_vif_fwconnecting, vif->status)) {
   wil_dbg_pm(wil, "Delay suspend when connecting\n");
   return false;
  }
  if (is_runtime) {
   wil_dbg_pm(wil, "STA-like interface\n");
   return false;
  }
  break;
 /* AP-like interface - can't suspend */
 default:
  wil_dbg_pm(wil, "AP-like interface\n");
  return false;
 }

 return true;
}

int wil_can_suspend(struct wil6210_priv *wil, bool is_runtime)
{
 int rc = 0, i;
 bool wmi_only = test_bit(WMI_FW_CAPABILITY_WMI_ONLY,
     wil->fw_capabilities);
 bool active_ifaces;

 wil_dbg_pm(wil, "can_suspend: %s\n", is_runtime ? "runtime" : "system");

 if (wmi_only || debug_fw) {
  wil_dbg_pm(wil, "Deny any suspend - %s mode\n",
      wmi_only ? "wmi_only" : "debug_fw");
  rc = -EBUSY;
  goto out;
 }
 if (is_runtime && !wil->platform_ops.suspend) {
  rc = -EBUSY;
  goto out;
 }

 mutex_lock(&wil->vif_mutex);
 active_ifaces = wil_has_active_ifaces(wil, true, false);
 mutex_unlock(&wil->vif_mutex);

 if (!active_ifaces) {
  /* can always sleep when down */
  wil_dbg_pm(wil, "Interface is down\n");
  goto out;
 }
 if (test_bit(wil_status_resetting, wil->status)) {
  wil_dbg_pm(wil, "Delay suspend when resetting\n");
  rc = -EBUSY;
  goto out;
 }
 if (wil->recovery_state != fw_recovery_idle) {
  wil_dbg_pm(wil, "Delay suspend during recovery\n");
  rc = -EBUSY;
  goto out;
 }

 /* interface is running */
 mutex_lock(&wil->vif_mutex);
 for (i = 0; i < GET_MAX_VIFS(wil); i++) {
  struct wil6210_vif *vif = wil->vifs[i];

  if (!vif)
   continue;
  if (!wil_can_suspend_vif(wil, vif, is_runtime)) {
   rc = -EBUSY;
   mutex_unlock(&wil->vif_mutex);
   goto out;
  }
 }
 mutex_unlock(&wil->vif_mutex);

out:
 wil_dbg_pm(wil, "can_suspend: %s => %s (%d)\n",
     is_runtime ? "runtime" : "system", rc ? "No" : "Yes", rc);

 if (rc)
  wil->suspend_stats.rejected_by_host++;

 return rc;
}

static int wil_resume_keep_radio_on(struct wil6210_priv *wil)
{
 int rc = 0;

 /* wil_status_resuming will be cleared when getting
 * WMI_TRAFFIC_RESUME_EVENTID
 */
 set_bit(wil_status_resuming, wil->status);
 clear_bit(wil_status_suspended, wil->status);
 wil_c(wil, RGF_USER_CLKS_CTL_0, BIT_USER_CLKS_RST_PWGD);
 wil_unmask_irq(wil);

 wil6210_bus_request(wil, wil->bus_request_kbps_pre_suspend);

 /* Send WMI resume request to the device */
 rc = wmi_resume(wil);
 if (rc) {
  wil_err(wil, "device failed to resume (%d)\n", rc);
  if (no_fw_recovery)
   goto out;
  rc = wil_down(wil);
  if (rc) {
   wil_err(wil, "wil_down failed (%d)\n", rc);
   goto out;
  }
  rc = wil_up(wil);
  if (rc) {
   wil_err(wil, "wil_up failed (%d)\n", rc);
   goto out;
  }
 }

 /* Wake all queues */
 wil_pm_wake_connected_net_queues(wil);

out:
 if (rc)
  set_bit(wil_status_suspended, wil->status);
 return rc;
}

static int wil_suspend_keep_radio_on(struct wil6210_priv *wil)
{
 int rc = 0;
 unsigned long data_comp_to;

 wil_dbg_pm(wil, "suspend keep radio on\n");

 /* Prevent handling of new tx and wmi commands */
 rc = down_write_trylock(&wil->mem_lock);
 if (!rc) {
  wil_err(wil,
   "device is busy. down_write_trylock failed, returned (0x%x)\n",
   rc);
  wil->suspend_stats.rejected_by_host++;
  return -EBUSY;
 }

 set_bit(wil_status_suspending, wil->status);
 up_write(&wil->mem_lock);

 wil_pm_stop_all_net_queues(wil);

 if (!wil_is_tx_idle(wil)) {
  wil_dbg_pm(wil, "Pending TX data, reject suspend\n");
  wil->suspend_stats.rejected_by_host++;
  goto reject_suspend;
 }

 if (!wil->txrx_ops.is_rx_idle(wil)) {
  wil_dbg_pm(wil, "Pending RX data, reject suspend\n");
  wil->suspend_stats.rejected_by_host++;
  goto reject_suspend;
 }

 if (!wil_is_wmi_idle(wil)) {
  wil_dbg_pm(wil, "Pending WMI events, reject suspend\n");
  wil->suspend_stats.rejected_by_host++;
  goto reject_suspend;
 }

 /* Send WMI suspend request to the device */
 rc = wmi_suspend(wil);
 if (rc) {
  wil_dbg_pm(wil, "wmi_suspend failed, reject suspend (%d)\n",
      rc);
  goto reject_suspend;
 }

 /* Wait for completion of the pending RX packets */
 data_comp_to = jiffies + msecs_to_jiffies(WIL_DATA_COMPLETION_TO_MS);
 if (test_bit(wil_status_napi_en, wil->status)) {
  while (!wil->txrx_ops.is_rx_idle(wil)) {
   if (time_after(jiffies, data_comp_to)) {
    if (wil->txrx_ops.is_rx_idle(wil))
     break;
    wil_err(wil,
     "TO waiting for idle RX, suspend failed\n");
    wil->suspend_stats.r_on.failed_suspends++;
    goto resume_after_fail;
   }
   wil_dbg_ratelimited(wil, "rx vring is not empty -> NAPI\n");
   napi_synchronize(&wil->napi_rx);
   msleep(20);
  }
 }

 /* In case of pending WMI events, reject the suspend
 * and resume the device.
 * This can happen if the device sent the WMI events before
 * approving the suspend.
 */
 if (!wil_is_wmi_idle(wil)) {
  wil_err(wil, "suspend failed due to pending WMI events\n");
  wil->suspend_stats.r_on.failed_suspends++;
  goto resume_after_fail;
 }

 wil_mask_irq(wil);

 /* Disable device reset on PERST */
 wil_s(wil, RGF_USER_CLKS_CTL_0, BIT_USER_CLKS_RST_PWGD);

 if (wil->platform_ops.suspend) {
  rc = wil->platform_ops.suspend(wil->platform_handle, true);
  if (rc) {
   wil_err(wil, "platform device failed to suspend (%d)\n",
    rc);
   wil->suspend_stats.r_on.failed_suspends++;
   wil_c(wil, RGF_USER_CLKS_CTL_0, BIT_USER_CLKS_RST_PWGD);
   wil_unmask_irq(wil);
   goto resume_after_fail;
  }
 }

 /* Save the current bus request to return to the same in resume */
 wil->bus_request_kbps_pre_suspend = wil->bus_request_kbps;
 wil6210_bus_request(wil, 0);

 set_bit(wil_status_suspended, wil->status);
 clear_bit(wil_status_suspending, wil->status);

 return rc;

resume_after_fail:
 set_bit(wil_status_resuming, wil->status);
 clear_bit(wil_status_suspending, wil->status);
 rc = wmi_resume(wil);
 /* if resume succeeded, reject the suspend */
 if (!rc) {
  rc = -EBUSY;
  wil_pm_wake_connected_net_queues(wil);
 }
 return rc;

reject_suspend:
 clear_bit(wil_status_suspending, wil->status);
 wil_pm_wake_connected_net_queues(wil);
 return -EBUSY;
}

static int wil_suspend_radio_off(struct wil6210_priv *wil)
{
 int rc = 0;
 bool active_ifaces;

 wil_dbg_pm(wil, "suspend radio off\n");

 rc = down_write_trylock(&wil->mem_lock);
 if (!rc) {
  wil_err(wil,
   "device is busy. down_write_trylock failed, returned (0x%x)\n",
   rc);
  wil->suspend_stats.rejected_by_host++;
  return -EBUSY;
 }

 set_bit(wil_status_suspending, wil->status);
 up_write(&wil->mem_lock);

 /* if netif up, hardware is alive, shut it down */
 mutex_lock(&wil->vif_mutex);
 active_ifaces = wil_has_active_ifaces(wil, true, false);
 mutex_unlock(&wil->vif_mutex);

 if (active_ifaces) {
  rc = wil_down(wil);
  if (rc) {
   wil_err(wil, "wil_down : %d\n", rc);
   wil->suspend_stats.r_off.failed_suspends++;
   goto out;
  }
 }

 /* Disable PCIe IRQ to prevent sporadic IRQs when PCIe is suspending */
 wil_dbg_pm(wil, "Disabling PCIe IRQ before suspending\n");
 wil_disable_irq(wil);

 if (wil->platform_ops.suspend) {
  rc = wil->platform_ops.suspend(wil->platform_handle, false);
  if (rc) {
   wil_enable_irq(wil);
   wil->suspend_stats.r_off.failed_suspends++;
   goto out;
  }
 }

 set_bit(wil_status_suspended, wil->status);

out:
 clear_bit(wil_status_suspending, wil->status);
 wil_dbg_pm(wil, "suspend radio off: %d\n", rc);

 return rc;
}

static int wil_resume_radio_off(struct wil6210_priv *wil)
{
 int rc = 0;
 bool active_ifaces;

 wil_dbg_pm(wil, "Enabling PCIe IRQ\n");
 wil_enable_irq(wil);
 /* if any netif up, bring hardware up
 * During open(), IFF_UP set after actual device method
 * invocation. This prevent recursive call to wil_up()
 * wil_status_suspended will be cleared in wil_reset
 */
 mutex_lock(&wil->vif_mutex);
 active_ifaces = wil_has_active_ifaces(wil, true, false);
 mutex_unlock(&wil->vif_mutex);
 if (active_ifaces)
  rc = wil_up(wil);
 else
  clear_bit(wil_status_suspended, wil->status);

 return rc;
}

int wil_suspend(struct wil6210_priv *wil, bool is_runtime, bool keep_radio_on)
{
 int rc = 0;

 wil_dbg_pm(wil, "suspend: %s\n", is_runtime ? "runtime" : "system");

 if (test_bit(wil_status_suspended, wil->status)) {
  wil_dbg_pm(wil, "trying to suspend while suspended\n");
  return 0;
 }

 if (!keep_radio_on)
  rc = wil_suspend_radio_off(wil);
 else
  rc = wil_suspend_keep_radio_on(wil);

 wil_dbg_pm(wil, "suspend: %s => %d\n",
     is_runtime ? "runtime" : "system", rc);

 return rc;
}

int wil_resume(struct wil6210_priv *wil, bool is_runtime, bool keep_radio_on)
{
 int rc = 0;

 wil_dbg_pm(wil, "resume: %s\n", is_runtime ? "runtime" : "system");

 if (wil->platform_ops.resume) {
  rc = wil->platform_ops.resume(wil->platform_handle,
           keep_radio_on);
  if (rc) {
   wil_err(wil, "platform_ops.resume : %d\n", rc);
   goto out;
  }
 }

 if (keep_radio_on)
  rc = wil_resume_keep_radio_on(wil);
 else
  rc = wil_resume_radio_off(wil);

out:
 wil_dbg_pm(wil, "resume: %s => %d\n", is_runtime ? "runtime" : "system",
     rc);
 return rc;
}

void wil_pm_runtime_allow(struct wil6210_priv *wil)
{
 struct device *dev = wil_to_dev(wil);

 pm_runtime_put_noidle(dev);
 pm_runtime_set_autosuspend_delay(dev, WIL6210_AUTOSUSPEND_DELAY_MS);
 pm_runtime_use_autosuspend(dev);
 pm_runtime_allow(dev);
}

void wil_pm_runtime_forbid(struct wil6210_priv *wil)
{
 struct device *dev = wil_to_dev(wil);

 pm_runtime_forbid(dev);
 pm_runtime_get_noresume(dev);
}

int wil_pm_runtime_get(struct wil6210_priv *wil)
{
 int rc;
 struct device *dev = wil_to_dev(wil);

 rc = pm_runtime_resume_and_get(dev);
 if (rc < 0) {
  wil_err(wil, "pm_runtime_resume_and_get() failed, rc = %d\n", rc);
  return rc;
 }

 return 0;
}

void wil_pm_runtime_put(struct wil6210_priv *wil)
{
 struct device *dev = wil_to_dev(wil);

 pm_runtime_mark_last_busy(dev);
 pm_runtime_put_autosuspend(dev);
}