drivers/net/wireless/wl12xx/wl1271_ps.c

   1 /*
   2  * This file is part of wl1271
   3  *
   4  * Copyright (C) 2008-2009 Nokia Corporation
   5  *
   6  * Contact: Luciano Coelho <luciano.coelho@nokia.com>
   7  *
   8  * This program is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU General Public License
  10  * version 2 as published by the Free Software Foundation.
  11  *
  12  * This program is distributed in the hope that it will be useful, but
  13  * WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with this program; if not, write to the Free Software
  19  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
  20  * 02110-1301 USA
  21  *
  22  */
  23
  24 #include "wl1271_reg.h"
  25 #include "wl1271_ps.h"
  26 #include "wl1271_spi.h"
  27
  28 #define WL1271_WAKEUP_TIMEOUT 500
  29
  30 /* Routines to toggle sleep mode while in ELP */
  31 void wl1271_ps_elp_sleep(struct wl1271 *wl)
  32 {
  33         /*
  34          * FIXME: due to a problem in the firmware (causing a firmware
  35          * crash), ELP entry is prevented below. Remove the "true" to
  36          * re-enable ELP entry.
  37          */
  38         if (true || wl->elp || !wl->psm)
  39                 return;
  40
  41         /*
  42          * Go to ELP unless there is work already pending - pending work
  43          * will immediately wakeup the chipset anyway.
  44          */
  45         if (!work_pending(&wl->irq_work) && !work_pending(&wl->tx_work)) {
  46                 wl1271_debug(DEBUG_PSM, "chip to elp");
  47                 wl1271_write32(wl, HW_ACCESS_ELP_CTRL_REG_ADDR, ELPCTRL_SLEEP);
  48                 wl->elp = true;
  49         }
  50 }
  51
  52 int wl1271_ps_elp_wakeup(struct wl1271 *wl, bool chip_awake)
  53 {
  54         DECLARE_COMPLETION_ONSTACK(compl);
  55         unsigned long flags;
  56         int ret;
  57         u32 start_time = jiffies;
  58         bool pending = false;
  59
  60         if (!wl->elp)
  61                 return 0;
  62
  63         wl1271_debug(DEBUG_PSM, "waking up chip from elp");
  64
  65         /*
  66          * The spinlock is required here to synchronize both the work and
  67          * the completion variable in one entity.
  68          */
  69         spin_lock_irqsave(&wl->wl_lock, flags);
  70         if (work_pending(&wl->irq_work) || chip_awake)
  71                 pending = true;
  72         else
  73                 wl->elp_compl = &compl;
  74         spin_unlock_irqrestore(&wl->wl_lock, flags);
  75
  76         wl1271_write32(wl, HW_ACCESS_ELP_CTRL_REG_ADDR, ELPCTRL_WAKE_UP);
  77
  78         if (!pending) {
  79                 ret = wait_for_completion_timeout(
  80                         &compl, msecs_to_jiffies(WL1271_WAKEUP_TIMEOUT));
  81                 if (ret == 0) {
  82                         wl1271_error("ELP wakeup timeout!");
  83                         ret = -ETIMEDOUT;
  84                         goto err;
  85                 } else if (ret < 0) {
  86                         wl1271_error("ELP wakeup completion error.");
  87                         goto err;
  88                 }
  89         }
  90
  91         wl->elp = false;
  92
  93         wl1271_debug(DEBUG_PSM, "wakeup time: %u ms",
  94                      jiffies_to_msecs(jiffies - start_time));
  95         goto out;
  96
  97 err:
  98         spin_lock_irqsave(&wl->wl_lock, flags);
  99         wl->elp_compl = NULL;
 100         spin_unlock_irqrestore(&wl->wl_lock, flags);
 101         return ret;
 102
 103 out:
 104         return 0;
 105 }
 106
 107 int wl1271_ps_set_mode(struct wl1271 *wl, enum wl1271_cmd_ps_mode mode)
 108 {
 109         int ret;
 110
 111         switch (mode) {
 112         case STATION_POWER_SAVE_MODE:
 113                 wl1271_debug(DEBUG_PSM, "entering psm");
 114                 ret = wl1271_cmd_ps_mode(wl, STATION_POWER_SAVE_MODE);
 115                 if (ret < 0)
 116                         return ret;
 117
 118                 wl1271_ps_elp_sleep(wl);
 119                 if (ret < 0)
 120                         return ret;
 121
 122                 wl->psm = 1;
 123                 break;
 124         case STATION_ACTIVE_MODE:
 125         default:
 126                 wl1271_debug(DEBUG_PSM, "leaving psm");
 127                 ret = wl1271_ps_elp_wakeup(wl, false);
 128                 if (ret < 0)
 129                         return ret;
 130
 131                 ret = wl1271_cmd_ps_mode(wl, STATION_ACTIVE_MODE);
 132                 if (ret < 0)
 133                         return ret;
 134
 135                 wl->psm = 0;
 136                 break;
 137         }
 138
 139         return ret;
 140 }
 141
 142