drivers/net/wireless/wl1251/ps.c

   1 /*
   2  * This file is part of wl1251
   3  *
   4  * Copyright (C) 2008 Nokia Corporation
   5  *
   6  * This program is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU General Public License
   8  * version 2 as published by the Free Software Foundation.
   9  *
  10  * This program is distributed in the hope that it will be useful, but
  11  * WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13  * General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with this program; if not, write to the Free Software
  17  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
  18  * 02110-1301 USA
  19  *
  20  */
  21
  22 #include "reg.h"
  23 #include "ps.h"
  24 #include "cmd.h"
  25 #include "io.h"
  26
  27 /* in ms */
  28 #define WL1251_WAKEUP_TIMEOUT 100
  29
  30 void wl1251_elp_work(struct work_struct *work)
  31 {
  32         struct delayed_work *dwork;
  33         struct wl1251 *wl;
  34
  35         dwork = container_of(work, struct delayed_work, work);
  36         wl = container_of(dwork, struct wl1251, elp_work);
  37
  38         wl1251_debug(DEBUG_PSM, "elp work");
  39
  40         mutex_lock(&wl->mutex);
  41
  42         if (wl->elp || !wl->psm)
  43                 goto out;
  44
  45         wl1251_debug(DEBUG_PSM, "chip to elp");
  46         wl1251_write_elp(wl, HW_ACCESS_ELP_CTRL_REG_ADDR, ELPCTRL_SLEEP);
  47         wl->elp = true;
  48
  49 out:
  50         mutex_unlock(&wl->mutex);
  51 }
  52
  53 #define ELP_ENTRY_DELAY  5
  54
  55 /* Routines to toggle sleep mode while in ELP */
  56 void wl1251_ps_elp_sleep(struct wl1251 *wl)
  57 {
  58         unsigned long delay;
  59
  60         if (wl->psm) {
  61                 cancel_delayed_work(&wl->elp_work);
  62                 delay = msecs_to_jiffies(ELP_ENTRY_DELAY);
  63                 ieee80211_queue_delayed_work(wl->hw, &wl->elp_work, delay);
  64         }
  65 }
  66
  67 int wl1251_ps_elp_wakeup(struct wl1251 *wl)
  68 {
  69         unsigned long timeout, start;
  70         u32 elp_reg;
  71
  72         if (!wl->elp)
  73                 return 0;
  74
  75         wl1251_debug(DEBUG_PSM, "waking up chip from elp");
  76
  77         start = jiffies;
  78         timeout = jiffies + msecs_to_jiffies(WL1251_WAKEUP_TIMEOUT);
  79
  80         wl1251_write_elp(wl, HW_ACCESS_ELP_CTRL_REG_ADDR, ELPCTRL_WAKE_UP);
  81
  82         elp_reg = wl1251_read_elp(wl, HW_ACCESS_ELP_CTRL_REG_ADDR);
  83
  84         /*
  85          * FIXME: we should wait for irq from chip but, as a temporary
  86          * solution to simplify locking, let's poll instead
  87          */
  88         while (!(elp_reg & ELPCTRL_WLAN_READY)) {
  89                 if (time_after(jiffies, timeout)) {
  90                         wl1251_error("elp wakeup timeout");
  91                         return -ETIMEDOUT;
  92                 }
  93                 msleep(1);
  94                 elp_reg = wl1251_read_elp(wl, HW_ACCESS_ELP_CTRL_REG_ADDR);
  95         }
  96
  97         wl1251_debug(DEBUG_PSM, "wakeup time: %u ms",
  98                      jiffies_to_msecs(jiffies - start));
  99
 100         wl->elp = false;
 101
 102         return 0;
 103 }
 104
 105 static int wl1251_ps_set_elp(struct wl1251 *wl, bool enable)
 106 {
 107         int ret;
 108
 109         if (enable) {
 110                 wl1251_debug(DEBUG_PSM, "sleep auth psm/elp");
 111
 112                 ret = wl1251_acx_sleep_auth(wl, WL1251_PSM_ELP);
 113                 if (ret < 0)
 114                         return ret;
 115
 116                 wl1251_ps_elp_sleep(wl);
 117         } else {
 118                 wl1251_debug(DEBUG_PSM, "sleep auth cam");
 119
 120                 /*
 121                  * When the target is in ELP, we can only
 122                  * access the ELP control register. Thus,
 123                  * we have to wake the target up before
 124                  * changing the power authorization.
 125                  */
 126
 127                 wl1251_ps_elp_wakeup(wl);
 128
 129                 ret = wl1251_acx_sleep_auth(wl, WL1251_PSM_CAM);
 130                 if (ret < 0)
 131                         return ret;
 132         }
 133
 134         return 0;
 135 }
 136
 137 int wl1251_ps_set_mode(struct wl1251 *wl, enum wl1251_cmd_ps_mode mode)
 138 {
 139         int ret;
 140
 141         switch (mode) {
 142         case STATION_POWER_SAVE_MODE:
 143                 wl1251_debug(DEBUG_PSM, "entering psm");
 144
 145                 /* enable beacon filtering */
 146                 ret = wl1251_acx_beacon_filter_opt(wl, true);
 147                 if (ret < 0)
 148                         return ret;
 149
 150                 ret = wl1251_acx_wake_up_conditions(wl,
 151                                                     WAKE_UP_EVENT_DTIM_BITMAP,
 152                                                     wl->listen_int);
 153                 if (ret < 0)
 154                         return ret;
 155
 156                 ret = wl1251_cmd_ps_mode(wl, STATION_POWER_SAVE_MODE);
 157                 if (ret < 0)
 158                         return ret;
 159
 160                 ret = wl1251_ps_set_elp(wl, true);
 161                 if (ret < 0)
 162                         return ret;
 163
 164                 wl->psm = 1;
 165                 break;
 166         case STATION_ACTIVE_MODE:
 167         default:
 168                 wl1251_debug(DEBUG_PSM, "leaving psm");
 169                 ret = wl1251_ps_set_elp(wl, false);
 170                 if (ret < 0)
 171                         return ret;
 172
 173                 /* disable beacon filtering */
 174                 ret = wl1251_acx_beacon_filter_opt(wl, false);
 175                 if (ret < 0)
 176                         return ret;
 177
 178                 ret = wl1251_acx_wake_up_conditions(wl,
 179                                                     WAKE_UP_EVENT_DTIM_BITMAP,
 180                                                     wl->listen_int);
 181                 if (ret < 0)
 182                         return ret;
 183
 184                 ret = wl1251_cmd_ps_mode(wl, STATION_ACTIVE_MODE);
 185                 if (ret < 0)
 186                         return ret;
 187
 188                 wl->psm = 0;
 189                 break;
 190         }
 191
 192         return ret;
 193 }
 194