drivers/net/wireless/wl12xx/wl1251_ps.c

   1 /*
   2  * This file is part of wl1251
   3  *
   4  * Copyright (C) 2008 Nokia Corporation
   5  *
   6  * Contact: Kalle Valo <kalle.valo@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 "reg.h"
  25 #include "wl1251_ps.h"
  26 #include "wl1251_cmd.h"
  27 #include "wl1251_io.h"
  28
  29 #define WL1251_WAKEUP_TIMEOUT 2000
  30
  31 /* Routines to toggle sleep mode while in ELP */
  32 void wl1251_ps_elp_sleep(struct wl1251 *wl)
  33 {
  34         if (wl->elp || !wl->psm)
  35                 return;
  36
  37         wl1251_debug(DEBUG_PSM, "chip to elp");
  38
  39         wl1251_write32(wl, HW_ACCESS_ELP_CTRL_REG_ADDR, ELPCTRL_SLEEP);
  40
  41         wl->elp = true;
  42 }
  43
  44 int wl1251_ps_elp_wakeup(struct wl1251 *wl)
  45 {
  46         unsigned long timeout;
  47         u32 elp_reg;
  48
  49         if (!wl->elp)
  50                 return 0;
  51
  52         wl1251_debug(DEBUG_PSM, "waking up chip from elp");
  53
  54         timeout = jiffies + msecs_to_jiffies(WL1251_WAKEUP_TIMEOUT);
  55
  56         wl1251_write32(wl, HW_ACCESS_ELP_CTRL_REG_ADDR, ELPCTRL_WAKE_UP);
  57
  58         elp_reg = wl1251_read32(wl, HW_ACCESS_ELP_CTRL_REG_ADDR);
  59
  60         /*
  61          * FIXME: we should wait for irq from chip but, as a temporary
  62          * solution to simplify locking, let's poll instead
  63          */
  64         while (!(elp_reg & ELPCTRL_WLAN_READY)) {
  65                 if (time_after(jiffies, timeout)) {
  66                         wl1251_error("elp wakeup timeout");
  67                         return -ETIMEDOUT;
  68                 }
  69                 msleep(1);
  70                 elp_reg = wl1251_read32(wl, HW_ACCESS_ELP_CTRL_REG_ADDR);
  71         }
  72
  73         wl1251_debug(DEBUG_PSM, "wakeup time: %u ms",
  74                      jiffies_to_msecs(jiffies) -
  75                      (jiffies_to_msecs(timeout) - WL1251_WAKEUP_TIMEOUT));
  76
  77         wl->elp = false;
  78
  79         return 0;
  80 }
  81
  82 static int wl1251_ps_set_elp(struct wl1251 *wl, bool enable)
  83 {
  84         int ret;
  85
  86         if (enable) {
  87                 wl1251_debug(DEBUG_PSM, "sleep auth psm/elp");
  88
  89                 ret = wl1251_acx_sleep_auth(wl, WL1251_PSM_ELP);
  90                 if (ret < 0)
  91                         return ret;
  92
  93                 wl1251_ps_elp_sleep(wl);
  94         } else {
  95                 wl1251_debug(DEBUG_PSM, "sleep auth cam");
  96
  97                 /*
  98                  * When the target is in ELP, we can only
  99                  * access the ELP control register. Thus,
 100                  * we have to wake the target up before
 101                  * changing the power authorization.
 102                  */
 103
 104                 wl1251_ps_elp_wakeup(wl);
 105
 106                 ret = wl1251_acx_sleep_auth(wl, WL1251_PSM_CAM);
 107                 if (ret < 0)
 108                         return ret;
 109         }
 110
 111         return 0;
 112 }
 113
 114 int wl1251_ps_set_mode(struct wl1251 *wl, enum wl1251_cmd_ps_mode mode)
 115 {
 116         int ret;
 117
 118         switch (mode) {
 119         case STATION_POWER_SAVE_MODE:
 120                 wl1251_debug(DEBUG_PSM, "entering psm");
 121                 ret = wl1251_cmd_ps_mode(wl, STATION_POWER_SAVE_MODE);
 122                 if (ret < 0)
 123                         return ret;
 124
 125                 ret = wl1251_ps_set_elp(wl, true);
 126                 if (ret < 0)
 127                         return ret;
 128
 129                 wl->psm = 1;
 130                 break;
 131         case STATION_ACTIVE_MODE:
 132         default:
 133                 wl1251_debug(DEBUG_PSM, "leaving psm");
 134                 ret = wl1251_ps_set_elp(wl, false);
 135                 if (ret < 0)
 136                         return ret;
 137
 138                 ret = wl1251_cmd_ps_mode(wl, STATION_ACTIVE_MODE);
 139                 if (ret < 0)
 140                         return ret;
 141
 142                 wl->psm = 0;
 143                 break;
 144         }
 145
 146         return ret;
 147 }
 148