/*************************************************************************** * __________ __ ___. * Open \______ \ ____ ____ | | _\_ |__ _______ ___ * Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ / * Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < < * Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \ * \/ \/ \/ \/ \/ * $Id$ * * Copyright (C) 2002 by Heikki Hannikainen * * All files in this archive are subject to the GNU General Public License. * See the file COPYING in the source tree root for full license agreement. * * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY * KIND, either express or implied. * ****************************************************************************/ #include "config.h" #include "sh7034.h" #include "kernel.h" #include "thread.h" #include "system.h" #include "debug.h" #include "panic.h" #include "adc.h" #include "string.h" #include "sprintf.h" #include "power.h" #include "powermgmt.h" #ifndef SIMULATOR static char power_stack[DEFAULT_STACK_SIZE]; static char power_thread_name[] = "power"; unsigned short power_history[POWER_HISTORY_LEN]; #ifdef HAVE_CHARGE_CTRL char power_message[POWER_MESSAGE_LEN] = ""; char charge_restart_level = CHARGE_RESTART_HI; #endif /* * This power thread maintains a history of battery voltage * and should, in the future, enable charging when it's needed * and power is available, and disable it when the battery is full. * Battery 'fullness' can be determined by the voltage drop, see: * * http://www.nimhbattery.com/nimhbattery-faq.htm questions 3 & 4 * http://www.powerpacks-uk.com/Charging%20NiMh%20Batteries.htm * http://www.angelfire.com/electronic/hayles/charge1.html (soft start idea) * http://www.powerstream.com/NiMH.htm (discouraging) * http://www.panasonic.com/industrial/battery/oem/images/pdf/nimhchar.pdf * http://www.duracell.com/oem/Pdf/others/nimh_5.pdf (discharging) * http://www.duracell.com/oem/Pdf/others/nimh_6.pdf (charging) * * Charging logic which we're starting with (by Linus, Hes, Bagder): * * 1) max 16 hrs charge time (just in negative delta detection fails) * 2) Stop at negative delta of 5 mins * 3) Stop at 15 mins of zero-delta or below * 4) minimum of 15 mins charge time before 2) is applied * 5) after end of charging, wait for charge go down 80% * before charging again if in 'no-use overnight charging mode' * and down to 10% if in 'fixed-location mains-powered usage mode' */ static void power_thread(void) { int i; int avg; #ifdef HAVE_CHARGE_CTRL int delta; int charged_time = 0; #endif while (1) { DEBUGF("power_thread woke up\n"); /* make POWER_AVG measurements and calculate an average of that to * reduce the effect of backlights/disk spinning/other variation */ avg = 0; for (i = 0; i < POWER_AVG; i++) { avg += adc_read(ADC_UNREG_POWER); sleep(15); } avg = avg / POWER_AVG; /* rotate the power history */ for (i = 0; i < POWER_HISTORY_LEN-1; i++) power_history[i] = power_history[i+1]; /* insert new value in the end, in decivolts 8-) */ power_history[POWER_HISTORY_LEN-1] = (avg * BATTERY_SCALE_FACTOR) / 10000; #ifdef HAVE_CHARGE_CTRL if (charger_inserted()) { if (charger_enabled) { /* charger inserted and enabled */ charged_time++; if (charged_time > CHARGE_MAX_TIME) { DEBUGF("power: charged_time > CHARGE_MAX_TIME, enough!\n"); /* have charged too long and deltaV detection did not work! */ charger_enable(false); snprintf(power_message, POWER_MESSAGE_LEN, "Chg tmout %d min", CHARGE_MAX_TIME); /* Perhaps we should disable charging for several hours from this point, just to be sure. */ } else { if (charged_time > CHARGE_MIN_TIME) { /* have charged continuously over the minimum charging time, * so we monitor for deltaV going negative. Multiply things * by 100 to get more accuracy without floating point arithmetic. * power_history[] contains decivolts. */ delta = 0; for (i = 0; i < CHARGE_END_NEGD; i++) delta += power_history[POWER_HISTORY_LEN-1-i]*100 - power_history[POWER_HISTORY_LEN-1-i-1]*100; delta = delta / CHARGE_END_NEGD; if (delta < -50) { /* delta < -0.3 V */ DEBUGF("power: short-term negative delta, enough!\n"); charger_enable(false); snprintf(power_message, POWER_MESSAGE_LEN, "end negd %d %dmin", delta, charged_time); } else { /* if we didn't disable the charger in the previous test, check for low positive delta */ delta = 0; for (i = 0; i < CHARGE_END_ZEROD; i++) delta += power_history[POWER_HISTORY_LEN-1-i]*100 - power_history[POWER_HISTORY_LEN-1-i-1]*100; delta = delta / CHARGE_END_ZEROD; if (delta <= 5) { /* delta of <= 0.005 V */ DEBUGF("power: long-term small positive delta, enough!\n"); charger_enable(false); snprintf(power_message, POWER_MESSAGE_LEN, "end lowd %d %dmin", delta, charged_time); } } } } } else { /* charged inserted but not enabled */ /* if battery is not full, enable charging */ if (battery_level() < charge_restart_level) { DEBUGF("power: charger inserted and battery not full, enabling\n"); charger_enable(true); charged_time = 0; snprintf(power_message, POWER_MESSAGE_LEN, "Chg started at %d%%", battery_level()); } } } else { /* charger not inserted */ if (charger_enabled) { /* charger not inserted but was enabled */ DEBUGF("power: charger disconnected, disabling\n"); charger_enable(false); snprintf(power_message, POWER_MESSAGE_LEN, "Charger disc"); } /* charger not inserted and disabled, so we're discharging */ } #endif /* HAVE_CHARGE_CTRL*/ /* sleep for roughly a minute */ sleep(HZ*(60-POWER_AVG*15)); } } void power_init(void) { /* init history to 0 */ memset(power_history, 0x00, sizeof(power_history)); #ifdef HAVE_CHARGE_CTRL snprintf(power_message, POWER_MESSAGE_LEN, "Powermgmt started"); #endif create_thread(power_thread, power_stack, sizeof(power_stack), power_thread_name); } #endif