ugfx/drivers/gadc/AT91SAM7/gadc_lld.c

103 lines
2.9 KiB
C
Raw Normal View History

/*
ChibiOS/GFX - Copyright (C) 2012, 2013
Joel Bodenmann aka Tectu <joel@unormal.org>
This file is part of ChibiOS/GFX.
ChibiOS/GFX is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
ChibiOS/GFX is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
/**
* @file include/gadc/lld/gadc_lld.c
* @brief GADC - Periodic ADC driver source file for the AT91SAM7 cpu.
*
* @defgroup Driver Driver
* @ingroup GADC
* @{
*/
#include "ch.h"
#include "hal.h"
#include "gfx.h"
#if GFX_USE_GADC
#include "gadc/lld/gadc_lld.h"
static ADCConversionGroup acg = {
FALSE, // circular
1, // num_channels
GADC_ISR_CompleteI, // end_cb
GADC_ISR_ErrorI, // error_cb
0, // channelselects
0, // trigger
0, // frequency
};
void gadc_lld_init(void) {
adcStart(&ADCD1, NULL);
}
size_t gadc_lld_samples_per_conversion(uint32_t physdev) {
size_t cnt;
int i;
/* The AT91SAM7 has AD0..7 - physdev is a bitmap of those channels */
for(cnt = 0, i = 0; i < 8; i++, physdev >>= 1)
if (physdev & 0x01)
cnt++;
return cnt;
}
void gadc_lld_start_timer(uint32_t physdev, uint32_t frequency) {
(void) physdev;
/**
* The AT91SAM7 ADC driver supports triggering the ADC using a timer without having to implement
* an interrupt handler for the timer. The driver also initialises the timer correctly for us.
* Because we aren't trapping the interrupt ourselves we can't increment GADC_Timer_Missed if an
* interrupt is missed.
*/
acg.frequency = frequency;
}
void gadc_lld_stop_timer(uint32_t physdev) {
(void) physdev;
if ((acg.trigger & ~ADC_TRIGGER_SOFTWARE) == ADC_TRIGGER_TIMER)
adcStop(&ADCD1);
}
void gadc_lld_adc_timerI(GadcLldTimerData *pgtd) {
/**
* We don't need to calculate num_channels because the AT91SAM7 ADC does this for us.
*/
acg.channelselects = pgtd->physdev;
acg.trigger = pgtd->now ? (ADC_TRIGGER_TIMER|ADC_TRIGGER_SOFTWARE) : ADC_TRIGGER_TIMER;
adcStartConversionI(&ADCD1, &acg, pgtd->buffer, pgtd->count);
/* Next time assume the same (still running) timer */
acg.frequency = 0;
}
void gadc_lld_adc_nontimerI(GadcLldNonTimerData *pgntd) {
/**
* We don't need to calculate num_channels because the AT91SAM7 ADC does this for us.
*/
acg.channelselects = pgntd->physdev;
acg.trigger = ADC_TRIGGER_SOFTWARE;
adcStartConversionI(&ADCD1, &acg, pgntd->buffer, 1);
}
#endif /* GFX_USE_GADC */
/** @} */