coreboot-libre-fam15h-rdimm/3rdparty/chromeec/chip/nrf51/ppi.c

70 lines
1.5 KiB
C

/* Copyright 2016 The Chromium OS Authors. All rights reserved.
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#include "ppi.h"
#include "registers.h"
#include "util.h"
#define NRF51_PPI_FIRST_PP_CH NRF51_PPI_CH_TIMER0_CC0__RADIO_TXEN
#define NRF51_PPI_LAST_PP_CH NRF51_PPI_CH_RTC0_COMPARE0__TIMER0_START
static uint32_t channels_in_use;
static uint32_t channel_groups_in_use;
int ppi_request_pre_programmed_channel(int ppi_chan)
{
ASSERT(ppi_chan >= NRF51_PPI_FIRST_PP_CH &&
ppi_chan <= NRF51_PPI_LAST_PP_CH);
if (channels_in_use & BIT(ppi_chan))
return EC_ERROR_BUSY;
channels_in_use |= BIT(ppi_chan);
return EC_SUCCESS;
}
int ppi_request_channel(int *ppi_chan)
{
int chan;
for (chan = 0; chan < NRF51_PPI_NUM_PROGRAMMABLE_CHANNELS; chan++)
if ((channels_in_use & BIT(chan)) == 0)
break;
if (chan == NRF51_PPI_NUM_PROGRAMMABLE_CHANNELS)
return EC_ERROR_BUSY;
channels_in_use |= BIT(chan);
*ppi_chan = chan;
return EC_SUCCESS;
}
void ppi_release_channel(int ppi_chan)
{
channels_in_use &= ~BIT(ppi_chan);
}
void ppi_release_group(int ppi_group)
{
channel_groups_in_use &= ~BIT(ppi_group);
}
int ppi_request_group(int *ppi_group)
{
int group;
for (group = 0; group < NRF51_PPI_NUM_GROUPS; group++)
if ((channel_groups_in_use & BIT(group)) == 0)
break;
if (group == NRF51_PPI_NUM_GROUPS)
return EC_ERROR_BUSY;
channel_groups_in_use |= BIT(group);
*ppi_group = group;
return EC_SUCCESS;
}