Johannes Stratmann / mbed-dev

added prescaler for 16 bit pwm in LPC1347 target

Fork of mbed-dev by mbed official

targets/hal/TARGET_Atmel/TARGET_SAM_CortexM0P/sercom_dma.c@64:41a834223ea3, 2016-02-15 (annotated)

Committer:
mbed_official
Date:
Mon Feb 15 10:00:10 2016 +0000
Revision:
64:41a834223ea3
Parent:
15:a81a8d6c1dfe 
Synchronized with git revision e641fd47cf2a6bafdbe87c743a39772f73edcbe7



Full URL: https://github.com/mbedmicro/mbed/commit/e641fd47cf2a6bafdbe87c743a39772f73edcbe7/



Fixed GCC Compiler warnings

Who changed what in which revision?

UserRevisionLine numberNew contents of line
mbed_official 15:a81a8d6c1dfe 1 /* mbed Microcontroller Library
mbed_official 15:a81a8d6c1dfe 2 * Copyright (c) 2006-2015 ARM Limited
mbed_official 15:a81a8d6c1dfe 3 *
mbed_official 15:a81a8d6c1dfe 4 * Licensed under the Apache License, Version 2.0 (the "License");
mbed_official 15:a81a8d6c1dfe 5 * you may not use this file except in compliance with the License.
mbed_official 15:a81a8d6c1dfe 6 * You may obtain a copy of the License at
mbed_official 15:a81a8d6c1dfe 7 *
mbed_official 15:a81a8d6c1dfe 8 * http://www.apache.org/licenses/LICENSE-2.0
mbed_official 15:a81a8d6c1dfe 9 *
mbed_official 15:a81a8d6c1dfe 10 * Unless required by applicable law or agreed to in writing, software
mbed_official 15:a81a8d6c1dfe 11 * distributed under the License is distributed on an "AS IS" BASIS,
mbed_official 15:a81a8d6c1dfe 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
mbed_official 15:a81a8d6c1dfe 13 * See the License for the specific language governing permissions and
mbed_official 15:a81a8d6c1dfe 14 * limitations under the License.
mbed_official 15:a81a8d6c1dfe 15 */
mbed_official 15:a81a8d6c1dfe 16 #include "mbed_assert.h"
mbed_official 15:a81a8d6c1dfe 17
mbed_official 15:a81a8d6c1dfe 18 #include "cmsis.h"
mbed_official 15:a81a8d6c1dfe 19 #include "sercom.h"
mbed_official 15:a81a8d6c1dfe 20 #include "dma_api.h"
mbed_official 15:a81a8d6c1dfe 21 #include "dma_api_HAL.h"
mbed_official 15:a81a8d6c1dfe 22 #include "sercom_dma.h"
mbed_official 15:a81a8d6c1dfe 23
mbed_official 15:a81a8d6c1dfe 24 static struct sercom_dma sercom_channels[SERCOM_INST_NUM] = {{0}};
mbed_official 15:a81a8d6c1dfe 25
mbed_official 15:a81a8d6c1dfe 26 /** Allocate a channel for TX
mbed_official 15:a81a8d6c1dfe 27 *
mbed_official 15:a81a8d6c1dfe 28 * @param[in] sercom_index index of sercom instance
mbed_official 15:a81a8d6c1dfe 29 * @param[out] tx_id pointer to channel id
mbed_official 15:a81a8d6c1dfe 30 * @return allocated channel id
mbed_official 15:a81a8d6c1dfe 31 */
mbed_official 15:a81a8d6c1dfe 32 uint8_t sercom_setup_tx_channel(uint8_t sercom_index, uint8_t *tx_id)
mbed_official 15:a81a8d6c1dfe 33 {
mbed_official 15:a81a8d6c1dfe 34 if (sercom_channels[sercom_index].tx_status & DMA_ALLOCATED) {
mbed_official 15:a81a8d6c1dfe 35 *tx_id = sercom_channels[sercom_index].tx_channel_id;
mbed_official 15:a81a8d6c1dfe 36 } else {
mbed_official 15:a81a8d6c1dfe 37 /* Try to allocate a channel */
mbed_official 15:a81a8d6c1dfe 38 sercom_channels[sercom_index].tx_channel_id = dma_channel_allocate(DMA_CAP_NONE);
mbed_official 15:a81a8d6c1dfe 39 if (sercom_channels[sercom_index].tx_channel_id != (uint8_t)DMA_ERROR_OUT_OF_CHANNELS) {
mbed_official 15:a81a8d6c1dfe 40 *tx_id = sercom_channels[sercom_index].tx_channel_id;
mbed_official 15:a81a8d6c1dfe 41 sercom_channels[sercom_index].tx_status = DMA_ALLOCATED;
mbed_official 15:a81a8d6c1dfe 42 } else {
mbed_official 15:a81a8d6c1dfe 43 /* Couldn't find a channel */
mbed_official 64:41a834223ea3 44 return (uint8_t)DMA_ERROR_OUT_OF_CHANNELS;
mbed_official 15:a81a8d6c1dfe 45 }
mbed_official 15:a81a8d6c1dfe 46 }
mbed_official 15:a81a8d6c1dfe 47 return *tx_id;
mbed_official 15:a81a8d6c1dfe 48 }
mbed_official 15:a81a8d6c1dfe 49
mbed_official 15:a81a8d6c1dfe 50 /** Allocate a channel for RX
mbed_official 15:a81a8d6c1dfe 51 *
mbed_official 15:a81a8d6c1dfe 52 * @param[in] sercom_index index of sercom instance
mbed_official 15:a81a8d6c1dfe 53 * @param[out] rx_id pointer to channel id
mbed_official 15:a81a8d6c1dfe 54 * @return allocated channel id
mbed_official 15:a81a8d6c1dfe 55 */
mbed_official 15:a81a8d6c1dfe 56 uint8_t sercom_setup_rx_channel(uint8_t sercom_index, uint8_t *rx_id)
mbed_official 15:a81a8d6c1dfe 57 {
mbed_official 15:a81a8d6c1dfe 58 if (sercom_channels[sercom_index].rx_status & DMA_ALLOCATED) {
mbed_official 15:a81a8d6c1dfe 59 *rx_id = sercom_channels[sercom_index].rx_channel_id;
mbed_official 15:a81a8d6c1dfe 60 } else {
mbed_official 15:a81a8d6c1dfe 61 /* Try to allocate a channel */
mbed_official 15:a81a8d6c1dfe 62 sercom_channels[sercom_index].rx_channel_id = dma_channel_allocate(DMA_CAP_NONE);
mbed_official 15:a81a8d6c1dfe 63 if (sercom_channels[sercom_index].rx_channel_id != (uint8_t)DMA_ERROR_OUT_OF_CHANNELS) {
mbed_official 15:a81a8d6c1dfe 64 *rx_id = sercom_channels[sercom_index].rx_channel_id;
mbed_official 15:a81a8d6c1dfe 65 sercom_channels[sercom_index].rx_status = DMA_ALLOCATED;
mbed_official 15:a81a8d6c1dfe 66 } else {
mbed_official 15:a81a8d6c1dfe 67 /* Couldn't find a channel */
mbed_official 64:41a834223ea3 68 return (uint8_t)DMA_ERROR_OUT_OF_CHANNELS;
mbed_official 15:a81a8d6c1dfe 69 }
mbed_official 15:a81a8d6c1dfe 70 }
mbed_official 15:a81a8d6c1dfe 71 return *rx_id;
mbed_official 15:a81a8d6c1dfe 72 }
mbed_official 15:a81a8d6c1dfe 73
mbed_official 15:a81a8d6c1dfe 74 /** Release DMA channels if allocated
mbed_official 15:a81a8d6c1dfe 75 *
mbed_official 15:a81a8d6c1dfe 76 * @param[in] sercom_index index of sercom instance
mbed_official 15:a81a8d6c1dfe 77 * @return void
mbed_official 15:a81a8d6c1dfe 78 */
mbed_official 15:a81a8d6c1dfe 79 void sercom_release_channel(uint8_t sercom_index)
mbed_official 15:a81a8d6c1dfe 80 {
mbed_official 15:a81a8d6c1dfe 81 if (sercom_channels[sercom_index].rx_status & DMA_ALLOCATED) {
mbed_official 15:a81a8d6c1dfe 82 if (0 == dma_channel_free(sercom_channels[sercom_index].rx_channel_id)) {
mbed_official 15:a81a8d6c1dfe 83 sercom_channels[sercom_index].rx_status = DMA_NOT_USED;
mbed_official 15:a81a8d6c1dfe 84 }
mbed_official 15:a81a8d6c1dfe 85 }
mbed_official 15:a81a8d6c1dfe 86 if (sercom_channels[sercom_index].tx_status & DMA_ALLOCATED) {
mbed_official 15:a81a8d6c1dfe 87 if (0 == dma_channel_free(sercom_channels[sercom_index].tx_channel_id)) {
mbed_official 15:a81a8d6c1dfe 88 sercom_channels[sercom_index].tx_status = DMA_NOT_USED;
mbed_official 15:a81a8d6c1dfe 89 }
mbed_official 15:a81a8d6c1dfe 90 }
mbed_official 15:a81a8d6c1dfe 91 }