zephyr/drivers/adc/adc_ti_adc108s102.c

296 lines
7.0 KiB
C

/* adc-ti-adc108s102.c - TI's ADC 108s102 driver implementation */
/*
* Copyright (c) 2015 Intel Corporation
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include <nanokernel.h>
#include <misc/util.h>
#include <string.h>
#include <init.h>
#include "adc_ti_adc108s102.h"
#ifndef CONFIG_ADC_DEBUG
#define DBG(...) { ; }
#else
#if defined(CONFIG_STDOUT_CONSOLE)
#include <stdio.h>
#define DBG printf
#else
#include <misc/printk.h>
#define DBG printk
#endif /* CONFIG_STDOUT_CONSOLE */
#endif /* CONFIG_ADC_DEBUG */
static void _ti_adc108s102_sampling(int data, int unused)
{
struct device *dev = INT_TO_POINTER(data);
struct ti_adc108s102_data *adc = dev->driver_data;
ARG_UNUSED(unused);
DBG("Sampling!\n");
/* SPI deals with uint8_t buffers so multiplying by 2 the length */
spi_transceive(adc->spi,
(uint8_t *) adc->cmd_buffer,
adc->cmd_buf_len*2,
(uint8_t *) adc->sampling_buffer,
adc->sampling_buf_len*2);
}
static void _ti_adc108s102_completed(struct device *dev,
enum adc_callback_type cb_type)
{
struct ti_adc108s102_data *adc = dev->driver_data;
adc->seq_table = NULL;
adc->cb(dev, cb_type);
}
static inline void _ti_adc108s102_handle_result(struct device *dev)
{
struct ti_adc108s102_data *adc = dev->driver_data;
struct adc_seq_table *seq_table = adc->seq_table;
struct ti_adc108s102_chan *chan;
struct adc_seq_entry *entry;
uint32_t s_i, i;
DBG("_ti_adc108s102_handle_result()");
for (i = 0, s_i = 1; i < seq_table->num_entries; i++, s_i++) {
entry = &seq_table->entries[i];
chan = &adc->chans[entry->channel_id];
if (entry->buffer_length - chan->buf_idx == 0) {
continue;
}
*((uint16_t *)entry->buffer+chan->buf_idx) =
sys_be16_to_cpu(adc->sampling_buffer[s_i]);
chan->buf_idx += 2;
}
}
static int32_t _ti_adc108s102_prepare(struct device *dev)
{
struct ti_adc108s102_data *adc = dev->driver_data;
struct adc_seq_table *seq_table = adc->seq_table;
struct ti_adc108s102_chan *chan;
int32_t sampling_delay = 0;
uint32_t i;
adc->cmd_buf_len = 0;
adc->sampling_buf_len = 1;
for (i = 0; i < seq_table->num_entries; i++) {
struct adc_seq_entry *entry = &seq_table->entries[i];
/* No more space in the buffer? */
chan = &adc->chans[entry->channel_id];
if (entry->buffer_length - chan->buf_idx == 0) {
continue;
}
adc->cmd_buffer[adc->cmd_buf_len] =
ADC108S102_CHANNEL_CMD(entry->channel_id);
adc->cmd_buf_len++;
adc->sampling_buf_len++;
sampling_delay = entry->sampling_delay;
}
if (adc->cmd_buf_len == 0) {
/* We are done */
_ti_adc108s102_completed(dev, ADC_CB_DONE);
return 0;
}
/* dummy cmd byte */
adc->cmd_buffer[adc->cmd_buf_len] = 0;
adc->cmd_buf_len++;
/* 64bits timestamp */
adc->sampling_buf_len += 4;
DBG("ADC108S102 is prepared...");
return sampling_delay;
}
static inline void _ti_adc108s102_run_with_delay(struct device *dev,
int32_t delay)
{
struct ti_adc108s102_data *adc = dev->driver_data;
fiber_delayed_start(adc->sampling_stack,
ADC108S102_SAMPLING_STACK_SIZE,
_ti_adc108s102_sampling,
POINTER_TO_INT(dev), 0,
0, 0, delay);
}
static void _ti_adc108s102_spi_cb(struct device *spi_dev,
enum spi_cb_type cb_type,
void *user_data)
{
struct device *dev = user_data;
int32_t delay;
DBG("_ti_adc108s102_spi_cb(%d)\n", cb_type);
switch (cb_type) {
case SPI_CB_WRITE: /* fall through */
case SPI_CB_READ: /* fall through */
case SPI_CB_TRANSCEIVE:
_ti_adc108s102_handle_result(dev);
delay = _ti_adc108s102_prepare(dev);
_ti_adc108s102_run_with_delay(dev, delay);
break;
case SPI_CB_ERROR: /* fall through */
default:
_ti_adc108s102_completed(dev, ADC_CB_ERROR);
break;
}
}
static void ti_adc108s102_enable(struct device *dev)
{
/*
* There is nothing to be done. If there is no sampling going on,
* the chip will put itself on power-saving mode (that is because
* SPI will release CS)
*/
}
static void ti_adc108s102_disable(struct device *dev)
{
/* Same issue as with ti_adc108s102_enable() */
}
static void ti_adc108s102_set_callback(struct device *dev, adc_callback_t cb)
{
struct ti_adc108s102_data *adc = dev->driver_data;
adc->cb = cb;
}
static inline int _verify_entries(struct adc_seq_table *seq_table)
{
struct adc_seq_entry *entry;
uint32_t chans_set = 0;
int i;
for (i = 0; i < seq_table->num_entries; i++) {
entry = &seq_table->entries[i];
if (entry->sampling_delay <= 0 ||
entry->channel_id > ADC108S102_CHANNELS) {
return 0;
}
if (!entry->buffer_length) {
continue;
}
chans_set++;
}
return chans_set;
}
static int ti_adc108s102_read(struct device *dev,
struct adc_seq_table *seq_table)
{
struct ti_adc108s102_config *config = dev->config->config_info;
struct ti_adc108s102_data *adc = dev->driver_data;
struct spi_config spi_conf;
spi_conf.config = config->spi_config_flags;
spi_conf.max_sys_freq = config->spi_freq;
spi_conf.callback = _ti_adc108s102_spi_cb;
if (spi_configure(adc->spi, &spi_conf, dev)) {
return DEV_FAIL;
}
if (spi_slave_select(adc->spi, config->spi_slave)) {
return DEV_FAIL;
}
/* Resetting all internal channel data */
memset(adc->chans, 0, ADC108S102_CHANNELS_SIZE);
if (_verify_entries(seq_table) == 0) {
return DEV_INVALID_CONF;
}
adc->seq_table = seq_table;
/* Requesting sampling right away */
_ti_adc108s102_prepare(dev);
_ti_adc108s102_sampling(POINTER_TO_INT(dev), 0);
return DEV_OK;
}
struct adc_driver_api ti_adc108s102_api = {
.enable = ti_adc108s102_enable,
.disable = ti_adc108s102_disable,
.set_callback = ti_adc108s102_set_callback,
.read = ti_adc108s102_read,
};
int ti_adc108s102_init(struct device *dev)
{
struct ti_adc108s102_config *config = dev->config->config_info;
struct ti_adc108s102_data *adc = dev->driver_data;
adc->spi = device_get_binding((char *)config->spi_port);
if (!adc->spi) {
return DEV_NOT_CONFIG;
}
DBG("ADC108s102 initialized\n");
dev->driver_api = &ti_adc108s102_api;
return DEV_OK;
}
#ifdef CONFIG_ADC_TI_ADC108S102_0
struct ti_adc108s102_data adc108s102_0_data;
struct ti_adc108s102_config adc108s102_0_config = {
.spi_port = CONFIG_ADC_TI_ADC108S102_0_SPI_PORT_NAME,
.spi_config_flags = CONFIG_ADC_TI_ADC108S102_0_SPI_CONFIGURATION,
.spi_freq = CONFIG_ADC_TI_ADC108S102_0_SPI_MAX_FREQ,
.spi_slave = CONFIG_ADC_TI_ADC108S102_0_SPI_SLAVE,
};
DECLARE_DEVICE_INIT_CONFIG(adc108s102_0, CONFIG_ADC_TI_ADC108S102_0_DRV_NAME,
ti_adc108s102_init, &adc108s102_0_config);
SYS_DEFINE_DEVICE(adc108s102_0, &adc108s102_0_data, SECONDARY,
CONFIG_ADC_TI_ADC108S102_INIT_PRIORITY);
#endif /* CONFIG_ADC_TI_ADC108S102_0 */