blob: 440948645c6f0e6c137d512c006257cbb25210cb [file] [log] [blame]
/*
* Copyright (c) 2017 comsuisse AG
*
* SPDX-License-Identifier: Apache-2.0
*/
#define DT_DRV_COMPAT atmel_sam_ssc
/** @file
* @brief I2S bus (SSC) driver for Atmel SAM MCU family.
*
* Limitations:
* - TX and RX path share a common bit clock divider and as a result they cannot
* be configured independently. If RX and TX path are set to different bit
* clock frequencies the latter setting will quietly override the former.
* We should return an error in such a case.
* - DMA is used in simple single block transfer mode and as such is not able
* to handle high speed data. To support higher transfer speeds the DMA
* linked list mode should be used.
*/
#include <errno.h>
#include <string.h>
#include <zephyr/sys/__assert.h>
#include <zephyr/kernel.h>
#include <zephyr/device.h>
#include <zephyr/init.h>
#include <zephyr/drivers/dma.h>
#include <zephyr/drivers/i2s.h>
#include <zephyr/drivers/pinctrl.h>
#include <soc.h>
#define LOG_DOMAIN dev_i2s_sam_ssc
#define LOG_LEVEL CONFIG_I2S_LOG_LEVEL
#include <zephyr/logging/log.h>
LOG_MODULE_REGISTER(LOG_DOMAIN);
#if __DCACHE_PRESENT == 1
#define DCACHE_INVALIDATE(addr, size) \
SCB_InvalidateDCache_by_Addr((uint32_t *)addr, size)
#define DCACHE_CLEAN(addr, size) \
SCB_CleanDCache_by_Addr((uint32_t *)addr, size)
#else
#define DCACHE_INVALIDATE(addr, size) {; }
#define DCACHE_CLEAN(addr, size) {; }
#endif
#define SAM_SSC_WORD_SIZE_BITS_MIN 2
#define SAM_SSC_WORD_SIZE_BITS_MAX 32
#define SAM_SSC_WORD_PER_FRAME_MIN 1
#define SAM_SSC_WORD_PER_FRAME_MAX 16
struct queue_item {
void *mem_block;
size_t size;
};
/* Minimal ring buffer implementation */
struct ring_buf {
struct queue_item *buf;
uint16_t len;
uint16_t head;
uint16_t tail;
};
/* Device constant configuration parameters */
struct i2s_sam_dev_cfg {
const struct device *dev_dma;
Ssc *regs;
void (*irq_config)(void);
const struct pinctrl_dev_config *pcfg;
uint8_t periph_id;
uint8_t irq_id;
};
struct stream {
int32_t state;
struct k_sem sem;
uint32_t dma_channel;
uint8_t dma_perid;
uint8_t word_size_bytes;
bool last_block;
struct i2s_config cfg;
struct ring_buf mem_block_queue;
void *mem_block;
int (*stream_start)(struct stream *, Ssc *const,
const struct device *);
void (*stream_disable)(struct stream *, Ssc *const,
const struct device *);
void (*queue_drop)(struct stream *);
int (*set_data_format)(const struct i2s_sam_dev_cfg *const,
const struct i2s_config *);
};
/* Device run time data */
struct i2s_sam_dev_data {
struct stream rx;
struct stream tx;
};
#define MODULO_INC(val, max) { val = (++val < max) ? val : 0; }
static const struct device *get_dev_from_dma_channel(uint32_t dma_channel);
static void dma_rx_callback(const struct device *, void *, uint32_t, int);
static void dma_tx_callback(const struct device *, void *, uint32_t, int);
static void rx_stream_disable(struct stream *, Ssc *const,
const struct device *);
static void tx_stream_disable(struct stream *, Ssc *const,
const struct device *);
/*
* Get data from the queue
*/
static int queue_get(struct ring_buf *rb, void **mem_block, size_t *size)
{
unsigned int key;
key = irq_lock();
if (rb->tail == rb->head) {
/* Ring buffer is empty */
irq_unlock(key);
return -ENOMEM;
}
*mem_block = rb->buf[rb->tail].mem_block;
*size = rb->buf[rb->tail].size;
MODULO_INC(rb->tail, rb->len);
irq_unlock(key);
return 0;
}
/*
* Put data in the queue
*/
static int queue_put(struct ring_buf *rb, void *mem_block, size_t size)
{
uint16_t head_next;
unsigned int key;
key = irq_lock();
head_next = rb->head;
MODULO_INC(head_next, rb->len);
if (head_next == rb->tail) {
/* Ring buffer is full */
irq_unlock(key);
return -ENOMEM;
}
rb->buf[rb->head].mem_block = mem_block;
rb->buf[rb->head].size = size;
rb->head = head_next;
irq_unlock(key);
return 0;
}
static int reload_dma(const struct device *dev_dma, uint32_t channel,
void *src, void *dst, size_t size)
{
int ret;
ret = dma_reload(dev_dma, channel, (uint32_t)src, (uint32_t)dst, size);
if (ret < 0) {
return ret;
}
ret = dma_start(dev_dma, channel);
return ret;
}
static int start_dma(const struct device *dev_dma, uint32_t channel,
struct dma_config *cfg, void *src, void *dst,
uint32_t blk_size)
{
struct dma_block_config blk_cfg;
int ret;
(void)memset(&blk_cfg, 0, sizeof(blk_cfg));
blk_cfg.block_size = blk_size;
blk_cfg.source_address = (uint32_t)src;
blk_cfg.dest_address = (uint32_t)dst;
cfg->head_block = &blk_cfg;
ret = dma_config(dev_dma, channel, cfg);
if (ret < 0) {
return ret;
}
ret = dma_start(dev_dma, channel);
return ret;
}
/* This function is executed in the interrupt context */
static void dma_rx_callback(const struct device *dma_dev, void *user_data,
uint32_t channel, int status)
{
const struct device *dev = get_dev_from_dma_channel(channel);
const struct i2s_sam_dev_cfg *const dev_cfg = dev->config;
struct i2s_sam_dev_data *const dev_data = dev->data;
Ssc *const ssc = dev_cfg->regs;
struct stream *stream = &dev_data->rx;
int ret;
ARG_UNUSED(user_data);
__ASSERT_NO_MSG(stream->mem_block != NULL);
/* Stop reception if there was an error */
if (stream->state == I2S_STATE_ERROR) {
goto rx_disable;
}
/* All block data received */
ret = queue_put(&stream->mem_block_queue, stream->mem_block,
stream->cfg.block_size);
if (ret < 0) {
stream->state = I2S_STATE_ERROR;
goto rx_disable;
}
stream->mem_block = NULL;
k_sem_give(&stream->sem);
/* Stop reception if we were requested */
if (stream->state == I2S_STATE_STOPPING) {
stream->state = I2S_STATE_READY;
goto rx_disable;
}
/* Prepare to receive the next data block */
ret = k_mem_slab_alloc(stream->cfg.mem_slab, &stream->mem_block,
K_NO_WAIT);
if (ret < 0) {
stream->state = I2S_STATE_ERROR;
goto rx_disable;
}
/* Assure cache coherency before DMA write operation */
DCACHE_INVALIDATE(stream->mem_block, stream->cfg.block_size);
ret = reload_dma(dev_cfg->dev_dma, stream->dma_channel,
(void *)&(ssc->SSC_RHR), stream->mem_block,
stream->cfg.block_size);
if (ret < 0) {
LOG_DBG("Failed to reload RX DMA transfer: %d", ret);
goto rx_disable;
}
return;
rx_disable:
rx_stream_disable(stream, ssc, dev_cfg->dev_dma);
}
/* This function is executed in the interrupt context */
static void dma_tx_callback(const struct device *dma_dev, void *user_data,
uint32_t channel, int status)
{
const struct device *dev = get_dev_from_dma_channel(channel);
const struct i2s_sam_dev_cfg *const dev_cfg = dev->config;
struct i2s_sam_dev_data *const dev_data = dev->data;
Ssc *const ssc = dev_cfg->regs;
struct stream *stream = &dev_data->tx;
size_t mem_block_size;
int ret;
ARG_UNUSED(user_data);
__ASSERT_NO_MSG(stream->mem_block != NULL);
/* All block data sent */
k_mem_slab_free(stream->cfg.mem_slab, &stream->mem_block);
stream->mem_block = NULL;
/* Stop transmission if there was an error */
if (stream->state == I2S_STATE_ERROR) {
LOG_DBG("TX error detected");
goto tx_disable;
}
/* Stop transmission if we were requested */
if (stream->last_block) {
stream->state = I2S_STATE_READY;
goto tx_disable;
}
/* Prepare to send the next data block */
ret = queue_get(&stream->mem_block_queue, &stream->mem_block,
&mem_block_size);
if (ret < 0) {
if (stream->state == I2S_STATE_STOPPING) {
stream->state = I2S_STATE_READY;
} else {
stream->state = I2S_STATE_ERROR;
}
goto tx_disable;
}
k_sem_give(&stream->sem);
/* Assure cache coherency before DMA read operation */
DCACHE_CLEAN(stream->mem_block, mem_block_size);
ret = reload_dma(dev_cfg->dev_dma, stream->dma_channel,
stream->mem_block, (void *)&(ssc->SSC_THR),
mem_block_size);
if (ret < 0) {
LOG_DBG("Failed to reload TX DMA transfer: %d", ret);
goto tx_disable;
}
return;
tx_disable:
tx_stream_disable(stream, ssc, dev_cfg->dev_dma);
}
static int set_rx_data_format(const struct i2s_sam_dev_cfg *const dev_cfg,
const struct i2s_config *i2s_cfg)
{
Ssc *const ssc = dev_cfg->regs;
const bool pin_rk_en = IS_ENABLED(CONFIG_I2S_SAM_SSC_0_PIN_RK_EN);
const bool pin_rf_en = IS_ENABLED(CONFIG_I2S_SAM_SSC_0_PIN_RF_EN);
uint8_t word_size_bits = i2s_cfg->word_size;
uint8_t num_words = i2s_cfg->channels;
uint8_t fslen = 0U;
uint32_t ssc_rcmr = 0U;
uint32_t ssc_rfmr = 0U;
bool frame_clk_master = !(i2s_cfg->options & I2S_OPT_FRAME_CLK_SLAVE);
switch (i2s_cfg->format & I2S_FMT_DATA_FORMAT_MASK) {
case I2S_FMT_DATA_FORMAT_I2S:
num_words = 2U;
fslen = word_size_bits - 1;
ssc_rcmr = SSC_RCMR_CKI
| (pin_rf_en ? SSC_RCMR_START_RF_FALLING : 0)
| SSC_RCMR_STTDLY(1);
ssc_rfmr = (pin_rf_en && frame_clk_master
? SSC_RFMR_FSOS_NEGATIVE : SSC_RFMR_FSOS_NONE);
break;
case I2S_FMT_DATA_FORMAT_PCM_SHORT:
ssc_rcmr = (pin_rf_en ? SSC_RCMR_START_RF_FALLING : 0)
| SSC_RCMR_STTDLY(0);
ssc_rfmr = (pin_rf_en && frame_clk_master
? SSC_RFMR_FSOS_POSITIVE : SSC_RFMR_FSOS_NONE);
break;
case I2S_FMT_DATA_FORMAT_PCM_LONG:
fslen = num_words * word_size_bits / 2U - 1;
ssc_rcmr = (pin_rf_en ? SSC_RCMR_START_RF_RISING : 0)
| SSC_RCMR_STTDLY(0);
ssc_rfmr = (pin_rf_en && frame_clk_master
? SSC_RFMR_FSOS_POSITIVE : SSC_RFMR_FSOS_NONE);
break;
case I2S_FMT_DATA_FORMAT_LEFT_JUSTIFIED:
fslen = num_words * word_size_bits / 2U - 1;
ssc_rcmr = SSC_RCMR_CKI
| (pin_rf_en ? SSC_RCMR_START_RF_RISING : 0)
| SSC_RCMR_STTDLY(0);
ssc_rfmr = (pin_rf_en && frame_clk_master
? SSC_RFMR_FSOS_POSITIVE : SSC_RFMR_FSOS_NONE);
break;
default:
LOG_ERR("Unsupported I2S data format");
return -EINVAL;
}
if (pin_rk_en) {
ssc_rcmr |= ((i2s_cfg->options & I2S_OPT_BIT_CLK_SLAVE)
? SSC_RCMR_CKS_RK : SSC_RCMR_CKS_MCK)
| ((i2s_cfg->options & I2S_OPT_BIT_CLK_GATED)
? SSC_RCMR_CKO_TRANSFER : SSC_RCMR_CKO_CONTINUOUS);
} else {
ssc_rcmr |= SSC_RCMR_CKS_TK
| SSC_RCMR_CKO_NONE;
}
/* SSC_RCMR.PERIOD bit filed does not support setting the
* frame period with one bit resolution. In case the required
* frame period is an odd number set it to be one bit longer.
*/
ssc_rcmr |= (pin_rf_en ? 0 : SSC_RCMR_START_TRANSMIT)
| SSC_RCMR_PERIOD((num_words * word_size_bits + 1) / 2U - 1);
/* Receive Clock Mode Register */
ssc->SSC_RCMR = ssc_rcmr;
ssc_rfmr |= SSC_RFMR_DATLEN(word_size_bits - 1)
| ((i2s_cfg->format & I2S_FMT_DATA_ORDER_LSB)
? 0 : SSC_RFMR_MSBF)
| SSC_RFMR_DATNB(num_words - 1)
| SSC_RFMR_FSLEN(fslen)
| SSC_RFMR_FSLEN_EXT(fslen >> 4);
/* Receive Frame Mode Register */
ssc->SSC_RFMR = ssc_rfmr;
return 0;
}
static int set_tx_data_format(const struct i2s_sam_dev_cfg *const dev_cfg,
const struct i2s_config *i2s_cfg)
{
Ssc *const ssc = dev_cfg->regs;
uint8_t word_size_bits = i2s_cfg->word_size;
uint8_t num_words = i2s_cfg->channels;
uint8_t fslen = 0U;
uint32_t ssc_tcmr = 0U;
uint32_t ssc_tfmr = 0U;
switch (i2s_cfg->format & I2S_FMT_DATA_FORMAT_MASK) {
case I2S_FMT_DATA_FORMAT_I2S:
num_words = 2U;
fslen = word_size_bits - 1;
ssc_tcmr = SSC_TCMR_START_TF_FALLING
| SSC_TCMR_STTDLY(1);
ssc_tfmr = SSC_TFMR_FSOS_NEGATIVE;
break;
case I2S_FMT_DATA_FORMAT_PCM_SHORT:
ssc_tcmr = SSC_TCMR_CKI
| SSC_TCMR_START_TF_FALLING
| SSC_TCMR_STTDLY(0);
ssc_tfmr = SSC_TFMR_FSOS_POSITIVE;
break;
case I2S_FMT_DATA_FORMAT_PCM_LONG:
fslen = num_words * word_size_bits / 2U - 1;
ssc_tcmr = SSC_TCMR_CKI
| SSC_TCMR_START_TF_RISING
| SSC_TCMR_STTDLY(0);
ssc_tfmr = SSC_TFMR_FSOS_POSITIVE;
break;
case I2S_FMT_DATA_FORMAT_LEFT_JUSTIFIED:
fslen = num_words * word_size_bits / 2U - 1;
ssc_tcmr = SSC_TCMR_START_TF_RISING
| SSC_TCMR_STTDLY(0);
ssc_tfmr = SSC_TFMR_FSOS_POSITIVE;
break;
default:
LOG_ERR("Unsupported I2S data format");
return -EINVAL;
}
/* SSC_TCMR.PERIOD bit filed does not support setting the
* frame period with one bit resolution. In case the required
* frame period is an odd number set it to be one bit longer.
*/
ssc_tcmr |= ((i2s_cfg->options & I2S_OPT_BIT_CLK_SLAVE)
? SSC_TCMR_CKS_TK : SSC_TCMR_CKS_MCK)
| ((i2s_cfg->options & I2S_OPT_BIT_CLK_GATED)
? SSC_TCMR_CKO_TRANSFER : SSC_TCMR_CKO_CONTINUOUS)
| SSC_TCMR_PERIOD((num_words * word_size_bits + 1) / 2U - 1);
/* Transmit Clock Mode Register */
ssc->SSC_TCMR = ssc_tcmr;
if (i2s_cfg->options & I2S_OPT_FRAME_CLK_SLAVE) {
ssc_tfmr &= ~SSC_TFMR_FSOS_Msk;
ssc_tfmr |= SSC_TFMR_FSOS_NONE;
}
ssc_tfmr |= SSC_TFMR_DATLEN(word_size_bits - 1)
| ((i2s_cfg->format & I2S_FMT_DATA_ORDER_LSB)
? 0 : SSC_TFMR_MSBF)
| SSC_TFMR_DATNB(num_words - 1)
| SSC_TFMR_FSLEN(fslen)
| SSC_TFMR_FSLEN_EXT(fslen >> 4);
/* Transmit Frame Mode Register */
ssc->SSC_TFMR = ssc_tfmr;
return 0;
}
/* Calculate number of bytes required to store a word of bit_size length */
static uint8_t get_word_size_bytes(uint8_t bit_size)
{
uint8_t byte_size_min = (bit_size + 7) / 8U;
uint8_t byte_size;
byte_size = (byte_size_min == 3U) ? 4 : byte_size_min;
return byte_size;
}
static int bit_clock_set(Ssc *const ssc, uint32_t bit_clk_freq)
{
uint32_t clk_div = SOC_ATMEL_SAM_MCK_FREQ_HZ / bit_clk_freq / 2U;
if (clk_div == 0U || clk_div >= (1 << 12)) {
LOG_ERR("Invalid bit clock frequency");
return -EINVAL;
}
ssc->SSC_CMR = clk_div;
LOG_DBG("freq = %d", bit_clk_freq);
return 0;
}
static const struct i2s_config *i2s_sam_config_get(const struct device *dev,
enum i2s_dir dir)
{
struct i2s_sam_dev_data *const dev_data = dev->data;
struct stream *stream;
if (dir == I2S_DIR_RX) {
stream = &dev_data->rx;
} else {
stream = &dev_data->tx;
}
if (stream->state == I2S_STATE_NOT_READY) {
return NULL;
}
return &stream->cfg;
}
static int i2s_sam_configure(const struct device *dev, enum i2s_dir dir,
const struct i2s_config *i2s_cfg)
{
const struct i2s_sam_dev_cfg *const dev_cfg = dev->config;
struct i2s_sam_dev_data *const dev_data = dev->data;
Ssc *const ssc = dev_cfg->regs;
uint8_t num_words = i2s_cfg->channels;
uint8_t word_size_bits = i2s_cfg->word_size;
uint32_t bit_clk_freq;
struct stream *stream;
int ret;
if (dir == I2S_DIR_RX) {
stream = &dev_data->rx;
} else if (dir == I2S_DIR_TX) {
stream = &dev_data->tx;
} else if (dir == I2S_DIR_BOTH) {
return -ENOSYS;
} else {
LOG_ERR("Either RX or TX direction must be selected");
return -EINVAL;
}
if (stream->state != I2S_STATE_NOT_READY &&
stream->state != I2S_STATE_READY) {
LOG_ERR("invalid state");
return -EINVAL;
}
if (i2s_cfg->frame_clk_freq == 0U) {
stream->queue_drop(stream);
(void)memset(&stream->cfg, 0, sizeof(struct i2s_config));
stream->state = I2S_STATE_NOT_READY;
return 0;
}
if (i2s_cfg->format & I2S_FMT_FRAME_CLK_INV) {
LOG_ERR("Frame clock inversion is not implemented");
LOG_ERR("Please submit a patch");
return -EINVAL;
}
if (i2s_cfg->format & I2S_FMT_BIT_CLK_INV) {
LOG_ERR("Bit clock inversion is not implemented");
LOG_ERR("Please submit a patch");
return -EINVAL;
}
if (word_size_bits < SAM_SSC_WORD_SIZE_BITS_MIN ||
word_size_bits > SAM_SSC_WORD_SIZE_BITS_MAX) {
LOG_ERR("Unsupported I2S word size");
return -EINVAL;
}
if (num_words < SAM_SSC_WORD_PER_FRAME_MIN ||
num_words > SAM_SSC_WORD_PER_FRAME_MAX) {
LOG_ERR("Unsupported words per frame number");
return -EINVAL;
}
memcpy(&stream->cfg, i2s_cfg, sizeof(struct i2s_config));
bit_clk_freq = i2s_cfg->frame_clk_freq * word_size_bits * num_words;
ret = bit_clock_set(ssc, bit_clk_freq);
if (ret < 0) {
return ret;
}
ret = stream->set_data_format(dev_cfg, i2s_cfg);
if (ret < 0) {
return ret;
}
/* Set up DMA channel parameters */
stream->word_size_bytes = get_word_size_bytes(word_size_bits);
if (i2s_cfg->options & I2S_OPT_LOOPBACK) {
ssc->SSC_RFMR |= SSC_RFMR_LOOP;
}
stream->state = I2S_STATE_READY;
return 0;
}
static int rx_stream_start(struct stream *stream, Ssc *const ssc,
const struct device *dev_dma)
{
int ret;
ret = k_mem_slab_alloc(stream->cfg.mem_slab, &stream->mem_block,
K_NO_WAIT);
if (ret < 0) {
return ret;
}
/* Workaround for a hardware bug: DMA engine will read first data
* item even if SSC_SR.RXEN (Receive Enable) is not set. An extra read
* before enabling DMA engine sets hardware FSM in the correct state.
*/
(void)ssc->SSC_RHR;
struct dma_config dma_cfg = {
.source_data_size = stream->word_size_bytes,
.dest_data_size = stream->word_size_bytes,
.block_count = 1,
.dma_slot = stream->dma_perid,
.channel_direction = PERIPHERAL_TO_MEMORY,
.source_burst_length = 1,
.dest_burst_length = 1,
.dma_callback = dma_rx_callback,
};
ret = start_dma(dev_dma, stream->dma_channel, &dma_cfg,
(void *)&(ssc->SSC_RHR), stream->mem_block,
stream->cfg.block_size);
if (ret < 0) {
LOG_ERR("Failed to start RX DMA transfer: %d", ret);
return ret;
}
/* Clear status register */
(void)ssc->SSC_SR;
ssc->SSC_IER = SSC_IER_OVRUN;
ssc->SSC_CR = SSC_CR_RXEN;
return 0;
}
static int tx_stream_start(struct stream *stream, Ssc *const ssc,
const struct device *dev_dma)
{
size_t mem_block_size;
int ret;
ret = queue_get(&stream->mem_block_queue, &stream->mem_block,
&mem_block_size);
if (ret < 0) {
return ret;
}
k_sem_give(&stream->sem);
/* Workaround for a hardware bug: DMA engine will transfer first data
* item even if SSC_SR.TXEN (Transmit Enable) is not set. An extra write
* before enabling DMA engine sets hardware FSM in the correct state.
* This data item will not be output on I2S interface.
*/
ssc->SSC_THR = 0;
struct dma_config dma_cfg = {
.source_data_size = stream->word_size_bytes,
.dest_data_size = stream->word_size_bytes,
.block_count = 1,
.dma_slot = stream->dma_perid,
.channel_direction = MEMORY_TO_PERIPHERAL,
.source_burst_length = 1,
.dest_burst_length = 1,
.dma_callback = dma_tx_callback,
};
/* Assure cache coherency before DMA read operation */
DCACHE_CLEAN(stream->mem_block, mem_block_size);
ret = start_dma(dev_dma, stream->dma_channel, &dma_cfg,
stream->mem_block, (void *)&(ssc->SSC_THR),
mem_block_size);
if (ret < 0) {
LOG_ERR("Failed to start TX DMA transfer: %d", ret);
return ret;
}
/* Clear status register */
(void)ssc->SSC_SR;
ssc->SSC_IER = SSC_IER_TXEMPTY;
ssc->SSC_CR = SSC_CR_TXEN;
return 0;
}
static void rx_stream_disable(struct stream *stream, Ssc *const ssc,
const struct device *dev_dma)
{
ssc->SSC_CR = SSC_CR_RXDIS;
ssc->SSC_IDR = SSC_IDR_OVRUN;
dma_stop(dev_dma, stream->dma_channel);
if (stream->mem_block != NULL) {
k_mem_slab_free(stream->cfg.mem_slab, &stream->mem_block);
stream->mem_block = NULL;
}
}
static void tx_stream_disable(struct stream *stream, Ssc *const ssc,
const struct device *dev_dma)
{
ssc->SSC_CR = SSC_CR_TXDIS;
ssc->SSC_IDR = SSC_IDR_TXEMPTY;
dma_stop(dev_dma, stream->dma_channel);
if (stream->mem_block != NULL) {
k_mem_slab_free(stream->cfg.mem_slab, &stream->mem_block);
stream->mem_block = NULL;
}
}
static void rx_queue_drop(struct stream *stream)
{
size_t size;
void *mem_block;
while (queue_get(&stream->mem_block_queue, &mem_block, &size) == 0) {
k_mem_slab_free(stream->cfg.mem_slab, &mem_block);
}
k_sem_reset(&stream->sem);
}
static void tx_queue_drop(struct stream *stream)
{
size_t size;
void *mem_block;
unsigned int n = 0U;
while (queue_get(&stream->mem_block_queue, &mem_block, &size) == 0) {
k_mem_slab_free(stream->cfg.mem_slab, &mem_block);
n++;
}
for (; n > 0; n--) {
k_sem_give(&stream->sem);
}
}
static int i2s_sam_trigger(const struct device *dev, enum i2s_dir dir,
enum i2s_trigger_cmd cmd)
{
const struct i2s_sam_dev_cfg *const dev_cfg = dev->config;
struct i2s_sam_dev_data *const dev_data = dev->data;
Ssc *const ssc = dev_cfg->regs;
struct stream *stream;
unsigned int key;
int ret;
if (dir == I2S_DIR_RX) {
stream = &dev_data->rx;
} else if (dir == I2S_DIR_TX) {
stream = &dev_data->tx;
} else if (dir == I2S_DIR_BOTH) {
return -ENOSYS;
} else {
LOG_ERR("Either RX or TX direction must be selected");
return -EINVAL;
}
switch (cmd) {
case I2S_TRIGGER_START:
if (stream->state != I2S_STATE_READY) {
LOG_DBG("START trigger: invalid state");
return -EIO;
}
__ASSERT_NO_MSG(stream->mem_block == NULL);
ret = stream->stream_start(stream, ssc, dev_cfg->dev_dma);
if (ret < 0) {
LOG_DBG("START trigger failed %d", ret);
return ret;
}
stream->state = I2S_STATE_RUNNING;
stream->last_block = false;
break;
case I2S_TRIGGER_STOP:
key = irq_lock();
if (stream->state != I2S_STATE_RUNNING) {
irq_unlock(key);
LOG_DBG("STOP trigger: invalid state");
return -EIO;
}
stream->state = I2S_STATE_STOPPING;
irq_unlock(key);
stream->last_block = true;
break;
case I2S_TRIGGER_DRAIN:
key = irq_lock();
if (stream->state != I2S_STATE_RUNNING) {
irq_unlock(key);
LOG_DBG("DRAIN trigger: invalid state");
return -EIO;
}
stream->state = I2S_STATE_STOPPING;
irq_unlock(key);
break;
case I2S_TRIGGER_DROP:
if (stream->state == I2S_STATE_NOT_READY) {
LOG_DBG("DROP trigger: invalid state");
return -EIO;
}
stream->stream_disable(stream, ssc, dev_cfg->dev_dma);
stream->queue_drop(stream);
stream->state = I2S_STATE_READY;
break;
case I2S_TRIGGER_PREPARE:
if (stream->state != I2S_STATE_ERROR) {
LOG_DBG("PREPARE trigger: invalid state");
return -EIO;
}
stream->state = I2S_STATE_READY;
stream->queue_drop(stream);
break;
default:
LOG_ERR("Unsupported trigger command");
return -EINVAL;
}
return 0;
}
static int i2s_sam_read(const struct device *dev, void **mem_block,
size_t *size)
{
struct i2s_sam_dev_data *const dev_data = dev->data;
int ret;
if (dev_data->rx.state == I2S_STATE_NOT_READY) {
LOG_DBG("invalid state");
return -EIO;
}
if (dev_data->rx.state != I2S_STATE_ERROR) {
ret = k_sem_take(&dev_data->rx.sem,
SYS_TIMEOUT_MS(dev_data->rx.cfg.timeout));
if (ret < 0) {
return ret;
}
}
/* Get data from the beginning of RX queue */
ret = queue_get(&dev_data->rx.mem_block_queue, mem_block, size);
if (ret < 0) {
return -EIO;
}
return 0;
}
static int i2s_sam_write(const struct device *dev, void *mem_block,
size_t size)
{
struct i2s_sam_dev_data *const dev_data = dev->data;
int ret;
if (dev_data->tx.state != I2S_STATE_RUNNING &&
dev_data->tx.state != I2S_STATE_READY) {
LOG_DBG("invalid state");
return -EIO;
}
ret = k_sem_take(&dev_data->tx.sem,
SYS_TIMEOUT_MS(dev_data->tx.cfg.timeout));
if (ret < 0) {
return ret;
}
/* Add data to the end of the TX queue */
queue_put(&dev_data->tx.mem_block_queue, mem_block, size);
return 0;
}
static void i2s_sam_isr(const struct device *dev)
{
const struct i2s_sam_dev_cfg *const dev_cfg = dev->config;
struct i2s_sam_dev_data *const dev_data = dev->data;
Ssc *const ssc = dev_cfg->regs;
uint32_t isr_status;
/* Retrieve interrupt status */
isr_status = ssc->SSC_SR & ssc->SSC_IMR;
/* Check for RX buffer overrun */
if (isr_status & SSC_SR_OVRUN) {
dev_data->rx.state = I2S_STATE_ERROR;
/* Disable interrupt */
ssc->SSC_IDR = SSC_IDR_OVRUN;
LOG_DBG("RX buffer overrun error");
}
/* Check for TX buffer underrun */
if (isr_status & SSC_SR_TXEMPTY) {
dev_data->tx.state = I2S_STATE_ERROR;
/* Disable interrupt */
ssc->SSC_IDR = SSC_IDR_TXEMPTY;
LOG_DBG("TX buffer underrun error");
}
}
static int i2s_sam_initialize(const struct device *dev)
{
const struct i2s_sam_dev_cfg *const dev_cfg = dev->config;
struct i2s_sam_dev_data *const dev_data = dev->data;
Ssc *const ssc = dev_cfg->regs;
int ret;
/* Configure interrupts */
dev_cfg->irq_config();
/* Initialize semaphores */
k_sem_init(&dev_data->rx.sem, 0, CONFIG_I2S_SAM_SSC_RX_BLOCK_COUNT);
k_sem_init(&dev_data->tx.sem, CONFIG_I2S_SAM_SSC_TX_BLOCK_COUNT,
CONFIG_I2S_SAM_SSC_TX_BLOCK_COUNT);
if (!device_is_ready(dev_cfg->dev_dma)) {
LOG_ERR("%s device not ready", dev_cfg->dev_dma->name);
return -ENODEV;
}
/* Connect pins to the peripheral */
ret = pinctrl_apply_state(dev_cfg->pcfg, PINCTRL_STATE_DEFAULT);
if (ret < 0) {
return ret;
}
/* Enable module's clock */
soc_pmc_peripheral_enable(dev_cfg->periph_id);
/* Reset the module, disable receiver & transmitter */
ssc->SSC_CR = SSC_CR_RXDIS | SSC_CR_TXDIS | SSC_CR_SWRST;
/* Enable module's IRQ */
irq_enable(dev_cfg->irq_id);
LOG_INF("Device %s initialized", dev->name);
return 0;
}
static const struct i2s_driver_api i2s_sam_driver_api = {
.configure = i2s_sam_configure,
.config_get = i2s_sam_config_get,
.read = i2s_sam_read,
.write = i2s_sam_write,
.trigger = i2s_sam_trigger,
};
/* I2S0 */
static const struct device *get_dev_from_dma_channel(uint32_t dma_channel)
{
return &DEVICE_DT_NAME_GET(DT_DRV_INST(0));
}
static void i2s0_sam_irq_config(void)
{
IRQ_CONNECT(DT_INST_IRQN(0), DT_INST_IRQ(0, priority), i2s_sam_isr,
DEVICE_DT_INST_GET(0), 0);
}
PINCTRL_DT_INST_DEFINE(0);
static const struct i2s_sam_dev_cfg i2s0_sam_config = {
.dev_dma = DEVICE_DT_GET(DT_INST_DMAS_CTLR_BY_NAME(0, tx)),
.regs = (Ssc *)DT_INST_REG_ADDR(0),
.irq_config = i2s0_sam_irq_config,
.periph_id = DT_INST_PROP(0, peripheral_id),
.irq_id = DT_INST_IRQN(0),
.pcfg = PINCTRL_DT_INST_DEV_CONFIG_GET(0),
};
struct queue_item rx_0_ring_buf[CONFIG_I2S_SAM_SSC_RX_BLOCK_COUNT + 1];
struct queue_item tx_0_ring_buf[CONFIG_I2S_SAM_SSC_TX_BLOCK_COUNT + 1];
static struct i2s_sam_dev_data i2s0_sam_data = {
.rx = {
.dma_channel = DT_INST_DMAS_CELL_BY_NAME(0, rx, channel),
.dma_perid = DT_INST_DMAS_CELL_BY_NAME(0, rx, perid),
.mem_block_queue.buf = rx_0_ring_buf,
.mem_block_queue.len = ARRAY_SIZE(rx_0_ring_buf),
.stream_start = rx_stream_start,
.stream_disable = rx_stream_disable,
.queue_drop = rx_queue_drop,
.set_data_format = set_rx_data_format,
},
.tx = {
.dma_channel = DT_INST_DMAS_CELL_BY_NAME(0, tx, channel),
.dma_perid = DT_INST_DMAS_CELL_BY_NAME(0, tx, perid),
.mem_block_queue.buf = tx_0_ring_buf,
.mem_block_queue.len = ARRAY_SIZE(tx_0_ring_buf),
.stream_start = tx_stream_start,
.stream_disable = tx_stream_disable,
.queue_drop = tx_queue_drop,
.set_data_format = set_tx_data_format,
},
};
DEVICE_DT_INST_DEFINE(0, &i2s_sam_initialize, NULL,
&i2s0_sam_data, &i2s0_sam_config, POST_KERNEL,
CONFIG_I2S_INIT_PRIORITY, &i2s_sam_driver_api);