chris/Weather_ESP
1
0
Fork 0
Code Releases Activity
7ad1bce4a2
Weather_ESP/components/spidriver/spi_master_lobo.c

1138 lines
44 KiB
C
Raw Normal View History

Remove TFT_lib as a submodule and add as components again
2020-04-20 12:39:01 +02:00
// Copyright 2015-2016 Espressif Systems (Shanghai) PTE LTD
//
// 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.
/*
----------------------------------------
Non DMA version of the spi_master driver
----------------------------------------
------------------------------------------------------------------------------------
Based on esp-idf 'spi_master', modified by LoBo (https://github.com/loboris) 03/2017
------------------------------------------------------------------------------------
* Transfers data to SPI device in direct mode, not using DMA
* All configuration options (bus, device, transaction) are the same as in spi_master driver
* Transfers uses the semaphore (taken in select function & given in deselect function) to protect the transfer
* Number of the devices attached to the bus which uses hardware CS can be 3 ('NO_CS')
* Additional devices which uses software CS can be attached to the bus, up to 'NO_DEV'
* 'spi_bus_initialize' & 'spi_bus_remove' functions are removed, spi bus is initiated/removed in spi_lobo_bus_add_device/spi_lobo_bus_remove_device when needed
* 'spi_lobo_bus_add_device' function has added parameter 'bus_config' and automatically initializes spi bus device if not already initialized
* 'spi_lobo_bus_remove_device' automatically removes spi bus device if no other devices are attached to it.
* Devices can have individual bus_configs, so different mosi, miso, sck pins can be configured for each device
Reconfiguring the bus is done automaticaly in 'spi_lobo_device_select' function
* 'spi_lobo_device_select' & 'spi_lobo_device_deselect' functions handles devices configuration changes and software CS
* Some helper functions are added ('spi_lobo_get_speed', 'spi_lobo_set_speed', ...)
* All structures are available in header file for easy creation of user low level spi functions. See **tftfunc.c** source for examples.
* Transimt and receive lenghts are limited only by available memory
Main driver's function is 'spi_lobo_transfer_data()'
* TRANSMIT 8-bit data to spi device from 'trans->tx_buffer' or 'trans->tx_data' (trans->lenght/8 bytes)
* and RECEIVE data to 'trans->rx_buffer' or 'trans->rx_data' (trans->rx_length/8 bytes)
* Lengths must be 8-bit multiples!
* If trans->rx_buffer is NULL or trans->rx_length is 0, only transmits data
* If trans->tx_buffer is NULL or trans->length is 0, only receives data
* If the device is in duplex mode (LB_SPI_DEVICE_HALFDUPLEX flag NOT set), data are transmitted and received simultaneously.
* If the device is in half duplex mode (LB_SPI_DEVICE_HALFDUPLEX flag IS set), data are received after transmission
* 'address', 'command' and 'dummy bits' are transmitted before data phase IF set in device's configuration
* and IF 'trans->length' and 'trans->rx_length' are NOT both 0
* If configured, devices 'pre_cb' callback is called before and 'post_cb' after the transmission
* If device was not previously selected, it will be selected before transmission and deselected after transmission.
*/
/*
Replace this include with
#include "driver/spi_master_lobo.h"
if the driver is located in esp-isf/components
*/
#include "freertos/FreeRTOS.h"
#include <string.h>
#include "soc/spi_reg.h"
#include "soc/dport_reg.h"
#include "esp_log.h"
#include "freertos/semphr.h"
#include "driver/uart.h"
#include "driver/gpio.h"
#include "spi_master_lobo.h"
#include "driver/periph_ctrl.h"
static spi_lobo_host_t *spihost[3] = {NULL};
static const char *SPI_TAG = "spi_lobo_master";
#define SPI_CHECK(a, str, ret_val) \
if (!(a)) { \
ESP_LOGE(SPI_TAG,"%s(%d): %s", __FUNCTION__, __LINE__, str); \
return (ret_val); \
}
/*
Stores a bunch of per-spi-peripheral data.
*/
typedef struct {
const uint8_t spiclk_out; //GPIO mux output signals
const uint8_t spid_out;
const uint8_t spiq_out;
const uint8_t spiwp_out;
const uint8_t spihd_out;
const uint8_t spid_in; //GPIO mux input signals
const uint8_t spiq_in;
const uint8_t spiwp_in;
const uint8_t spihd_in;
const uint8_t spics_out[3]; // /CS GPIO output mux signals
const uint8_t spiclk_native; //IO pins of IO_MUX muxed signals
const uint8_t spid_native;
const uint8_t spiq_native;
const uint8_t spiwp_native;
const uint8_t spihd_native;
const uint8_t spics0_native;
const uint8_t irq; //irq source for interrupt mux
const uint8_t irq_dma; //dma irq source for interrupt mux
const periph_module_t module; //peripheral module, for enabling clock etc
spi_dev_t *hw; //Pointer to the hardware registers
} spi_signal_conn_t;
/*
Bunch of constants for every SPI peripheral: GPIO signals, irqs, hw addr of registers etc
*/
static const spi_signal_conn_t io_signal[3]={
{
.spiclk_out=SPICLK_OUT_IDX,
.spid_out=SPID_OUT_IDX,
.spiq_out=SPIQ_OUT_IDX,
.spiwp_out=SPIWP_OUT_IDX,
.spihd_out=SPIHD_OUT_IDX,
.spid_in=SPID_IN_IDX,
.spiq_in=SPIQ_IN_IDX,
.spiwp_in=SPIWP_IN_IDX,
.spihd_in=SPIHD_IN_IDX,
.spics_out={SPICS0_OUT_IDX, SPICS1_OUT_IDX, SPICS2_OUT_IDX},
.spiclk_native=6,
.spid_native=8,
.spiq_native=7,
.spiwp_native=10,
.spihd_native=9,
.spics0_native=11,
.irq=ETS_SPI1_INTR_SOURCE,
.irq_dma=ETS_SPI1_DMA_INTR_SOURCE,
.module=PERIPH_SPI_MODULE,
.hw=&SPI1
}, {
.spiclk_out=HSPICLK_OUT_IDX,
.spid_out=HSPID_OUT_IDX,
.spiq_out=HSPIQ_OUT_IDX,
.spiwp_out=HSPIWP_OUT_IDX,
.spihd_out=HSPIHD_OUT_IDX,
.spid_in=HSPID_IN_IDX,
.spiq_in=HSPIQ_IN_IDX,
.spiwp_in=HSPIWP_IN_IDX,
.spihd_in=HSPIHD_IN_IDX,
.spics_out={HSPICS0_OUT_IDX, HSPICS1_OUT_IDX, HSPICS2_OUT_IDX},
.spiclk_native=14,
.spid_native=13,
.spiq_native=12,
.spiwp_native=2,
.spihd_native=4,
.spics0_native=15,
.irq=ETS_SPI2_INTR_SOURCE,
.irq_dma=ETS_SPI2_DMA_INTR_SOURCE,
.module=PERIPH_HSPI_MODULE,
.hw=&SPI2
}, {
.spiclk_out=VSPICLK_OUT_IDX,
.spid_out=VSPID_OUT_IDX,
.spiq_out=VSPIQ_OUT_IDX,
.spiwp_out=VSPIWP_OUT_IDX,
.spihd_out=VSPIHD_OUT_IDX,
.spid_in=VSPID_IN_IDX,
.spiq_in=VSPIQ_IN_IDX,
.spiwp_in=VSPIWP_IN_IDX,
.spihd_in=VSPIHD_IN_IDX,
.spics_out={VSPICS0_OUT_IDX, VSPICS1_OUT_IDX, VSPICS2_OUT_IDX},
.spiclk_native=18,
.spid_native=23,
.spiq_native=19,
.spiwp_native=22,
.spihd_native=21,
.spics0_native=5,
.irq=ETS_SPI3_INTR_SOURCE,
.irq_dma=ETS_SPI3_DMA_INTR_SOURCE,
.module=PERIPH_VSPI_MODULE,
.hw=&SPI3
}
};
//======================================================================================================
#define DMA_CHANNEL_ENABLED(dma_chan) (BIT(dma_chan-1))
typedef void(*dmaworkaround_cb_t)(void *arg);
//Set up a list of dma descriptors. dmadesc is an array of descriptors. Data is the buffer to point to.
//--------------------------------------------------------------------------------------------
void spi_lobo_setup_dma_desc_links(lldesc_t *dmadesc, int len, const uint8_t *data, bool isrx)
{
int n = 0;
while (len) {
int dmachunklen = len;
if (dmachunklen > SPI_MAX_DMA_LEN) dmachunklen = SPI_MAX_DMA_LEN;
if (isrx) {
//Receive needs DMA length rounded to next 32-bit boundary
dmadesc[n].size = (dmachunklen + 3) & (~3);
dmadesc[n].length = (dmachunklen + 3) & (~3);
} else {
dmadesc[n].size = dmachunklen;
dmadesc[n].length = dmachunklen;
}
dmadesc[n].buf = (uint8_t *)data;
dmadesc[n].eof = 0;
dmadesc[n].sosf = 0;
dmadesc[n].owner = 1;
dmadesc[n].qe.stqe_next = &dmadesc[n + 1];
len -= dmachunklen;
data += dmachunklen;
n++;
}
dmadesc[n - 1].eof = 1; //Mark last DMA desc as end of stream.
dmadesc[n - 1].qe.stqe_next = NULL;
}
/*
Code for workaround for DMA issue in ESP32 v0/v1 silicon
*/
static volatile int dmaworkaround_channels_busy[2] = {0, 0};
static dmaworkaround_cb_t dmaworkaround_cb;
static void *dmaworkaround_cb_arg;
static portMUX_TYPE dmaworkaround_mux = portMUX_INITIALIZER_UNLOCKED;
static int dmaworkaround_waiting_for_chan = 0;
static bool spi_periph_claimed[3] = {true, false, false};
static uint8_t spi_dma_chan_enabled = 0;
static portMUX_TYPE spi_dma_spinlock = portMUX_INITIALIZER_UNLOCKED;
//--------------------------------------------------------------------------------------------
bool IRAM_ATTR spi_lobo_dmaworkaround_req_reset(int dmachan, dmaworkaround_cb_t cb, void *arg)
{
int otherchan = (dmachan == 1) ? 2 : 1;
bool ret;
portENTER_CRITICAL(&dmaworkaround_mux);
if (dmaworkaround_channels_busy[otherchan-1]) {
//Other channel is busy. Call back when it's done.
dmaworkaround_cb = cb;
dmaworkaround_cb_arg = arg;
dmaworkaround_waiting_for_chan = otherchan;
ret = false;
} else {
//Reset DMA
DPORT_SET_PERI_REG_MASK(DPORT_PERIP_RST_EN_REG, DPORT_SPI_DMA_RST);
DPORT_CLEAR_PERI_REG_MASK(DPORT_PERIP_RST_EN_REG, DPORT_SPI_DMA_RST);
ret = true;
}
portEXIT_CRITICAL(&dmaworkaround_mux);
return ret;
}
//-------------------------------------------------------
bool IRAM_ATTR spi_lobo_dmaworkaround_reset_in_progress()
{
return (dmaworkaround_waiting_for_chan != 0);
}
//-----------------------------------------------------
void IRAM_ATTR spi_lobo_dmaworkaround_idle(int dmachan)
{
portENTER_CRITICAL(&dmaworkaround_mux);
dmaworkaround_channels_busy[dmachan-1] = 0;
if (dmaworkaround_waiting_for_chan == dmachan) {
//Reset DMA
DPORT_SET_PERI_REG_MASK(DPORT_PERIP_RST_EN_REG, DPORT_SPI_DMA_RST);
DPORT_CLEAR_PERI_REG_MASK(DPORT_PERIP_RST_EN_REG, DPORT_SPI_DMA_RST);
dmaworkaround_waiting_for_chan = 0;
//Call callback
dmaworkaround_cb(dmaworkaround_cb_arg);
}
portEXIT_CRITICAL(&dmaworkaround_mux);
}
//----------------------------------------------------------------
void IRAM_ATTR spi_lobo_dmaworkaround_transfer_active(int dmachan)
{
portENTER_CRITICAL(&dmaworkaround_mux);
dmaworkaround_channels_busy[dmachan-1] = 1;
portEXIT_CRITICAL(&dmaworkaround_mux);
}
//Returns true if this peripheral is successfully claimed, false if otherwise.
//-----------------------------------------------------
bool spi_lobo_periph_claim(spi_lobo_host_device_t host)
{
bool ret = __sync_bool_compare_and_swap(&spi_periph_claimed[host], false, true);
if (ret) periph_module_enable(io_signal[host].module);
return ret;
}
//Returns true if this peripheral is successfully freed, false if otherwise.
//-----------------------------------------------
bool spi_lobo_periph_free(spi_lobo_host_device_t host)
{
bool ret = __sync_bool_compare_and_swap(&spi_periph_claimed[host], true, false);
if (ret) periph_module_disable(io_signal[host].module);
return ret;
}
//-----------------------------------------
bool spi_lobo_dma_chan_claim (int dma_chan)
{
bool ret = false;
assert( dma_chan == 1 || dma_chan == 2 );
portENTER_CRITICAL(&spi_dma_spinlock);
if ( !(spi_dma_chan_enabled & DMA_CHANNEL_ENABLED(dma_chan)) ) {
// get the channel only when it's not claimed yet.
spi_dma_chan_enabled |= DMA_CHANNEL_ENABLED(dma_chan);
ret = true;
}
periph_module_enable( PERIPH_SPI_DMA_MODULE );
portEXIT_CRITICAL(&spi_dma_spinlock);
return ret;
}
//---------------------------------------
bool spi_lobo_dma_chan_free(int dma_chan)
{
assert( dma_chan == 1 || dma_chan == 2 );
assert( spi_dma_chan_enabled & DMA_CHANNEL_ENABLED(dma_chan) );
portENTER_CRITICAL(&spi_dma_spinlock);
spi_dma_chan_enabled &= ~DMA_CHANNEL_ENABLED(dma_chan);
if ( spi_dma_chan_enabled == 0 ) {
//disable the DMA only when all the channels are freed.
periph_module_disable( PERIPH_SPI_DMA_MODULE );
}
portEXIT_CRITICAL(&spi_dma_spinlock);
return true;
}
//======================================================================================================
//----------------------------------------------------------------------------------------------------------------
static esp_err_t spi_lobo_bus_initialize(spi_lobo_host_device_t host, spi_lobo_bus_config_t *bus_config, int init)
{
bool native=true, spi_chan_claimed, dma_chan_claimed;
if (init > 0) {
/* ToDo: remove this when we have flash operations cooperating with this */
SPI_CHECK(host!=TFT_SPI_HOST, "SPI1 is not supported", ESP_ERR_NOT_SUPPORTED);
SPI_CHECK(host>=TFT_SPI_HOST && host<=TFT_VSPI_HOST, "invalid host", ESP_ERR_INVALID_ARG);
SPI_CHECK(spihost[host]==NULL, "host already in use", ESP_ERR_INVALID_STATE);
}
else {
SPI_CHECK(spihost[host]!=NULL, "host not in use", ESP_ERR_INVALID_STATE);
}
SPI_CHECK(bus_config->mosi_io_num<0 || GPIO_IS_VALID_OUTPUT_GPIO(bus_config->mosi_io_num), "spid pin invalid", ESP_ERR_INVALID_ARG);
SPI_CHECK(bus_config->sclk_io_num<0 || GPIO_IS_VALID_OUTPUT_GPIO(bus_config->sclk_io_num), "spiclk pin invalid", ESP_ERR_INVALID_ARG);
SPI_CHECK(bus_config->miso_io_num<0 || GPIO_IS_VALID_GPIO(bus_config->miso_io_num), "spiq pin invalid", ESP_ERR_INVALID_ARG);
SPI_CHECK(bus_config->quadwp_io_num<0 || GPIO_IS_VALID_OUTPUT_GPIO(bus_config->quadwp_io_num), "spiwp pin invalid", ESP_ERR_INVALID_ARG);
SPI_CHECK(bus_config->quadhd_io_num<0 || GPIO_IS_VALID_OUTPUT_GPIO(bus_config->quadhd_io_num), "spihd pin invalid", ESP_ERR_INVALID_ARG);
if (init > 0) {
spi_chan_claimed=spi_lobo_periph_claim(host);
SPI_CHECK(spi_chan_claimed, "host already in use", ESP_ERR_INVALID_STATE);
//spihost[host]=malloc(sizeof(spi_lobo_host_t));
spihost[host]=heap_caps_malloc(sizeof(spi_lobo_host_t), MALLOC_CAP_DMA);
if (spihost[host]==NULL) return ESP_ERR_NO_MEM;
memset(spihost[host], 0, sizeof(spi_lobo_host_t));
// Create semaphore
spihost[host]->spi_lobo_bus_mutex = xSemaphoreCreateMutex();
if (!spihost[host]->spi_lobo_bus_mutex) return ESP_ERR_NO_MEM;
}
spihost[host]->cur_device = -1;
memcpy(&spihost[host]->cur_bus_config, bus_config, sizeof(spi_lobo_bus_config_t));
//Check if the selected pins correspond to the native pins of the peripheral
if (bus_config->mosi_io_num >= 0 && bus_config->mosi_io_num!=io_signal[host].spid_native) native=false;
if (bus_config->miso_io_num >= 0 && bus_config->miso_io_num!=io_signal[host].spiq_native) native=false;
if (bus_config->sclk_io_num >= 0 && bus_config->sclk_io_num!=io_signal[host].spiclk_native) native=false;
if (bus_config->quadwp_io_num >= 0 && bus_config->quadwp_io_num!=io_signal[host].spiwp_native) native=false;
if (bus_config->quadhd_io_num >= 0 && bus_config->quadhd_io_num!=io_signal[host].spihd_native) native=false;
spihost[host]->no_gpio_matrix=native;
if (native) {
//All SPI native pin selections resolve to 1, so we put that here instead of trying to figure
//out which FUNC_GPIOx_xSPIxx to grab; they all are defined to 1 anyway.
if (bus_config->mosi_io_num > 0) PIN_FUNC_SELECT(GPIO_PIN_MUX_REG[bus_config->mosi_io_num], 1);
if (bus_config->miso_io_num > 0) PIN_FUNC_SELECT(GPIO_PIN_MUX_REG[bus_config->miso_io_num], 1);
if (bus_config->quadwp_io_num > 0) PIN_FUNC_SELECT(GPIO_PIN_MUX_REG[bus_config->quadwp_io_num], 1);
if (bus_config->quadhd_io_num > 0) PIN_FUNC_SELECT(GPIO_PIN_MUX_REG[bus_config->quadhd_io_num], 1);
if (bus_config->sclk_io_num > 0) PIN_FUNC_SELECT(GPIO_PIN_MUX_REG[bus_config->sclk_io_num], 1);
} else {
//Use GPIO
if (bus_config->mosi_io_num>0) {
PIN_FUNC_SELECT(GPIO_PIN_MUX_REG[bus_config->mosi_io_num], PIN_FUNC_GPIO);
gpio_set_direction(bus_config->mosi_io_num, GPIO_MODE_OUTPUT);
gpio_matrix_out(bus_config->mosi_io_num, io_signal[host].spid_out, false, false);
gpio_matrix_in(bus_config->mosi_io_num, io_signal[host].spid_in, false);
}
if (bus_config->miso_io_num>0) {
PIN_FUNC_SELECT(GPIO_PIN_MUX_REG[bus_config->miso_io_num], PIN_FUNC_GPIO);
gpio_set_direction(bus_config->miso_io_num, GPIO_MODE_INPUT);
gpio_matrix_out(bus_config->miso_io_num, io_signal[host].spiq_out, false, false);
gpio_matrix_in(bus_config->miso_io_num, io_signal[host].spiq_in, false);
}
if (bus_config->quadwp_io_num>0) {
PIN_FUNC_SELECT(GPIO_PIN_MUX_REG[bus_config->quadwp_io_num], PIN_FUNC_GPIO);
gpio_set_direction(bus_config->quadwp_io_num, GPIO_MODE_OUTPUT);
gpio_matrix_out(bus_config->quadwp_io_num, io_signal[host].spiwp_out, false, false);
gpio_matrix_in(bus_config->quadwp_io_num, io_signal[host].spiwp_in, false);
}
if (bus_config->quadhd_io_num>0) {
PIN_FUNC_SELECT(GPIO_PIN_MUX_REG[bus_config->quadhd_io_num], PIN_FUNC_GPIO);
gpio_set_direction(bus_config->quadhd_io_num, GPIO_MODE_OUTPUT);
gpio_matrix_out(bus_config->quadhd_io_num, io_signal[host].spihd_out, false, false);
gpio_matrix_in(bus_config->quadhd_io_num, io_signal[host].spihd_in, false);
}
if (bus_config->sclk_io_num>0) {
PIN_FUNC_SELECT(GPIO_PIN_MUX_REG[bus_config->sclk_io_num], PIN_FUNC_GPIO);
gpio_set_direction(bus_config->sclk_io_num, GPIO_MODE_OUTPUT);
gpio_matrix_out(bus_config->sclk_io_num, io_signal[host].spiclk_out, false, false);
}
}
periph_module_enable(io_signal[host].module);
spihost[host]->hw=io_signal[host].hw;
if (init > 0) {
dma_chan_claimed=spi_lobo_dma_chan_claim(init);
if ( !dma_chan_claimed ) {
spi_lobo_periph_free( host );
SPI_CHECK(dma_chan_claimed, "dma channel already in use", ESP_ERR_INVALID_STATE);
}
spihost[host]->dma_chan = init;
//See how many dma descriptors we need and allocate them
int dma_desc_ct=(bus_config->max_transfer_sz+SPI_MAX_DMA_LEN-1)/SPI_MAX_DMA_LEN;
if (dma_desc_ct==0) dma_desc_ct=1; //default to 4k when max is not given
spihost[host]->max_transfer_sz = dma_desc_ct*SPI_MAX_DMA_LEN;
spihost[host]->dmadesc_tx=heap_caps_malloc(sizeof(lldesc_t)*dma_desc_ct, MALLOC_CAP_DMA);
spihost[host]->dmadesc_rx=heap_caps_malloc(sizeof(lldesc_t)*dma_desc_ct, MALLOC_CAP_DMA);
if (!spihost[host]->dmadesc_tx || !spihost[host]->dmadesc_rx) goto nomem;
//Tell common code DMA workaround that our DMA channel is idle. If needed, the code will do a DMA reset.
spi_lobo_dmaworkaround_idle(spihost[host]->dma_chan);
// Reset DMA
spihost[host]->hw->dma_conf.val |= SPI_OUT_RST|SPI_IN_RST|SPI_AHBM_RST|SPI_AHBM_FIFO_RST;
spihost[host]->hw->dma_out_link.start=0;
spihost[host]->hw->dma_in_link.start=0;
spihost[host]->hw->dma_conf.val &= ~(SPI_OUT_RST|SPI_IN_RST|SPI_AHBM_RST|SPI_AHBM_FIFO_RST);
spihost[host]->hw->dma_conf.out_data_burst_en=1;
//Reset timing
spihost[host]->hw->ctrl2.val=0;
//Disable unneeded ints
spihost[host]->hw->slave.rd_buf_done=0;
spihost[host]->hw->slave.wr_buf_done=0;
spihost[host]->hw->slave.rd_sta_done=0;
spihost[host]->hw->slave.wr_sta_done=0;
spihost[host]->hw->slave.rd_buf_inten=0;
spihost[host]->hw->slave.wr_buf_inten=0;
spihost[host]->hw->slave.rd_sta_inten=0;
spihost[host]->hw->slave.wr_sta_inten=0;
//Force a transaction done interrupt. This interrupt won't fire yet because we initialized the SPI interrupt as
//disabled. This way, we can just enable the SPI interrupt and the interrupt handler will kick in, handling
//any transactions that are queued.
spihost[host]->hw->slave.trans_inten=1;
spihost[host]->hw->slave.trans_done=1;
//Select DMA channel.
DPORT_SET_PERI_REG_BITS(DPORT_SPI_DMA_CHAN_SEL_REG, 3, init, (host * 2));
}
return ESP_OK;
nomem:
if (spihost[host]) {
free(spihost[host]->dmadesc_tx);
free(spihost[host]->dmadesc_rx);
}
free(spihost[host]);
spi_lobo_periph_free(host);
return ESP_ERR_NO_MEM;
}
//---------------------------------------------------------------------------
static esp_err_t spi_lobo_bus_free(spi_lobo_host_device_t host, int dofree)
{
if ((host == TFT_SPI_HOST) || (host > TFT_VSPI_HOST)) return ESP_ERR_NOT_SUPPORTED; // invalid host
if (spihost[host] == NULL) return ESP_ERR_INVALID_STATE; // host not in use
if (dofree) {
for (int x=0; x<NO_DEV; x++) {
if (spihost[host]->device[x] != NULL) return ESP_ERR_INVALID_STATE; // not all devices freed
}
}
if ( spihost[host]->dma_chan > 0 ) {
spi_lobo_dma_chan_free ( spihost[host]->dma_chan );
}
spihost[host]->hw->slave.trans_inten=0;
spihost[host]->hw->slave.trans_done=0;
spi_lobo_periph_free(host);
if (dofree) {
vSemaphoreDelete(spihost[host]->spi_lobo_bus_mutex);
free(spihost[host]->dmadesc_tx);
free(spihost[host]->dmadesc_rx);
free(spihost[host]);
spihost[host] = NULL;
}
return ESP_OK;
}
//---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
esp_err_t spi_lobo_bus_add_device(spi_lobo_host_device_t host, spi_lobo_bus_config_t *bus_config, spi_lobo_device_interface_config_t *dev_config, spi_lobo_device_handle_t *handle)
{
if ((host == TFT_SPI_HOST) || (host > TFT_VSPI_HOST)) return ESP_ERR_NOT_SUPPORTED; // invalid host
if (spihost[host] == NULL) {
esp_err_t ret = spi_lobo_bus_initialize(host, bus_config, 1);
if (ret) return ret;
}
int freecs, maxdev;
int apbclk=APB_CLK_FREQ;
if (spihost[host] == NULL) return ESP_ERR_INVALID_STATE;
if (dev_config->spics_io_num >= 0) {
if (!GPIO_IS_VALID_OUTPUT_GPIO(dev_config->spics_io_num)) return ESP_ERR_INVALID_ARG;
if (dev_config->spics_ext_io_num > 0) dev_config->spics_ext_io_num = -1;
}
else {
//if ((dev_config->spics_ext_io_num <= 0) || (!GPIO_IS_VALID_OUTPUT_GPIO(dev_config->spics_ext_io_num))) return ESP_ERR_INVALID_ARG;
}
//ToDo: Check if some other device uses the same 'spics_ext_io_num'
if (dev_config->clock_speed_hz == 0) return ESP_ERR_INVALID_ARG;
if (dev_config->spics_io_num > 0) maxdev = NO_CS;
else maxdev = NO_DEV;
for (freecs=0; freecs<maxdev; freecs++) {
//See if this slot is free; reserve if it is by putting a dummy pointer in the slot. We use an atomic compare&swap to make this thread-safe.
if (__sync_bool_compare_and_swap(&spihost[host]->device[freecs], NULL, (spi_lobo_device_t *)1)) break;
}
if (freecs == maxdev) return ESP_ERR_NOT_FOUND;
// The hardware looks like it would support this, but actually setting cs_ena_pretrans when transferring in full
// duplex mode does absolutely nothing on the ESP32.
if ((dev_config->cs_ena_pretrans != 0) && (dev_config->flags & LB_SPI_DEVICE_HALFDUPLEX)) return ESP_ERR_INVALID_ARG;
// Speeds >=40MHz over GPIO matrix needs a dummy cycle, but these don't work for full-duplex connections.
if (((dev_config->flags & LB_SPI_DEVICE_HALFDUPLEX)==0) && (dev_config->clock_speed_hz > ((apbclk*2)/5)) && (!spihost[host]->no_gpio_matrix)) return ESP_ERR_INVALID_ARG;
//Allocate memory for device
spi_lobo_device_t *dev=malloc(sizeof(spi_lobo_device_t));
if (dev==NULL) return ESP_ERR_NO_MEM;
memset(dev, 0, sizeof(spi_lobo_device_t));
spihost[host]->device[freecs]=dev;
if (dev_config->duty_cycle_pos==0) dev_config->duty_cycle_pos=128;
dev->host=spihost[host];
dev->host_dev = host;
//We want to save a copy of the dev config in the dev struct.
memcpy(&dev->cfg, dev_config, sizeof(spi_lobo_device_interface_config_t));
//We want to save a copy of the bus config in the dev struct.
memcpy(&dev->bus_config, bus_config, sizeof(spi_lobo_bus_config_t));
//Set CS pin, CS options
if (dev_config->spics_io_num > 0) {
if (spihost[host]->no_gpio_matrix &&dev_config->spics_io_num == io_signal[host].spics0_native && freecs==0) {
//Again, the cs0s for all SPI peripherals map to pin mux source 1, so we use that instead of a define.
PIN_FUNC_SELECT(GPIO_PIN_MUX_REG[dev_config->spics_io_num], 1);
} else {
//Use GPIO matrix
PIN_FUNC_SELECT(GPIO_PIN_MUX_REG[dev_config->spics_io_num], PIN_FUNC_GPIO);
gpio_set_direction(dev_config->spics_io_num, GPIO_MODE_OUTPUT);
gpio_matrix_out(dev_config->spics_io_num, io_signal[host].spics_out[freecs], false, false);
}
}
else if (dev_config->spics_ext_io_num >= 0) {
gpio_set_direction(dev_config->spics_ext_io_num, GPIO_MODE_OUTPUT);
gpio_set_level(dev_config->spics_ext_io_num, 1);
}
if (dev_config->flags & LB_SPI_DEVICE_CLK_AS_CS) {
spihost[host]->hw->pin.master_ck_sel |= (1<<freecs);
} else {
spihost[host]->hw->pin.master_ck_sel &= (1<<freecs);
}
if (dev_config->flags & LB_SPI_DEVICE_POSITIVE_CS) {
spihost[host]->hw->pin.master_cs_pol |= (1<<freecs);
} else {
spihost[host]->hw->pin.master_cs_pol &= (1<<freecs);
}
*handle = dev;
return ESP_OK;
}
//-------------------------------------------------------------------
esp_err_t spi_lobo_bus_remove_device(spi_lobo_device_handle_t handle)
{
int x;
if (handle == NULL) return ESP_ERR_INVALID_ARG;
//Remove device from list of csses and free memory
for (x=0; x<NO_DEV; x++) {
if (handle->host->device[x] == handle) handle->host->device[x]=NULL;
}
// Check if all devices are removed from this host and free the bus if yes
for (x=0; x<NO_DEV; x++) {
if (spihost[handle->host_dev]->device[x] !=NULL) break;
}
if (x == NO_DEV) {
free(handle);
spi_lobo_bus_free(handle->host_dev, 1);
}
else free(handle);
return ESP_OK;
}
//-----------------------------------------------------------------
static int IRAM_ATTR spi_freq_for_pre_n(int fapb, int pre, int n) {
return (fapb / (pre * n));
}
/*
* Set the SPI clock to a certain frequency. Returns the effective frequency set, which may be slightly
* different from the requested frequency.
*/
//-----------------------------------------------------------------------------------
static int IRAM_ATTR spi_set_clock(spi_dev_t *hw, int fapb, int hz, int duty_cycle) {
int pre, n, h, l, eff_clk;
//In hw, n, h and l are 1-64, pre is 1-8K. Value written to register is one lower than used value.
if (hz>((fapb/4)*3)) {
//Using Fapb directly will give us the best result here.
hw->clock.clkcnt_l=0;
hw->clock.clkcnt_h=0;
hw->clock.clkcnt_n=0;
hw->clock.clkdiv_pre=0;
hw->clock.clk_equ_sysclk=1;
eff_clk=fapb;
} else {
//For best duty cycle resolution, we want n to be as close to 32 as possible, but
//we also need a pre/n combo that gets us as close as possible to the intended freq.
//To do this, we bruteforce n and calculate the best pre to go along with that.
//If there's a choice between pre/n combos that give the same result, use the one
//with the higher n.
int bestn=-1;
int bestpre=-1;
int besterr=0;
int errval;
for (n=1; n<=64; n++) {
//Effectively, this does pre=round((fapb/n)/hz).
pre=((fapb/n)+(hz/2))/hz;
if (pre<=0) pre=1;
if (pre>8192) pre=8192;
errval=abs(spi_freq_for_pre_n(fapb, pre, n)-hz);
if (bestn==-1 || errval<=besterr) {
besterr=errval;
bestn=n;
bestpre=pre;
}
}
n=bestn;
pre=bestpre;
l=n;
//This effectively does round((duty_cycle*n)/256)
h=(duty_cycle*n+127)/256;
if (h<=0) h=1;
hw->clock.clk_equ_sysclk=0;
hw->clock.clkcnt_n=n-1;
hw->clock.clkdiv_pre=pre-1;
hw->clock.clkcnt_h=h-1;
hw->clock.clkcnt_l=l-1;
eff_clk=spi_freq_for_pre_n(fapb, pre, n);
}
return eff_clk;
}
//------------------------------------------------------------------------------------
esp_err_t IRAM_ATTR spi_lobo_device_select(spi_lobo_device_handle_t handle, int force)
{
if (handle == NULL) return ESP_ERR_INVALID_ARG;
if ((handle->cfg.selected == 1) && (!force)) return ESP_OK; // already selected
int i;
spi_lobo_host_t *host=(spi_lobo_host_t*)handle->host;
// find device's host bus
for (i=0; i<NO_DEV; i++) {
if (host->device[i] == handle) break;
}
if (i == NO_DEV) return ESP_ERR_INVALID_ARG;
if (!(xSemaphoreTake(host->spi_lobo_bus_mutex, SPI_SEMAPHORE_WAIT))) return ESP_ERR_INVALID_STATE;
// Check if previously used device's bus device is the same
if (memcmp(&host->cur_bus_config, &handle->bus_config, sizeof(spi_lobo_bus_config_t)) != 0) {
// device has different bus configuration, we need to reconfigure the bus
esp_err_t err = spi_lobo_bus_free(1, 0);
if (err) {
xSemaphoreGive(host->spi_lobo_bus_mutex);
return err;
}
err = spi_lobo_bus_initialize(i, &handle->bus_config, -1);
if (err) {
xSemaphoreGive(host->spi_lobo_bus_mutex);
return err;
}
}
//Reconfigure according to device settings, but only if the device changed or forced.
if ((force) || (host->device[host->cur_device] != handle)) {
//Assumes a hardcoded 80MHz Fapb for now. ToDo: figure out something better once we have clock scaling working.
int apbclk=APB_CLK_FREQ;
//Speeds >=40MHz over GPIO matrix needs a dummy cycle, but these don't work for full-duplex connections.
if (((handle->cfg.flags & LB_SPI_DEVICE_HALFDUPLEX) == 0) && (handle->cfg.clock_speed_hz > ((apbclk*2)/5)) && (!host->no_gpio_matrix)) {
// set speed to 32 MHz
handle->cfg.clock_speed_hz = (apbclk*2)/5;
}
int effclk=spi_set_clock(host->hw, apbclk, handle->cfg.clock_speed_hz, handle->cfg.duty_cycle_pos);
//Configure bit order
host->hw->ctrl.rd_bit_order=(handle->cfg.flags & LB_SPI_DEVICE_RXBIT_LSBFIRST)?1:0;
host->hw->ctrl.wr_bit_order=(handle->cfg.flags & LB_SPI_DEVICE_TXBIT_LSBFIRST)?1:0;
//Configure polarity
//SPI iface needs to be configured for a delay in some cases.
int nodelay=0;
int extra_dummy=0;
if (host->no_gpio_matrix) {
if (effclk >= apbclk/2) {
nodelay=1;
}
} else {
if (effclk >= apbclk/2) {
nodelay=1;
extra_dummy=1; //Note: This only works on half-duplex connections. spi_lobo_bus_add_device checks for this.
} else if (effclk >= apbclk/4) {
nodelay=1;
}
}
if (handle->cfg.mode==0) {
host->hw->pin.ck_idle_edge=0;
host->hw->user.ck_out_edge=0;
host->hw->ctrl2.miso_delay_mode=nodelay?0:2;
} else if (handle->cfg.mode==1) {
host->hw->pin.ck_idle_edge=0;
host->hw->user.ck_out_edge=1;
host->hw->ctrl2.miso_delay_mode=nodelay?0:1;
} else if (handle->cfg.mode==2) {
host->hw->pin.ck_idle_edge=1;
host->hw->user.ck_out_edge=1;
host->hw->ctrl2.miso_delay_mode=nodelay?0:1;
} else if (handle->cfg.mode==3) {
host->hw->pin.ck_idle_edge=1;
host->hw->user.ck_out_edge=0;
host->hw->ctrl2.miso_delay_mode=nodelay?0:2;
}
//Configure bit sizes, load addr and command
host->hw->user.usr_dummy=(handle->cfg.dummy_bits+extra_dummy)?1:0;
host->hw->user.usr_addr=(handle->cfg.address_bits)?1:0;
host->hw->user.usr_command=(handle->cfg.command_bits)?1:0;
host->hw->user1.usr_addr_bitlen=handle->cfg.address_bits-1;
host->hw->user1.usr_dummy_cyclelen=handle->cfg.dummy_bits+extra_dummy-1;
host->hw->user2.usr_command_bitlen=handle->cfg.command_bits-1;
//Configure misc stuff
host->hw->user.doutdin=(handle->cfg.flags & LB_SPI_DEVICE_HALFDUPLEX)?0:1;
host->hw->user.sio=(handle->cfg.flags & LB_SPI_DEVICE_3WIRE)?1:0;
host->hw->ctrl2.setup_time=handle->cfg.cs_ena_pretrans-1;
host->hw->user.cs_setup=handle->cfg.cs_ena_pretrans?1:0;
host->hw->ctrl2.hold_time=handle->cfg.cs_ena_posttrans-1;
host->hw->user.cs_hold=(handle->cfg.cs_ena_posttrans)?1:0;
//Configure CS pin
host->hw->pin.cs0_dis=(i==0)?0:1;
host->hw->pin.cs1_dis=(i==1)?0:1;
host->hw->pin.cs2_dis=(i==2)?0:1;
host->cur_device = i;
}
if ((handle->cfg.spics_io_num < 0) && (handle->cfg.spics_ext_io_num > 0)) {
gpio_set_level(handle->cfg.spics_ext_io_num, 0);
}
handle->cfg.selected = 1;
return ESP_OK;
}
//---------------------------------------------------------------------------
esp_err_t IRAM_ATTR spi_lobo_device_deselect(spi_lobo_device_handle_t handle)
{
if (handle == NULL) return ESP_ERR_INVALID_ARG;
if (handle->cfg.selected == 0) return ESP_OK; // already deselected
int i;
spi_lobo_host_t *host=(spi_lobo_host_t*)handle->host;
for (i=0; i<NO_DEV; i++) {
if (host->device[i] == handle) break;
}
if (i == NO_DEV) return ESP_ERR_INVALID_ARG;
if (host->device[host->cur_device] == handle) {
if ((handle->cfg.spics_io_num < 0) && (handle->cfg.spics_ext_io_num > 0)) {
gpio_set_level(handle->cfg.spics_ext_io_num, 1);
}
}
handle->cfg.selected = 0;
xSemaphoreGive(host->spi_lobo_bus_mutex);
return ESP_OK;
}
//--------------------------------------------------------------------------------
esp_err_t IRAM_ATTR spi_lobo_device_TakeSemaphore(spi_lobo_device_handle_t handle)
{
if (!(xSemaphoreTake(handle->host->spi_lobo_bus_mutex, SPI_SEMAPHORE_WAIT))) return ESP_ERR_INVALID_STATE;
else return ESP_OK;
}
//---------------------------------------------------------------------------
void IRAM_ATTR spi_lobo_device_GiveSemaphore(spi_lobo_device_handle_t handle)
{
xSemaphoreTake(handle->host->spi_lobo_bus_mutex, portMAX_DELAY);
}
//----------------------------------------------------------
uint32_t spi_lobo_get_speed(spi_lobo_device_handle_t handle)
{
spi_lobo_host_t *host=(spi_lobo_host_t*)handle->host;
uint32_t speed = 0;
if (spi_lobo_device_select(handle, 0) == ESP_OK) {
if (host->hw->clock.clk_equ_sysclk == 1) speed = 80000000;
else speed = 80000000/(host->hw->clock.clkdiv_pre+1)/(host->hw->clock.clkcnt_n+1);
}
spi_lobo_device_deselect(handle);
return speed;
}
//--------------------------------------------------------------------------
uint32_t spi_lobo_set_speed(spi_lobo_device_handle_t handle, uint32_t speed)
{
spi_lobo_host_t *host=(spi_lobo_host_t*)handle->host;
uint32_t newspeed = 0;
if (spi_lobo_device_select(handle, 0) == ESP_OK) {
spi_lobo_device_deselect(handle);
handle->cfg.clock_speed_hz = speed;
if (spi_lobo_device_select(handle, 1) == ESP_OK) {
if (host->hw->clock.clk_equ_sysclk == 1) newspeed = 80000000;
else newspeed = 80000000/(host->hw->clock.clkdiv_pre+1)/(host->hw->clock.clkcnt_n+1);
}
}
spi_lobo_device_deselect(handle);
return newspeed;
}
//-------------------------------------------------------------
bool spi_lobo_uses_native_pins(spi_lobo_device_handle_t handle)
{
return handle->host->no_gpio_matrix;
}
//-------------------------------------------------------------------
void spi_lobo_get_native_pins(int host, int *sdi, int *sdo, int *sck)
{
*sdo = io_signal[host].spid_native;
*sdi = io_signal[host].spiq_native;
*sck = io_signal[host].spiclk_native;
}
/*
When using 'spi_lobo_transfer_data' function we can have several scenarios:
A: Send only (trans->rxlength = 0)
B: Receive only (trans->txlength = 0)
C: Send & receive (trans->txlength > 0 & trans->rxlength > 0)
D: No operation (trans->txlength = 0 & trans->rxlength = 0)
*/
//----------------------------------------------------------------------------------------------------------
esp_err_t IRAM_ATTR spi_lobo_transfer_data(spi_lobo_device_handle_t handle, spi_lobo_transaction_t *trans) {
if (!handle) return ESP_ERR_INVALID_ARG;
// *** For now we can only handle 8-bit bytes transmission
if (((trans->length % 8) != 0) || ((trans->rxlength % 8) != 0)) return ESP_ERR_INVALID_ARG;
spi_lobo_host_t *host=(spi_lobo_host_t*)handle->host;
esp_err_t ret;
uint8_t do_deselect = 0;
const uint8_t *txbuffer = NULL;
uint8_t *rxbuffer = NULL;
if (trans->flags & LB_SPI_TRANS_USE_TXDATA) {
// Send data from 'trans->tx_data'
txbuffer=(uint8_t*)&trans->tx_data[0];
} else {
// Send data from 'trans->tx_buffer'
txbuffer=(uint8_t*)trans->tx_buffer;
}
if (trans->flags & LB_SPI_TRANS_USE_RXDATA) {
// Receive data to 'trans->rx_data'
rxbuffer=(uint8_t*)&trans->rx_data[0];
} else {
// Receive data to 'trans->rx_buffer'
rxbuffer=(uint8_t*)trans->rx_buffer;
}
// ** Set transmit & receive length in bytes
uint32_t txlen = trans->length / 8;
uint32_t rxlen = trans->rxlength / 8;
if (txbuffer == NULL) txlen = 0;
if (rxbuffer == NULL) rxlen = 0;
if ((rxlen == 0) && (txlen == 0)) {
// ** NOTHING TO SEND or RECEIVE, return
return ESP_ERR_INVALID_ARG;
}
// If using 'trans->tx_data' and/or 'trans->rx_data', maximum 4 bytes can be sent/received
if ((txbuffer == &trans->tx_data[0]) && (txlen > 4)) return ESP_ERR_INVALID_ARG;
if ((rxbuffer == &trans->rx_data[0]) && (rxlen > 4)) return ESP_ERR_INVALID_ARG;
// --- Wait for SPI bus ready ---
while (host->hw->cmd.usr);
// ** If the device was not selected, select it
if (handle->cfg.selected == 0) {
ret = spi_lobo_device_select(handle, 0);
if (ret) return ret;
do_deselect = 1; // We will deselect the device after the operation !
}
// ** Call pre-transmission callback, if any
if (handle->cfg.pre_cb) handle->cfg.pre_cb(trans);
// Test if operating in full duplex mode
uint8_t duplex = 1;
if (handle->cfg.flags & LB_SPI_DEVICE_HALFDUPLEX) duplex = 0; // Half duplex mode !
uint32_t bits, rdbits;
uint32_t wd;
uint8_t bc, rdidx;
uint32_t rdcount = rxlen; // Total number of bytes to read
uint32_t count = 0; // number of bytes transmitted
uint32_t rd_read = 0; // Number of bytes read so far
host->hw->user.usr_mosi_highpart = 0; // use the whole spi buffer
// ** Check if address phase will be used
host->hw->user2.usr_command_value=trans->command;
if (handle->cfg.address_bits>32) {
host->hw->addr=trans->address >> 32;
host->hw->slv_wr_status=trans->address & 0xffffffff;
} else {
host->hw->addr=trans->address & 0xffffffff;
}
// Check if we have to transmit some data
if (txlen > 0) {
host->hw->user.usr_mosi = 1;
uint8_t idx;
bits = 0; // remaining bits to send
idx = 0; // index to spi hw data_buf (16 32-bit words, 64 bytes, 512 bits)
// ** Transmit 'txlen' bytes
while (count < txlen) {
wd = 0;
for (bc=0;bc<32;bc+=8) {
wd |= (uint32_t)txbuffer[count] << bc;
count++; // Increment sent data count
bits += 8; // Increment bits count
if (count == txlen) break; // If all transmit data pushed to hw spi buffer break from the loop
}
host->hw->data_buf[idx] = wd;
idx++;
if (idx == 16) {
// hw SPI buffer full (all 64 bytes filled, START THE TRANSSACTION
host->hw->mosi_dlen.usr_mosi_dbitlen=bits-1; // Set mosi dbitlen
if ((duplex) && (rdcount > 0)) {
// In full duplex mode we are receiving while sending !
host->hw->miso_dlen.usr_miso_dbitlen = bits-1; // Set miso dbitlen
host->hw->user.usr_miso = 1;
}
else {
host->hw->miso_dlen.usr_miso_dbitlen = 0; // In half duplex mode nothing will be received
host->hw->user.usr_miso = 0;
}
// ** Start the transaction ***
host->hw->cmd.usr=1;
// Wait the transaction to finish
while (host->hw->cmd.usr);
if ((duplex) && (rdcount > 0)) {
// *** in full duplex mode transfer received data to input buffer ***
rdidx = 0;
while (bits > 0) {
wd = host->hw->data_buf[rdidx];
rdidx++;
for (bc=0;bc<32;bc+=8) { // get max 4 bytes
rxbuffer[rd_read++] = (uint8_t)((wd >> bc) & 0xFF);
rdcount--;
bits -= 8;
if (rdcount == 0) {
bits = 0;
break; // Finished reading data
}
}
}
}
bits = 0; // nothing in hw spi buffer yet
idx = 0; // start from the beginning of the hw spi buffer
}
}
// *** All transmit data are sent or pushed to hw spi buffer
// bits > 0 IF THERE ARE SOME DATA STILL WAITING IN THE HW SPI TRANSMIT BUFFER
if (bits > 0) {
// ** WE HAVE SOME DATA IN THE HW SPI TRANSMIT BUFFER
host->hw->mosi_dlen.usr_mosi_dbitlen = bits-1; // Set mosi dbitlen
if ((duplex) && (rdcount > 0)) {
// In full duplex mode we are receiving while sending !
host->hw->miso_dlen.usr_miso_dbitlen = bits-1; // Set miso dbitlen
host->hw->user.usr_miso = 1;
}
else {
host->hw->miso_dlen.usr_miso_dbitlen = 0; // In half duplex mode nothing will be received
host->hw->user.usr_miso = 0;
}
// ** Start the transaction ***
host->hw->cmd.usr=1;
// Wait the transaction to finish
while (host->hw->cmd.usr);
if ((duplex) && (rdcount > 0)) {
// *** in full duplex mode transfer received data to input buffer ***
rdidx = 0;
while (bits > 0) {
wd = host->hw->data_buf[rdidx];
rdidx++;
for (bc=0;bc<32;bc+=8) { // get max 4 bytes
rxbuffer[rd_read++] = (uint8_t)((wd >> bc) & 0xFF);
rdcount--;
bits -= 8;
if (bits == 0) break;
if (rdcount == 0) {
bits = 0;
break; // Finished reading data
}
}
}
}
}
//if (duplex) rdcount = 0; // In duplex mode receive only as many bytes as was transmitted
}
// ------------------------------------------------------------------------
// *** If rdcount = 0 we have nothing to receive and we exit the function
// This is true if no data receive was requested,
// or all the data was received in Full duplex mode during the transmission
// ------------------------------------------------------------------------
if (rdcount > 0) {
// ----------------------------------------------------------------------------------------------------------------
// *** rdcount > 0, we have to receive some data
// This is true if we operate in Half duplex mode when receiving after transmission is done,
// or not all data was received in Full duplex mode during the transmission (trans->rxlength > trans->txlength)
// ----------------------------------------------------------------------------------------------------------------
host->hw->user.usr_mosi = 0; // do not send
host->hw->user.usr_miso = 1; // do receive
while (rdcount > 0) {
if (rdcount <= 64) rdbits = rdcount * 8;
else rdbits = 64 * 8;
// Load receive buffer
host->hw->mosi_dlen.usr_mosi_dbitlen=0;
host->hw->miso_dlen.usr_miso_dbitlen=rdbits-1;
// ** Start the transaction ***
host->hw->cmd.usr=1;
// Wait the transaction to finish
while (host->hw->cmd.usr);
// *** transfer received data to input buffer ***
rdidx = 0;
while (rdbits > 0) {
wd = host->hw->data_buf[rdidx];
rdidx++;
for (bc=0;bc<32;bc+=8) {
rxbuffer[rd_read++] = (uint8_t)((wd >> bc) & 0xFF);
rdcount--;
rdbits -= 8;
if (rdcount == 0) {
rdbits = 0;
break;
}
}
}
}
}
// ** Call post-transmission callback, if any
if (handle->cfg.post_cb) handle->cfg.post_cb(trans);
if (do_deselect) {
// Spi device was selected in this function, we have to deselect it now
ret = spi_lobo_device_deselect(handle);
if (ret) return ret;
}
return ESP_OK;
}
Copy Permalink