From 6c4998209307cd84982bf056fafa3a3135667bb2 Mon Sep 17 00:00:00 2001
From: Uros Majstorovic <majstor@majstor.org>
Date: Fri, 27 Aug 2021 02:01:29 +0200
Subject: added esp32 spi daemon

---
 recipes-bsp/esp32spid/src/spi.c | 284 ++++++++++++++++++++++++++++++++++++++++
 1 file changed, 284 insertions(+)
 create mode 100644 recipes-bsp/esp32spid/src/spi.c

(limited to 'recipes-bsp/esp32spid/src/spi.c')

diff --git a/recipes-bsp/esp32spid/src/spi.c b/recipes-bsp/esp32spid/src/spi.c
new file mode 100644
index 0000000..5bd0718
--- /dev/null
+++ b/recipes-bsp/esp32spid/src/spi.c
@@ -0,0 +1,284 @@
+#include <stdlib.h>
+#include <unistd.h>
+#include <string.h>
+#include <stdio.h>
+#include <fcntl.h>
+#include <sys/ioctl.h>
+
+#include <linux/spi/spidev.h>
+
+#include <gpiod.h>
+#include <pthread.h>
+
+#include "msgq.h"
+#include "tun.h"
+#include "spi.h"
+
+static pthread_t rtscts_thd;
+static pthread_t worker_thd;
+static pthread_t handler_thd;
+static pthread_mutex_t mutex;
+
+struct gpiod_line *gpio_rts, *gpio_cts;
+static struct gpiod_line_bulk gpio_rtscts;
+
+static MSGQueue spi_bufq;
+static unsigned char *spi_bufq_array[SPI_SIZE_BUFQ];
+
+static MSGQueue spi_msgq_in;
+static unsigned char *spi_msgq_in_array[SPI_SIZE_MSGQ];
+
+static MSGQueue spi_msgq_out;
+static unsigned char *spi_msgq_out_array[SPI_SIZE_MSGQ];
+
+static uint32_t spi_speed = 5000000;
+static int spi_fd;
+
+static int _spi_xchg(unsigned char *buffer) {
+	int rv;
+    uint16_t len_tx;
+    uint16_t len_rx;
+	struct spi_ioc_transfer	tr;
+
+	memset(&tr, 0, sizeof(tr));
+	tr.tx_buf = (unsigned long)buffer;
+	tr.rx_buf = (unsigned long)buffer;
+	tr.speed_hz = spi_speed,
+
+    len_tx  = (uint16_t)buffer[1] << 8;
+    len_tx |= (uint16_t)buffer[2] & 0xFF;
+    if (len_tx > SPI_MTU) return SPI_ERR;
+
+    len_tx += SPI_SIZE_HDR;
+    // esp32 dma workaraund
+    if (len_tx < 8) {
+        len_tx = 8;
+    } else if (len_tx % 4 != 0) {
+        len_tx = (len_tx / 4 + 1) * 4;
+    }
+
+	tr.len = len_tx;
+
+    pthread_mutex_lock(&mutex);
+	rv = ioctl(spi_fd, SPI_IOC_MESSAGE(1), &tr);
+	if (rv < 0) return SPI_ERR_MSG;
+
+    len_rx  = (uint16_t)buffer[1] << 8;
+    len_rx |= (uint16_t)buffer[2] & 0xFF;
+    if (len_rx > SPI_MTU) return SPI_ERR;
+
+    len_rx += SPI_SIZE_HDR;
+    if (len_rx > len_tx) {
+        tr.tx_buf = (unsigned long)NULL;
+        tr.rx_buf = (unsigned long)(buffer + len_tx);
+
+        len_tx = len_rx - len_tx;
+        // esp32 dma workaraund
+        if (len_tx < 8) {
+            len_tx = 8;
+        } else if (len_tx % 4 != 0) {
+            len_tx = (len_tx / 4 + 1) * 4;
+        }
+
+    	tr.len = len_tx;
+
+        pthread_mutex_lock(&mutex);
+    	rv = ioctl(spi_fd, SPI_IOC_MESSAGE(1), &tr);
+    	if (rv < 0) return SPI_ERR_MSG;
+    }
+
+    return SPI_OK;
+}
+
+static void *spi_rtscts_handler(void *arg) {
+    MSGQueue *msgq_out = &spi_msgq_out;
+    int i, rv;
+    struct gpiod_line_bulk evt_lines;
+    struct gpiod_line_event event;
+
+    while (1) {
+        rv = gpiod_line_event_wait_bulk(&gpio_rtscts, NULL, &evt_lines);
+        if (rv < 0) continue;
+
+        for (i=0; i<gpiod_line_bulk_num_lines(&evt_lines); i++) {
+            struct gpiod_line *line;
+
+            line = gpiod_line_bulk_get_line(&evt_lines, i);
+            rv = gpiod_line_event_read(line, &event);
+            if (rv || (event.event_type != GPIOD_LINE_EVENT_RISING_EDGE)) continue;
+
+            switch (gpiod_line_offset(line)) {
+                case SPI_GPIO_RTS:
+                    pthread_mutex_lock(&msgq_out->mutex);
+                    pthread_cond_signal(&msgq_out->cond);
+                    pthread_mutex_unlock(&msgq_out->mutex);
+                    break;
+                case SPI_GPIO_CTS:
+                    pthread_mutex_unlock(&mutex);
+                    break;
+            }
+        }
+    }
+    return NULL;
+}
+
+static void *spi_worker(void *arg) {
+    MSGQueue *bufq = &spi_bufq;
+    MSGQueue *msgq_in = &spi_msgq_in;
+    MSGQueue *msgq_out = &spi_msgq_out;
+    int rv;
+    unsigned char *buffer;
+
+    while (1) {
+        pthread_mutex_lock(&msgq_out->mutex);
+        buffer = msgq_pop(msgq_out);
+        if ((buffer == NULL) && (gpiod_line_get_value(gpio_rts) == 1)) {
+            pthread_mutex_lock(&bufq->mutex);
+            buffer = msgq_pop(bufq);
+            pthread_mutex_unlock(&bufq->mutex);
+        }
+        if (buffer == NULL) {
+            pthread_cond_wait(&msgq_out->cond, &msgq_out->mutex);
+            buffer = msgq_pop(msgq_out);
+        }
+        pthread_mutex_unlock(&msgq_out->mutex);
+        if (buffer) {
+            rv = _spi_xchg(buffer);
+            if (rv || (buffer[0] == 0)) {
+                buffer[1] = 0;
+                buffer[2] = 0;
+                pthread_mutex_lock(&bufq->mutex);
+                rv = msgq_push(bufq, buffer);
+                pthread_mutex_unlock(&bufq->mutex);
+            } else {
+                pthread_mutex_lock(&msgq_in->mutex);
+                rv = msgq_push(msgq_in, buffer);
+                pthread_cond_signal(&msgq_in->cond);
+                pthread_mutex_unlock(&msgq_in->mutex);
+            }
+        }
+    }
+    return NULL;
+}
+
+static void *spi_handler(void *arg) {
+    MSGQueue *bufq = &spi_bufq;
+    MSGQueue *msgq_in = &spi_msgq_in;
+    unsigned char *buffer;
+    unsigned char mtype;
+    uint16_t len;
+    int rv;
+
+    while (1) {
+        pthread_mutex_lock(&msgq_in->mutex);
+        buffer = msgq_pop(msgq_in);
+        if (buffer == NULL) {
+            pthread_cond_wait(&msgq_in->cond, &msgq_in->mutex);
+            buffer = msgq_pop(msgq_in);
+        }
+        pthread_mutex_unlock(&msgq_in->mutex);
+        if (buffer) {
+            mtype = buffer[0];
+            len  = (uint16_t)buffer[1] << 8;
+            len |= (uint16_t)buffer[2] & 0xFF;
+
+            switch (mtype) {
+                case SPI_MTYPE_TUN:
+                    tun_write(buffer + SPI_SIZE_HDR, len);
+                    break;
+            }
+            buffer[0] = 0;
+            buffer[1] = 0;
+            buffer[2] = 0;
+            pthread_mutex_lock(&bufq->mutex);
+            rv = msgq_push(bufq, buffer);
+            pthread_mutex_unlock(&bufq->mutex);
+        }
+    }
+}
+
+unsigned char *spi_alloc(void) {
+    MSGQueue *bufq = &spi_bufq;
+    unsigned char *ret;
+
+    pthread_mutex_lock(&bufq->mutex);
+    ret = msgq_pop(bufq);
+    pthread_mutex_unlock(&bufq->mutex);
+
+    return ret;
+}
+
+void spi_free(unsigned char *buffer) {
+    MSGQueue *bufq = &spi_bufq;
+
+    buffer[0] = 0;
+    buffer[1] = 0;
+    buffer[2] = 0;
+    pthread_mutex_lock(&bufq->mutex);
+    msgq_push(bufq, buffer);
+    pthread_mutex_unlock(&bufq->mutex);
+}
+
+int spi_xchg(unsigned char mtype, unsigned char *buffer, uint16_t len) {
+	int rv;
+    MSGQueue *msgq_out = &spi_msgq_out;
+
+    buffer[0] = mtype;
+    buffer[1] = len >> 8;
+    buffer[2] = len & 0xFF;
+
+    pthread_mutex_lock(&msgq_out->mutex);
+    rv = msgq_push(msgq_out, buffer);
+    pthread_cond_signal(&msgq_out->cond);
+    pthread_mutex_unlock(&msgq_out->mutex);
+
+    return rv;
+}
+
+int spi_init(char *fname) {
+    int rv, i;
+    struct gpiod_chip *gpio_chip;
+
+	spi_fd = open(fname, O_RDWR);
+	if (spi_fd < 0) return SPI_ERR_OPEN;
+
+	rv = ioctl(spi_fd, SPI_IOC_WR_MAX_SPEED_HZ, &spi_speed);
+	if (rv == -1) return SPI_ERR;
+
+    gpio_chip = gpiod_chip_open_by_name(SPI_GPIO_BANK);
+    if (gpio_chip == NULL) return SPI_ERR;
+
+    gpio_rts = gpiod_chip_get_line(gpio_chip, SPI_GPIO_RTS);
+    gpio_cts = gpiod_chip_get_line(gpio_chip, SPI_GPIO_CTS);
+    if ((gpio_rts == NULL) || (gpio_cts == NULL)) return SPI_ERR;
+
+    gpiod_line_bulk_init(&gpio_rtscts);
+    gpiod_line_bulk_add(&gpio_rtscts, gpio_rts);
+    gpiod_line_bulk_add(&gpio_rtscts, gpio_cts);
+    rv = gpiod_line_request_bulk_rising_edge_events(&gpio_rtscts, "rtscts");
+    if (rv) return SPI_ERR;
+
+    msgq_init(&spi_bufq, spi_bufq_array, SPI_SIZE_BUFQ);
+    msgq_init(&spi_msgq_in, spi_msgq_in_array, SPI_SIZE_MSGQ);
+    msgq_init(&spi_msgq_out, spi_msgq_out_array, SPI_SIZE_MSGQ);
+    for (i=0; i<SPI_SIZE_BUFQ; i++) {
+        msgq_push(&spi_bufq, malloc(SPI_SIZE_BUF));
+    }
+
+    rv = pthread_mutex_init(&mutex, NULL);
+    rv = pthread_create(&rtscts_thd, NULL, spi_rtscts_handler, NULL);
+    rv = pthread_create(&worker_thd, NULL, spi_worker, NULL);
+    rv = pthread_create(&handler_thd, NULL, spi_handler, NULL);
+
+    return SPI_OK;
+}
+
+int main(int argc, char *argv[]) {
+    int rv;
+
+    rv = spi_init("/dev/spidev0.0");
+    if (rv) printf("SPI INIT ERR\n");
+    rv = tun_init();
+    if (rv) printf("TUN INIT ERR\n");
+    tun_read(NULL);
+}
-- 
cgit v1.2.3