added esp32 spi daemon

9 files changed, 848 insertions, 0 deletions

diff --git a/recipes-bsp/esp32spid/esp32spid_0.1.bb b/recipes-bsp/esp32spid/esp32spid_0.1.bb
new file mode 100644
index 0000000..6a580a0
--- /dev/null
+++ b/recipes-bsp/esp32spid/esp32spid_0.1.bb
@@ -0,0 +1,23 @@
+DESCRIPTION = "esp32 spi daemon"
+SECTION = "base"
+LICENSE = "GPLv2"
+LIC_FILES_CHKSUM = 
+	file://${WORKDIR}/src/LICENSE;md5=b234ee4d69f5fce4486a80fdaf4a4263"
+PR = "r0"
+
+SRC_URI = " \
+	file://src/ \
+"
+
+do_compile () {
+	cd ${WORKDIR}/src
+	${MAKE}
+}
+
+do_install () {
+	install -d ${D}${bindir}
+	install -m 0755 ${WORKDIR}//src/esp32spid ${D}${bindir}/
+}
+
+DEPENDS = "libgpiod-dev"
+RDEPENDS_${PN} = "libgpiod"
\ No newline at end of file
diff --git a/recipes-bsp/esp32spid/src/LICENSE b/recipes-bsp/esp32spid/src/LICENSE
new file mode 100644
index 0000000..d159169
--- /dev/null
+++ b/recipes-bsp/esp32spid/src/LICENSE
@@ -0,0 +1,339 @@
+                    GNU GENERAL PUBLIC LICENSE
+                       Version 2, June 1991
+
+ Copyright (C) 1989, 1991 Free Software Foundation, Inc.,
+ 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ Everyone is permitted to copy and distribute verbatim copies
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+
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diff --git a/recipes-bsp/esp32spid/src/Makefile b/recipes-bsp/esp32spid/src/Makefile
new file mode 100644
index 0000000..fcecbd5
--- /dev/null
+++ b/recipes-bsp/esp32spid/src/Makefile
@@ -0,0 +1,15 @@
+#CFLAGS =
+LDFLAGS = -pthread -lgpiod
+TARGET = esp32spid
+obj = msgq.o spi.o tun.o
+
+all: $(TARGET)
+
+%.o: %.c %.h
+	$(CC) $(CFLAGS) -c $<
+
+$(TARGET): $(obj)
+	$(CC) $(obj) $(LDFLAGS) -o $@
+
+clean:
+	rm -f $(TARGET) *.o
diff --git a/recipes-bsp/esp32spid/src/msgq.c b/recipes-bsp/esp32spid/src/msgq.c
new file mode 100644
index 0000000..ff9f59e
--- /dev/null
+++ b/recipes-bsp/esp32spid/src/msgq.c
@@ -0,0 +1,42 @@
+#include <stdlib.h>
+#include <pthread.h>
+
+#include "msgq.h"
+
+#define IDX_MASK(IDX, SIZE)     ((IDX) & ((SIZE) - 1))
+
+int msgq_init(MSGQueue *msgq, unsigned char **array, uint16_t size) {
+    int rv;
+
+    msgq->idx_r = 0;
+    msgq->idx_w = 0;
+    msgq->size = size;
+    msgq->array = array;
+    rv = pthread_mutex_init(&msgq->mutex, NULL);
+    if (rv) {
+        return MSGQ_ERR;
+    }
+
+    rv = pthread_cond_init(&msgq->cond, NULL);
+    if (rv) {
+        pthread_mutex_destroy(&msgq->mutex);
+        return MSGQ_ERR;
+    }
+}
+
+int msgq_push(MSGQueue *msgq, unsigned char *buffer) {
+    if ((uint16_t)(msgq->idx_w - msgq->idx_r) == msgq->size) return MSGQ_ERR_FULL;
+
+    msgq->array[IDX_MASK(msgq->idx_w++, msgq->size)] = buffer;
+    return MSGQ_OK;
+}
+
+unsigned char *msgq_pop(MSGQueue *msgq) {
+    if (msgq->idx_r == msgq->idx_w) return NULL;
+
+    return msgq->array[IDX_MASK(msgq->idx_r++, msgq->size)];
+}
+
+uint16_t msgq_len(MSGQueue *msgq) {
+    return (uint16_t)(msgq->idx_w - msgq->idx_r);
+}
diff --git a/recipes-bsp/esp32spid/src/msgq.h b/recipes-bsp/esp32spid/src/msgq.h
new file mode 100644
index 0000000..665be32
--- /dev/null
+++ b/recipes-bsp/esp32spid/src/msgq.h
@@ -0,0 +1,19 @@
+#include <stdint.h>
+
+#define MSGQ_OK		0
+#define MSGQ_ERR	-1
+#define MSGQ_ERR_FULL	-10
+
+typedef struct MSGQueue {
+    uint16_t idx_r;
+    uint16_t idx_w;
+    uint16_t size;
+    unsigned char **array;
+    pthread_mutex_t mutex;
+    pthread_cond_t cond;
+} MSGQueue;
+
+int msgq_init(MSGQueue *msgq, unsigned char **array, uint16_t size);
+int msgq_push(MSGQueue *msgq, unsigned char *buffer);
+unsigned char *msgq_pop(MSGQueue *msgq);
+uint16_t msgq_len(MSGQueue *msgq);
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);
+}
diff --git a/recipes-bsp/esp32spid/src/spi.h b/recipes-bsp/esp32spid/src/spi.h
new file mode 100644
index 0000000..c1a4d94
--- /dev/null
+++ b/recipes-bsp/esp32spid/src/spi.h
@@ -0,0 +1,24 @@
+#include <stdint.h>
+
+#define SPI_GPIO_BANK       "gpiochip2"
+#define SPI_GPIO_CTS        3
+#define SPI_GPIO_RTS        4
+
+#define SPI_MTU             1500
+#define SPI_SIZE_BUF        (SPI_MTU + 8)
+#define SPI_SIZE_HDR        3
+
+#define SPI_SIZE_BUFQ       64
+#define SPI_SIZE_MSGQ       256
+
+#define SPI_MTYPE_TUN       1
+
+#define SPI_OK              0
+#define SPI_ERR	            -1
+#define SPI_ERR_OPEN        -10
+#define SPI_ERR_MSG         -11
+
+unsigned char *spi_alloc(void);
+void spi_free(unsigned char *buffer);
+int spi_xchg(unsigned char mtype, unsigned char *buffer, uint16_t len);
+int spi_init(char *fname);
\ No newline at end of file
diff --git a/recipes-bsp/esp32spid/src/tun.c b/recipes-bsp/esp32spid/src/tun.c
new file mode 100644
index 0000000..d75edc4
--- /dev/null
+++ b/recipes-bsp/esp32spid/src/tun.c
@@ -0,0 +1,94 @@
+#include <stdlib.h>
+#include <unistd.h>
+#include <string.h>
+#include <stdio.h>
+#include <fcntl.h>
+#include <sys/ioctl.h>
+
+#include <linux/if.h>
+#include <linux/if_tun.h>
+
+#include <pthread.h>
+
+#include "spi.h"
+#include "tun.h"
+
+static pthread_t read_thd;
+
+static int tun_fd;
+static char tun_name[IFNAMSIZ];
+
+static int tun_alloc(char *dev, int flags) {
+    struct ifreq ifr;
+    int fd, err;
+    char *clonedev = "/dev/net/tun";
+
+    /* Arguments taken by the function:
+     *
+     * char *dev: the name of an interface (or '\0'). MUST have enough
+     *   space to hold the interface name if '\0' is passed
+     * int flags: interface flags (eg, IFF_TUN etc.)
+     */
+
+    fd = open(clonedev, O_RDWR);
+    if (fd < 0) {
+        return fd;
+    }
+
+    memset(&ifr, 0, sizeof(ifr));
+    ifr.ifr_flags = flags;  /* IFF_TUN or IFF_TAP, plus maybe IFF_NO_PI */
+
+    if (*dev) {
+        /* if a device name was specified, put it in the structure; otherwise,
+         * the kernel will try to allocate the "next" device of the
+         * specified type */
+        strncpy(ifr.ifr_name, dev, IFNAMSIZ);
+    }
+
+    /* try to create the device */
+    err = ioctl(fd, TUNSETIFF, (void *) &ifr);
+    if (err < 0) {
+        close(fd);
+        return err;
+    }
+
+    /* if the operation was successful, write back the name of the
+     * interface to the variable "dev", so the caller can know
+     * it. Note that the caller MUST reserve space in *dev (see calling
+     * code below) */
+    strcpy(dev, ifr.ifr_name);
+
+    /* this is the special file descriptor that the caller will use to talk
+     * with the virtual interface */
+    return fd;
+}
+
+void *tun_read(void *arg) {
+    unsigned char *buffer;
+    int len;
+
+    while (1) {
+        buffer = spi_alloc();
+        if (buffer == NULL) continue;
+        len = read(tun_fd, buffer + SPI_SIZE_HDR, SPI_SIZE_BUF - SPI_SIZE_HDR);
+        if (len < 0) {
+            perror("tun read");
+            continue;
+        }
+        spi_xchg(SPI_MTYPE_TUN, buffer, len);
+    }
+}
+
+int tun_write(unsigned char *buffer, uint16_t len) {
+    return write(tun_fd, buffer, len);
+}
+
+int tun_init(void) {
+    int rv;
+
+    strcpy(tun_name, "tun0");
+    tun_fd = tun_alloc(tun_name, IFF_TUN | IFF_NO_PI);
+    if (tun_fd < 0) return TUN_ERR;
+
+    return TUN_OK;
+}
diff --git a/recipes-bsp/esp32spid/src/tun.h b/recipes-bsp/esp32spid/src/tun.h
new file mode 100644
index 0000000..bcfdac5
--- /dev/null
+++ b/recipes-bsp/esp32spid/src/tun.h
@@ -0,0 +1,8 @@
+#include <stdint.h>
+
+#define TUN_OK      0
+#define TUN_ERR     -1
+
+void *tun_read(void *arg);
+int tun_write(unsigned char *buffer, uint16_t len);
+int tun_init(void);
\ No newline at end of file