diff options
Diffstat (limited to 'bcm4751_gpsd.c')
| -rw-r--r-- | bcm4751_gpsd.c | 294 |
1 files changed, 294 insertions, 0 deletions
diff --git a/bcm4751_gpsd.c b/bcm4751_gpsd.c new file mode 100644 index 0000000..5072751 --- /dev/null +++ b/bcm4751_gpsd.c @@ -0,0 +1,294 @@ +/** + * This file is part of BCM4751 gpsd + * + * Copyright (C) 2011 Paul Kocialkowski <contact@oaulk.fr> + * + * BCM4751 gpsd is free software: you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation, either version 3 of the License, or + * (at your option) any later version. + * + * BCM4751 gpsd is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with BCM4751 gpsd. If not, see <http://www.gnu.org/licenses/>. + */ + +#include <stdio.h> +#include <stdlib.h> +#include <stdint.h> +#include <unistd.h> +#include <termios.h> +#include <errno.h> + +#include <sys/types.h> +#include <sys/stat.h> +#include <fcntl.h> + +#include "meif.h" + +/* + * Utils + */ + +void hex_dump(void *data, int size) +{ + /* dumps size bytes of *data to stdout. Looks like: + * [0000] 75 6E 6B 6E 6F 77 6E 20 + * 30 FF 00 00 00 00 39 00 unknown 0.....9. + * (in a single line of course) + */ + + unsigned char *p = data; + unsigned char c; + int n; + char bytestr[4] = {0}; + char addrstr[10] = {0}; + char hexstr[ 16*3 + 5] = {0}; + char charstr[16*1 + 5] = {0}; + for(n=1;n<=size;n++) { + if (n%16 == 1) { + /* store address for this line */ + snprintf(addrstr, sizeof(addrstr), "%.4x", + ((unsigned int)p-(unsigned int)data) ); + } + + c = *p; + if (isalnum(c) == 0) { + c = '.'; + } + + /* store hex str (for left side) */ + snprintf(bytestr, sizeof(bytestr), "%02X ", *p); + strncat(hexstr, bytestr, sizeof(hexstr)-strlen(hexstr)-1); + + /* store char str (for right side) */ + snprintf(bytestr, sizeof(bytestr), "%c", c); + strncat(charstr, bytestr, sizeof(charstr)-strlen(charstr)-1); + + if(n%16 == 0) { + /* line completed */ + printf("[%4.4s] %-50.50s %s\n", addrstr, hexstr, charstr); + hexstr[0] = 0; + charstr[0] = 0; + } else if(n%8 == 0) { + /* half line: add whitespaces */ + strncat(hexstr, " ", sizeof(hexstr)-strlen(hexstr)-1); + strncat(charstr, " ", sizeof(charstr)-strlen(charstr)-1); + } + p++; /* next byte */ + } + + if (strlen(hexstr) > 0) { + /* print rest of buffer if not empty */ + printf("[%4.4s] %-50.50s %s\n", addrstr, hexstr, charstr); + } +} + +/* + * SEC + */ + +int sec_gps_power(int power) +{ + char gpio_power_path[] = "/sys/class/sec/gps/GPS_PWR_EN/value"; + char gpio_on_value[] = "1\n"; + char gpio_off_value[] = "0\n"; + int fd = -1; + int rc; + + fd = open(gpio_power_path, O_RDWR); + if(fd < 0) + return -1; + + if(power) { + rc = write(fd, gpio_on_value, strlen(gpio_on_value)); + } else { + rc = write(fd, gpio_off_value, strlen(gpio_off_value)); + } + + if(rc <= 0) { + close(fd); + return -1; + } + + close(fd); + + usleep(250000); + + return 0; +} + +int sec_gps_reset(int value) +{ + char gpio_reset_path[] = "/sys/class/sec/gps/GPS_nRST/value"; + char gpio_on_value[] = "1\n"; + char gpio_off_value[] = "0\n"; + int fd = -1; + int rc; + + fd = open(gpio_reset_path, O_RDWR); + if(fd < 0) + return -1; + + if(value) { + rc = write(fd, gpio_on_value, strlen(gpio_on_value)); + } else { + rc = write(fd, gpio_off_value, strlen(gpio_off_value)); + } + + if(rc <= 0) { + close(fd); + return -1; + } + + close(fd); + + usleep(250000); + + return 0; +} + +/* + * BCM4751 + */ + +int bcm4751_serial_open(void) +{ + struct termios termios; + int fd = -1; + + // TODO: add more checks + + fd = open("/dev/s3c2410_serial1", O_RDWR|O_NOCTTY|O_NONBLOCK); + if(fd < 0) + return -1; + + tcgetattr(fd, &termios); + + // Flush + ioctl(fd, TCFLSH, 0x2); + + cfmakeraw(&termios); + cfsetispeed(&termios, B115200); + cfsetospeed(&termios, B115200); + + // This is the magic to contact the chip + termios.c_cflag = 0x800018b2; + + tcsetattr(fd, TCSANOW, &termios); + + // Flush + ioctl(fd, TCFLSH, 0x2); + + return fd; +} + +int bcm4751_serial_read(int fd, void *data, int length, struct timeval *timeout) +{ + fd_set fds; + int rc = -1; + + FD_ZERO(&fds); + FD_SET(fd, &fds); + + rc = select(fd + 1, &fds, NULL, NULL, timeout); + if(rc > 0 && length > 0) { + rc = read(fd, data, length); + } + + return rc; +} + +int bcm4751_serial_write(int fd, void *data, int length, struct timeval *timeout) +{ + fd_set fds; + int rc = -1; + + FD_ZERO(&fds); + FD_SET(fd, &fds); + + rc = select(fd + 1, NULL, &fds, NULL, timeout); + if(rc > 0) { + rc = write(fd, data, length); + } + + return rc; +} + +int bcm4751_autobaud(int fd) +{ + struct timeval timeout; + uint8_t autobaud[20] = { 0x80 }; + int ready = 0; + int rc = -1; + + // TODO: limit the number of attempts + + timeout.tv_sec = 1; + timeout.tv_usec = 0; + + while(!ready) { + bcm4751_serial_write(fd, autobaud, sizeof(autobaud), NULL); + + rc = bcm4751_serial_read(fd, NULL, 0, &timeout); + if(rc > 0) + ready = 1; + } + + return 0; +} + +void bcm4751_read_dump(int fd) +{ + void *data = NULL; + int length = 0x100; + int rc = -1; + + data = malloc(length); + + while(1) { + rc = bcm4751_serial_read(fd, data, length, NULL); + if(rc > 0) { + printf("Read %d bytes:\n", rc); + hex_dump(data, rc); + } else { + free(data); + return; + } + } +} + +int main(void) +{ + int fd = -1; + int rc = -1; + + printf("Turning the GPS on...\n"); + rc = sec_gps_power(1); + if(rc < 0) { + printf("Failed to turn the GPS on!\n"); + return 1; + } + + printf("Opening the GPS serial...\n"); + fd = bcm4751_serial_open(); + if(fd < 0) { + printf("Failed to open the GPS serial!\n"); + return 1; + } + + printf("Sending autobaud...\n"); + rc = bcm4751_autobaud(fd); + if(fd < 0) { + printf("Failed to send autobaud!\n"); + return 1; + } + + bcm4751_read_dump(fd); + + return 0; +} |