bmp280-orangepi.c

/* Copyright (c) 2016 Max Asaulov
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to
 * deal in the Software without restriction, including without limitation the
 * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
 * sell copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
 * IN THE SOFTWARE.
 */

#include <stdio.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <linux/i2c-dev.h>
#include <linux/i2c.h>
#include <errno.h>
#include <string.h>
#include <sys/ioctl.h>
#include <stdlib.h>
#include <stdint.h>
#include <unistd.h>
#include <math.h>
#include "bmp280.h"

#define PATH_STR   "/dev/i2c-0"

static const uint8_t addr_array[] = {0b1110110, 0b1110111};
static int file = -1;

 s8 BMP280_I2C_bus_write(u8 dev_addr, u8 reg_addr, u8 *reg_data, u8 cnt)
{
	struct i2c_rdwr_ioctl_data packets;
    	struct i2c_msg messages[1];
	u8 out_buff[sizeof(reg_addr) + cnt];
	out_buff[0] = reg_addr;
	memcpy(&out_buff[1], reg_data, cnt);

    	messages[0].addr  = dev_addr;
    	messages[0].flags = 0;
    	messages[0].len   = sizeof(out_buff);
    	messages[0].buf   = out_buff;

    	packets.msgs  = messages;
    	packets.nmsgs = 1;
    	if(ioctl(file, I2C_RDWR, &packets) < 0) {
        	return ERROR;
    	}

	return SUCCESS;
}

static s8 BMP280_I2C_bus_read(u8 dev_addr, u8 reg_addr, u8 *reg_data, u8 cnt)
{
        struct i2c_rdwr_ioctl_data packets;
        struct i2c_msg messages[2];

        messages[0].addr  = dev_addr;
        messages[0].flags = 0;
        messages[0].len   = sizeof(reg_addr);
        messages[0].buf   = &reg_addr;

        messages[1].addr  = dev_addr;
        messages[1].flags = I2C_M_RD | I2C_M_NOSTART;
        messages[1].len   = cnt;
        messages[1].buf   = reg_data;

        packets.msgs  = messages;
        packets.nmsgs = 2;
        if(ioctl(file, I2C_RDWR, &packets) < 0) {
                return ERROR;
        }

        return SUCCESS;
}

static void BMP280_delay_msec(BMP280_MDELAY_DATA_TYPE ms)
{
        usleep(ms*1000);
}

int main()
{
	printf("Starting test...\n");
	file = open(PATH_STR, O_RDWR);
	if (file < 0) {
		printf("Error opening a bus %s : %s\n", PATH_STR, strerror(errno));
		if (errno == EACCES) {
			printf("Try sudo\n");
		};
		exit(1);
	};
        struct bmp280_t bmp280;
        bmp280.bus_read = BMP280_I2C_bus_read;
        bmp280.bus_write = BMP280_I2C_bus_write;
        bmp280.delay_msec = BMP280_delay_msec;
	for (size_t i = 0; i < (sizeof(addr_array)/sizeof(addr_array[0])); i++) {
		bmp280.chip_id = 0xFF;
                bmp280.dev_addr = addr_array[i];
                s32 com_rslt = bmp280_init(&bmp280);
                printf("  > Testing 0x%2X -> %s\n", bmp280.dev_addr, (com_rslt == 0) ? "Found" : "Not found");
                if (com_rslt != 0) {
                        continue;
		}
		/* CP from template */
		/* The variable used to assign the standby time*/
		u8 v_standby_time_u8 = BMP280_INIT_VALUE;
		/* The variable used to read uncompensated temperature*/
		s32 v_data_uncomp_tem_s32 = BMP280_INIT_VALUE;
		/* The variable used to read uncompensated pressure*/
		s32 v_data_uncomp_pres_s32 = BMP280_INIT_VALUE;
		/* The variable used to read real temperature*/
		s32 v_actual_temp_s32 = BMP280_INIT_VALUE;
		/* The variable used to read real pressure*/
		u32 v_actual_press_u32 = BMP280_INIT_VALUE;
		s32 v_actual_press_data_s32 = BMP280_INIT_VALUE;
		/* result of communication results*/
		com_rslt += bmp280_set_power_mode(BMP280_NORMAL_MODE);
		com_rslt += bmp280_set_work_mode(BMP280_HIGH_RESOLUTION_MODE);
		com_rslt += bmp280_set_standby_durn(BMP280_STANDBY_TIME_1_MS);
		com_rslt += bmp280_read_pressure_temperature(&v_actual_press_u32,  &v_actual_temp_s32);
		if (com_rslt != 0) {
                	continue;
              	}
              	printf("   > Temp %i.%.2i C preassure  %i.%.2i millibar \n", v_actual_temp_s32/100,
                                                                          v_actual_temp_s32 % 100 ,
                                                                          v_actual_press_u32/100,
                                                                          v_actual_press_u32 % 100);
		com_rslt += bmp280_set_power_mode(BMP280_SLEEP_MODE);
	}
	
	close(file);
	return 0;
}