7fb13f9f3d
Debian 10 (Buster) has gcc 8.2 which warns about: source/c_pwm.c:459:65: error: argument to ‘sizeof’ in ‘strncpy’ call is the same expression as the source; did you mean to use the size of the destination? [-Werror=sizeof-pointer-memaccess] source/c_pwm.c:396:43: error: ‘%s’ directive output may be truncated writing up to 199 bytes into a region of size 100 [-Werror=format-truncation=]
146 lines
3.7 KiB
C
146 lines
3.7 KiB
C
/*
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Copyright (c) 2013 Adafruit
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Author: Justin Cooper
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Permission is hereby granted, free of charge, to any person obtaining a copy of
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this software and associated documentation files (the "Software"), to deal in
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the Software without restriction, including without limitation the rights to
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use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
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of the Software, and to permit persons to whom the Software is furnished to do
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so, subject to the following conditions:
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The above copyright notice and this permission notice shall be included in all
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copies or substantial portions of the Software.
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THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
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AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
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OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
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SOFTWARE.
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*/
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#include <stdio.h>
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#include <stdlib.h>
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#include <sys/types.h>
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#include <string.h>
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#include <fcntl.h>
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#include <unistd.h>
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#include "c_adc.h"
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#include "common.h"
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#ifdef BBBVERSION41
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char adc_prefix_dir[49];
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#else
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char adc_prefix_dir[40];
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#endif
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int adc_initialized = 0;
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BBIO_err initialize_adc(void)
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{
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#ifdef BBBVERSION41
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char test_path[149];
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#else
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char test_path[140];
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#endif
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FILE *fh;
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BBIO_err err;
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if (adc_initialized) {
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return BBIO_OK;
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}
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#ifdef BBBVERSION41
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err = load_device_tree("BB-ADC");
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if (err == BBIO_OK) {
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strncat(adc_prefix_dir, "/sys/bus/iio/devices/iio:device0/in_voltage", sizeof(adc_prefix_dir));
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snprintf(test_path, sizeof(test_path), "%s%d_raw", adc_prefix_dir, 1);
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sleep(1);
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fh = fopen(test_path, "r");
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if (!fh) {
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return BBIO_SYSFS;
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}
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fclose(fh);
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adc_initialized = 1;
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return BBIO_OK;
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}
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#else
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err = load_device_tree("cape-bone-iio");
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if (err == BBIO_OK) {
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build_path("/sys/devices", "ocp.", ocp_dir, sizeof(ocp_dir));
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build_path(ocp_dir, "helper.", adc_prefix_dir, sizeof(adc_prefix_dir));
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strncat(adc_prefix_dir, "/AIN", sizeof(adc_prefix_dir));
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snprintf(test_path, sizeof(test_path), "%s%d", adc_prefix_dir, 0);
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fh = fopen(test_path, "r");
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if (!fh) {
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return BBIO_SYSFS;
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}
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fclose(fh);
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adc_initialized = 1;
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return BBIO_OK;
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}
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#endif
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return BBIO_GEN;
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}
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BBIO_err read_value(unsigned int ain, float *value)
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{
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FILE * fh;
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#ifdef BBBVERSION41
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char ain_path[149];
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snprintf(ain_path, sizeof(ain_path), "%s%d_raw", adc_prefix_dir, ain);
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#else
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char ain_path[140];
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snprintf(ain_path, sizeof(ain_path), "%s%d", adc_prefix_dir, ain);
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#endif
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int err, try_count=0;
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int read_successful;
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read_successful = 0;
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// Workaround to AIN bug where reading from more than one AIN would cause access failures
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while (!read_successful && try_count < 3)
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{
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fh = fopen(ain_path, "r");
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// Likely a bad path to the ocp device driver
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if (!fh) {
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return BBIO_SYSFS;
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}
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fseek(fh, 0, SEEK_SET);
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err = fscanf(fh, "%f", value);
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if (err != EOF) read_successful = 1;
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fclose(fh);
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try_count++;
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}
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if (read_successful) return BBIO_OK;
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// Fall through and fail
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return BBIO_GEN;
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}
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BBIO_err adc_setup(void)
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{
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return initialize_adc();
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}
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BBIO_err adc_cleanup(void)
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{
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#ifdef BBBVERSION41
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return unload_device_tree("BB-ADC");
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#else
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return unload_device_tree("cape-bone-iio");
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#endif
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}
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