diff options
| -rw-r--r-- | drivers/staging/iio/Documentation/generic_buffer.c | 318 | ||||
| -rw-r--r-- | drivers/staging/iio/Documentation/iio_utils.h | 396 | ||||
| -rw-r--r-- | drivers/staging/iio/Documentation/lis3l02dqbuffersimple.c | 238 |
3 files changed, 709 insertions, 243 deletions
diff --git a/drivers/staging/iio/Documentation/generic_buffer.c b/drivers/staging/iio/Documentation/generic_buffer.c new file mode 100644 index 000000000000..df23aeb9d529 --- /dev/null +++ b/drivers/staging/iio/Documentation/generic_buffer.c @@ -0,0 +1,318 @@ +/* Industrialio buffer test code. + * + * Copyright (c) 2008 Jonathan Cameron + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 as published by + * the Free Software Foundation. + * + * This program is primarily intended as an example application. + * Reads the current buffer setup from sysfs and starts a short capture + * from the specified device, pretty printing the result after appropriate + * conversion. + * + * Command line parameters + * generic_buffer -n <device_name> -t <trigger_name> + * If trigger name is not specified the program assumes you want a dataready + * trigger associated with the device and goes looking for it. + * + */ + +#include <unistd.h> +#include <dirent.h> +#include <fcntl.h> +#include <stdio.h> +#include <errno.h> +#include <sys/stat.h> +#include <sys/dir.h> +#include <linux/types.h> +#include "iio_utils.h" + +const int buf_len = 128; +const int num_loops = 2; + +/** + * size_from_channelarray() - calculate the storage size of a scan + * @channels: the channel info array + * @num_channels: size of the channel info array + * + * Has the side effect of filling the channels[i].location values used + * in processing the buffer output. + **/ +int size_from_channelarray(struct iio_channel_info *channels, int num_channels) +{ + int bytes = 0; + int i = 0; + while (i < num_channels) { + if (bytes % channels[i].bytes == 0) + channels[i].location = bytes; + else + channels[i].location = bytes - bytes%channels[i].bytes + + channels[i].bytes; + bytes = channels[i].location + channels[i].bytes; + i++; + } + return bytes; +} + +/** + * process_scan() - print out the values in SI units + * @data: pointer to the start of the scan + * @infoarray: information about the channels. Note + * size_from_channelarray must have been called first to fill the + * location offsets. + * @num_channels: the number of active channels + **/ +void process_scan(char *data, + struct iio_channel_info *infoarray, + int num_channels) +{ + int k; + for (k = 0; k < num_channels; k++) + switch (infoarray[k].bytes) { + /* only a few cases implemented so far */ + case 2: + if (infoarray[k].is_signed) { + int16_t val = *(int16_t *) + (data + + infoarray[k].location); + if ((val >> infoarray[k].bits_used) & 1) + val = (val & infoarray[k].mask) | + ~infoarray[k].mask; + printf("%05f ", ((float)val + + infoarray[k].offset)* + infoarray[k].scale); + } else { + uint16_t val = *(uint16_t *) + (data + + infoarray[k].location); + val = (val & infoarray[k].mask); + printf("%05f ", ((float)val + + infoarray[k].offset)* + infoarray[k].scale); + } + break; + case 8: + if (infoarray[k].is_signed) { + int64_t val = *(int64_t *) + (data + + infoarray[k].location); + if ((val >> infoarray[k].bits_used) & 1) + val = (val & infoarray[k].mask) | + ~infoarray[k].mask; + /* special case for timestamp */ + if (infoarray[k].scale == 1.0f && + infoarray[k].offset == 0.0f) + printf(" %lld", val); + else + printf("%05f ", ((float)val + + infoarray[k].offset)* + infoarray[k].scale); + } + break; + default: + break; + } + printf("\n"); +} + +int main(int argc, char **argv) +{ + int ret, c, i, j, toread; + + FILE *fp_ev; + int fp; + + int num_channels; + char *trigger_name = NULL, *device_name = NULL; + char *dev_dir_name, *buf_dir_name; + + int datardytrigger = 1; + char *data; + size_t read_size; + struct iio_event_data dat; + int dev_num, trig_num; + char *buffer_access, *buffer_event; + int scan_size; + + struct iio_channel_info *infoarray; + + while ((c = getopt(argc, argv, "t:n:")) != -1) { + switch (c) { + case 'n': + device_name = optarg; + break; + case 't': + trigger_name = optarg; + datardytrigger = 0; + break; + case '?': + return -1; + } + } + + /* Find the device requested */ + dev_num = find_type_by_name(device_name, "device"); + if (dev_num < 0) { + printf("Failed to find the %s\n", device_name); + ret = -ENODEV; + goto error_ret; + } + printf("iio device number being used is %d\n", dev_num); + + asprintf(&dev_dir_name, "%sdevice%d", iio_dir, dev_num); + if (trigger_name == NULL) { + /* + * Build the trigger name. If it is device associated it's + * name is <device_name>_dev[n] where n matches the device + * number found above + */ + ret = asprintf(&trigger_name, + "%s-dev%d", device_name, dev_num); + if (ret < 0) { + ret = -ENOMEM; + goto error_ret; + } + } + + /* Verify the trigger exists */ + trig_num = find_type_by_name(trigger_name, "trigger"); + if (trig_num < 0) { + printf("Failed to find the trigger %s\n", trigger_name); + ret = -ENODEV; + goto error_free_triggername; + } + printf("iio trigger number being used is %d\n", trig_num); + + /* + * Parse the files in scan_elements to identify what channels are + * present + */ + ret = build_channel_array(dev_dir_name, &infoarray, &num_channels); + if (ret) { + printf("Problem reading scan element information \n"); + goto error_free_triggername; + } + + /* + * Construct the directory name for the associated buffer. + * As we know that the lis3l02dq has only one buffer this may + * be built rather than found. + */ + ret = asprintf(&buf_dir_name, "%sdevice%d:buffer0", iio_dir, dev_num); + if (ret < 0) { + ret = -ENOMEM; + goto error_free_triggername; + } + printf("%s %s\n", dev_dir_name, trigger_name); + /* Set the device trigger to be the data rdy trigger found above */ + ret = write_sysfs_string_and_verify("trigger/current_trigger", + dev_dir_name, + trigger_name); + if (ret < 0) { + printf("Failed to write current_trigger file\n"); + goto error_free_buf_dir_name; + } + + /* Setup ring buffer parameters */ + ret = write_sysfs_int("length", buf_dir_name, buf_len); + if (ret < 0) + goto error_free_buf_dir_name; + + /* Enable the buffer */ + ret = write_sysfs_int("enable", buf_dir_name, 1); + if (ret < 0) + goto error_free_buf_dir_name; + scan_size = size_from_channelarray(infoarray, num_channels); + data = malloc(scan_size*buf_len); + if (!data) { + ret = -ENOMEM; + goto error_free_buf_dir_name; + } + + ret = asprintf(&buffer_access, + "/dev/device%d:buffer0:access0", + dev_num); + if (ret < 0) { + ret = -ENOMEM; + goto error_free_data; + } + + ret = asprintf(&buffer_event, "/dev/device%d:buffer0:event0", dev_num); + if (ret < 0) { + ret = -ENOMEM; + goto error_free_buffer_access; + } + /* Attempt to open non blocking the access dev */ + fp = open(buffer_access, O_RDONLY | O_NONBLOCK); + if (fp == -1) { /*If it isn't there make the node */ + printf("Failed to open %s\n", buffer_access); + ret = -errno; + goto error_free_buffer_event; + } + /* Attempt to open the event access dev (blocking this time) */ + fp_ev = fopen(buffer_event, "rb"); + if (fp_ev == NULL) { + printf("Failed to open %s\n", buffer_event); + ret = -errno; + goto error_close_buffer_access; + } + + /* Wait for events 10 times */ + for (j = 0; j < num_loops; j++) { + read_size = fread(&dat, 1, sizeof(struct iio_event_data), + fp_ev); + switch (dat.id) { + case IIO_EVENT_CODE_RING_100_FULL: + toread = buf_len; + break; + case IIO_EVENT_CODE_RING_75_FULL: + toread = buf_len*3/4; + break; + case IIO_EVENT_CODE_RING_50_FULL: + toread = buf_len/2; + break; + default: + printf("Unexpecteded event code\n"); + continue; + } + read_size = read(fp, + data, + toread*scan_size); + if (read_size == -EAGAIN) { + printf("nothing available\n"); + continue; + } + for (i = 0; i < read_size/scan_size; i++) + process_scan(data + scan_size*i, + infoarray, + num_channels); + } + + /* Stop the ring buffer */ + ret = write_sysfs_int("enable", buf_dir_name, 0); + if (ret < 0) + goto error_close_buffer_event; + + /* Disconnect from the trigger - just write a dummy name.*/ + write_sysfs_string("trigger/current_trigger", + dev_dir_name, "NULL"); + +error_close_buffer_event: + fclose(fp_ev); +error_close_buffer_access: + close(fp); +error_free_data: + free(data); +error_free_buffer_access: + free(buffer_access); +error_free_buffer_event: + free(buffer_event); +error_free_buf_dir_name: + free(buf_dir_name); +error_free_triggername: + if (datardytrigger) + free(trigger_name); +error_ret: + return ret; +} diff --git a/drivers/staging/iio/Documentation/iio_utils.h b/drivers/staging/iio/Documentation/iio_utils.h index 014f6684faba..03724246b95a 100644 --- a/drivers/staging/iio/Documentation/iio_utils.h +++ b/drivers/staging/iio/Documentation/iio_utils.h @@ -10,12 +10,23 @@ /* Made up value to limit allocation sizes */ #include <string.h> #include <stdlib.h> +#include <ctype.h> +#include <stdio.h> +#include <stdint.h> #define IIO_MAX_NAME_LENGTH 30 -#define IIO_EVENT_CODE_RING_50_FULL 200 -#define IIO_EVENT_CODE_RING_75_FULL 201 -#define IIO_EVENT_CODE_RING_100_FULL 202 +#define IIO_EV_CLASS_BUFFER 0 +#define IIO_BUFFER_EVENT_CODE(code) \ + (IIO_EV_CLASS_BUFFER | (code << 8)) + +#define IIO_EVENT_CODE_RING_50_FULL IIO_BUFFER_EVENT_CODE(0) +#define IIO_EVENT_CODE_RING_75_FULL IIO_BUFFER_EVENT_CODE(1) +#define IIO_EVENT_CODE_RING_100_FULL IIO_BUFFER_EVENT_CODE(2) + + +#define FORMAT_SCAN_ELEMENTS_DIR "%s:buffer0/scan_elements" +#define FORMAT_TYPE_FILE "%s_type" const char *iio_dir = "/sys/bus/iio/devices/"; @@ -25,6 +36,380 @@ struct iio_event_data { }; /** + * iioutils_break_up_name() - extract generic name from full channel name + * @full_name: the full channel name + * @generic_name: the output generic channel name + **/ +static int iioutils_break_up_name(const char *full_name, + char **generic_name) +{ + char *current; + char *w, *r; + char *working; + current = strdup(full_name); + working = strtok(current, "_\0"); + w = working; + r = working; + + while(*r != '\0') { + if (!isdigit(*r)) { + *w = *r; + w++; + } + r++; + } + *w = '\0'; + *generic_name = strdup(working); + free(current); + + return 0; +} + +/** + * struct iio_channel_info - information about a given channel + * @name: channel name + * @generic_name: general name for channel type + * @scale: scale factor to be applied for conversion to si units + * @offset: offset to be applied for conversion to si units + * @index: the channel index in the buffer output + * @bytes: number of bytes occupied in buffer output + * @mask: a bit mask for the raw output + * @is_signed: is the raw value stored signed + * @enabled: is this channel enabled + **/ +struct iio_channel_info { + char *name; + char *generic_name; + float scale; + float offset; + unsigned index; + unsigned bytes; + unsigned bits_used; + uint64_t mask; + unsigned is_signed; + unsigned enabled; + unsigned location; +}; + +/** + * iioutils_get_type() - find and process _type attribute data + * @is_signed: output whether channel is signed + * @bytes: output how many bytes the channel storage occupies + * @mask: output a bit mask for the raw data + * @device_dir: the iio device directory + * @name: the channel name + * @generic_name: the channel type name + **/ +inline int iioutils_get_type(unsigned *is_signed, + unsigned *bytes, + unsigned *bits_used, + uint64_t *mask, + const char *device_dir, + const char *name, + const char *generic_name) +{ + FILE *sysfsfp; + int ret; + DIR *dp; + char *scan_el_dir, *builtname, *builtname_generic, *filename = 0; + char signchar; + unsigned sizeint, padint; + const struct dirent *ent; + + ret = asprintf(&scan_el_dir, FORMAT_SCAN_ELEMENTS_DIR, device_dir); + if (ret < 0) { + ret = -ENOMEM; + goto error_ret; + } + ret = asprintf(&builtname, FORMAT_TYPE_FILE, name); + if (ret < 0) { + ret = -ENOMEM; + goto error_free_scan_el_dir; + } + ret = asprintf(&builtname_generic, FORMAT_TYPE_FILE, generic_name); + if (ret < 0) { + ret = -ENOMEM; + goto error_free_builtname; + } + + dp = opendir(scan_el_dir); + if (dp == NULL) { + ret = -errno; + goto error_free_builtname_generic; + } + while (ent = readdir(dp), ent != NULL) + /* + * Do we allow devices to override a generic name with + * a specific one? + */ + if ((strcmp(builtname, ent->d_name) == 0) || + (strcmp(builtname_generic, ent->d_name) == 0)) { + ret = asprintf(&filename, + "%s/%s", scan_el_dir, ent->d_name); + if (ret < 0) { + ret = -ENOMEM; + goto error_closedir; + } + sysfsfp = fopen(filename, "r"); + if (sysfsfp == NULL) { + printf("failed to open %s\n", filename); + ret = -errno; + goto error_free_filename; + } + fscanf(sysfsfp, + "%c%u/%u", &signchar, bits_used, &padint); + *bytes = padint / 8; + if (sizeint == 64) + *mask = ~0; + else + *mask = (1 << *bits_used) - 1; + if (signchar == 's') + *is_signed = 1; + else + *is_signed = 0; + } +error_free_filename: + if (filename) + free(filename); +error_closedir: + closedir(dp); +error_free_builtname_generic: + free(builtname_generic); +error_free_builtname: + free(builtname); +error_free_scan_el_dir: + free(scan_el_dir); +error_ret: + return ret; +} + +inline int iioutils_get_param_float(float *output, + const char *param_name, + const char *device_dir, + const char *name, + const char *generic_name) +{ + FILE *sysfsfp; + int ret; + DIR *dp; + char *builtname, *builtname_generic; + char *filename = NULL; + const struct dirent *ent; + + ret = asprintf(&builtname, "%s_%s", name, param_name); + if (ret < 0) { + ret = -ENOMEM; + goto error_ret; + } + ret = asprintf(&builtname_generic, + "%s_%s", generic_name, param_name); + if (ret < 0) { + ret = -ENOMEM; + goto error_free_builtname; + } + dp = opendir(device_dir); + if (dp == NULL) { + ret = -errno; + goto error_free_builtname_generic; + } + while (ent = readdir(dp), ent != NULL) + if ((strcmp(builtname, ent->d_name) == 0) || + (strcmp(builtname_generic, ent->d_name) == 0)) { + ret = asprintf(&filename, + "%s/%s", device_dir, ent->d_name); + if (ret < 0) { + ret = -ENOMEM; + goto error_closedir; + } + sysfsfp = fopen(filename, "r"); + if (!sysfsfp) { + ret = -errno; + goto error_free_filename; + } + fscanf(sysfsfp, "%f", output); + break; + } +error_free_filename: + if (filename) + free(filename); +error_closedir: + closedir(dp); +error_free_builtname_generic: + free(builtname_generic); +error_free_builtname: + free(builtname); +error_ret: + return ret; +} + + +/** + * build_channel_array() - function to figure out what channels are present + * @device_dir: the IIO device directory in sysfs + * @ + **/ +inline int build_channel_array(const char *device_dir, + struct iio_channel_info **ci_array, + int *counter) +{ + DIR *dp; + FILE *sysfsfp; + int count = 0, temp, i; + struct iio_channel_info *current; + int ret; + const struct dirent *ent; + char *scan_el_dir; + char *filename; + + *counter = 0; + ret = asprintf(&scan_el_dir, FORMAT_SCAN_ELEMENTS_DIR, device_dir); + if (ret < 0) { + ret = -ENOMEM; + goto error_ret; + } + dp = opendir(scan_el_dir); + if (dp == NULL) { + ret = -errno; + goto error_free_name; + } + while (ent = readdir(dp), ent != NULL) + if (strcmp(ent->d_name + strlen(ent->d_name) - strlen("_en"), + "_en") == 0) { + ret = asprintf(&filename, + "%s/%s", scan_el_dir, ent->d_name); + if (ret < 0) { + ret = -ENOMEM; + goto error_close_dir; + } + sysfsfp = fopen(filename, "r"); + if (sysfsfp == NULL) { + ret = -errno; + free(filename); + goto error_close_dir; + } + fscanf(sysfsfp, "%u", &ret); + if (ret == 1) + (*counter)++; + fclose(sysfsfp); + free(filename); + } + *ci_array = malloc(sizeof(**ci_array)*(*counter)); + if (*ci_array == NULL) { + ret = -ENOMEM; + goto error_close_dir; + } + seekdir(dp, 0); + while (ent = readdir(dp), ent != NULL) { + if (strcmp(ent->d_name + strlen(ent->d_name) - strlen("_en"), + "_en") == 0) { + current = &(*ci_array)[count++]; + ret = asprintf(&filename, + "%s/%s", scan_el_dir, ent->d_name); + if (ret < 0) { + ret = -ENOMEM; + /* decrement count to avoid freeing name */ + count--; + goto error_cleanup_array; + } + sysfsfp = fopen(filename, "r"); + if (sysfsfp == NULL) { + free(filename); + ret = -errno; + goto error_cleanup_array; + } + fscanf(sysfsfp, "%u", ¤t->enabled); + fclose(sysfsfp); + free(filename); + current->scale = 1.0; + current->offset = 0; + current->name = strndup(ent->d_name, + strlen(ent->d_name) - + strlen("_en")); + if (current->name == NULL) { + free(filename); + ret = -ENOMEM; + goto error_cleanup_array; + } + /* Get the generic and specific name elements */ + ret = iioutils_break_up_name(current->name, + ¤t->generic_name); + if (ret) { + free(filename); + goto error_cleanup_array; + } + ret = asprintf(&filename, + "%s/%s_index", + scan_el_dir, + current->name); + if (ret < 0) { + free(filename); + ret = -ENOMEM; + goto error_cleanup_array; + } + sysfsfp = fopen(filename, "r"); + fscanf(sysfsfp, "%u", ¤t->index); + fclose(sysfsfp); + free(filename); + /* Find the scale */ + ret = iioutils_get_param_float(¤t->scale, + "scale", + device_dir, + current->name, + current->generic_name); + if (ret < 0) + goto error_cleanup_array; + ret = iioutils_get_param_float(¤t->offset, + "offset", + device_dir, + current->name, + current->generic_name); + if (ret < 0) + goto error_cleanup_array; + ret = iioutils_get_type(¤t->is_signed, + ¤t->bytes, + ¤t->bits_used, + ¤t->mask, + device_dir, + current->name, + current->generic_name); + } + } + /* reorder so that the array is in index order*/ + current = malloc(sizeof(**ci_array)**counter); + if (current == NULL) { + ret = -ENOMEM; + goto error_cleanup_array; + } + closedir(dp); + count = 0; + temp = 0; + while (count < *counter) + for (i = 0; i < *counter; i++) + if ((*ci_array)[i].index == temp) { + memcpy(¤t[count++], + &(*ci_array)[i], + sizeof(*current)); + temp++; + break; + } + free(*ci_array); + *ci_array = current; + + return 0; + +error_cleanup_array: + for (i = count - 1; i >= 0; i++) + free((*ci_array)[i].name); + free(*ci_array); +error_close_dir: + closedir(dp); +error_free_name: + free(scan_el_dir); +error_ret: + return ret; +} + +/** * find_type_by_name() - function to match top level types by name * @name: top level type instance name * @type: the type of top level instance being sort @@ -40,7 +425,6 @@ inline int find_type_by_name(const char *name, const char *type) DIR *dp; char thisname[IIO_MAX_NAME_LENGTH]; char *filename; - struct stat Stat; dp = opendir(iio_dir); if (dp == NULL) { @@ -134,7 +518,7 @@ int write_sysfs_int_and_verify(char *filename, char *basedir, int val) int _write_sysfs_string(char *filename, char *basedir, char *val, int verify) { - int ret; + int ret = 0; FILE *sysfsfp; char *temp = malloc(strlen(basedir) + strlen(filename) + 2); if (temp == NULL) { @@ -153,6 +537,7 @@ int _write_sysfs_string(char *filename, char *basedir, char *val, int verify) if (verify) { sysfsfp = fopen(temp, "r"); if (sysfsfp == NULL) { + printf("could not open file to verify\n"); ret = -errno; goto error_free; } @@ -173,6 +558,7 @@ error_free: return ret; } + /** * write_sysfs_string_and_verify() - string write, readback and verify * @filename: name of file to write to diff --git a/drivers/staging/iio/Documentation/lis3l02dqbuffersimple.c b/drivers/staging/iio/Documentation/lis3l02dqbuffersimple.c deleted file mode 100644 index 2fc3fd81a7a7..000000000000 --- a/drivers/staging/iio/Documentation/lis3l02dqbuffersimple.c +++ /dev/null @@ -1,238 +0,0 @@ -/* Industrialio ring buffer with a lis3l02dq accelerometer - * - * Copyright (c) 2008 Jonathan Cameron - * - * This program is free software; you can redistribute it and/or modify it - * under the terms of the GNU General Public License version 2 as published by - * the Free Software Foundation. - * - * This program is primarily intended as an example application. - */ - -#include <dirent.h> -#include <fcntl.h> -#include <stdio.h> -#include <errno.h> -#include <sys/stat.h> -#include <sys/dir.h> -#include <linux/types.h> -#include "iio_utils.h" - -const char *device_name = "lis3l02dq"; -const char *trigger_name_base = "lis3l02dq-dev"; -const int num_vals = 3; -const int scan_ts = 1; -const int buf_len = 128; -const int num_loops = 10; - -/* - * Could get this from ring bps, but only after starting the ring - * which is a bit late for it to be useful. - * - * Todo: replace with much more generic version based on scan_elements - * directory. - */ -int size_from_scanmode(int num_vals, int timestamp) -{ - if (num_vals && timestamp) - return 16; - else if (timestamp) - return 8; - else - return num_vals*2; -} - -int main(int argc, char **argv) -{ - int ret; - int i, j, k, toread; - FILE *fp_ev; - int fp; - - char *trigger_name, *dev_dir_name, *buf_dir_name; - char *data; - size_t read_size; - struct iio_event_data dat; - int dev_num, trig_num; - - char *buffer_access, *buffer_event; - const char *iio_dir = "/sys/bus/iio/devices/"; - int scan_size; - float gain = 1; - - - /* Find out which iio device is the accelerometer. */ - dev_num = find_type_by_name(device_name, "device"); - if (dev_num < 0) { - printf("Failed to find the %s\n", device_name); - ret = -ENODEV; - goto error_ret; - } - printf("iio device number being used is %d\n", dev_num); - asprintf(&dev_dir_name, "%sdevice%d", iio_dir, dev_num); - - /* - * Build the trigger name. - * In this case we want the lis3l02dq's data ready trigger - * for this lis3l02dq. The naming is lis3l02dq_dev[n], where - * n matches the device number found above. - */ - ret = asprintf(&trigger_name, "%s%d", trigger_name_base, dev_num); - if (ret < 0) { - ret = -ENOMEM; - goto error_free_dev_dir_name; - } - - /* - * Find the trigger by name. - * This is techically unecessary here as we only need to - * refer to the trigger by name and that name is already - * known. - */ - trig_num = find_type_by_name(trigger_name, "trigger"); - if (trig_num < 0) { - printf("Failed to find the %s\n", trigger_name); - ret = -ENODEV; - goto error_free_triggername; - } - printf("iio trigger number being used is %d\n", trig_num); - - /* - * Read in the scale value - in a more generic case, first - * check for accel_scale, then the indivual channel scales - */ - ret = read_sysfs_float("accel_scale", dev_dir_name, &gain); - if (ret) - goto error_free_triggername;; - - /* - * Construct the directory name for the associated buffer. - * As we know that the lis3l02dq has only one buffer this may - * be built rather than found. - */ - ret = asprintf(&buf_dir_name, "%sdevice%d:buffer0", iio_dir, dev_num); - if (ret < 0) { - ret = -ENOMEM; - goto error_free_triggername; - } - /* Set the device trigger to be the data rdy trigger found above */ - ret = write_sysfs_string_and_verify("trigger/current_trigger", - dev_dir_name, - trigger_name); - if (ret < 0) { - printf("Failed to write current_trigger file\n"); - goto error_free_buf_dir_name; - } - - /* Setup ring buffer parameters */ - ret = write_sysfs_int("length", buf_dir_name, buf_len); - if (ret < 0) - goto error_free_buf_dir_name; - - /* Enable the buffer */ - ret = write_sysfs_int("enable", buf_dir_name, 1); - if (ret < 0) - goto error_free_buf_dir_name; - - data = malloc(size_from_scanmode(num_vals, scan_ts)*buf_len); - if (!data) { - ret = -ENOMEM; - goto error_free_buf_dir_name; - } - - ret = asprintf(&buffer_access, - "/dev/device%d:buffer0:access0", - dev_num); - if (ret < 0) { - ret = -ENOMEM; - goto error_free_data; - } - - ret = asprintf(&buffer_event, "/dev/device%d:buffer0:event0", dev_num); - if (ret < 0) { - ret = -ENOMEM; - goto error_free_data; - } - /* Attempt to open non blocking the access dev */ - fp = open(buffer_access, O_RDONLY | O_NONBLOCK); - if (fp == -1) { /*If it isn't there make the node */ - printf("Failed to open %s\n", buffer_access); - ret = -errno; - goto error_free_buffer_event; - } - /* Attempt to open the event access dev (blocking this time) */ - fp_ev = fopen(buffer_event, "rb"); - if (fp_ev == NULL) { - printf("Failed to open %s\n", buffer_event); - ret = -errno; - goto error_close_buffer_access; - } - - /* Wait for events 10 times */ - for (j = 0; j < num_loops; j++) { - read_size = fread(&dat, 1, sizeof(struct iio_event_data), - fp_ev); - switch (dat.id) { - case IIO_EVENT_CODE_RING_100_FULL: - toread = buf_len; - break; - case IIO_EVENT_CODE_RING_75_FULL: - toread = buf_len*3/4; - break; - case IIO_EVENT_CODE_RING_50_FULL: - toread = buf_len/2; - break; - default: - printf("Unexpecteded event code\n"); - continue; - } - read_size = read(fp, - data, - toread*size_from_scanmode(num_vals, scan_ts)); - if (read_size == -EAGAIN) { - printf("nothing available\n"); - continue; - } - scan_size = size_from_scanmode(num_vals, scan_ts); - for (i = 0; i < read_size/scan_size; i++) { - for (k = 0; k < num_vals; k++) { - __s16 val = *(__s16 *)(&data[i*scan_size - + (k)*2]); - printf("%05f ", (float)val*gain); - } - printf(" %lld\n", - *(__s64 *)(&data[(i + 1) - *size_from_scanmode(num_vals, - scan_ts) - - sizeof(__s64)])); - } - } - - /* Stop the ring buffer */ - ret = write_sysfs_int("enable", buf_dir_name, 0); - if (ret < 0) - goto error_close_buffer_event; - - /* Disconnect from the trigger - just write a dummy name.*/ - write_sysfs_string("trigger/current_trigger", - dev_dir_name, "NULL"); - -error_close_buffer_event: - fclose(fp_ev); -error_close_buffer_access: - close(fp); -error_free_data: - free(data); -error_free_buffer_access: - free(buffer_access); -error_free_buffer_event: - free(buffer_event); -error_free_buf_dir_name: - free(buf_dir_name); -error_free_triggername: - free(trigger_name); -error_free_dev_dir_name: - free(dev_dir_name); -error_ret: - return ret; -} |