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Commit 9d8ae6c8 authored by Jonathan Cameron's avatar Jonathan Cameron Committed by Greg Kroah-Hartman
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staging:iio:Documentation: Rewrite example for new abi. 

Signed-off-by: default avatarJonathan Cameron <jic23@cam.ac.uk>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@suse.de>
parent e9124afa
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Showing with 313 additions and 198 deletions
drivers/staging/iio/Documentation/iio_utils.h
View file @ 9d8ae6c8
......@@ -7,140 +7,173 @@
* the Free Software Foundation.
*/
/* Made up value to limit allocation sizes */
#include <string.h>
#include <stdlib.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
const char *iio_dir = "/sys/bus/iio/devices/";
struct iio_event_data {
int id;
__s64 timestamp;
};
inline char *find_ring_subelement(const char *directory, const char *subelement)
{
DIR *dp;
const struct dirent *ent;
int pos;
char temp[100];
char *returnstring;
dp = opendir(directory);
if (dp == NULL) {
printf("could not directory: %s\n", directory);
return NULL;
}
while (ent = readdir(dp), ent != NULL) {
if (strcmp(ent->d_name, ".") != 0 &&
strcmp(ent->d_name, "..") != 0) {
if (strncmp(ent->d_name, subelement, strlen(subelement)) == 0) {
int length = sprintf(temp, "%s%s%s", directory, ent->d_name, "/");
returnstring = malloc(length+1);
strncpy(returnstring, temp, length+1);
return returnstring;
}
}
}
return 0;
}
char *find_type_by_name(const char *name, const char *type)
/**
* 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
*
* Typical types this is used for are device and trigger.
**/
inline int find_type_by_name(const char *name, const char *type)
{
const char *iio_dir = "/sys/bus/iio/devices/";
const struct dirent *ent;
int cnt, pos, pos2;
int number, numstrlen;
FILE *nameFile;
DIR *dp;
char thisname[100];
char temp[100];
char *returnstring = NULL;
char thisname[IIO_MAX_NAME_LENGTH];
char *filename;
struct stat Stat;
pos = sprintf(temp, "%s", iio_dir);
dp = opendir(iio_dir);
if (dp == NULL) {
printf("No industrialio devices available");
return NULL;
return -ENODEV;
}
while (ent = readdir(dp), ent != NULL) {
cnt++;
/*reject . and .. */
if (strcmp(ent->d_name, ".") != 0 &&
strcmp(ent->d_name, "..") != 0) {
/*make sure it isn't a trigger!*/
if (strncmp(ent->d_name, type, strlen(type)) == 0) {
/* build full path to new file */
pos2 = pos + sprintf(temp + pos, "%s/", ent->d_name);
sprintf(temp + pos2, "name");
printf("search location %s\n", temp);
nameFile = fopen(temp, "r");
if (!nameFile) {
sprintf(temp + pos2, "modalias", ent->d_name);
nameFile = fopen(temp, "r");
if (!nameFile) {
printf("Failed to find a name for device\n");
return NULL;
}
}
strcmp(ent->d_name, "..") != 0 &&
strlen(ent->d_name) > strlen(type) &&
strncmp(ent->d_name, type, strlen(type)) == 0) {
numstrlen = sscanf(ent->d_name + strlen(type),
"%d",
&number);
/* verify the next character is not a colon */
if (strncmp(ent->d_name + strlen(type) + numstrlen,
":",
1) != 0) {
filename = malloc(strlen(iio_dir)
+ strlen(type)
+ 1
+ numstrlen
+ 1);
if (filename == NULL)
return -ENOMEM;
sprintf(filename, "%s%s%d/name",
iio_dir,
type,
number);
nameFile = fopen(filename, "r");
if (!nameFile)
continue;
free(filename);
fscanf(nameFile, "%s", thisname);
if (strcmp(name, thisname) == 0) {
returnstring = malloc(strlen(temp) + 1);
sprintf(temp + pos2, "");
strcpy(returnstring, temp);
return returnstring;
}
if (strcmp(name, thisname) == 0)
return number;
fclose(nameFile);
}
}
}
return -ENODEV;
}
int write_sysfs_int(char *filename, char *basedir, int val)
inline int _write_sysfs_int(char *filename, char *basedir, int val, int verify)
{
int ret;
FILE *sysfsfp;
char temp[100];
sprintf(temp, "%s%s", basedir, filename);
FILE *sysfsfp;
int test;
char *temp = malloc(strlen(basedir) + strlen(filename) + 2);
if (temp == NULL)
return -ENOMEM;
sprintf(temp, "%s/%s", basedir, filename);
sysfsfp = fopen(temp, "w");
if (sysfsfp == NULL)
return -1;
if (sysfsfp == NULL) {
printf("failed to open %s\n", temp);
ret = -errno;
goto error_free;
}
fprintf(sysfsfp, "%d", val);
fclose(sysfsfp);
return 0;
if (verify) {
sysfsfp = fopen(temp, "r");
if (sysfsfp == NULL) {
printf("failed to open %s\n", temp);
ret = -errno;
goto error_free;
}
fscanf(sysfsfp, "%d", &test);
if (test != val) {
printf("Possible failure in int write %d to %s%s\n",
val,
basedir,
filename);
ret = -1;
}
}
error_free:
free(temp);
return ret;
}
int write_sysfs_int(char *filename, char *basedir, int val)
{
return _write_sysfs_int(filename, basedir, val, 0);
}
int write_sysfs_int_and_verify(char *filename, char *basedir, int val)
{
return _write_sysfs_int(filename, basedir, val, 1);
}
int _write_sysfs_string(char *filename, char *basedir, char *val, int verify)
{
int ret;
FILE *sysfsfp;
char temp[100];
int test;
sprintf(temp, "%s%s", basedir, filename);
char *temp = malloc(strlen(basedir) + strlen(filename) + 2);
if (temp == NULL) {
printf("Memory allocation failed\n");
return -ENOMEM;
}
sprintf(temp, "%s/%s", basedir, filename);
sysfsfp = fopen(temp, "w");
if (sysfsfp == NULL)
return -1;
fprintf(sysfsfp, "%d", val);
if (sysfsfp == NULL) {
printf("Could not open %s\n", temp);
ret = -errno;
goto error_free;
}
fprintf(sysfsfp, "%s", val);
fclose(sysfsfp);
sysfsfp = fopen(temp, "r");
if (sysfsfp == NULL)
return -1;
fscanf(sysfsfp, "%d", &test);
if (test != val) {
printf("Possible failure in int write %d to %s%s\n",
val,
basedir,
filename);
return -1;
if (verify) {
sysfsfp = fopen(temp, "r");
if (sysfsfp == NULL) {
ret = -errno;
goto error_free;
}
fscanf(sysfsfp, "%s", temp);
if (strcmp(temp, val) != 0) {
printf("Possible failure in string write of %s "
"Should be %s "
"writen to %s\%s\n",
temp,
val,
basedir,
filename);
ret = -1;
}
}
error_free:
free(temp);
return 0;
return ret;
}
/**
* write_sysfs_string_and_verify() - string write, readback and verify
* @filename: name of file to write to
......@@ -149,40 +182,54 @@ int write_sysfs_int_and_verify(char *filename, char *basedir, int val)
**/
int write_sysfs_string_and_verify(char *filename, char *basedir, char *val)
{
int ret;
FILE *sysfsfp;
char temp[100];
sprintf(temp, "%s%s", basedir, filename);
sysfsfp = fopen(temp, "w");
if (sysfsfp == NULL)
return -1;
fprintf(sysfsfp, "%s", val);
fclose(sysfsfp);
return _write_sysfs_string(filename, basedir, val, 1);
}
sysfsfp = fopen(temp, "r");
if (sysfsfp == NULL)
return -1;
fscanf(sysfsfp, "%s", temp);
if (strcmp(temp, val) != 0) {
printf("Possible failure in string write %s to %s%s \n",
val,
basedir,
filename);
return -1;
}
return 0;
int write_sysfs_string(char *filename, char *basedir, char *val)
{
return _write_sysfs_string(filename, basedir, val, 0);
}
int read_sysfs_posint(char *filename, char *basedir)
{
int ret;
FILE *sysfsfp;
char temp[100];
sprintf(temp, "%s%s", basedir, filename);
char *temp = malloc(strlen(basedir) + strlen(filename) + 2);
if (temp == NULL) {
printf("Memory allocation failed");
return -ENOMEM;
}
sprintf(temp, "%s/%s", basedir, filename);
sysfsfp = fopen(temp, "r");
if (sysfsfp == NULL)
return -1;
if (sysfsfp == NULL) {
ret = -errno;
goto error_free;
}
fscanf(sysfsfp, "%d\n", &ret);
fclose(sysfsfp);
error_free:
free(temp);
return ret;
}
int read_sysfs_float(char *filename, char *basedir, float *val)
{
float ret = 0;
FILE *sysfsfp;
char *temp = malloc(strlen(basedir) + strlen(filename) + 2);
if (temp == NULL) {
printf("Memory allocation failed");
return -ENOMEM;
}
sprintf(temp, "%s/%s", basedir, filename);
sysfsfp = fopen(temp, "r");
if (sysfsfp == NULL) {
ret = -errno;
goto error_free;
}
fscanf(sysfsfp, "%f\n", val);
fclose(sysfsfp);
error_free:
free(temp);
return ret;
}
drivers/staging/iio/Documentation/lis3l02dqbuffersimple.c
View file @ 9d8ae6c8
/* Industrialio test ring buffer with a lis3l02dq acceleromter
/* Industrialio ring buffer with a lis3l02dq accelerometer
*
* Copyright (c) 2008 Jonathan Cameron
*
......@@ -6,125 +6,181 @@
* under the terms of the GNU General Public License version 2 as published by
* the Free Software Foundation.
*
* Assumes suitable udev rules are used to create the dev nodes as named here.
* This program is primarily intended as an example application.
*/
#include <dirent.h>
#include <fcntl.h>
#include <stdio.h>
#include <errno.h>
#include <stdint.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/dir.h>
#include <linux/types.h>
#include "iio_utils.h"
static const char *ring_access = "/dev/iio/lis3l02dq_ring_access";
static const char *ring_event = "/dev/iio/lis3l02dq_ring_event";
static const char *device_name = "lis3l02dq";
static const char *trigger_name = "lis3l02dq-dev0";
static int NumVals = 3;
static int scan_ts = 1;
static int RingLength = 128;
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
* 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 numVals, int timestamp)
int size_from_scanmode(int num_vals, int timestamp)
{
if (numVals && timestamp)
if (num_vals && timestamp)
return 16;
else if (timestamp)
return 8;
else
return numVals*2;
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;
char *BaseDirectoryName,
*TriggerDirectoryName,
*RingBufferDirectoryName;
BaseDirectoryName = find_type_by_name(device_name, "device");
if (BaseDirectoryName == NULL) {
printf("Failed to find the %s \n", device_name);
return -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;
}
TriggerDirectoryName = find_type_by_name(trigger_name, "trigger");
if (TriggerDirectoryName == NULL) {
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);
return -1;
ret = -ENODEV;
goto error_free_triggername;
}
RingBufferDirectoryName = find_ring_subelement(BaseDirectoryName,
"ring_buffer");
if (RingBufferDirectoryName == NULL) {
printf("Failed to find ring buffer\n");
return -1;
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;
}
if (write_sysfs_string_and_verify("trigger/current_trigger",
BaseDirectoryName,
(char *)trigger_name) < 0) {
printf("Failed to write current_trigger file \n");
return -1;
/* 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 */
if (write_sysfs_int("length", RingBufferDirectoryName,
RingLength) < 0) {
printf("Failed to open the ring buffer length file \n");
return -1;
}
ret = write_sysfs_int("length", buf_dir_name, buf_len);
if (ret < 0)
goto error_free_buf_dir_name;
/* Enable the ring buffer */
if (write_sysfs_int("ring_enable", RingBufferDirectoryName, 1) < 0) {
printf("Failed to open the ring buffer control file \n");
return -1;
};
/* Enable the buffer */
ret = write_sysfs_int("ring_enable", buf_dir_name, 1);
if (ret < 0)
goto error_free_buf_dir_name;
data = malloc(size_from_scanmode(NumVals, scan_ts)*RingLength);
data = malloc(size_from_scanmode(num_vals, scan_ts)*buf_len);
if (!data) {
printf("Could not allocate space for usespace data store\n");
return -1;
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(ring_access, O_RDONLY | O_NONBLOCK);
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", ring_access);
return -1;
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(ring_event, "rb");
fp_ev = fopen(buffer_event, "rb");
if (fp_ev == NULL) {
printf("Failed to open %s\n", ring_event);
return -1;
printf("Failed to open %s\n", buffer_event);
ret = -errno;
goto error_close_buffer_access;
}
/* Wait for events 10 times */
for (j = 0; j < 10; j++) {
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 = RingLength;
toread = buf_len;
break;
case IIO_EVENT_CODE_RING_75_FULL:
toread = RingLength*3/4;
toread = buf_len*3/4;
break;
case IIO_EVENT_CODE_RING_50_FULL:
toread = RingLength/2;
toread = buf_len/2;
break;
default:
printf("Unexpecteded event code\n");
......@@ -132,39 +188,51 @@ int main(int argc, char **argv)
}
read_size = read(fp,
data,
toread*size_from_scanmode(NumVals, scan_ts));
toread*size_from_scanmode(num_vals, scan_ts));
if (read_size == -EAGAIN) {
printf("nothing available \n");
printf("nothing available\n");
continue;
}
for (i = 0;
i < read_size/size_from_scanmode(NumVals, scan_ts);
i++) {
for (k = 0; k < NumVals; k++) {
__s16 val = *(__s16 *)(&data[i*size_from_scanmode(NumVals, scan_ts)
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("%05d ", val);
printf("%05f ", (float)val*gain);
}
printf(" %lld\n",
*(__s64 *)(&data[(i+1)*size_from_scanmode(NumVals, scan_ts)
*(__s64 *)(&data[(i + 1)
*size_from_scanmode(num_vals,
scan_ts)
- sizeof(__s64)]));
}
}
/* Stop the ring buffer */
if (write_sysfs_int("ring_enable", RingBufferDirectoryName, 0) < 0) {
printf("Failed to open the ring buffer control file \n");
return -1;
};
/* Disconnect from the trigger - writing something that doesn't exist.*/
write_sysfs_string_and_verify("trigger/current_trigger",
BaseDirectoryName, "NULL");
free(BaseDirectoryName);
free(TriggerDirectoryName);
free(RingBufferDirectoryName);
ret = write_sysfs_int("ring_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);
return 0;
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;
}
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