diff options
Diffstat (limited to 'drivers/staging/iio/Documentation/iio_utils.h')
| -rw-r--r-- | drivers/staging/iio/Documentation/iio_utils.h | 396 |
1 files changed, 391 insertions, 5 deletions
diff --git a/drivers/staging/iio/Documentation/iio_utils.h b/drivers/staging/iio/Documentation/iio_utils.h index 014f6684..0372424 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 |
