tools: iio: convert iio_generic_buffer to use new IIO buffer API
This change makes use of the new IIO buffer API to read data from an IIO
buffer.
It doesn't read the /sys/bus/iio/devices/iio:deviceX/scan_elements dir
anymore, it reads /sys/bus/iio/devices/iio:deviceX/bufferY, where all the
scan_elements have been merged together with the old/classical buffer
attributes.
And it makes use of the new IIO_BUFFER_GET_FD_IOCTL ioctl to get an FD for
the IIO buffer for which to read data from.
It also does a quick sanity check to see that -EBUSY is returned if reading
the chardev after the ioctl() has succeeded.
This was tested with the following cases:
1. Tested buffer0 works with ioctl()
2. Tested that buffer0 can't be opened via /dev/iio:deviceX after ioctl()
This check should be omitted under normal operation; it's being done
here to check that the driver change is sane
3. Moved valid buffer0 to be buffer1, and tested that data comes from it
Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
Link: https://lore.kernel.org/r/20210215104043.91251-25-alexandru.ardelean@analog.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
diff --git a/tools/iio/iio_utils.h b/tools/iio/iio_utils.h
index a5d0aa8..336752c 100644
--- a/tools/iio/iio_utils.h
+++ b/tools/iio/iio_utils.h
@@ -12,7 +12,7 @@
/* Made up value to limit allocation sizes */
#define IIO_MAX_NAME_LENGTH 64
-#define FORMAT_SCAN_ELEMENTS_DIR "%s/scan_elements"
+#define FORMAT_SCAN_ELEMENTS_DIR "%s/buffer%d"
#define FORMAT_TYPE_FILE "%s_type"
#define ARRAY_SIZE(arr) (sizeof(arr) / sizeof(arr[0]))
@@ -61,7 +61,7 @@ int iioutils_get_param_float(float *output, const char *param_name,
const char *device_dir, const char *name,
const char *generic_name);
void bsort_channel_array_by_index(struct iio_channel_info *ci_array, int cnt);
-int build_channel_array(const char *device_dir,
+int build_channel_array(const char *device_dir, int buffer_idx,
struct iio_channel_info **ci_array, int *counter);
int find_type_by_name(const char *name, const char *type);
int write_sysfs_int(const char *filename, const char *basedir, int val);