iio: trigger buffer samples fix

Signed-off-by: Lay, Kuan Loon <kuan.loon.lay@intel.com>
Signed-off-by: Brendan Le Foll <brendan.le.foll@intel.com>

diff --git a/src/iio/iio.c b/src/iio/iio.c
index 45427ff..7a00d5a 100644 (file)
--- a/src/iio/iio.c
+++ b/src/iio/iio.c
@@ -79,6 +79,9 @@ mraa_iio_get_channel_data(mraa_iio_context dev)
     int padint = 0;
     int curr_bytes = 0;
     char shortbuf, signchar;
+
+    dev->datasize = 0;
+
     memset(buf, 0, MAX_SIZE);
     snprintf(buf, MAX_SIZE, IIO_SYSFS_DEVICE "%d/" IIO_SCAN_ELEM, dev->num);
     dir = opendir(buf);
@@ -151,6 +154,10 @@ mraa_iio_get_channel_data(mraa_iio_context dev)
                         return -1;
                     }
                     chan->enabled = (int) strtol(readbuf, NULL, 10);
+                    //only calculate enable buffer size for trigger buffer extract data
+                    if (chan->enabled) {
+                        dev->datasize += chan->bytes;
+                    }
                     close(fd);
                 }
                 // clean up str var
@@ -158,7 +165,6 @@ mraa_iio_get_channel_data(mraa_iio_context dev)
             }
         }
     }
-    dev->datasize = curr_bytes;
 
     return MRAA_SUCCESS;
 }
@@ -224,7 +230,7 @@ mraa_iio_write(mraa_iio_context dev, const char* attr_chan, const char* data)
 }
 
 static mraa_result_t
-mraa_iio_wait_event(int fd, char* data)
+mraa_iio_wait_event(int fd, char* data, int *read_size)
 {
     struct pollfd pfd;
 
@@ -240,7 +246,7 @@ mraa_iio_wait_event(int fd, char* data)
     int x = poll(&pfd, 1, -1);
 
     memset(data, 0, 100);
-    read(fd, data, 100);
+    *read_size = read(fd, data, 100);
 
     return MRAA_SUCCESS;
 }
@@ -249,12 +255,17 @@ static void*
 mraa_iio_trigger_handler(void* arg)
 {
     mraa_iio_context dev = (mraa_iio_context) arg;
+    int i;
     char data[MAX_SIZE*100];
+    int read_size;
 
     for (;;) {
-        if (mraa_iio_wait_event(dev->fp, &data[0]) == MRAA_SUCCESS) {
+        if (mraa_iio_wait_event(dev->fp, &data[0], &read_size) == MRAA_SUCCESS) {
             pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, NULL);
-            dev->isr(&data);
+            //only can process if readsize >= enabled channel's datasize
+           for (i=0; i<(read_size/dev->datasize); i++) {
+                dev->isr(&data);
+            }
             pthread_setcancelstate(PTHREAD_CANCEL_ENABLE, NULL);
         } else {
             // we must have got an error code so die nicely