recuperation des sample par l'application de test

adxl345.c

@@ -81,29 +81,63 @@ static struct Sample fifo_pop(struct Fifo *f) {
 // Fonctions ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 
 ssize_t adxl345_read(struct file *file, char __user *buf, size_t count, loff_t *f_pos){
+
+    char nsample;
+    char rest;
+    unsigned char res[count];
+    int i=0;
+    int16_t direction_sample;
+    struct Sample sample;
+
     // TODO: permetre de choisir l'axe de lecture
-    pr_info("In adxl345_read function\n");
+    //pr_info("In adxl345_read function\n");
 
     // Recuperation de la structure adxl345
     struct adxl345_device *d = container_of(file->private_data,struct adxl345_device,miscdev);
-    pr_info("Got pointer to adxl345_device structure\n");
+    //pr_info("Got pointer to adxl345_device structure\n");
 
-    int nsample = fifo_len(&(d->fifo));
-    pr_info("Got %i sample in the FIFO\n",nsample);
-
-    struct Sample sample;
-    int i;
-    for(i=count; i<0; i--){
-        sample = fifo_pop(&(d->fifo));
-        pr_info("Sample %i: (%i,%i,%i)\n",i,sample.x,sample.y,sample.z);
+    // Compute the number of complete samples (6 bytes) to get
+    nsample = count/6;
+    rest = count%6;
+    // Adjust what to get depending on the number of sample in the fifo
+    if(fifo_len(&(d->fifo))<=nsample){
+        nsample = fifo_len(&(d->fifo));
+        rest = 0;
     }
 
+    //pr_info("%i sample in fifo\nGetting %i full sample ans %i more bytes\n",fifo_len(&(d->fifo)),nsample,rest);
 
+    // Get the full samples
+    for(i=0;i<nsample;i++){
+        //pr_info("Getting sample %i\n",i);
+        sample = fifo_pop(&(d->fifo));
+        res[i*6+1] = (unsigned char) (sample.x>>8);
+        res[i*6+0] = (unsigned char) (sample.x & 0x00ff);
+        res[i*6+3] = (unsigned char) (sample.y>>8);
+        res[i*6+2] = (unsigned char) (sample.y & 0x00ff);
+        res[i*6+5] = (unsigned char) (sample.z>>8);
+        res[i*6+4] = (unsigned char) (sample.z & 0x00ff);
+        //pr_info("%i %i %i\n",sample.x,sample.y,sample.z);
+        //pr_info("%x %x %x %x\n",res[i], res[i+1], res[i+2],res[i+3]);
+    }
+
+    // Get the rest
+    sample = fifo_pop(&(d->fifo));
+    for(i=nsample*6;i<nsample*6+rest;i++){
+        //pr_info("Getting Byte %i/%i\n",i,nsample*6+rest);
+        // Get the correct direction
+        if(i-nsample*6<2){direction_sample = sample.x;} // X
+        else if(i-nsample*6<4){direction_sample = sample.y;} // Y
+        else{direction_sample = sample.z;} // Z
+        // Extract the correct byte from the direction sample
+        res[i] = direction_sample & (0xff<<(i%2)*2);
+    }
     
     // Ecriture du resultat dans le buffer de retour
-    //copy_to_user(buf, response, 1);
+    //pr_info("%x %x %x %x\n",res[3], res[2], res[1],res[0]);
+    copy_to_user(buf, res, nsample*6+rest);
 
-    return (ssize_t)1;
+    return (ssize_t)nsample*6+rest;
 }
 
 irq_handler_t adxl345_int(int irq, struct adxl345_device * d){