kernel: directly count trigger sample as post_sample

It should make the code clear since the +1 and -1 (for the trigger sample) is done only when accessing the hardware. Otherwise, we cansider the trigger sample as part of the post samples Signed-off-by: Federico Vaga <federico.vaga@cern.ch> Signed-off-by: Dimitris Lampridis <Dimitris.Lampridis@cern.ch>

kernel: directly count trigger sample as post_sample
It should make the code clear since the +1 and -1 (for the trigger sample) is done only when accessing the hardware. Otherwise, we cansider the trigger sample as part of the post samples Signed-off-by: Federico Vaga <federico.vaga@cern.ch> Signed-off-by: Dimitris Lampridis <Dimitris.Lampridis@cern.ch>
22a66c15 · Federico Vaga · 68ca1db3 · 22a66c15 · 22a66c15 · 22a66c15
Commit 22a66c15 authored Apr 19, 2016 by Federico Vaga
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Showing with 11 additions and 16 deletions

fa-irq.c kernel/fa-irq.c +2 -6

fa-zio-trg.c kernel/fa-zio-trg.c +8 -7

fmc-adc-100m14b4cha.h kernel/fmc-adc-100m14b4cha.h +1 -3

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--- a/kernel/fa-irq.c
+++ b/kernel/fa-irq.c
@@ -143,12 +143,8 @@ void zfad_dma_done(struct zio_cset *cset)
 		ctrl->attr_channel.ext_val[FA100M14B4C_DATTR_ACQ_START_F] =
 								ztstamp.bins;
-		/*
+		/* resize the datalen, by removing the trigger tstamp */
-		 * resize the datalen, by removing the trigger tstamp and the
+		block->datalen = block->datalen - FA_TRIG_TIMETAG_BYTES;
-		 * extra samples (trigger samples, 1 for each channel)
-		 */
-		block->datalen = block->datalen - FA_TRIG_TIMETAG_BYTES
-					- (ctrl->ssize * FA100M14B4C_NCHAN);
 		/* update seq num */
 		ctrl->seq_num = i;

--- a/kernel/fa-zio-trg.c
+++ b/kernel/fa-zio-trg.c
@@ -109,10 +109,11 @@ static int zfat_conf_set(struct device *dev, struct zio_attribute *zattr,
 		}
 		break;
 	case ZFAT_POST:
-		if (!tmp_val) {
+		if (tmp_val < 2) {
-			dev_err(dev, "post samples cannot be 0 (minimum 1)\n");
+			dev_err(dev, "minimum post samples 2 (HW limitation)\n");
 			return -EINVAL;
 		}
+		tmp_val--;  /* Remove one sample for the trigger */
 		break;
 	case ZFAT_SW:
 		/* Fire if software trigger is enabled (index 5) */
@@ -163,9 +164,13 @@ static int zfat_info_get(struct device *dev, struct zio_attribute *zattr,
 	*usr_val = fa_readl(fa, fa->fa_adc_csr_base, &zfad_regs[zattr->id]);
 	switch (zattr->id) {
+	case ZFAT_POST:
+		(*usr_val)++; /* add the trigger sample */
+		break;
 	case ZFAT_DLY:
 		/* Add channel signal transmission delay */
 		*usr_val -= fa->trig_compensation;
+		break;
 	}
 	return 0;
@@ -339,12 +344,8 @@ static int zfat_arm_trigger(struct zio_ti *ti)
 	 * (4*32bits word) size should be 32bits word aligned
 	 * ti->nsamples is the sum of (pre-samp+ post-samp)*4chan
 	 * because it's the interleave channel.
-	 *
-	 * +FA_NCHAN because of the trigger samples (1 for each channel) which
-	 * will discard later on DMA done (Actually, we will discard the last
-	 * post-sample because we count the trigger sample as post-sample)
 	 */
-	size = (interleave->current_ctrl->ssize * (ti->nsamples + FA100M14B4C_NCHAN))
+	size = (interleave->current_ctrl->ssize * ti->nsamples)
 		+ FA_TRIG_TIMETAG_BYTES;
 	/* check if size is 32 bits word aligned: should be always the case */
 	if (size % 4) {

--- a/kernel/fmc-adc-100m14b4cha.h
+++ b/kernel/fmc-adc-100m14b4cha.h
@@ -423,11 +423,9 @@ static inline int zfat_overflow_detection(struct zio_ti *ti, unsigned int addr,
 			  ti_zattr[ZIO_ATTR_TRIG_N_SHOTS].value;
 	/*
-	 * +1 because of the trigger samples, which is not counted as
-	 * post-sample by the ADC
 	 * +2 because of the timetag at the end
 	 */
-	nsamples = pre_t + post_t + 1;
+	nsamples = pre_t + post_t;
 	shot_size = ((nsamples + 2) * ti->cset->ssize) * FA100M14B4C_NCHAN;
 	if ( (shot_size * nshot_t) > FA100M14B4C_MAX_ACQ_BYTE ) {
 		dev_err(&ti->head.dev, "Cannot acquire, dev memory overflow\n");