drv: reduce DMA transfer to maximum PAGE_SIZE

Apparently the gn4124 does not handle properly bigger pages. I think I have seen this before in the ADC and indeed thare we do PAGE_SIZE transfers. Signed-off-by: Federico Vaga <federico.vaga@cern.ch>

drv: reduce DMA transfer to maximum PAGE_SIZE
Apparently the gn4124 does not handle properly bigger pages. I think I have seen this before in the ADC and indeed thare we do PAGE_SIZE transfers. Signed-off-by: Federico Vaga <federico.vaga@cern.ch>
3edd1f2b · Federico Vaga · b4eb3036 · 3edd1f2b
Commit 3edd1f2b authored Aug 22, 2018 by Federico Vaga
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ft-irq.c kernel/ft-irq.c +1 -1

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--- a/kernel/ft-irq.c
+++ b/kernel/ft-irq.c
@@ -267,7 +267,7 @@ static void ft_readout_dma_start(struct fmctdc_dev *ft, int channel)
 	count = 0;
 	while (total > 0) {
 		cset->ti->nsamples  = min((unsigned long)total,
-					  KMALLOC_MAX_SIZE);
+					  PAGE_SIZE / cset->ssize);
 		zio_cset_busy_set(cset, 1);
 		zio_arm_trigger(cset->ti); /* actually a fire */
 		ft_readout_dma_run(cset, base_cur, count, cset->ti->nsamples);