+static int
+dma40_config_to_halfchannel(struct d40_chan *d40c,
+ struct stedma40_half_channel_info *info,
+ enum dma_slave_buswidth width,
+ u32 maxburst)
+{
+ enum stedma40_periph_data_width addr_width;
+ int psize;
+
+ switch (width) {
+ case DMA_SLAVE_BUSWIDTH_1_BYTE:
+ addr_width = STEDMA40_BYTE_WIDTH;
+ break;
+ case DMA_SLAVE_BUSWIDTH_2_BYTES:
+ addr_width = STEDMA40_HALFWORD_WIDTH;
+ break;
+ case DMA_SLAVE_BUSWIDTH_4_BYTES:
+ addr_width = STEDMA40_WORD_WIDTH;
+ break;
+ case DMA_SLAVE_BUSWIDTH_8_BYTES:
+ addr_width = STEDMA40_DOUBLEWORD_WIDTH;
+ break;
+ default:
+ dev_err(d40c->base->dev,
+ "illegal peripheral address width "
+ "requested (%d)\n",
+ width);
+ return -EINVAL;
+ }
+
+ if (chan_is_logical(d40c)) {
+ if (maxburst >= 16)
+ psize = STEDMA40_PSIZE_LOG_16;
+ else if (maxburst >= 8)
+ psize = STEDMA40_PSIZE_LOG_8;
+ else if (maxburst >= 4)
+ psize = STEDMA40_PSIZE_LOG_4;
+ else
+ psize = STEDMA40_PSIZE_LOG_1;
+ } else {
+ if (maxburst >= 16)
+ psize = STEDMA40_PSIZE_PHY_16;
+ else if (maxburst >= 8)
+ psize = STEDMA40_PSIZE_PHY_8;
+ else if (maxburst >= 4)
+ psize = STEDMA40_PSIZE_PHY_4;
+ else
+ psize = STEDMA40_PSIZE_PHY_1;
+ }
+
+ info->data_width = addr_width;
+ info->psize = psize;
+ info->flow_ctrl = STEDMA40_NO_FLOW_CTRL;
+
+ return 0;
+}
+