dmaengine: rcar-dmac: Use of_data values instead of a macro

Since we will have changed memory mapping of the DMAC in the future,
this patch uses of_data values instead of a macro to calculate
each channel's base offset.
Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Link: https://lore.kernel.org/r/1568010892-17606-3-git-send-email-yoshihiro.shimoda.uh@renesas.comSigned-off-by: Vinod Koul <vkoul@kernel.org>

drivers/dma/sh/rcar-dmac.c

@@ -210,12 +210,20 @@ struct rcar_dmac {
 
 #define to_rcar_dmac(d)		container_of(d, struct rcar_dmac, engine)
 
+/*
+ * struct rcar_dmac_of_data - This driver's OF data
+ * @chan_offset_base: DMAC channels base offset
+ * @chan_offset_stride: DMAC channels offset stride
+ */
+struct rcar_dmac_of_data {
+	u32 chan_offset_base;
+	u32 chan_offset_stride;
+};
+
 /* -----------------------------------------------------------------------------
  * Registers
  */
 
-#define RCAR_DMAC_CHAN_OFFSET(i)	(0x8000 + 0x80 * (i))
-
 #define RCAR_DMAISTA			0x0020
 #define RCAR_DMASEC			0x0030
 #define RCAR_DMAOR			0x0060
@@ -1726,6 +1734,7 @@ static const struct dev_pm_ops rcar_dmac_pm = {
 
 static int rcar_dmac_chan_probe(struct rcar_dmac *dmac,
 				struct rcar_dmac_chan *rchan,
+				const struct rcar_dmac_of_data *data,
 				unsigned int index)
 {
 	struct platform_device *pdev = to_platform_device(dmac->dev);
@@ -1735,7 +1744,8 @@ static int rcar_dmac_chan_probe(struct rcar_dmac *dmac,
 	int ret;
 
 	rchan->index = index;
-	rchan->iomem = dmac->iomem + RCAR_DMAC_CHAN_OFFSET(index);
+	rchan->iomem = dmac->iomem + data->chan_offset_base +
+		       data->chan_offset_stride * index;
 	rchan->mid_rid = -EINVAL;
 
 	spin_lock_init(&rchan->lock);
@@ -1813,10 +1823,15 @@ static int rcar_dmac_probe(struct platform_device *pdev)
 		DMA_SLAVE_BUSWIDTH_32_BYTES | DMA_SLAVE_BUSWIDTH_64_BYTES;
 	struct dma_device *engine;
 	struct rcar_dmac *dmac;
+	const struct rcar_dmac_of_data *data;
 	struct resource *mem;
 	unsigned int i;
 	int ret;
 
+	data = of_device_get_match_data(&pdev->dev);
+	if (!data)
+		return -EINVAL;
+
 	dmac = devm_kzalloc(&pdev->dev, sizeof(*dmac), GFP_KERNEL);
 	if (!dmac)
 		return -ENOMEM;
@@ -1901,7 +1916,7 @@ static int rcar_dmac_probe(struct platform_device *pdev)
 		if (!(dmac->channels_mask & BIT(i)))
 			continue;
 
-		ret = rcar_dmac_chan_probe(dmac, &dmac->channels[i], i);
+		ret = rcar_dmac_chan_probe(dmac, &dmac->channels[i], data, i);
 		if (ret < 0)
 			goto error;
 	}
@@ -1948,8 +1963,16 @@ static void rcar_dmac_shutdown(struct platform_device *pdev)
 	rcar_dmac_stop_all_chan(dmac);
 }
 
+static const struct rcar_dmac_of_data rcar_dmac_data = {
+	.chan_offset_base = 0x8000,
+	.chan_offset_stride = 0x80,
+};
+
 static const struct of_device_id rcar_dmac_of_ids[] = {
-	{ .compatible = "renesas,rcar-dmac", },
+	{
+		.compatible = "renesas,rcar-dmac",
+		.data = &rcar_dmac_data,
+	},
 	{ /* Sentinel */ }
 };
 MODULE_DEVICE_TABLE(of, rcar_dmac_of_ids);