spi: rspi: Add DT support to DMA setup

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Mark Brown <broonie@linaro.org>

2 files changed, 28 insertions, 14 deletions

diff --git a/Documentation/devicetree/bindings/spi/spi-rspi.txt b/Documentation/devicetree/bindings/spi/spi-rspi.txt
index d57d82a74054..f9929aceeacc 100644
--- a/Documentation/devicetree/bindings/spi/spi-rspi.txt
+++ b/Documentation/devicetree/bindings/spi/spi-rspi.txt
@@ -30,6 +30,9 @@ Required properties:
 
 Optional properties:
 - clocks           : Must contain a reference to the functional clock.
+- dmas             : Must contain a list of two references to DMA specifiers,
+                     one for transmission, and one for reception.
+- dma-names        : Must contain a list of two DMA names, "tx" and "rx".
 
 Pinctrl properties might be needed, too.  See
 Documentation/devicetree/bindings/pinctrl/renesas,*.
@@ -58,4 +61,6 @@ Examples:
                 num-cs = <1>;
                 #address-cells = <1>;
                 #size-cells = <0>;
+                dmas = <&dmac0 0x17>, <&dmac0 0x18>;
+                dma-names = "tx", "rx";
         };
diff --git a/drivers/spi/spi-rspi.c b/drivers/spi/spi-rspi.c
index 6a4eb2d7f644..1da609e4491d 100644
--- a/drivers/spi/spi-rspi.c
+++ b/drivers/spi/spi-rspi.c
@@ -909,10 +909,11 @@ static struct dma_chan *rspi_request_dma_chan(struct device *dev,
         dma_cap_zero(mask);
         dma_cap_set(DMA_SLAVE, mask);
 
-        chan = dma_request_channel(mask, shdma_chan_filter,
-                                   (void *)(unsigned long)id);
+        chan = dma_request_slave_channel_compat(mask, shdma_chan_filter,
+                                (void *)(unsigned long)id, dev,
+                                dir == DMA_MEM_TO_DEV ? "tx" : "rx");
         if (!chan) {
-                dev_warn(dev, "dma_request_channel failed\n");
+                dev_warn(dev, "dma_request_slave_channel_compat failed\n");
                 return NULL;
         }
 
@@ -941,22 +942,30 @@ static int rspi_request_dma(struct device *dev, struct spi_master *master,
                             const struct resource *res)
 {
         const struct rspi_plat_data *rspi_pd = dev_get_platdata(dev);
+        unsigned int dma_tx_id, dma_rx_id;
+
+        if (dev->of_node) {
+                /* In the OF case we will get the slave IDs from the DT */
+                dma_tx_id = 0;
+                dma_rx_id = 0;
+        } else if (rspi_pd && rspi_pd->dma_tx_id && rspi_pd->dma_rx_id) {
+                dma_tx_id = rspi_pd->dma_tx_id;
+                dma_rx_id = rspi_pd->dma_rx_id;
+        } else {
+                /* The driver assumes no error. */
+                return 0;
+        }
 
-        if (!rspi_pd || !rspi_pd->dma_rx_id || !rspi_pd->dma_tx_id)
-                return 0;       /* The driver assumes no error. */
-
-        master->dma_rx = rspi_request_dma_chan(dev, DMA_DEV_TO_MEM,
-                                               rspi_pd->dma_rx_id,
+        master->dma_tx = rspi_request_dma_chan(dev, DMA_MEM_TO_DEV, dma_tx_id,
                                                res->start + RSPI_SPDR);
-        if (!master->dma_rx)
+        if (!master->dma_tx)
                 return -ENODEV;
 
-        master->dma_tx = rspi_request_dma_chan(dev, DMA_MEM_TO_DEV,
-                                               rspi_pd->dma_tx_id,
+        master->dma_rx = rspi_request_dma_chan(dev, DMA_DEV_TO_MEM, dma_rx_id,
                                                res->start + RSPI_SPDR);
-        if (!master->dma_tx) {
-                dma_release_channel(master->dma_rx);
-                master->dma_rx = NULL;
+        if (!master->dma_rx) {
+                dma_release_channel(master->dma_tx);
+                master->dma_tx = NULL;
                 return -ENODEV;
         }