Merge tag 'usb-for-v4.2' of git://git.kernel.org/pub/scm/linux/kernel/git/balbi/usb...

[firefly-linux-kernel-4.4.55.git] / drivers / usb / renesas_usbhs / fifo.c

diff --git a/drivers/usb/renesas_usbhs/fifo.c b/drivers/usb/renesas_usbhs/fifo.c
index fa126a2b0c33c18ae174e57ce087bd1fe9f4cdff..c0f5c652d272c8959f5b3d59461e1af139d6f7fd 100644 (file)
--- a/drivers/usb/renesas_usbhs/fifo.c
+++ b/drivers/usb/renesas_usbhs/fifo.c
@@ -1239,15 +1239,21 @@ static void usbhsf_dma_init_dt(struct device *dev, struct usbhs_fifo *fifo,
 {
        char name[16];
 
-       snprintf(name, sizeof(name), "tx%d", channel);
-       fifo->tx_chan = dma_request_slave_channel_reason(dev, name);
-       if (IS_ERR(fifo->tx_chan))
-               fifo->tx_chan = NULL;
-
-       snprintf(name, sizeof(name), "rx%d", channel);
-       fifo->rx_chan = dma_request_slave_channel_reason(dev, name);
-       if (IS_ERR(fifo->rx_chan))
-               fifo->rx_chan = NULL;
+       /*
+        * To avoid complex handing for DnFIFOs, the driver uses each
+        * DnFIFO as TX or RX direction (not bi-direction).
+        * So, the driver uses odd channels for TX, even channels for RX.
+        */
+       snprintf(name, sizeof(name), "ch%d", channel);
+       if (channel & 1) {
+               fifo->tx_chan = dma_request_slave_channel_reason(dev, name);
+               if (IS_ERR(fifo->tx_chan))
+                       fifo->tx_chan = NULL;
+       } else {
+               fifo->rx_chan = dma_request_slave_channel_reason(dev, name);
+               if (IS_ERR(fifo->rx_chan))
+                       fifo->rx_chan = NULL;
+       }
 }
 
 static void usbhsf_dma_init(struct usbhs_priv *priv, struct usbhs_fifo *fifo,