usb: mtu3: support 36-bit DMA address

[mirror_ubuntu-bionic-kernel.git] / drivers / usb / mtu3 / mtu3_core.c

diff --git a/drivers/usb/mtu3/mtu3_core.c b/drivers/usb/mtu3/mtu3_core.c
index 947579842ad788cd8725b63ded83695908bf1631..cd4528f5f337669d5a34990a9526d056fe33494d 100644 (file)
--- a/drivers/usb/mtu3/mtu3_core.c
+++ b/drivers/usb/mtu3/mtu3_core.c
@@ -17,6 +17,7 @@
  *
  */
 
+#include <linux/dma-mapping.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/of_address.h>
@@ -759,7 +760,31 @@ static void mtu3_hw_exit(struct mtu3 *mtu)
        mtu3_mem_free(mtu);
 }
 
-/*-------------------------------------------------------------------------*/
+/**
+ * we set 32-bit DMA mask by default, here check whether the controller
+ * supports 36-bit DMA or not, if it does, set 36-bit DMA mask.
+ */
+static int mtu3_set_dma_mask(struct mtu3 *mtu)
+{
+       struct device *dev = mtu->dev;
+       bool is_36bit = false;
+       int ret = 0;
+       u32 value;
+
+       value = mtu3_readl(mtu->mac_base, U3D_MISC_CTRL);
+       if (value & DMA_ADDR_36BIT) {
+               is_36bit = true;
+               ret = dma_set_mask_and_coherent(dev, DMA_BIT_MASK(36));
+               /* If set 36-bit DMA mask fails, fall back to 32-bit DMA mask */
+               if (ret) {
+                       is_36bit = false;
+                       ret = dma_set_mask_and_coherent(dev, DMA_BIT_MASK(32));
+               }
+       }
+       dev_info(dev, "dma mask: %s bits\n", is_36bit ? "36" : "32");
+
+       return ret;
+}
 
 int ssusb_gadget_init(struct ssusb_mtk *ssusb)
 {
@@ -820,6 +845,12 @@ int ssusb_gadget_init(struct ssusb_mtk *ssusb)
                return ret;
        }
 
+       ret = mtu3_set_dma_mask(mtu);
+       if (ret) {
+               dev_err(dev, "mtu3 set dma_mask failed:%d\n", ret);
+               goto dma_mask_err;
+       }
+
        ret = devm_request_irq(dev, mtu->irq, mtu3_irq, 0, dev_name(dev), mtu);
        if (ret) {
                dev_err(dev, "request irq %d failed!\n", mtu->irq);
@@ -845,6 +876,7 @@ int ssusb_gadget_init(struct ssusb_mtk *ssusb)
 gadget_err:
        device_init_wakeup(dev, false);
 
+dma_mask_err:
 irq_err:
        mtu3_hw_exit(mtu);
        ssusb->u3d = NULL;