net/usb/r815x: replace USB buffer from stack to DMA-able

Some USB buffers use stack which may not be DMA-able.
Use the buffers from kmalloc to replace those one.

Signed-off-by: Hayes Wang <hayeswang@realtek.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/usb/r815x.c b/drivers/net/usb/r815x.c
index 8523922..e9b99ba 100644 (file)
--- a/drivers/net/usb/r815x.c
+++ b/drivers/net/usb/r815x.c
@@ -24,34 +24,43 @@
 
 static int pla_read_word(struct usb_device *udev, u16 index)
 {
-       int data, ret;
+       int ret;
        u8 shift = index & 2;
-       __le32 ocp_data;
+       __le32 *tmp;
+
+       tmp = kmalloc(sizeof(*tmp), GFP_KERNEL);
+       if (!tmp)
+               return -ENOMEM;
 
        index &= ~3;
 
        ret = usb_control_msg(udev, usb_rcvctrlpipe(udev, 0),
                              RTL815x_REQ_GET_REGS, RTL815x_REQT_READ,
-                             index, MCU_TYPE_PLA, &ocp_data, sizeof(ocp_data),
-                             500);
+                             index, MCU_TYPE_PLA, tmp, sizeof(*tmp), 500);
        if (ret < 0)
-               return ret;
+               goto out2;
 
-       data = __le32_to_cpu(ocp_data);
-       data >>= (shift * 8);
-       data &= 0xffff;
+       ret = __le32_to_cpu(*tmp);
+       ret >>= (shift * 8);
+       ret &= 0xffff;
 
-       return data;
+out2:
+       kfree(tmp);
+       return ret;
 }
 
 static int pla_write_word(struct usb_device *udev, u16 index, u32 data)
 {
-       __le32 ocp_data;
+       __le32 *tmp;
        u32 mask = 0xffff;
        u16 byen = BYTE_EN_WORD;
        u8 shift = index & 2;
        int ret;
 
+       tmp = kmalloc(sizeof(*tmp), GFP_KERNEL);
+       if (!tmp)
+               return -ENOMEM;
+
        data &= mask;
 
        if (shift) {
@@ -63,19 +72,20 @@ static int pla_write_word(struct usb_device *udev, u16 index, u32 data)
 
        ret = usb_control_msg(udev, usb_rcvctrlpipe(udev, 0),
                              RTL815x_REQ_GET_REGS, RTL815x_REQT_READ,
-                             index, MCU_TYPE_PLA, &ocp_data, sizeof(ocp_data),
-                             500);
+                             index, MCU_TYPE_PLA, tmp, sizeof(*tmp), 500);
        if (ret < 0)
-               return ret;
+               goto out3;
 
-       data |= __le32_to_cpu(ocp_data) & ~mask;
-       ocp_data = __cpu_to_le32(data);
+       data |= __le32_to_cpu(*tmp) & ~mask;
+       *tmp = __cpu_to_le32(data);
 
        ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
                              RTL815x_REQ_SET_REGS, RTL815x_REQT_WRITE,
-                             index, MCU_TYPE_PLA | byen, &ocp_data,
-                             sizeof(ocp_data), 500);
+                             index, MCU_TYPE_PLA | byen, tmp, sizeof(*tmp),
+                             500);
 
+out3:
+       kfree(tmp);
        return ret;
 }