net: pegasus: Use the new usb control message API.

The old usb_control_msg() let the caller handle the error and also did not
account for partial reads.  Since these are now considered harmful, move the
driver over to usb_control_msg_recv/send() calls.

Added small note about why set_registers() can't be used to substitute
set_register().

Signed-off-by: Petko Manolov <petko.manolov@konsulko.com>
Acked-by: David S. Miller <davem@davemloft.net>
Link: https://lore.kernel.org/r/20200927124909.16380-2-petko.manolov@konsulko.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/net/usb/pegasus.c b/drivers/net/usb/pegasus.c
index e92cb51a2c77028b8c2f05b923bcda8312313be6..26b4e48bf91ff50e573e70788d03cd6740a843a8 100644 (file)
--- a/drivers/net/usb/pegasus.c
+++ b/drivers/net/usb/pegasus.c
@@ -124,62 +124,31 @@ static void async_ctrl_callback(struct urb *urb)
 
 static int get_registers(pegasus_t *pegasus, __u16 indx, __u16 size, void *data)
 {
-       u8 *buf;
-       int ret;
-
-       buf = kmalloc(size, GFP_NOIO);
-       if (!buf)
-               return -ENOMEM;
-
-       ret = usb_control_msg(pegasus->usb, usb_rcvctrlpipe(pegasus->usb, 0),
-                             PEGASUS_REQ_GET_REGS, PEGASUS_REQT_READ, 0,
-                             indx, buf, size, 1000);
-       if (ret < 0)
-               netif_dbg(pegasus, drv, pegasus->net,
-                         "%s returned %d\n", __func__, ret);
-       else if (ret <= size)
-               memcpy(data, buf, ret);
-       kfree(buf);
-       return ret;
+       return usb_control_msg_recv(pegasus->usb, 0, PEGASUS_REQ_GET_REGS,
+                                  PEGASUS_REQT_READ, 0, indx, data, size,
+                                  1000, GFP_NOIO);
 }
 
 static int set_registers(pegasus_t *pegasus, __u16 indx, __u16 size,
                         const void *data)
 {
-       u8 *buf;
-       int ret;
-
-       buf = kmemdup(data, size, GFP_NOIO);
-       if (!buf)
-               return -ENOMEM;
-
-       ret = usb_control_msg(pegasus->usb, usb_sndctrlpipe(pegasus->usb, 0),
-                             PEGASUS_REQ_SET_REGS, PEGASUS_REQT_WRITE, 0,
-                             indx, buf, size, 100);
-       if (ret < 0)
-               netif_dbg(pegasus, drv, pegasus->net,
-                         "%s returned %d\n", __func__, ret);
-       kfree(buf);
-       return ret;
+       return usb_control_msg_send(pegasus->usb, 0, PEGASUS_REQ_SET_REGS,
+                                   PEGASUS_REQT_WRITE, 0, indx, data, size,
+                                   1000, GFP_NOIO);
 }
 
+/*
+ * There is only one way to write to a single ADM8511 register and this is via
+ * specific control request.  'data' is ignored by the device, but it is here to
+ * not break the API.
+ */
 static int set_register(pegasus_t *pegasus, __u16 indx, __u8 data)
 {
-       u8 *buf;
-       int ret;
-
-       buf = kmemdup(&data, 1, GFP_NOIO);
-       if (!buf)
-               return -ENOMEM;
+       void *buf = &data;
 
-       ret = usb_control_msg(pegasus->usb, usb_sndctrlpipe(pegasus->usb, 0),
-                             PEGASUS_REQ_SET_REG, PEGASUS_REQT_WRITE, data,
-                             indx, buf, 1, 1000);
-       if (ret < 0)
-               netif_dbg(pegasus, drv, pegasus->net,
-                         "%s returned %d\n", __func__, ret);
-       kfree(buf);
-       return ret;
+       return usb_control_msg_send(pegasus->usb, 0, PEGASUS_REQ_SET_REG,
+                                   PEGASUS_REQT_WRITE, data, indx, buf, 1,
+                                   1000, GFP_NOIO);
 }
 
 static int update_eth_regs_async(pegasus_t *pegasus)