staging: sbe-2t3e3: use -ve error return codes in dc_init_descriptor_list

the dc_init_descriptor_list actually returns a +ve error return codes,
which is abnormal as other functions in kernel return -ve error codes on
failure. so replace the return codes of this function with -ve values
to make the consistency with the other functions in kernel.

Also make the dc_init_descriptor_list static as its never called
anywhere except in this file and move the function prototype from the
headerfile into the c file as its referred only in this c file.
Signed-off-by: NDevendra Naga <devendra.aaru@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/sbe-2t3e3/2t3e3.h

@@ -789,7 +789,6 @@ void dc_restart(struct channel *);
 void dc_receiver_onoff(struct channel *, u32);
 void dc_transmitter_onoff(struct channel *, u32);
 void dc_set_loopback(struct channel *, u32);
-u32 dc_init_descriptor_list(struct channel *);
 void dc_clear_descriptor_list(struct channel *);
 void dc_drop_descriptor_list(struct channel *);
 void dc_set_output_port(struct channel *);

drivers/staging/sbe-2t3e3/dc.c

@@ -17,6 +17,8 @@
 #include "2t3e3.h"
 #include "ctrl.h"
 
+static int dc_init_descriptor_list(struct channel *sc);
+
 void dc_init(struct channel *sc)
 {
 	u32 val;
@@ -307,7 +309,7 @@ void dc_set_loopback(struct channel *sc, u32 mode)
 			      SBE_2T3E3_21143_VAL_FULL_DUPLEX_MODE);
 }
 
-u32 dc_init_descriptor_list(struct channel *sc)
+static int dc_init_descriptor_list(struct channel *sc)
 {
 	u32 i, j;
 	struct sk_buff *m;
@@ -317,7 +319,7 @@ u32 dc_init_descriptor_list(struct channel *sc)
 					    sizeof(t3e3_rx_desc_t), GFP_KERNEL);
 	if (sc->ether.rx_ring == NULL) {
 		dev_err(&sc->pdev->dev, "SBE 2T3E3: no buffer space for RX ring\n");
-		return ENOMEM;
+		return -ENOMEM;
 	}
 
 	if (sc->ether.tx_ring == NULL)
@@ -327,7 +329,7 @@ u32 dc_init_descriptor_list(struct channel *sc)
 		kfree(sc->ether.rx_ring);
 		sc->ether.rx_ring = NULL;
 		dev_err(&sc->pdev->dev, "SBE 2T3E3: no buffer space for RX ring\n");
-		return ENOMEM;
+		return -ENOMEM;
 	}
 
 
@@ -351,7 +353,7 @@ u32 dc_init_descriptor_list(struct channel *sc)
 				sc->ether.tx_ring = NULL;
 				dev_err(&sc->pdev->dev, "SBE 2T3E3: token_alloc err:"
 					" no buffer space for RX ring\n");
-				return ENOBUFS;
+				return -ENOBUFS;
 			}
 			sc->ether.rx_data[i] = m;
 		}