[PATCH 1/2] staging: r8712u: Most return-values changed from -1 to proper errno macros.

[Ali Bahar <ali@internetdog.org>]

The ioctl handlers were frequently returning -1 upon failure. Most of
these have now been changed to proper errno macros.
The few remaining ones have been left untouched because either the
handler is not called (and so cannot be tested), or the function never
fails (and so cannot be system-tested), or requires new code to
distinguish its failures.

Signed-off-by: Ali Bahar <ali@internetDog.org>
Cc: Larry Finger <Larry.Finger@lwfinger.net>
---
 drivers/staging/rtl8712/rtl871x_ioctl_linux.c |  121 +++++++++++++++++++++----
 1 files changed, 105 insertions(+), 16 deletions(-)

diff --git a/drivers/staging/rtl8712/rtl871x_ioctl_linux.c b/drivers/staging/rtl8712/rtl871x_ioctl_linux.c
index 40e6b5c..bb97d8b 100644
--- a/drivers/staging/rtl8712/rtl871x_ioctl_linux.c
+++ b/drivers/staging/rtl8712/rtl871x_ioctl_linux.c
@@ -526,7 +526,7 @@ static int r871x_set_wpa_ie(struct _adapter *padapter, char *pie,
 		memcpy(buf, pie , ielen);
 		pos = buf;
 		if (ielen < RSN_HEADER_LEN) {
-			ret  = -1;
+			ret  = -EINVAL;
 			goto exit;
 		}
 		if (r8712_parse_wpa_ie(buf, ielen, &group_cipher,
@@ -689,6 +689,11 @@ static const long frequency_list[] = {
 	5825
 };
 
+/*
+ * This function intends to handle the Set Freq command.
+ * Currently, the request comes via the Wireless Extensions' SIOCSIWFREQ ioctl.
+ *
+ */
 static int r8711_wx_set_freq(struct net_device *dev,
 			     struct iw_request_info *info,
 			     union iwreq_data *wrqu, char *extra)
@@ -723,6 +728,11 @@ static int r8711_wx_set_freq(struct net_device *dev,
 	return rc;
 }
 
+/*
+ * This function intends to handle the Get Freq command.
+ * Currently, the request comes via the Wireless Extensions' SIOCGIWFREQ ioctl.
+ *
+ */
 static int r8711_wx_get_freq(struct net_device *dev,
 			     struct iw_request_info *info,
 			     union iwreq_data *wrqu, char *extra)
@@ -736,11 +746,21 @@ static int r8711_wx_get_freq(struct net_device *dev,
 			       pcur_bss->Configuration.DSConfig-1] * 100000;
 		wrqu->freq.e = 1;
 		wrqu->freq.i = pcur_bss->Configuration.DSConfig;
-	} else
-		return -1;
+	} else {
+		return -ENOLINK;
+	}
 	return 0;
 }
 
+/*
+ * This function intends to handle the Set Mode command.
+ * Currently, the request comes via the Wireless Extensions' SIOCSIWMODE ioctl.
+ *
+ * Note: Currently (July 2011) the call to
+ * r8712_set_802_11_infrastructure_mode() always returns true. Since we have no
+ * specific failure reason, we return EPERM in lieu of general failure.
+ *
+ */
 static int r8711_wx_set_mode(struct net_device *dev,
 			     struct iw_request_info *a,
 			     union iwreq_data *wrqu, char *b)
@@ -769,10 +789,15 @@ static int r8711_wx_set_mode(struct net_device *dev,
 	else
 		r8712_setopmode_cmd(padapter, Ndis802_11AutoUnknown);
 	if (!r8712_set_802_11_infrastructure_mode(padapter, networkType))
-		return -1;
+		return -EPERM; /* Unknown failure. */
 	return 0;
 }
 
+/*
+ * This function intends to handle the Get Mode command.
+ * Currently, the request comes via the Wireless Extensions' SIOCGIWMODE ioctl.
+ *
+ */
 static int r8711_wx_get_mode(struct net_device *dev, struct iw_request_info *a,
 			     union iwreq_data *wrqu, char *b)
 {
@@ -975,6 +1000,16 @@ static int r871x_wx_set_priv(struct net_device *dev,
  * s2. set_802_11_authentication_mode()
  * s3. set_802_11_encryption_mode()
  * s4. set_802_11_bssid()
+ *
+ * This function intends to handle the Set AP command, which specifies the
+ * MAC# of a preferred Access Point.
+ * Currently, the request comes via Wireless Extensions' SIOCSIWAP ioctl.
+ *
+ * For this operation to succeed, there is no need for the interface to be Up.
+ *
+ * Note: Currently (July 2011) r8712_set_802_11_bssid() may fail for one of
+ * several reasons. For now, we let -1 be returned as a catch-all failure
+ * indication, until that function's implementation is updated. 
  */
 static int r8711_wx_set_wap(struct net_device *dev,
 			 struct iw_request_info *info,
@@ -995,7 +1030,7 @@ static int r8711_wx_set_wap(struct net_device *dev,
 	if (padapter->bup == false)
 		return -1;
 	if (check_fwstate(pmlmepriv, _FW_UNDER_SURVEY) == true)
-		return -1;
+		return -EBUSY;
 	if (check_fwstate(pmlmepriv, _FW_UNDER_LINKING) == true)
 		return ret;
 	if (temp->sa_family != ARPHRD_ETHER)
@@ -1014,14 +1049,14 @@ static int r8711_wx_set_wap(struct net_device *dev,
 		if (!memcmp(dst_bssid, temp->sa_data, ETH_ALEN)) {
 			if (r8712_set_802_11_infrastructure_mode(padapter,
 			    pnetwork->network.InfrastructureMode) == false)
-				ret = -1;
+				ret = -EPERM; /* Unknown failure. */
 			break;
 		}
 	}
 	spin_unlock_irqrestore(&queue->lock, irqL);
 	if (!ret) {
 		if (!r8712_set_802_11_authentication_mode(padapter, authmode))
-			ret = -1;
+			ret = -ENOMEM;
 		else {
 			if (!r8712_set_802_11_bssid(padapter, temp->sa_data))
 				ret = -1;
@@ -1074,6 +1109,19 @@ static int r871x_wx_set_mlme(struct net_device *dev,
 	return ret;
 }
 
+/**
+ *
+ * This function intends to handle the Set Scan command.
+ * Currently, the request comes via Wireless Extensions' SIOCSIWSCAN ioctl.
+ *
+ * For this operation to succeed, the interface is brought Up beforehand.
+ *
+ * Note: It is not clear what value we ought to return when hw_init_completed
+ * is false. If the firmware could not be found/loaded, which errno should we
+ * return?
+ * The same question arises for bDriverStopped being true.
+ *
+ */ 
 static int r8711_wx_set_scan(struct net_device *dev,
 			struct iw_request_info *a,
 			union iwreq_data *wrqu, char *extra)
@@ -1088,7 +1136,7 @@ static int r8711_wx_set_scan(struct net_device *dev,
 		return -1;
 	}
 	if (padapter->bup == false)
-		return -1;
+		return -ENETDOWN;
 	if (padapter->hw_init_completed == false)
 		return -1;
 	if ((check_fwstate(pmlmepriv, _FW_UNDER_SURVEY|_FW_UNDER_LINKING)) ||
@@ -1122,6 +1170,13 @@ static int r8711_wx_set_scan(struct net_device *dev,
 	return 0;
 }
 
+/**
+ *
+ * This function intends to handle the Get Scan command.
+ * Currently, the request comes via Wireless Extensions' SIOCGIWSCAN ioctl.
+ *
+ *
+ */
 static int r8711_wx_get_scan(struct net_device *dev,
 				struct iw_request_info *a,
 				union iwreq_data *wrqu, char *extra)
@@ -1169,6 +1224,16 @@ static int r8711_wx_get_scan(struct net_device *dev,
  * s2. set_802_11_authenticaion_mode()
  * s3. set_802_11_encryption_mode()
  * s4. set_802_11_ssid()
+ *
+ * This function intends to handle the Set ESSID command.
+ * Currently, the request comes via the Wireless Extensions' SIOCSIWESSID ioctl.
+ *
+ * For this operation to succeed, there is no need for the interface to be Up.
+ *
+ * Note: Currently (July 2011) the call to
+ * r8712_set_802_11_infrastructure_mode() always returns true. Since we have no
+ * specific failure reason, we return EPERM in lieu of general failure.
+ *
  */
 static int r8711_wx_set_essid(struct net_device *dev,
 				struct iw_request_info *a,
@@ -1187,7 +1252,7 @@ static int r8711_wx_set_essid(struct net_device *dev,
 	if (padapter->bup == false)
 		return -1;
 	if (check_fwstate(pmlmepriv, _FW_UNDER_SURVEY))
-		return -1;
+		return -EBUSY;
 	if (check_fwstate(pmlmepriv, _FW_UNDER_LINKING))
 		return 0;
 	if (wrqu->essid.length > IW_ESSID_MAX_SIZE)
@@ -1215,7 +1280,7 @@ static int r8711_wx_set_essid(struct net_device *dev,
 				if (!r8712_set_802_11_infrastructure_mode(
 				     padapter,
 				     pnetwork->network.InfrastructureMode))
-					return -1;
+					return -EPERM; /* Unknown failure. */
 				break;
 			}
 		}
@@ -1225,6 +1290,12 @@ static int r8711_wx_set_essid(struct net_device *dev,
 	return -EINPROGRESS;
 }
 
+/**
+ *
+ * This function intends to handle the Get ESSID command.
+ * Currently, the request comes via Wireless Extensions' SIOCGIWESSID ioctl.
+ *
+ */
 static int r8711_wx_get_essid(struct net_device *dev,
 				struct iw_request_info *a,
 				union iwreq_data *wrqu, char *extra)
@@ -1240,10 +1311,16 @@ static int r8711_wx_get_essid(struct net_device *dev,
 		memcpy(extra, pcur_bss->Ssid.Ssid, len);
 		wrqu->essid.flags = 1;
 	} else
-		ret = -1;
+		ret = -ENOLINK;
 	return ret;
 }
 
+/**
+ *
+ * This function intends to handle the Set Rate command.
+ * Currently, the request comes via the Wireless Extensions' SIOCSIWRATE ioctl.
+ *
+ */
 static int r8711_wx_set_rate(struct net_device *dev,
 				struct iw_request_info *a,
 				union iwreq_data *wrqu, char *extra)
@@ -1312,10 +1389,16 @@ set_rate:
 			datarates[i] = 0xff;
 	}
 	if (r8712_setdatarate_cmd(padapter, datarates) != _SUCCESS)
-		ret = -1;
+		ret = -ENOMEM;
 	return ret;
 }
 
+/**
+ *
+ * This function intends to handle the Get Rate command.
+ * Currently, the request comes via the Wireless Extensions' SIOCGIWRATE ioctl.
+ *
+ */
 static int r8711_wx_get_rate(struct net_device *dev,
 			     struct iw_request_info *info,
 			     union iwreq_data *wrqu, char *extra)
@@ -1371,10 +1454,16 @@ static int r8711_wx_get_rate(struct net_device *dev,
 			wrqu->bitrate.value = max_rate * 500000;
 		}
 	} else
-		return -1;
+		return -ENOLINK;
 	return 0;
 }
 
+/**
+ *
+ * This function intends to handle the Get RTS Threshold command.
+ * Currently, the request comes via the Wireless Extensions' SIOCGIWRTS ioctl.
+ *
+ */
 static int r8711_wx_get_rts(struct net_device *dev,
 				struct iw_request_info *info,
 				union iwreq_data *wrqu, char *extra)
@@ -1701,7 +1790,7 @@ static int r871x_wx_set_enc_ext(struct net_device *dev,
 	param_len = sizeof(struct ieee_param) + pext->key_len;
 	param = (struct ieee_param *)_malloc(param_len);
 	if (param == NULL)
-		return -1;
+		return -ENOMEM;
 	memset(param, 0, param_len);
 	param->cmd = IEEE_CMD_SET_ENCRYPTION;
 	memset(param->sta_addr, 0xff, ETH_ALEN);
@@ -1719,7 +1808,7 @@ static int r871x_wx_set_enc_ext(struct net_device *dev,
 		alg_name = "CCMP";
 		break;
 	default:
-		return -1;
+		return -EINVAL;
 	}
 	strncpy((char *)param->u.crypt.alg, alg_name, IEEE_CRYPT_ALG_NAME_LEN);
 	if (pext->ext_flags & IW_ENCODE_EXT_GROUP_KEY)
@@ -1785,7 +1874,7 @@ static int dummy(struct net_device *dev,
 		struct iw_request_info *a,
 		union iwreq_data *wrqu, char *b)
 {
-	return -1;
+	return -ENOSYS;
 }
 
 static int r8711_drvext_hdl(struct net_device *dev,
-- 
1.7.6