Staging: winbond: Check for unsuccessful allocation immediately

Check to see if allocation by kzalloc() or usb_alloc_urb() was unsuccessful
immediately after the allocation. Exit from the function can be right at that
point in case of allocation failure.
This avoids unnecessary use of usb_alloc_urb() & usb_free_urb() if kzalloc()
returns NULL.
Also, makes the code better structured & easier to understand.
Signed-off-by: Harsh Kumar <harsh1kumar@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/winbond/wb35reg.c

@@ -30,8 +30,15 @@ unsigned char Wb35Reg_BurstWrite(struct hw_data *pHwData, u16 RegisterNo, u32 *p
 	/* Trying to use burst write function if use new hardware */
 	UrbSize = sizeof(struct wb35_reg_queue) + DataSize + sizeof(struct usb_ctrlrequest);
 	reg_queue = kzalloc(UrbSize, GFP_ATOMIC);
+	if (reg_queue == NULL)
+		return false;
+
 	urb = usb_alloc_urb(0, GFP_ATOMIC);
-	if (urb && reg_queue) {
+	if (urb == NULL) {
+		kfree(reg_queue);
+		return false;
+	}
+
 	reg_queue->DIRECT = 2; /* burst write register */
 	reg_queue->INDEX = RegisterNo;
 	reg_queue->pBuffer = (u32 *)((u8 *)reg_queue + sizeof(struct wb35_reg_queue));
@@ -63,12 +70,6 @@ unsigned char Wb35Reg_BurstWrite(struct hw_data *pHwData, u16 RegisterNo, u32 *p
 	Wb35Reg_EP0VM_start(pHwData);
 
 	return true;
-	} else {
-		usb_free_urb(urb);
-		kfree(reg_queue);
-		return false;
-	}
-	return false;
 }
 
 void Wb35Reg_Update(struct hw_data *pHwData,  u16 RegisterNo,  u32 RegisterValue)
@@ -173,8 +174,15 @@ unsigned char Wb35Reg_Write(struct hw_data *pHwData, u16 RegisterNo, u32 Registe
 	/* update the register by send urb request */
 	UrbSize = sizeof(struct wb35_reg_queue) + sizeof(struct usb_ctrlrequest);
 	reg_queue = kzalloc(UrbSize, GFP_ATOMIC);
+	if (reg_queue == NULL)
+		return false;
+
 	urb = usb_alloc_urb(0, GFP_ATOMIC);
-	if (urb && reg_queue) {
+	if (urb == NULL) {
+		kfree(reg_queue);
+		return false;
+	}
+
 	reg_queue->DIRECT = 1; /* burst write register */
 	reg_queue->INDEX = RegisterNo;
 	reg_queue->VALUE = cpu_to_le32(RegisterValue);
@@ -204,11 +212,6 @@ unsigned char Wb35Reg_Write(struct hw_data *pHwData, u16 RegisterNo, u32 Registe
 	Wb35Reg_EP0VM_start(pHwData);
 
 	return true;
-	} else {
-		usb_free_urb(urb);
-		kfree(reg_queue);
-		return false;
-	}
 }
 
 /*
@@ -236,8 +239,15 @@ unsigned char Wb35Reg_WriteWithCallbackValue(struct hw_data *pHwData,
 	/* update the register by send urb request */
 	UrbSize = sizeof(struct wb35_reg_queue) + sizeof(struct usb_ctrlrequest);
 	reg_queue = kzalloc(UrbSize, GFP_ATOMIC);
+	if (reg_queue == NULL)
+		return false;
+
 	urb = usb_alloc_urb(0, GFP_ATOMIC);
-	if (urb && reg_queue) {
+	if (urb == NULL) {
+		kfree(reg_queue);
+		return false;
+	}
+
 	reg_queue->DIRECT = 1; /* burst write register */
 	reg_queue->INDEX = RegisterNo;
 	reg_queue->VALUE = cpu_to_le32(RegisterValue);
@@ -266,12 +276,8 @@ unsigned char Wb35Reg_WriteWithCallbackValue(struct hw_data *pHwData,
 
 	/* Start EP0VM */
 	Wb35Reg_EP0VM_start(pHwData);
+
 	return true;
-	} else {
-		usb_free_urb(urb);
-		kfree(reg_queue);
-		return false;
-	}
 }
 
 /*
@@ -341,8 +347,14 @@ unsigned char Wb35Reg_Read(struct hw_data *pHwData, u16 RegisterNo, u32 *pRegist
 	/* update the variable by send Urb to read register */
 	UrbSize = sizeof(struct wb35_reg_queue) + sizeof(struct usb_ctrlrequest);
 	reg_queue = kzalloc(UrbSize, GFP_ATOMIC);
+	if (reg_queue == NULL)
+		return false;
+
 	urb = usb_alloc_urb(0, GFP_ATOMIC);
-	if (urb && reg_queue) {
+	if (urb == NULL) {
+		kfree(reg_queue);
+		return false;
+	}
 	reg_queue->DIRECT = 0; /* read register */
 	reg_queue->INDEX = RegisterNo;
 	reg_queue->pBuffer = pRegisterValue;
@@ -370,11 +382,6 @@ unsigned char Wb35Reg_Read(struct hw_data *pHwData, u16 RegisterNo, u32 *pRegist
 	Wb35Reg_EP0VM_start(pHwData);
 
 	return true;
-	} else {
-		usb_free_urb(urb);
-		kfree(reg_queue);
-		return false;
-	}
 }