staging: rtl8712: Use completions for signaling

r8712_sitesurvey_cmd() uses a variable to notify r8712_SetFilter() that it
has completed operation. There is no sort of assurance that the variable will
actually change and it could cache the value the first time it is read and
then never update it for the whole loop logic.

Use completion variables because they are better suited for the purpose.

This patch fixes the checkpatch.pl warnings like:
CHECK: Avoid CamelCase: <blnEnableRxFF0Filter>
+ u8 blnEnableRxFF0Filter;

Reviewed-by: Fabio M. De Francesco <[e-mail]>
Signed-off-by: Sathish Kumar <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Greg Kroah-Hartman <[e-mail]>

drivers/staging/rtl8712/drv_types.h

···
 	struct iw_statistics iwstats;
 	int pid; /*process id from UI*/
 	struct work_struct wk_filter_rx_ff0;
-	u8 blnEnableRxFF0Filter;
-	spinlock_t lock_rx_ff0_filter;
 	const struct firmware *fw;
 	struct usb_interface *pusb_intf;
 	struct mutex mutex_start;
 	struct completion rtl8712_fw_ready;
+	struct completion rx_filter_ready;
 };
 
 static inline u8 *myid(struct eeprom_priv *peepriv)

drivers/staging/rtl8712/rtl871x_cmd.c

···
 	mod_timer(&pmlmepriv->scan_to_timer,
 		  jiffies + msecs_to_jiffies(SCANNING_TIMEOUT));
 	padapter->ledpriv.LedControlHandler(padapter, LED_CTL_SITE_SURVEY);
-	padapter->blnEnableRxFF0Filter = 0;
+	complete(&padapter->rx_filter_ready);
 	return _SUCCESS;
 }
 

drivers/staging/rtl8712/usb_intf.c

···
 	/* step 6. Load the firmware asynchronously */
 	if (rtl871x_load_fw(padapter))
 		goto deinit_drv_sw;
-	spin_lock_init(&padapter->lock_rx_ff0_filter);
+	init_completion(&padapter->rx_filter_ready);
 	mutex_init(&padapter->mutex_start);
 	return 0;
 

drivers/staging/rtl8712/xmit_linux.c

···
 	struct _adapter *adapter = container_of(work, struct _adapter,
 						wk_filter_rx_ff0);
 	u8  oldvalue = 0x00, newvalue = 0x00;
-	unsigned long irqL;
 
 	oldvalue = r8712_read8(adapter, 0x117);
 	newvalue = oldvalue & 0xfe;
 	r8712_write8(adapter, 0x117, newvalue);
 
-	spin_lock_irqsave(&adapter->lock_rx_ff0_filter, irqL);
-	adapter->blnEnableRxFF0Filter = 1;
-	spin_unlock_irqrestore(&adapter->lock_rx_ff0_filter, irqL);
-	do {
-		msleep(100);
-	} while (adapter->blnEnableRxFF0Filter == 1);
+	wait_for_completion(&adapter->rx_filter_ready);
 	r8712_write8(adapter, 0x117, oldvalue);
 }