rtw88: decompose while(1) loop of power sequence polling command

The power polling command is one kind of power sequence commands. It's used
to check hardware situation, and subsequent comamnds will be executed if
hardware is ready. A special case is PCIE must toggle BIT_PFM_WOWL and try
again if first try is failed.

In order to reduce indentation to understand the code easier, move polling
part to a separate function. Then, the 'while (1)...loop' is replaced by
two statements to do first try and retry.
Signed-off-by: Ping-Ke Shih <pkshih@realtek.com>
Signed-off-by: Yan-Hsuan Chuang <yhchuang@realtek.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20200422034607.28747-5-yhchuang@realtek.com

drivers/net/wireless/realtek/rtw88/mac.c

@@ -108,51 +108,55 @@ static int rtw_mac_pre_system_cfg(struct rtw_dev *rtwdev)
 	return 0;
 }
 
+static bool do_pwr_poll_cmd(struct rtw_dev *rtwdev, u32 addr, u32 mask, u32 target)
+{
+	u32 cnt;
+
+	target &= mask;
+
+	for (cnt = 0; cnt < RTW_PWR_POLLING_CNT; cnt++) {
+		if ((rtw_read8(rtwdev, addr) & mask) == target)
+			return true;
+
+		udelay(50);
+	}
+
+	return false;
+}
+
 static int rtw_pwr_cmd_polling(struct rtw_dev *rtwdev,
 			       const struct rtw_pwr_seq_cmd *cmd)
 {
 	u8 value;
-	u8 flag = 0;
 	u32 offset;
-	u32 cnt = RTW_PWR_POLLING_CNT;
 
 	if (cmd->base == RTW_PWR_ADDR_SDIO)
 		offset = cmd->offset | SDIO_LOCAL_OFFSET;
 	else
 		offset = cmd->offset;
 
-	do {
-		cnt--;
-		value = rtw_read8(rtwdev, offset);
-		value &= cmd->mask;
-		if (value == (cmd->value & cmd->mask))
-			return 0;
-		if (cnt == 0) {
-			if (rtw_hci_type(rtwdev) == RTW_HCI_TYPE_PCIE &&
-			    flag == 0) {
-				value = rtw_read8(rtwdev, REG_SYS_PW_CTRL);
-				if (rtwdev->chip->id == RTW_CHIP_TYPE_8723D) {
-					value &= ~BIT_PFM_WOWL;
-					rtw_write8(rtwdev, REG_SYS_PW_CTRL, value);
-				}
-				value |= BIT_PFM_WOWL;
-				rtw_write8(rtwdev, REG_SYS_PW_CTRL, value);
-				value &= ~BIT_PFM_WOWL;
-				rtw_write8(rtwdev, REG_SYS_PW_CTRL, value);
-				if (rtwdev->chip->id == RTW_CHIP_TYPE_8723D) {
-					value |= BIT_PFM_WOWL;
-					rtw_write8(rtwdev, REG_SYS_PW_CTRL, value);
-				}
-
-				cnt = RTW_PWR_POLLING_CNT;
-				flag = 1;
-			} else {
-				return -EBUSY;
-			}
-		} else {
-			udelay(50);
-		}
-	} while (1);
+	if (do_pwr_poll_cmd(rtwdev, offset, cmd->mask, cmd->value))
+		return 0;
+
+	if (rtw_hci_type(rtwdev) != RTW_HCI_TYPE_PCIE)
+		goto err;
+
+	/* if PCIE, toggle BIT_PFM_WOWL and try again */
+	value = rtw_read8(rtwdev, REG_SYS_PW_CTRL);
+	if (rtwdev->chip->id == RTW_CHIP_TYPE_8723D)
+		rtw_write8(rtwdev, REG_SYS_PW_CTRL, value & ~BIT_PFM_WOWL);
+	rtw_write8(rtwdev, REG_SYS_PW_CTRL, value | BIT_PFM_WOWL);
+	rtw_write8(rtwdev, REG_SYS_PW_CTRL, value & ~BIT_PFM_WOWL);
+	if (rtwdev->chip->id == RTW_CHIP_TYPE_8723D)
+		rtw_write8(rtwdev, REG_SYS_PW_CTRL, value | BIT_PFM_WOWL);
+
+	if (do_pwr_poll_cmd(rtwdev, offset, cmd->mask, cmd->value))
+		return 0;
+
+err:
+	rtw_err(rtwdev, "failed to poll offset=0x%x mask=0x%x value=0x%x\n",
+		offset, cmd->mask, cmd->value);
+	return -EBUSY;
 }
 
 static int rtw_sub_pwr_seq_parser(struct rtw_dev *rtwdev, u8 intf_mask,