[1/2] wifi: mwifiex: simplify PCIE write operations

Commit Message

Dmitry Antipov Sept. 19, 2023, 1:27 p.m. UTC

Since 'mwifiex_write_reg()' just issues void 'iowrite32()',
convert the former to 'void' and simplify all related users
(with the only exception of 'read_poll_timeout()' which
explicitly requires a non-void function argument).

Found by Linux Verification Center (linuxtesting.org) with SVACE.

Signed-off-by: Dmitry Antipov <[e-mail]>
---
 drivers/net/wireless/marvell/mwifiex/pcie.c | 290 +++++---------------
 1 file changed, 66 insertions(+), 224 deletions(-)

Comments

Brian Norris Sept. 20, 2023, 11:31 p.m. UTC | #1

On Tue, Sep 19, 2023 at 04:27:59PM +0300, Dmitry Antipov wrote:
> Since 'mwifiex_write_reg()' just issues void 'iowrite32()',
> convert the former to 'void' and simplify all related users
> (with the only exception of 'read_poll_timeout()' which
> explicitly requires a non-void function argument).
> 
> Found by Linux Verification Center (linuxtesting.org) with SVACE.
> 
> Signed-off-by: Dmitry Antipov <[e-mail]>
> ---
>  drivers/net/wireless/marvell/mwifiex/pcie.c | 290 +++++---------------
>  1 file changed, 66 insertions(+), 224 deletions(-)

Acked-by: Brian Norris <[e-mail]>

> diff --git a/drivers/net/wireless/marvell/mwifiex/pcie.c b/drivers/net/wireless/marvell/mwifiex/pcie.c
> index 6697132ecc97..88f632b9dd93 100644
> --- a/drivers/net/wireless/marvell/mwifiex/pcie.c
> +++ b/drivers/net/wireless/marvell/mwifiex/pcie.c
...  
> +/* Non-void wrapper needed for read_poll_timeout(). */
> +static inline int
> +mwifiex_write_reg_rpt(struct mwifiex_adapter *adapter, int reg, u32 data)

This is kind of a weird name, but I don't have better suggestions. Maybe
it helps dissuade people from using it outside its very specific context
(where you have to read the comment to understand what "rpt" means).

Kalle Valo Sept. 22, 2023, 7:43 a.m. UTC | #2

Dmitry Antipov <[e-mail]> wrote:

> Since 'mwifiex_write_reg()' just issues void 'iowrite32()',
> convert the former to 'void' and simplify all related users
> (with the only exception of 'read_poll_timeout()' which
> explicitly requires a non-void function argument).
> 
> Found by Linux Verification Center (linuxtesting.org) with SVACE.
> 
> Signed-off-by: Dmitry Antipov <[e-mail]>
> Acked-by: Brian Norris <[e-mail]>

2 patches applied to wireless-next.git, thanks.

c2e01a3a7b9a wifi: mwifiex: simplify PCIE write operations
804edf4d18e2 wifi: mwifiex: followup PCIE and related cleanups

Patch

diff --git a/drivers/net/wireless/marvell/mwifiex/pcie.c b/drivers/net/wireless/marvell/mwifiex/pcie.c
index 6697132ecc97..88f632b9dd93 100644
--- a/drivers/net/wireless/marvell/mwifiex/pcie.c
+++ b/drivers/net/wireless/marvell/mwifiex/pcie.c
@@ -222,12 +222,19 @@  static void mwifiex_unmap_pci_memory(struct mwifiex_adapter *adapter,
 /*
  * This function writes data into PCIE card register.
  */
-static int mwifiex_write_reg(struct mwifiex_adapter *adapter, int reg, u32 data)
+static inline void
+mwifiex_write_reg(struct mwifiex_adapter *adapter, int reg, u32 data)
 {
 	struct pcie_service_card *card = adapter->card;
 
 	iowrite32(data, card->pci_mmap1 + reg);
+}
 
+/* Non-void wrapper needed for read_poll_timeout(). */
+static inline int
+mwifiex_write_reg_rpt(struct mwifiex_adapter *adapter, int reg, u32 data)
+{
+	mwifiex_write_reg(adapter, reg, data);
 	return 0;
 }
 
@@ -658,12 +665,12 @@  static int mwifiex_pm_wakeup_card(struct mwifiex_adapter *adapter)
 	 * appears to ignore or miss our wakeup request, so we continue trying
 	 * until we receive an interrupt from the card.
 	 */
-	if (read_poll_timeout(mwifiex_write_reg, retval,
+	if (read_poll_timeout(mwifiex_write_reg_rpt, retval,
 			      READ_ONCE(adapter->int_status) != 0,
 			      500, 500 * N_WAKEUP_TRIES_SHORT_INTERVAL,
 			      false,
 			      adapter, reg->fw_status, FIRMWARE_READY_PCIE)) {
-		if (read_poll_timeout(mwifiex_write_reg, retval,
+		if (read_poll_timeout(mwifiex_write_reg_rpt, retval,
 				      READ_ONCE(adapter->int_status) != 0,
 				      10000, 10000 * N_WAKEUP_TRIES_LONG_INTERVAL,
 				      false,
@@ -705,14 +712,8 @@  static int mwifiex_pm_wakeup_card_complete(struct mwifiex_adapter *adapter)
  */
 static int mwifiex_pcie_disable_host_int(struct mwifiex_adapter *adapter)
 {
-	if (mwifiex_pcie_ok_to_access_hw(adapter)) {
-		if (mwifiex_write_reg(adapter, PCIE_HOST_INT_MASK,
-				      0x00000000)) {
-			mwifiex_dbg(adapter, ERROR,
-				    "Disable host interrupt failed\n");
-			return -1;
-		}
-	}
+	if (mwifiex_pcie_ok_to_access_hw(adapter))
+		mwifiex_write_reg(adapter, PCIE_HOST_INT_MASK, 0x00000000);
 
 	atomic_set(&adapter->tx_hw_pending, 0);
 	return 0;
@@ -731,15 +732,9 @@  static void mwifiex_pcie_disable_host_int_noerr(struct mwifiex_adapter *adapter)
  */
 static int mwifiex_pcie_enable_host_int(struct mwifiex_adapter *adapter)
 {
-	if (mwifiex_pcie_ok_to_access_hw(adapter)) {
+	if (mwifiex_pcie_ok_to_access_hw(adapter))
 		/* Simply write the mask to the register */
-		if (mwifiex_write_reg(adapter, PCIE_HOST_INT_MASK,
-				      HOST_INTR_MASK)) {
-			mwifiex_dbg(adapter, ERROR,
-				    "Enable host interrupt failed\n");
-			return -1;
-		}
-	}
+		mwifiex_write_reg(adapter, PCIE_HOST_INT_MASK, HOST_INTR_MASK);
 
 	return 0;
 }
@@ -1312,12 +1307,8 @@  static int mwifiex_clean_pcie_ring_buf(struct mwifiex_adapter *adapter)
 		/* write pointer already set at last send
 		 * send dnld-rdy intr again, wait for completion.
 		 */
-		if (mwifiex_write_reg(adapter, PCIE_CPU_INT_EVENT,
-				      CPU_INTR_DNLD_RDY)) {
-			mwifiex_dbg(adapter, ERROR,
-				    "failed to assert dnld-rdy interrupt.\n");
-			return -1;
-		}
+		mwifiex_write_reg(adapter, PCIE_CPU_INT_EVENT,
+				  CPU_INTR_DNLD_RDY);
 	}
 	return 0;
 }
@@ -1429,7 +1420,6 @@  mwifiex_pcie_send_data(struct mwifiex_adapter *adapter, struct sk_buff *skb,
 	struct pcie_service_card *card = adapter->card;
 	const struct mwifiex_pcie_card_reg *reg = card->pcie.reg;
 	u32 wrindx, num_tx_buffs, rx_val;
-	int ret;
 	dma_addr_t buf_pa;
 	struct mwifiex_pcie_buf_desc *desc = NULL;
 	struct mwifiex_pfu_buf_desc *desc2 = NULL;
@@ -1498,13 +1488,8 @@  mwifiex_pcie_send_data(struct mwifiex_adapter *adapter, struct sk_buff *skb,
 
 		rx_val = card->rxbd_rdptr & reg->rx_wrap_mask;
 		/* Write the TX ring write pointer in to reg->tx_wrptr */
-		if (mwifiex_write_reg(adapter, reg->tx_wrptr,
-				      card->txbd_wrptr | rx_val)) {
-			mwifiex_dbg(adapter, ERROR,
-				    "SEND DATA: failed to write reg->tx_wrptr\n");
-			ret = -1;
-			goto done_unmap;
-		}
+		mwifiex_write_reg(adapter, reg->tx_wrptr,
+				  card->txbd_wrptr | rx_val);
 
 		/* The firmware (latest version 15.68.19.p21) of the 88W8897 PCIe+USB card
 		 * seems to crash randomly after setting the TX ring write pointer when
@@ -1521,13 +1506,8 @@  mwifiex_pcie_send_data(struct mwifiex_adapter *adapter, struct sk_buff *skb,
 			adapter->data_sent = false;
 		} else {
 			/* Send the TX ready interrupt */
-			if (mwifiex_write_reg(adapter, PCIE_CPU_INT_EVENT,
-					      CPU_INTR_DNLD_RDY)) {
-				mwifiex_dbg(adapter, ERROR,
-					    "SEND DATA: failed to assert dnld-rdy interrupt.\n");
-				ret = -1;
-				goto done_unmap;
-			}
+			mwifiex_write_reg(adapter, PCIE_CPU_INT_EVENT,
+					  CPU_INTR_DNLD_RDY);
 		}
 		mwifiex_dbg(adapter, DATA,
 			    "info: SEND DATA: Updated <Rd: %#x, Wr:\t"
@@ -1538,24 +1518,12 @@  mwifiex_pcie_send_data(struct mwifiex_adapter *adapter, struct sk_buff *skb,
 			    "info: TX Ring full, can't send packets to fw\n");
 		adapter->data_sent = true;
 		/* Send the TX ready interrupt */
-		if (mwifiex_write_reg(adapter, PCIE_CPU_INT_EVENT,
-				      CPU_INTR_DNLD_RDY))
-			mwifiex_dbg(adapter, ERROR,
-				    "SEND DATA: failed to assert door-bell intr\n");
+		mwifiex_write_reg(adapter, PCIE_CPU_INT_EVENT,
+				  CPU_INTR_DNLD_RDY);
 		return -EBUSY;
 	}
 
 	return -EINPROGRESS;
-done_unmap:
-	mwifiex_unmap_pci_memory(adapter, skb, DMA_TO_DEVICE);
-	card->tx_buf_list[wrindx] = NULL;
-	atomic_dec(&adapter->tx_hw_pending);
-	if (reg->pfu_enabled)
-		memset(desc2, 0, sizeof(*desc2));
-	else
-		memset(desc, 0, sizeof(*desc));
-
-	return ret;
 }
 
 /*
@@ -1675,13 +1643,8 @@  static int mwifiex_pcie_process_recv_data(struct mwifiex_adapter *adapter)
 
 		tx_val = card->txbd_wrptr & reg->tx_wrap_mask;
 		/* Write the RX ring read pointer in to reg->rx_rdptr */
-		if (mwifiex_write_reg(adapter, reg->rx_rdptr,
-				      card->rxbd_rdptr | tx_val)) {
-			mwifiex_dbg(adapter, DATA,
-				    "RECV DATA: failed to write reg->rx_rdptr\n");
-			ret = -1;
-			goto done;
-		}
+		mwifiex_write_reg(adapter, reg->rx_rdptr,
+				  card->rxbd_rdptr | tx_val);
 
 		/* Read the RX ring Write pointer set by firmware */
 		if (mwifiex_read_reg(adapter, reg->rx_wrptr, &wrptr)) {
@@ -1724,43 +1687,18 @@  mwifiex_pcie_send_boot_cmd(struct mwifiex_adapter *adapter, struct sk_buff *skb)
 	/* Write the lower 32bits of the physical address to low command
 	 * address scratch register
 	 */
-	if (mwifiex_write_reg(adapter, reg->cmd_addr_lo, (u32)buf_pa)) {
-		mwifiex_dbg(adapter, ERROR,
-			    "%s: failed to write download command to boot code.\n",
-			    __func__);
-		mwifiex_unmap_pci_memory(adapter, skb, DMA_TO_DEVICE);
-		return -1;
-	}
+	mwifiex_write_reg(adapter, reg->cmd_addr_lo, (u32)buf_pa);
 
 	/* Write the upper 32bits of the physical address to high command
 	 * address scratch register
 	 */
-	if (mwifiex_write_reg(adapter, reg->cmd_addr_hi,
-			      (u32)((u64)buf_pa >> 32))) {
-		mwifiex_dbg(adapter, ERROR,
-			    "%s: failed to write download command to boot code.\n",
-			    __func__);
-		mwifiex_unmap_pci_memory(adapter, skb, DMA_TO_DEVICE);
-		return -1;
-	}
+	mwifiex_write_reg(adapter, reg->cmd_addr_hi, (u32)((u64)buf_pa >> 32));
 
 	/* Write the command length to cmd_size scratch register */
-	if (mwifiex_write_reg(adapter, reg->cmd_size, skb->len)) {
-		mwifiex_dbg(adapter, ERROR,
-			    "%s: failed to write command len to cmd_size scratch reg\n",
-			    __func__);
-		mwifiex_unmap_pci_memory(adapter, skb, DMA_TO_DEVICE);
-		return -1;
-	}
+	mwifiex_write_reg(adapter, reg->cmd_size, skb->len);
 
 	/* Ring the door bell */
-	if (mwifiex_write_reg(adapter, PCIE_CPU_INT_EVENT,
-			      CPU_INTR_DOOR_BELL)) {
-		mwifiex_dbg(adapter, ERROR,
-			    "%s: failed to assert door-bell intr\n", __func__);
-		mwifiex_unmap_pci_memory(adapter, skb, DMA_TO_DEVICE);
-		return -1;
-	}
+	mwifiex_write_reg(adapter, PCIE_CPU_INT_EVENT, CPU_INTR_DOOR_BELL);
 
 	return 0;
 }
@@ -1775,12 +1713,8 @@  static int mwifiex_pcie_init_fw_port(struct mwifiex_adapter *adapter)
 	int tx_wrap = card->txbd_wrptr & reg->tx_wrap_mask;
 
 	/* Write the RX ring read pointer in to reg->rx_rdptr */
-	if (mwifiex_write_reg(adapter, reg->rx_rdptr, card->rxbd_rdptr |
-			      tx_wrap)) {
-		mwifiex_dbg(adapter, ERROR,
-			    "RECV DATA: failed to write reg->rx_rdptr\n");
-		return -1;
-	}
+	mwifiex_write_reg(adapter, reg->rx_rdptr, card->rxbd_rdptr | tx_wrap);
+
 	return 0;
 }
 
@@ -1791,7 +1725,6 @@  mwifiex_pcie_send_cmd(struct mwifiex_adapter *adapter, struct sk_buff *skb)
 {
 	struct pcie_service_card *card = adapter->card;
 	const struct mwifiex_pcie_card_reg *reg = card->pcie.reg;
-	int ret = 0;
 	dma_addr_t cmd_buf_pa, cmdrsp_buf_pa;
 	u8 *payload = (u8 *)skb->data;
 
@@ -1841,63 +1774,29 @@  mwifiex_pcie_send_cmd(struct mwifiex_adapter *adapter, struct sk_buff *skb)
 		cmdrsp_buf_pa = MWIFIEX_SKB_DMA_ADDR(card->cmdrsp_buf);
 		/* Write the lower 32bits of the cmdrsp buffer physical
 		   address */
-		if (mwifiex_write_reg(adapter, reg->cmdrsp_addr_lo,
-				      (u32)cmdrsp_buf_pa)) {
-			mwifiex_dbg(adapter, ERROR,
-				    "Failed to write download cmd to boot code.\n");
-			ret = -1;
-			goto done;
-		}
+		mwifiex_write_reg(adapter, reg->cmdrsp_addr_lo,
+				  (u32)cmdrsp_buf_pa);
+
 		/* Write the upper 32bits of the cmdrsp buffer physical
 		   address */
-		if (mwifiex_write_reg(adapter, reg->cmdrsp_addr_hi,
-				      (u32)((u64)cmdrsp_buf_pa >> 32))) {
-			mwifiex_dbg(adapter, ERROR,
-				    "Failed to write download cmd to boot code.\n");
-			ret = -1;
-			goto done;
-		}
+		mwifiex_write_reg(adapter, reg->cmdrsp_addr_hi,
+				  (u32)((u64)cmdrsp_buf_pa >> 32));
 	}
 
 	cmd_buf_pa = MWIFIEX_SKB_DMA_ADDR(card->cmd_buf);
+
 	/* Write the lower 32bits of the physical address to reg->cmd_addr_lo */
-	if (mwifiex_write_reg(adapter, reg->cmd_addr_lo,
-			      (u32)cmd_buf_pa)) {
-		mwifiex_dbg(adapter, ERROR,
-			    "Failed to write download cmd to boot code.\n");
-		ret = -1;
-		goto done;
-	}
+	mwifiex_write_reg(adapter, reg->cmd_addr_lo, (u32)cmd_buf_pa);
+
 	/* Write the upper 32bits of the physical address to reg->cmd_addr_hi */
-	if (mwifiex_write_reg(adapter, reg->cmd_addr_hi,
-			      (u32)((u64)cmd_buf_pa >> 32))) {
-		mwifiex_dbg(adapter, ERROR,
-			    "Failed to write download cmd to boot code.\n");
-		ret = -1;
-		goto done;
-	}
+	mwifiex_write_reg(adapter, reg->cmd_addr_hi,
+			  (u32)((u64)cmd_buf_pa >> 32));
 
 	/* Write the command length to reg->cmd_size */
-	if (mwifiex_write_reg(adapter, reg->cmd_size,
-			      card->cmd_buf->len)) {
-		mwifiex_dbg(adapter, ERROR,
-			    "Failed to write cmd len to reg->cmd_size\n");
-		ret = -1;
-		goto done;
-	}
+	mwifiex_write_reg(adapter, reg->cmd_size, card->cmd_buf->len);
 
 	/* Ring the door bell */
-	if (mwifiex_write_reg(adapter, PCIE_CPU_INT_EVENT,
-			      CPU_INTR_DOOR_BELL)) {
-		mwifiex_dbg(adapter, ERROR,
-			    "Failed to assert door-bell intr\n");
-		ret = -1;
-		goto done;
-	}
-
-done:
-	if (ret)
-		adapter->cmd_sent = false;
+	mwifiex_write_reg(adapter, PCIE_CPU_INT_EVENT, CPU_INTR_DOOR_BELL);
 
 	return 0;
 }
@@ -1941,13 +1840,9 @@  static int mwifiex_pcie_process_cmd_complete(struct mwifiex_adapter *adapter)
 						   MWIFIEX_SKB_DMA_ADDR(skb),
 						   MWIFIEX_SLEEP_COOKIE_SIZE,
 						   DMA_FROM_DEVICE);
-			if (mwifiex_write_reg(adapter,
-					      PCIE_CPU_INT_EVENT,
-					      CPU_INTR_SLEEP_CFM_DONE)) {
-				mwifiex_dbg(adapter, ERROR,
-					    "Write register failed\n");
-				return -1;
-			}
+			mwifiex_write_reg(adapter,
+					  PCIE_CPU_INT_EVENT,
+					  CPU_INTR_SLEEP_CFM_DONE);
 			mwifiex_delay_for_sleep_cookie(adapter,
 						       MWIFIEX_MAX_DELAY_COUNT);
 			mwifiex_unmap_pci_memory(adapter, skb,
@@ -1980,18 +1875,11 @@  static int mwifiex_pcie_process_cmd_complete(struct mwifiex_adapter *adapter)
 		/* Clear the cmd-rsp buffer address in scratch registers. This
 		   will prevent firmware from writing to the same response
 		   buffer again. */
-		if (mwifiex_write_reg(adapter, reg->cmdrsp_addr_lo, 0)) {
-			mwifiex_dbg(adapter, ERROR,
-				    "cmd_done: failed to clear cmd_rsp_addr_lo\n");
-			return -1;
-		}
+		mwifiex_write_reg(adapter, reg->cmdrsp_addr_lo, 0);
+
 		/* Write the upper 32bits of the cmdrsp buffer physical
 		   address */
-		if (mwifiex_write_reg(adapter, reg->cmdrsp_addr_hi, 0)) {
-			mwifiex_dbg(adapter, ERROR,
-				    "cmd_done: failed to clear cmd_rsp_addr_hi\n");
-			return -1;
-		}
+		mwifiex_write_reg(adapter, reg->cmdrsp_addr_hi, 0);
 	}
 
 	return 0;
@@ -2098,12 +1986,8 @@  static int mwifiex_pcie_process_event_ready(struct mwifiex_adapter *adapter)
 		   we need to find a better method of managing these buffers.
 		*/
 	} else {
-		if (mwifiex_write_reg(adapter, PCIE_CPU_INT_EVENT,
-				      CPU_INTR_EVENT_DONE)) {
-			mwifiex_dbg(adapter, ERROR,
-				    "Write register failed\n");
-			return -1;
-		}
+		mwifiex_write_reg(adapter, PCIE_CPU_INT_EVENT,
+				  CPU_INTR_EVENT_DONE);
 	}
 
 	return 0;
@@ -2169,12 +2053,7 @@  static int mwifiex_pcie_event_complete(struct mwifiex_adapter *adapter,
 		    card->evtbd_rdptr, wrptr);
 
 	/* Write the event ring read pointer in to reg->evt_rdptr */
-	if (mwifiex_write_reg(adapter, reg->evt_rdptr,
-			      card->evtbd_rdptr)) {
-		mwifiex_dbg(adapter, ERROR,
-			    "event_complete: failed to read reg->evt_rdptr\n");
-		return -1;
-	}
+	mwifiex_write_reg(adapter, reg->evt_rdptr, card->evtbd_rdptr);
 
 	mwifiex_dbg(adapter, EVENT,
 		    "info: Check Events Again\n");
@@ -2471,21 +2350,12 @@  mwifiex_check_fw_status(struct mwifiex_adapter *adapter, u32 poll_num)
 	u32 tries;
 
 	/* Mask spurios interrupts */
-	if (mwifiex_write_reg(adapter, PCIE_HOST_INT_STATUS_MASK,
-			      HOST_INTR_MASK)) {
-		mwifiex_dbg(adapter, ERROR,
-			    "Write register failed\n");
-		return -1;
-	}
+	mwifiex_write_reg(adapter, PCIE_HOST_INT_STATUS_MASK, HOST_INTR_MASK);
 
 	mwifiex_dbg(adapter, INFO,
 		    "Setting driver ready signature\n");
-	if (mwifiex_write_reg(adapter, reg->drv_rdy,
-			      FIRMWARE_READY_PCIE)) {
-		mwifiex_dbg(adapter, ERROR,
-			    "Failed to write driver ready signature\n");
-		return -1;
-	}
+
+	mwifiex_write_reg(adapter, reg->drv_rdy, FIRMWARE_READY_PCIE);
 
 	/* Wait for firmware initialization event */
 	for (tries = 0; tries < poll_num; tries++) {
@@ -2571,12 +2441,7 @@  static void mwifiex_interrupt_status(struct mwifiex_adapter *adapter,
 		mwifiex_pcie_disable_host_int(adapter);
 
 		/* Clear the pending interrupts */
-		if (mwifiex_write_reg(adapter, PCIE_HOST_INT_STATUS,
-				      ~pcie_ireg)) {
-			mwifiex_dbg(adapter, ERROR,
-				    "Write register failed\n");
-			return;
-		}
+		mwifiex_write_reg(adapter, PCIE_HOST_INT_STATUS, ~pcie_ireg);
 	}
 
 	if (!adapter->pps_uapsd_mode &&
@@ -2671,13 +2536,9 @@  static int mwifiex_process_int_status(struct mwifiex_adapter *adapter)
 			}
 
 			if ((pcie_ireg != 0xFFFFFFFF) && (pcie_ireg)) {
-				if (mwifiex_write_reg(adapter,
-						      PCIE_HOST_INT_STATUS,
-						      ~pcie_ireg)) {
-					mwifiex_dbg(adapter, ERROR,
-						    "Write register failed\n");
-					return -1;
-				}
+				mwifiex_write_reg(adapter,
+						  PCIE_HOST_INT_STATUS,
+						  ~pcie_ireg);
 				if (!adapter->pps_uapsd_mode &&
 				    adapter->ps_state == PS_STATE_SLEEP) {
 					adapter->ps_state = PS_STATE_AWAKE;
@@ -2801,7 +2662,7 @@  mwifiex_pcie_reg_dump(struct mwifiex_adapter *adapter, char *drv_buf)
 static enum rdwr_status
 mwifiex_pcie_rdwr_firmware(struct mwifiex_adapter *adapter, u8 doneflag)
 {
-	int ret, tries;
+	int tries;
 	u8 ctrl_data;
 	u32 fw_status;
 	struct pcie_service_card *card = adapter->card;
@@ -2810,13 +2671,7 @@  mwifiex_pcie_rdwr_firmware(struct mwifiex_adapter *adapter, u8 doneflag)
 	if (mwifiex_read_reg(adapter, reg->fw_status, &fw_status))
 		return RDWR_STATUS_FAILURE;
 
-	ret = mwifiex_write_reg(adapter, reg->fw_dump_ctrl,
-				reg->fw_dump_host_ready);
-	if (ret) {
-		mwifiex_dbg(adapter, ERROR,
-			    "PCIE write err\n");
-		return RDWR_STATUS_FAILURE;
-	}
+	mwifiex_write_reg(adapter, reg->fw_dump_ctrl, reg->fw_dump_host_ready);
 
 	for (tries = 0; tries < MAX_POLL_TRIES; tries++) {
 		mwifiex_read_reg_byte(adapter, reg->fw_dump_ctrl, &ctrl_data);
@@ -2827,13 +2682,8 @@  mwifiex_pcie_rdwr_firmware(struct mwifiex_adapter *adapter, u8 doneflag)
 		if (ctrl_data != reg->fw_dump_host_ready) {
 			mwifiex_dbg(adapter, WARN,
 				    "The ctrl reg was changed, re-try again!\n");
-			ret = mwifiex_write_reg(adapter, reg->fw_dump_ctrl,
-						reg->fw_dump_host_ready);
-			if (ret) {
-				mwifiex_dbg(adapter, ERROR,
-					    "PCIE write err\n");
-				return RDWR_STATUS_FAILURE;
-			}
+			mwifiex_write_reg(adapter, reg->fw_dump_ctrl,
+					  reg->fw_dump_host_ready);
 		}
 		usleep_range(100, 200);
 	}
@@ -2852,7 +2702,6 @@  static void mwifiex_pcie_fw_dump(struct mwifiex_adapter *adapter)
 	u8 idx, i, read_reg, doneflag = 0;
 	enum rdwr_status stat;
 	u32 memory_size;
-	int ret;
 
 	if (!card->pcie.can_dump_fw)
 		return;
@@ -2906,12 +2755,8 @@  static void mwifiex_pcie_fw_dump(struct mwifiex_adapter *adapter)
 
 		if (memory_size == 0) {
 			mwifiex_dbg(adapter, MSG, "Firmware dump Finished!\n");
-			ret = mwifiex_write_reg(adapter, creg->fw_dump_ctrl,
-						creg->fw_dump_read_done);
-			if (ret) {
-				mwifiex_dbg(adapter, ERROR, "PCIE write err\n");
-				return;
-			}
+			mwifiex_write_reg(adapter, creg->fw_dump_ctrl,
+					  creg->fw_dump_read_done);
 			break;
 		}
 
@@ -3197,9 +3042,7 @@  static void mwifiex_cleanup_pcie(struct mwifiex_adapter *adapter)
 	if (fw_status == FIRMWARE_READY_PCIE) {
 		mwifiex_dbg(adapter, INFO,
 			    "Clearing driver ready signature\n");
-		if (mwifiex_write_reg(adapter, reg->drv_rdy, 0x00000000))
-			mwifiex_dbg(adapter, ERROR,
-				    "Failed to write driver not-ready signature\n");
+		mwifiex_write_reg(adapter, reg->drv_rdy, 0x00000000);
 	}
 
 	pci_disable_device(pdev);
@@ -3404,8 +3247,7 @@  static void mwifiex_pcie_down_dev(struct mwifiex_adapter *adapter)
 	const struct mwifiex_pcie_card_reg *reg = card->pcie.reg;
 	struct pci_dev *pdev = card->dev;
 
-	if (mwifiex_write_reg(adapter, reg->drv_rdy, 0x00000000))
-		mwifiex_dbg(adapter, ERROR, "Failed to write driver not-ready signature\n");
+	mwifiex_write_reg(adapter, reg->drv_rdy, 0x00000000);
 
 	pci_clear_master(pdev);