[PATCH v6 2/6] net: can: flexcan: move rx offload_add from probe to start

[Pankaj Bansal <pankaj.bansal@xxxxxxx>]

rx offload depends on number of message buffers, which in turn depends on
messgae buffer size. with the upcoming LX2160A SOC the message buffer size
can be configured to 72 bytes if it were to be used in CAN FD mode.

The current mode in which the flexcan is being operated is known at the
time of flexcan_open and not at the time of flexcan_probe.

Therefore, move the rx offload_add from flexcan_probe to flexcan_open.
correspondingly, move rx offload_delete form flexcan_remove to
flexcan_close.

Signed-off-by: Pankaj Bansal <pankaj.bansal@xxxxxxx>
---

Notes:
    V6:
    - No Change
    V5:
    - No Change
    V4:
    - handle rx offload delete in flexcan_start in case of any error after
      rx offload add.
    V3:
    - New patch
    V2:
    - Not existed

 drivers/net/can/flexcan.c | 77 +++++++++++++++++++------------------
 1 file changed, 40 insertions(+), 37 deletions(-)

diff --git a/drivers/net/can/flexcan.c b/drivers/net/can/flexcan.c
index 297d0914303f..7567c2e53eef 100644
--- a/drivers/net/can/flexcan.c
+++ b/drivers/net/can/flexcan.c
@@ -1105,6 +1105,7 @@ static void flexcan_chip_stop(struct net_device *dev)
 static int flexcan_open(struct net_device *dev)
 {
 	struct flexcan_priv *priv = netdev_priv(dev);
+	struct flexcan_regs __iomem *regs = priv->regs;
 	int err;
 
 	err = clk_prepare_enable(priv->clk_ipg);
@@ -1123,10 +1124,45 @@ static int flexcan_open(struct net_device *dev)
 	if (err)
 		goto out_close;
 
+	if (priv->devtype_data->quirks & FLEXCAN_QUIRK_USE_OFF_TIMESTAMP) {
+		priv->tx_mb_idx = FLEXCAN_TX_MB_OFF_TIMESTAMP;
+		priv->tx_mb_reserved = &regs->mb[FLEXCAN_TX_MB_RESERVED_OFF_TIMESTAMP];
+	} else {
+		priv->tx_mb_idx = FLEXCAN_TX_MB_OFF_FIFO;
+		priv->tx_mb_reserved = &regs->mb[FLEXCAN_TX_MB_RESERVED_OFF_FIFO];
+	}
+	priv->tx_mb = &regs->mb[priv->tx_mb_idx];
+
+	priv->reg_imask1_default = FLEXCAN_IFLAG_MB(priv->tx_mb_idx);
+	priv->reg_imask2_default = 0;
+
+	priv->offload.mailbox_read = flexcan_mailbox_read;
+
+	if (priv->devtype_data->quirks & FLEXCAN_QUIRK_USE_OFF_TIMESTAMP) {
+		u64 imask;
+
+		priv->offload.mb_first = FLEXCAN_RX_MB_OFF_TIMESTAMP_FIRST;
+		priv->offload.mb_last = FLEXCAN_RX_MB_OFF_TIMESTAMP_LAST;
+
+		imask = GENMASK_ULL(priv->offload.mb_last,
+				    priv->offload.mb_first);
+		priv->reg_imask1_default |= imask;
+		priv->reg_imask2_default |= imask >> 32;
+
+		err = can_rx_offload_add_timestamp(dev, &priv->offload);
+	} else {
+		priv->reg_imask1_default |= FLEXCAN_IFLAG_RX_FIFO_OVERFLOW |
+			FLEXCAN_IFLAG_RX_FIFO_AVAILABLE;
+		err = can_rx_offload_add_fifo(dev, &priv->offload,
+					      FLEXCAN_NAPI_WEIGHT);
+	}
+	if (err)
+		goto out_free_irq;
+
 	/* start chip and queuing */
 	err = flexcan_chip_start(dev);
 	if (err)
-		goto out_free_irq;
+		goto out_offload_del;
 
 	can_led_event(dev, CAN_LED_EVENT_OPEN);
 
@@ -1135,6 +1171,8 @@ static int flexcan_open(struct net_device *dev)
 
 	return 0;
 
+ out_offload_del:
+	can_rx_offload_del(&priv->offload);
  out_free_irq:
 	free_irq(dev->irq, dev);
  out_close:
@@ -1155,6 +1193,7 @@ static int flexcan_close(struct net_device *dev)
 	can_rx_offload_disable(&priv->offload);
 	flexcan_chip_stop(dev);
 
+	can_rx_offload_del(&priv->offload);
 	free_irq(dev->irq, dev);
 	clk_disable_unprepare(priv->clk_per);
 	clk_disable_unprepare(priv->clk_ipg);
@@ -1366,39 +1405,6 @@ static int flexcan_probe(struct platform_device *pdev)
 	priv->devtype_data = devtype_data;
 	priv->reg_xceiver = reg_xceiver;
 
-	if (priv->devtype_data->quirks & FLEXCAN_QUIRK_USE_OFF_TIMESTAMP) {
-		priv->tx_mb_idx = FLEXCAN_TX_MB_OFF_TIMESTAMP;
-		priv->tx_mb_reserved = &regs->mb[FLEXCAN_TX_MB_RESERVED_OFF_TIMESTAMP];
-	} else {
-		priv->tx_mb_idx = FLEXCAN_TX_MB_OFF_FIFO;
-		priv->tx_mb_reserved = &regs->mb[FLEXCAN_TX_MB_RESERVED_OFF_FIFO];
-	}
-	priv->tx_mb = &regs->mb[priv->tx_mb_idx];
-
-	priv->reg_imask1_default = FLEXCAN_IFLAG_MB(priv->tx_mb_idx);
-	priv->reg_imask2_default = 0;
-
-	priv->offload.mailbox_read = flexcan_mailbox_read;
-
-	if (priv->devtype_data->quirks & FLEXCAN_QUIRK_USE_OFF_TIMESTAMP) {
-		u64 imask;
-
-		priv->offload.mb_first = FLEXCAN_RX_MB_OFF_TIMESTAMP_FIRST;
-		priv->offload.mb_last = FLEXCAN_RX_MB_OFF_TIMESTAMP_LAST;
-
-		imask = GENMASK_ULL(priv->offload.mb_last, priv->offload.mb_first);
-		priv->reg_imask1_default |= imask;
-		priv->reg_imask2_default |= imask >> 32;
-
-		err = can_rx_offload_add_timestamp(dev, &priv->offload);
-	} else {
-		priv->reg_imask1_default |= FLEXCAN_IFLAG_RX_FIFO_OVERFLOW |
-			FLEXCAN_IFLAG_RX_FIFO_AVAILABLE;
-		err = can_rx_offload_add_fifo(dev, &priv->offload, FLEXCAN_NAPI_WEIGHT);
-	}
-	if (err)
-		goto failed_offload;
-
 	err = register_flexcandev(dev);
 	if (err) {
 		dev_err(&pdev->dev, "registering netdev failed\n");
@@ -1412,7 +1418,6 @@ static int flexcan_probe(struct platform_device *pdev)
 
 	return 0;
 
- failed_offload:
  failed_register:
 	free_candev(dev);
 	return err;
@@ -1421,10 +1426,8 @@ static int flexcan_probe(struct platform_device *pdev)
 static int flexcan_remove(struct platform_device *pdev)
 {
 	struct net_device *dev = platform_get_drvdata(pdev);
-	struct flexcan_priv *priv = netdev_priv(dev);
 
 	unregister_flexcandev(dev);
-	can_rx_offload_del(&priv->offload);
 	free_candev(dev);
 
 	return 0;
-- 
2.17.1