can: mcp251xfd: mcp251xfd_ring_init(): split ring_init into separate functions

This patch splits the initialization of the TEF, TX and RX FIFO in the
mcp251xfd_ring_init() function into separate functions. This is a
preparation patch to move the RX FIFO in front of the TX FIFO.

Link: https://lore.kernel.org/all/20220217103826.2299157-3-mkl@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

diff --git a/drivers/net/can/spi/mcp251xfd/mcp251xfd-ring.c b/drivers/net/can/spi/mcp251xfd/mcp251xfd-ring.c
index 6e394ac0bc5e2cb2da41c2ca514696eabfe1ec2e..b9300554543ecfe7e68ae04b6b21f5cfe703e10a 100644 (file)
--- a/drivers/net/can/spi/mcp251xfd/mcp251xfd-ring.c
+++ b/drivers/net/can/spi/mcp251xfd/mcp251xfd-ring.c
@@ -52,6 +52,45 @@ mcp251xfd_cmd_prepare_write_reg(const struct mcp251xfd_priv *priv,
        return len;
 }
 
+static void mcp251xfd_ring_init_tef(struct mcp251xfd_priv *priv)
+{
+       struct mcp251xfd_tef_ring *tef_ring;
+       struct spi_transfer *xfer;
+       u32 val;
+       u16 addr;
+       u8 len;
+       int i;
+
+       /* TEF */
+       tef_ring = priv->tef;
+       tef_ring->head = 0;
+       tef_ring->tail = 0;
+
+       /* FIFO increment TEF tail pointer */
+       addr = MCP251XFD_REG_TEFCON;
+       val = MCP251XFD_REG_TEFCON_UINC;
+       len = mcp251xfd_cmd_prepare_write_reg(priv, &tef_ring->uinc_buf,
+                                             addr, val, val);
+
+       for (i = 0; i < ARRAY_SIZE(tef_ring->uinc_xfer); i++) {
+               xfer = &tef_ring->uinc_xfer[i];
+               xfer->tx_buf = &tef_ring->uinc_buf;
+               xfer->len = len;
+               xfer->cs_change = 1;
+               xfer->cs_change_delay.value = 0;
+               xfer->cs_change_delay.unit = SPI_DELAY_UNIT_NSECS;
+       }
+
+       /* "cs_change == 1" on the last transfer results in an active
+        * chip select after the complete SPI message. This causes the
+        * controller to interpret the next register access as
+        * data. Set "cs_change" of the last transfer to "0" to
+        * properly deactivate the chip select at the end of the
+        * message.
+        */
+       xfer->cs_change = 0;
+}
+
 static void
 mcp251xfd_tx_ring_init_tx_obj(const struct mcp251xfd_priv *priv,
                              const struct mcp251xfd_tx_ring *ring,
@@ -88,50 +127,15 @@ mcp251xfd_tx_ring_init_tx_obj(const struct mcp251xfd_priv *priv,
                                        ARRAY_SIZE(tx_obj->xfer));
 }
 
-void mcp251xfd_ring_init(struct mcp251xfd_priv *priv)
+static void mcp251xfd_ring_init_tx(struct mcp251xfd_priv *priv)
 {
-       struct mcp251xfd_tef_ring *tef_ring;
        struct mcp251xfd_tx_ring *tx_ring;
-       struct mcp251xfd_rx_ring *rx_ring, *prev_rx_ring = NULL;
        struct mcp251xfd_tx_obj *tx_obj;
-       struct spi_transfer *xfer;
        u32 val;
        u16 addr;
        u8 len;
-       int i, j;
-
-       netdev_reset_queue(priv->ndev);
-
-       /* TEF */
-       tef_ring = priv->tef;
-       tef_ring->head = 0;
-       tef_ring->tail = 0;
-
-       /* FIFO increment TEF tail pointer */
-       addr = MCP251XFD_REG_TEFCON;
-       val = MCP251XFD_REG_TEFCON_UINC;
-       len = mcp251xfd_cmd_prepare_write_reg(priv, &tef_ring->uinc_buf,
-                                             addr, val, val);
-
-       for (j = 0; j < ARRAY_SIZE(tef_ring->uinc_xfer); j++) {
-               xfer = &tef_ring->uinc_xfer[j];
-               xfer->tx_buf = &tef_ring->uinc_buf;
-               xfer->len = len;
-               xfer->cs_change = 1;
-               xfer->cs_change_delay.value = 0;
-               xfer->cs_change_delay.unit = SPI_DELAY_UNIT_NSECS;
-       }
-
-       /* "cs_change == 1" on the last transfer results in an active
-        * chip select after the complete SPI message. This causes the
-        * controller to interpret the next register access as
-        * data. Set "cs_change" of the last transfer to "0" to
-        * properly deactivate the chip select at the end of the
-        * message.
-        */
-       xfer->cs_change = 0;
+       int i;
 
-       /* TX */
        tx_ring = priv->tx;
        tx_ring->head = 0;
        tx_ring->tail = 0;
@@ -147,8 +151,19 @@ void mcp251xfd_ring_init(struct mcp251xfd_priv *priv)
 
        mcp251xfd_for_each_tx_obj(tx_ring, tx_obj, i)
                mcp251xfd_tx_ring_init_tx_obj(priv, tx_ring, tx_obj, len, i);
+}
+
+static void mcp251xfd_ring_init_rx(struct mcp251xfd_priv *priv)
+{
+       struct mcp251xfd_rx_ring *rx_ring, *prev_rx_ring = NULL;
+       struct mcp251xfd_tx_ring *tx_ring;
+       struct spi_transfer *xfer;
+       u32 val;
+       u16 addr;
+       u8 len;
+       int i, j;
 
-       /* RX */
+       tx_ring = priv->tx;
        mcp251xfd_for_each_rx_ring(priv, rx_ring, i) {
                rx_ring->head = 0;
                rx_ring->tail = 0;
@@ -192,6 +207,15 @@ void mcp251xfd_ring_init(struct mcp251xfd_priv *priv)
        }
 }
 
+void mcp251xfd_ring_init(struct mcp251xfd_priv *priv)
+{
+       netdev_reset_queue(priv->ndev);
+
+       mcp251xfd_ring_init_tef(priv);
+       mcp251xfd_ring_init_tx(priv);
+       mcp251xfd_ring_init_rx(priv);
+}
+
 void mcp251xfd_ring_free(struct mcp251xfd_priv *priv)
 {
        int i;