This is a preparation patch.
The sending of the UINC messages followed by the incrementing of the
tail pointer will be called from more 1 place in the upcoming patches,
so factor this out into a separate function.
Also make mcp251xfd_handle_rxif_ring_uinc() safe to be called with a
"len" of 0.
Signed-off-by: Marc Kleine-Budde <mkl@xxxxxxxxxxxxxx>
---
drivers/net/can/spi/mcp251xfd/mcp251xfd-rx.c | 50 +++++++++++++-------
1 file changed, 33 insertions(+), 17 deletions(-)
diff --git a/drivers/net/can/spi/mcp251xfd/mcp251xfd-rx.c b/drivers/net/can/spi/mcp251xfd/mcp251xfd-rx.c
index d946d93b22e0..1b18867a9cd5 100644
--- a/drivers/net/can/spi/mcp251xfd/mcp251xfd-rx.c
+++ b/drivers/net/can/spi/mcp251xfd/mcp251xfd-rx.c
@@ -2,7 +2,7 @@
//
// mcp251xfd - Microchip MCP251xFD Family CAN controller driver
//
-// Copyright (c) 2019, 2020, 2021 Pengutronix,
+// Copyright (c) 2019, 2020, 2021, 2023 Pengutronix,
// Marc Kleine-Budde <kernel@xxxxxxxxxxxxxx>
//
// Based on:
@@ -197,6 +197,37 @@ mcp251xfd_rx_obj_read(const struct mcp251xfd_priv *priv,
return err;
}
+static int
+mcp251xfd_handle_rxif_ring_uinc(const struct mcp251xfd_priv *priv,
+ struct mcp251xfd_rx_ring *ring,
+ u8 len)
+{
+ int offset;
+ int err;
+
+ if (!len)
+ return 0;
+
+ /* Increment the RX FIFO tail pointer 'len' times in a
+ * single SPI message.
+ *
+ * Note:
+ * Calculate offset, so that the SPI transfer ends on
+ * the last message of the uinc_xfer array, which has
+ * "cs_change == 0", to properly deactivate the chip
+ * select.
+ */
+ offset = ARRAY_SIZE(ring->uinc_xfer) - len;
+ err = spi_sync_transfer(priv->spi,
+ ring->uinc_xfer + offset, len);
+ if (err)
+ return err;
+
+ ring->tail += len;
+
+ return 0;
+}
+
static int
mcp251xfd_handle_rxif_ring(struct mcp251xfd_priv *priv,
struct mcp251xfd_rx_ring *ring)
@@ -210,8 +241,6 @@ mcp251xfd_handle_rxif_ring(struct mcp251xfd_priv *priv,
return err;
while ((len = mcp251xfd_get_rx_linear_len(ring))) {
- int offset;
-
rx_tail = mcp251xfd_get_rx_tail(ring);
err = mcp251xfd_rx_obj_read(priv, ring, hw_rx_obj,
@@ -227,22 +256,9 @@ mcp251xfd_handle_rxif_ring(struct mcp251xfd_priv *priv,
return err;
}
- /* Increment the RX FIFO tail pointer 'len' times in a
- * single SPI message.
- *
- * Note:
- * Calculate offset, so that the SPI transfer ends on
- * the last message of the uinc_xfer array, which has
- * "cs_change == 0", to properly deactivate the chip
- * select.
- */
- offset = ARRAY_SIZE(ring->uinc_xfer) - len;
- err = spi_sync_transfer(priv->spi,
- ring->uinc_xfer + offset, len);
+ err = mcp251xfd_handle_rxif_ring_uinc(priv, ring, len);
if (err)
return err;
-
- ring->tail += len;
}
return 0;
--
2.39.0
