6.10-stable review patch. If anyone has any objections, please let me know.
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From: Marc Kleine-Budde mkl@pengutronix.de
[ Upstream commit d49184b7b585f9da7ee546b744525f62117019f6 ]
This is a preparation patch.
Sending the UINC messages followed by incrementing the tail pointer will be called in more than one place in 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.
Tested-by: Stefan Althöfer Stefan.Althoefer@janztec.com Tested-by: Thomas Kopp thomas.kopp@microchip.com Signed-off-by: Marc Kleine-Budde mkl@pengutronix.de Stable-dep-of: 85505e585637 ("can: mcp251xfd: rx: prepare to workaround broken RX FIFO head index erratum") Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/can/spi/mcp251xfd/mcp251xfd-rx.c | 48 +++++++++++++------- 1 file changed, 32 insertions(+), 16 deletions(-)
diff --git a/drivers/net/can/spi/mcp251xfd/mcp251xfd-rx.c b/drivers/net/can/spi/mcp251xfd/mcp251xfd-rx.c index ced8d9c81f8c..5e2f39de88f3 100644 --- a/drivers/net/can/spi/mcp251xfd/mcp251xfd-rx.c +++ b/drivers/net/can/spi/mcp251xfd/mcp251xfd-rx.c @@ -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;