can: mcp251xfd: mcp251xfd_handle_rxif_ring_uinc(): factor out in separate function

[ 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>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Marc Kleine-Budde 2023-01-11 20:25:48 +01:00 committed by Greg Kroah-Hartman
parent 62ca6d3a90
commit 2370061f07
1 changed files with 32 additions and 16 deletions

View File

@ -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;