Commit d49184b7 authored by Marc Kleine-Budde's avatar Marc Kleine-Budde
Browse files

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



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: default avatarStefan Althöfer <Stefan.Althoefer@janztec.com>
Tested-by: default avatarThomas Kopp <thomas.kopp@microchip.com>
Signed-off-by: default avatarMarc Kleine-Budde <mkl@pengutronix.de>
parent e793c724

drivers/net/can/spi/mcp251xfd/mcp251xfd-rx.c

+32 −16
Original line number Diff line number Diff line
@@ -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;