Unverified Commit 652ffad1 authored by Eddie James's avatar Eddie James Committed by Mark Brown
Browse files

spi: fsi: Batch TX operations 



Batch sequential write transfers up to the max TX size (40 bytes).
This controller must specify a max transfer size of only 8 bytes for
RX operations.

Signed-off-by: default avatarEddie James <eajames@linux.ibm.com>
Link: https://patch.msgid.link/20250131200158.732898-1-eajames@linux.ibm.com


Signed-off-by: default avatarMark Brown <broonie@kernel.org>
parent 26a756fc

drivers/spi/spi-fsi.c

+13 −0
Original line number Diff line number Diff line
@@ -479,6 +479,19 @@ static int fsi_spi_transfer_one_message(struct spi_controller *ctlr, 


				shift = SPI_FSI_SEQUENCE_SHIFT_IN(next->len);

				fsi_spi_sequence_add(&seq, shift);

			} else if (next->tx_buf) {

				if ((next->len + transfer->len) > (SPI_FSI_MAX_TX_SIZE + 8)) {

					rc = -EINVAL;

					goto error;

				}



				len = next->len;

				while (len > 8) {

					fsi_spi_sequence_add(&seq,

							     SPI_FSI_SEQUENCE_SHIFT_OUT(8));

					len -= 8;

				}

				fsi_spi_sequence_add(&seq, SPI_FSI_SEQUENCE_SHIFT_OUT(len));

			} else {

				next = NULL;

			}