From 652ffad172d089acb1a20e5fde1b66e687832b06 Mon Sep 17 00:00:00 2001 From: Eddie James Date: Fri, 31 Jan 2025 14:01:58 -0600 Subject: [PATCH] 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: Eddie James Link: https://patch.msgid.link/20250131200158.732898-1-eajames@linux.ibm.com Signed-off-by: Mark Brown --- drivers/spi/spi-fsi.c | 13 +++++++++++++ 1 file changed, 13 insertions(+) diff --git a/drivers/spi/spi-fsi.c b/drivers/spi/spi-fsi.c index fc9e33be1e0e7..e01c63d23b64d 100644 --- a/drivers/spi/spi-fsi.c +++ b/drivers/spi/spi-fsi.c @@ -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; } -- 2.39.5