From 98621ed011c57ba6e52e01a5982b221c9943b6d9 Mon Sep 17 00:00:00 2001 From: Sowjanya Komatineni Date: Mon, 21 Dec 2020 13:17:35 -0800 Subject: spi: spi-mem: Mark dummy transfers by setting dummy_data bit This patch marks dummy transfer by setting dummy_data bit to 1. Controllers supporting dummy transfer by hardware use this bit field to skip software transfer of dummy bytes and use hardware dummy bytes transfer. Signed-off-by: Sowjanya Komatineni Link: https://lore.kernel.org/r/1608585459-17250-6-git-send-email-skomatineni@nvidia.com Signed-off-by: Mark Brown --- drivers/spi/spi-mem.c | 1 + include/linux/spi/spi.h | 2 ++ 2 files changed, 3 insertions(+) diff --git a/drivers/spi/spi-mem.c b/drivers/spi/spi-mem.c index f3a3f196e628..c64371ce6c38 100644 --- a/drivers/spi/spi-mem.c +++ b/drivers/spi/spi-mem.c @@ -354,6 +354,7 @@ int spi_mem_exec_op(struct spi_mem *mem, const struct spi_mem_op *op) xfers[xferpos].tx_buf = tmpbuf + op->addr.nbytes + 1; xfers[xferpos].len = op->dummy.nbytes; xfers[xferpos].tx_nbits = op->dummy.buswidth; + xfers[xferpos].dummy_data = 1; spi_message_add_tail(&xfers[xferpos], &msg); xferpos++; totalxferlen += op->dummy.nbytes; diff --git a/include/linux/spi/spi.h b/include/linux/spi/spi.h index 9bfdfaf286eb..797ef28fa7d5 100644 --- a/include/linux/spi/spi.h +++ b/include/linux/spi/spi.h @@ -825,6 +825,7 @@ extern void spi_res_release(struct spi_controller *ctlr, * transfer. If 0 the default (from @spi_device) is used. * @bits_per_word: select a bits_per_word other than the device default * for this transfer. If 0 the default (from @spi_device) is used. + * @dummy_data: indicates transfer is dummy bytes transfer. * @cs_change: affects chipselect after this transfer completes * @cs_change_delay: delay between cs deassert and assert when * @cs_change is set and @spi_transfer is not the last in @spi_message @@ -937,6 +938,7 @@ struct spi_transfer { struct sg_table tx_sg; struct sg_table rx_sg; + unsigned dummy_data:1; unsigned cs_change:1; unsigned tx_nbits:3; unsigned rx_nbits:3; -- cgit v1.2.3