6.15-stable review patch. If anyone has any objections, please let me know.
------------------
From: Félix Piédallu felix.piedallu@non.se.com
[ Upstream commit 10c24e0d2f7cd2bc8a847cf750f01301ce67dbc8 ]
When the last transfer of a SPI message has the cs_change flag, the CS is kept asserted after the message. The next message can't use multi-mode because the CS will be briefly deasserted before the first transfer.
Remove the early exit of the list_for_each_entry because the last transfer actually needs to be always checked.
Fixes: d153ff4056cb ("spi: omap2-mcspi: Add support for MULTI-mode") Signed-off-by: Félix Piédallu felix.piedallu@non.se.com Link: https://patch.msgid.link/20250606-cs_change_fix-v1-2-27191a98a2e5@non.se.com Signed-off-by: Mark Brown broonie@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/spi/spi-omap2-mcspi.c | 20 ++++++++++---------- 1 file changed, 10 insertions(+), 10 deletions(-)
diff --git a/drivers/spi/spi-omap2-mcspi.c b/drivers/spi/spi-omap2-mcspi.c index e834fb42fd4ba..70bb74b3bd9c3 100644 --- a/drivers/spi/spi-omap2-mcspi.c +++ b/drivers/spi/spi-omap2-mcspi.c @@ -134,6 +134,7 @@ struct omap2_mcspi { size_t max_xfer_len; u32 ref_clk_hz; bool use_multi_mode; + bool last_msg_kept_cs; };
struct omap2_mcspi_cs { @@ -1269,6 +1270,10 @@ static int omap2_mcspi_prepare_message(struct spi_controller *ctlr, * multi-mode is applicable. */ mcspi->use_multi_mode = true; + + if (mcspi->last_msg_kept_cs) + mcspi->use_multi_mode = false; + list_for_each_entry(tr, &msg->transfers, transfer_list) { if (!tr->bits_per_word) bits_per_word = msg->spi->bits_per_word; @@ -1289,22 +1294,17 @@ static int omap2_mcspi_prepare_message(struct spi_controller *ctlr,
if (list_is_last(&tr->transfer_list, &msg->transfers)) { /* Check if transfer asks to keep the CS status after the whole message */ - if (tr->cs_change) + if (tr->cs_change) { mcspi->use_multi_mode = false; + mcspi->last_msg_kept_cs = true; + } else { + mcspi->last_msg_kept_cs = false; + } } else { /* Check if transfer asks to change the CS status after the transfer */ if (!tr->cs_change) mcspi->use_multi_mode = false; } - - /* - * If at least one message is not compatible, switch back to single mode - * - * The bits_per_word of certain transfer can be different, but it will have no - * impact on the signal itself. - */ - if (!mcspi->use_multi_mode) - break; }
omap2_mcspi_set_mode(ctlr);