spi: spi-geni-qcom: Select FIFO mode for chip select

[ Upstream commit 4c329f5da7cfa366bacfda1328a025dd38951317 ]

Spi geni driver switches between FIFO and DMA modes based on xfer length.
FIFO mode relies on M_CMD_DONE_EN interrupt for completion while DMA mode
relies on XX_DMA_DONE.
During dynamic switching, if FIFO mode is chosen, FIFO related interrupts
are enabled and DMA related interrupts are disabled. And viceversa.
Chip select shares M_CMD_DONE_EN interrupt with FIFO to check completion.
Now, if a chip select operation is preceded by a DMA xfer, M_CMD_DONE_EN
interrupt would have been disabled and hence it will never receive one
resulting in timeout.

For chip select, in addition to setting the xfer mode to FIFO,
select_mode() to FIFO so that required interrupts are enabled.

Fixes: e5f0dfa78ac7 ("spi: spi-geni-qcom: Add support for SE DMA mode")
Suggested-by: Praveen Talari <quic_ptalari@quicinc.com
Signed-off-by: Vijaya Krishna Nivarthi <quic_vnivarth@quicinc.com
Reviewed-by: Douglas Anderson <dianders@chromium.org
Link: https://lore.kernel.org/r/1683626496-9685-1-git-send-email-quic_vnivarth@quicinc.com
Signed-off-by: Mark Brown <broonie@kernel.org
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/spi/spi-geni-qcom.c b/drivers/spi/spi-geni-qcom.c
index babb039bcb431d99186f4f9d93c8cbeac61515c3..b106faf21a7238f12155964377cf1c2eddf4f621 100644 (file)
--- a/drivers/spi/spi-geni-qcom.c
+++ b/drivers/spi/spi-geni-qcom.c
@@ -294,6 +294,8 @@ static void spi_geni_set_cs(struct spi_device *slv, bool set_flag)
        mas->cs_flag = set_flag;
        /* set xfer_mode to FIFO to complete cs_done in isr */
        mas->cur_xfer_mode = GENI_SE_FIFO;
+       geni_se_select_mode(se, mas->cur_xfer_mode);
+
        reinit_completion(&mas->cs_done);
        if (set_flag)
                geni_se_setup_m_cmd(se, SPI_CS_ASSERT, 0);