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

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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: e5f0dfa78a ("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
This commit is contained in:
Vijaya Krishna Nivarthi 2023-05-09 15:31:36 +05:30 committed by Mark Brown
parent ac9a78681b
commit 4c329f5da7
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1 changed files with 2 additions and 0 deletions
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drivers/spi/spi-geni-qcom.c
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@ -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);