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Does i.MX8M Mini support swapping RTS and CTS on ECSPI2_SS0 and ECSPI2_MISO?

Question asked by John Weber on Jun 4, 2019
Latest reply on Jun 5, 2019 by Wigros Sun

Does i.MX8M Mini support swapping RTS and CTS on ECSPI2_SS0 and ECSPI2_MISO?

 

According to both the default pins-imx8mm.h file in the NXP kernel (include/dt-bindings/pinctrl/pins-imx8mm.h), there are settings for this:

 

...

#define MX8MM_IOMUXC_ECSPI2_MISO_UART4_DCE_CTS_B                            0x20C 0x474 0x000 0x1 0x0
#define MX8MM_IOMUXC_ECSPI2_MISO_UART4_DTE_RTS_B                            0x20C 0x474 0x508 0x1 0x0

...

#define MX8MM_IOMUXC_ECSPI2_SS0_UART4_DCE_RTS_B                             0x210 0x478 0x508 0x1 0x1
#define MX8MM_IOMUXC_ECSPI2_SS0_UART4_DTE_CTS_B                             0x210 0x478 0x000 0x1 0x0

...

 

In addition, the pins tool (v5, downloaded today), also indicates this:

For uart4_cts_b, these are the options:

For uart4_rts_b, these are the options:

 

According to the reference manual, rev 1, there is some support for the source pin of UART4_RTS_B, through the daisy chain (input select). There is no corresponding input select for UART_CTS_B.

 

Is it possible that there are settings both in the kernel and in the pins tool that are not correct?

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