Toggling UART2 UART pins

[pro-supportengi]

How do we toggle the UART2 UART pins using SYSFS and without using GPIOs?  We want to toggle the pin muxed UART2 UART pins directly without using GPIOs, how can we do this using SDK 2.0?  What is required on QorIQ LS1043A?

[Pavel]

If UART pins is needed use POSIX possibilities of serial driver.

Look at the following page for setting/getting modem control signals (RTS, CTS and so on except RXD and TXD):

http://digilander.libero.it/robang/rubrica/serial.htm

Have a great day,
Pavel Chubakov

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[pro-supportengi]

Thanks Pavel that was much more helpful.  Now please provide the code in the serial driver that that toggles the pins.

If these pins are assigned to UART, RTS, CTS and so on (except RXD and TXD) can be toggled using serial driver:

What driver is needed for these pins toggling? (yes and which section of code in the driver illustrates toggling the pins)? Please provide this information for customers.

Also, for the GPIO pins, I'll check the kernel config and make sure sysfs is enabled. Thanks!!

[Pavel]

If these pins are not assigned to UART, these are GPIO pins or LPUART pins or FTM pins of the LS1043a. See the Table 3-3 Reference Manual.

If these pins are GPIO, these pins can be togged using sysfs.

If these pins are assigned to UART, RTS, CTS and so on (except RXD and TXD) can be toggled using serial driver:

What driver is needed for these pins toggling?

NXP SDK supports sysfs for GPIO using. See attached screenshot.

Have a great day,
Pavel Chubakov

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[pro-supportengi]

Again, I'm not asking how to assign the pins (plus your answers are always too general to be of any help).  I already know they have to be assigned by the RCW, so that was not the question. The question is how can I through software toggle the UART pins without using GPIOs?  You are not saying the pinmux pins cannot be toggled through software are you?

They can be toggled using GPIOs, so UART pin muxed pins can be directly toggled through software, how do we do this?

Someone else should likely provide an answer to this question since Pavel doesn't understand the question.

How can one toggle pin muxed pins in the software AFTER the pins have been assigned by the RCW and without using GPIOs?  One can assign the UART pins to GPIOs and toggle them through SYSFS.  How can one avoid having to do this and toggle the pin muxed pins without having having to assign them to GPIOs?  If toggling the pins without using GPIOs is not supported, please explain what that means?

Please don't close the ticket and assume it has been answered please.

[Pavel]

The LS1043a UART pins can be assigned to UART or GPIO using RCW only. There is no possibility for assigning the LS1043A UART pins from Linux or u-boot. It is hardware limitation of the LS1043A.

Have a great day,
Pavel Chubakov

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[pro-supportengi]

Sorry this information did not answer the question and wasn't helpful.  Too general and not sufficiently specific enough.  Opening another question for specific details on how to toggle a pinmux UART2 pin in SDK 2.0.

The question was, how do customers access UART2 pinmuxed pins on the LS1043ARDB, not using a general serial document that doesn’t describe how to toggle pinmuxed pins similar to toggling GPIOs. As customers we want to toggle the pinmuxed pins.

Please provide details on how to toggle pinmuxed pins for UART2 in SDK 2.0.

[Pavel]

Look at the following document about sysfs possibilities:

https://www.kernel.org/doc/Documentation/gpio/sysfs.txt

This document shows that sysfs is used for GPIO using under Linux.

If UART pins is needed use POSIX possibilities of serial driver.

Look at the following page for setting/getting modem control signals (RTS, CTS and so on except RXD and TXD):

http://digilander.libero.it/robang/rubrica/serial.htm

Have a great day,
Pavel Chubakov

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Note: If this post answers your question, please click the Correct Answer button. Thank you!
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