[PATCH v3 4/6] ARM: dts: imx6q{dl}: fix the wrong RTS/CTS pad name
From: Lothar Waßmann <hidden>
Date: 2013-07-08 08:03:49
Also in:
linux-serial
Hi, Russell King - ARM Linux writes:
On Sun, Jul 07, 2013 at 01:51:14PM +0200, Lothar Wa?mann wrote:quoted
Hi, Shawn Guo writes:quoted
On Fri, Jul 05, 2013 at 02:12:30PM +0800, Huang Shijie wrote:quoted
There is something wrong with the RTS/CTS pads: The RTS pad is assigned with the CTS's value; while the CTS pad is assigned with the RTS's value.So basically, you are saying that select_input should be set up for CTS rather than RTS. It seems that the people who generated the macro got the wrong input from developer.programming 'select_input' only makes sense for inputs, not outputs. Since CTS is an output signal, select_input only makes sense for the RTS function of the pads.Note: If you are a DTE, then RTS is an output, CTS is an input. If you are a DCE, then RTS is an input and CTS is an output (normally on a standard UART, you just swap the wiring for RTS and CTS but really that's all that is going on.) So swapping them in software should be acceptable too, provided you're not having to disable any auto flow control facilities.
Freescale had decided to implement their UARTs on the i.MX SoCs as DCE and later added a bit to switch between DCE and DTE mode. That's where all the confusion comes from. Lothar Wa?mann -- ___________________________________________________________ Ka-Ro electronics GmbH | Pascalstra?e 22 | D - 52076 Aachen Phone: +49 2408 1402-0 | Fax: +49 2408 1402-10 Gesch?ftsf?hrer: Matthias Kaussen Handelsregistereintrag: Amtsgericht Aachen, HRB 4996 www.karo-electronics.de | info at karo-electronics.de ___________________________________________________________