From mboxrd@z Thu Jan  1 00:00:00 1970
From: LW@KARO-electronics.de (=?utf-8?Q?Lothar_Wa=C3=9Fmann?=)
Date: Mon, 8 Jul 2013 09:32:16 +0200
Subject: [PATCH v3 4/6] ARM: dts: imx6q{dl}: fix the wrong RTS/CTS pad name
In-Reply-To: <51DA5CA7.1050305@freescale.com>
References: <1373004752-21302-1-git-send-email-b32955@freescale.com>
 <1373004752-21302-5-git-send-email-b32955@freescale.com>
 <20130706050803.GC30164@S2101-09.ap.freescale.net>
 <20953.22066.706534.773272@ipc1.ka-ro>
 <51DA5CA7.1050305@freescale.com>
Message-ID: <20954.27392.875173.755391@ipc1.ka-ro>
To: linux-arm-kernel@lists.infradead.org
List-Id: linux-arm-kernel.lists.infradead.org

Hi,

Huang Shijie writes:
> ? 2013?07?07? 19:51, Lothar Wa?mann ??:
> > Hi,
> >
> > Shawn Guo writes:
> >> On Fri, Jul 05, 2013 at 02:12:30PM +0800, Huang Shijie wrote:
> >>> 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.
> Hi Lothar:
> 
> In our imx6 Soc, the CTS is used as a input signal, not as a output signal.
> 
> I checked two boards, one is imx6q ARM2 armidillo board, one is 
> imx6-sabreauto board,
> both the boards use the CTS as a input signal.
> 
that's the problem with the DTE/DCE mode. Depending on the DCEDTE bit
in the UARTx_UFCR we would need different pad configurations for
RTS/CTS because in DCE mode CTS is an output and in DTE mode it's an
input.
Thus the correct pad config value would need the input_sel on the CTS
pad definition for DTE mode and on the RTS pad definition for DCE
mode. Maybe something like:
#define MX6Q_PAD_EIM_D19__UART1_DCE_CTS_B             0x09c 0x3b0 0x000 0x4 0x0
#define MX6Q_PAD_EIM_D19__UART1_DCE_RTS_B             0x09c 0x3b0 0x91c 0x4 0x0
#define MX6Q_PAD_EIM_D19__UART1_DTE_CTS_B             0x09c 0x3b0 0x91c 0x4 0x0
#define MX6Q_PAD_EIM_D19__UART1_DTE_RTS_B             0x09c 0x3b0 0x000 0x4 0x0


Lothar Wa?mann
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