[PATCH 1/2] RFC: ARM: dts: imx7d-sdb: remove 100k pull-down on USDHCx clock

[A.s. Dong]

Hi Troy,

> -----Original Message-----
> From: Troy Kisky [mailto:troy.kisky at boundarydevices.com]
> Sent: Friday, June 16, 2017 1:46 AM
> To: A.s. Dong; Shawn Guo; Frank Li
> Cc: shawn.guo at linaro.org; Fabio Estevam; gary.bisson at boundarydevices.com;
> linux-arm-kernel at lists.infradead.org
> Subject: Re: [PATCH 1/2] RFC: ARM: dts: imx7d-sdb: remove 100k pull-down
> on USDHCx clock
> 
> On 6/14/2017 9:31 PM, A.s. Dong wrote:
> > Hi Troy,
> >
> >> -----Original Message-----
> >> From: Shawn Guo [mailto:shawnguo at kernel.org]
> >> Sent: Thursday, June 15, 2017 11:39 AM
> >> To: Troy Kisky; A.s. Dong; Frank Li
> >> Cc: shawn.guo at linaro.org; Fabio Estevam;
> >> gary.bisson at boundarydevices.com; linux-arm-kernel at lists.infradead.org
> >> Subject: Re: [PATCH 1/2] RFC: ARM: dts: imx7d-sdb: remove 100k
> >> pull-down on USDHCx clock
> >>
> >> On Wed, Jun 07, 2017 at 10:45:41AM -0700, Troy Kisky wrote:
> >>> No i.mx6q board uses a 100k pull-down on clock, why should i.mx7d ?
> >>>
> >
> > I saw the mx7d evk clk resistor pull-down is DNP, then why we disable
> > internal pad pull-down?
> 
> 
> That sounds like a very good reason to disable to me.
> Why rely on a DNP? Also, consistency with imx6 is nice.
> 

Sorry missed your reply.

Not quite understand your point.
We would like to pull down the clk signal in default state,
But due to the board pull-down resistor is DNP (not exist),
That's why we use internal pull down function instead.

Regards
Dong Aisheng

> 
> >
> > Regards
> > Dong Aisheng
> >
> >>> Signed-off-by: Troy Kisky <troy.kisky at boundarydevices.com>
> >>
> >> Add Dong and Frank who may help to confirm.
> >>
> >> Shawn
> >>
> >>> ---
> >>>  arch/arm/boot/dts/imx7d-sdb.dts | 14 +++++++-------
> >>>  1 file changed, 7 insertions(+), 7 deletions(-)
> >>>
> >>> diff --git a/arch/arm/boot/dts/imx7d-sdb.dts
> >>> b/arch/arm/boot/dts/imx7d-sdb.dts index 54c4540..cab9208 100644
> >>> --- a/arch/arm/boot/dts/imx7d-sdb.dts
> >>> +++ b/arch/arm/boot/dts/imx7d-sdb.dts
> >>> @@ -591,7 +591,7 @@
> >>>  		pinctrl_usdhc1: usdhc1grp {
> >>>  			fsl,pins = <
> >>>  				MX7D_PAD_SD1_CMD__SD1_CMD		0x59
> >>> -				MX7D_PAD_SD1_CLK__SD1_CLK		0x19
> >>> +				MX7D_PAD_SD1_CLK__SD1_CLK		0x09
> >>>  				MX7D_PAD_SD1_DATA0__SD1_DATA0		0x59
> >>>  				MX7D_PAD_SD1_DATA1__SD1_DATA1		0x59
> >>>  				MX7D_PAD_SD1_DATA2__SD1_DATA2		0x59
> >>> @@ -605,7 +605,7 @@
> >>>  		pinctrl_usdhc2: usdhc2grp {
> >>>  			fsl,pins = <
> >>>  				MX7D_PAD_SD2_CMD__SD2_CMD		0x59
> >>> -				MX7D_PAD_SD2_CLK__SD2_CLK		0x19
> >>> +				MX7D_PAD_SD2_CLK__SD2_CLK		0x09
> >>>  				MX7D_PAD_SD2_DATA0__SD2_DATA0		0x59
> >>>  				MX7D_PAD_SD2_DATA1__SD2_DATA1		0x59
> >>>  				MX7D_PAD_SD2_DATA2__SD2_DATA2		0x59
> >>> @@ -616,7 +616,7 @@
> >>>  		pinctrl_usdhc2_100mhz: usdhc2grp_100mhz {
> >>>  			fsl,pins = <
> >>>  				MX7D_PAD_SD2_CMD__SD2_CMD		0x5a
> >>> -				MX7D_PAD_SD2_CLK__SD2_CLK		0x1a
> >>> +				MX7D_PAD_SD2_CLK__SD2_CLK		0x0a
> >>>  				MX7D_PAD_SD2_DATA0__SD2_DATA0		0x5a
> >>>  				MX7D_PAD_SD2_DATA1__SD2_DATA1		0x5a
> >>>  				MX7D_PAD_SD2_DATA2__SD2_DATA2		0x5a
> >>> @@ -627,7 +627,7 @@
> >>>  		pinctrl_usdhc2_200mhz: usdhc2grp_200mhz {
> >>>  			fsl,pins = <
> >>>  				MX7D_PAD_SD2_CMD__SD2_CMD		0x5b
> >>> -				MX7D_PAD_SD2_CLK__SD2_CLK		0x1b
> >>> +				MX7D_PAD_SD2_CLK__SD2_CLK		0x0b
> >>>  				MX7D_PAD_SD2_DATA0__SD2_DATA0		0x5b
> >>>  				MX7D_PAD_SD2_DATA1__SD2_DATA1		0x5b
> >>>  				MX7D_PAD_SD2_DATA2__SD2_DATA2		0x5b
> >>> @@ -639,7 +639,7 @@
> >>>  		pinctrl_usdhc3: usdhc3grp {
> >>>  			fsl,pins = <
> >>>  				MX7D_PAD_SD3_CMD__SD3_CMD		0x59
> >>> -				MX7D_PAD_SD3_CLK__SD3_CLK		0x19
> >>> +				MX7D_PAD_SD3_CLK__SD3_CLK		0x09
> >>>  				MX7D_PAD_SD3_DATA0__SD3_DATA0		0x59
> >>>  				MX7D_PAD_SD3_DATA1__SD3_DATA1		0x59
> >>>  				MX7D_PAD_SD3_DATA2__SD3_DATA2		0x59
> >>> @@ -655,7 +655,7 @@
> >>>  		pinctrl_usdhc3_100mhz: usdhc3grp_100mhz {
> >>>  			fsl,pins = <
> >>>  				MX7D_PAD_SD3_CMD__SD3_CMD		0x5a
> >>> -				MX7D_PAD_SD3_CLK__SD3_CLK		0x1a
> >>> +				MX7D_PAD_SD3_CLK__SD3_CLK		0x0a
> >>>  				MX7D_PAD_SD3_DATA0__SD3_DATA0		0x5a
> >>>  				MX7D_PAD_SD3_DATA1__SD3_DATA1		0x5a
> >>>  				MX7D_PAD_SD3_DATA2__SD3_DATA2		0x5a
> >>> @@ -671,7 +671,7 @@
> >>>  		pinctrl_usdhc3_200mhz: usdhc3grp_200mhz {
> >>>  			fsl,pins = <
> >>>  				MX7D_PAD_SD3_CMD__SD3_CMD		0x5b
> >>> -				MX7D_PAD_SD3_CLK__SD3_CLK		0x1b
> >>> +				MX7D_PAD_SD3_CLK__SD3_CLK		0x0b
> >>>  				MX7D_PAD_SD3_DATA0__SD3_DATA0		0x5b
> >>>  				MX7D_PAD_SD3_DATA1__SD3_DATA1		0x5b
> >>>  				MX7D_PAD_SD3_DATA2__SD3_DATA2		0x5b
> >>> --
> >>> 2.7.4
> >>>
> >>>
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