[PATCH RFC 1/2] ARM: imx6qdl: provide pinctrl configurations for DAT3 pull-down

Stephen Warren swarren at wwwdotorg.org
Mon Oct 7 22:52:40 EDT 2013


On 10/07/2013 07:54 PM, Shawn Guo wrote:
> On Mon, Oct 07, 2013 at 07:03:57PM +0100, Russell King - ARM Linux wrote:
>> On Mon, Oct 07, 2013 at 01:53:43PM +0800, Shawn Guo wrote:
>>> I think we can redefine only pad DAT3 in pinctrl_usdhc1_1_dat3cd, and
>>> overwrite the DAT3 configuration in pinctrl_usdhc1_1 to save the
>>> redundant data of other pads, something like the following.
>>>
>>> pinctrl_usdhc1_1_dat3cd: usdhc1grp-3 {
>>> 	fsl,pins = <
>>> 		MX6QDL_PAD_SD1_DAT3__SD1_DATA3 0x13059
>>> 	>;
>>> };
>>>
>>> &usdhc1 {
>>> 	pinctrl-names = "default";
>>> 	pinctrl-0 = <&pinctrl_usdhc1_1 &pinctrl_usdhc1_1_dat3cd>;
>>> 	...
>>> 	status = "okay";
>>> };
>>
>> Are you sure that this will always be the case?  This would assume that
>> the pinctrl entries are always processed sequentially.
> 
> That will always be the case per my understanding.  Otherwise, I would
> be so surprised.  Are you seeing any case that the entries are not
> processed sequentially?

Given the way the Linux code currently works, I think that will
currently happen in practice. However, there's nothing in the pinctrl DT
binding documentation that guarantees (or even mentions) such semantics.



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