Leela

On Fri, Jun 14, 2013 at 5:21 AM, Leela Krishna Amudala
<l.kris...@samsung.com> wrote:
> Here the GPIO pins added for sd0_bus1, sd0_bus4 and sd0_bus8 are correct
> Please look at the below example dwmmc node configured for 8bit bus width
>
> dwmmc0@12200000 {
>                 /*...*/
>                 pinctrl-names = "default";
>                 pinctrl-0 = <&sd0_clk &sd0_cmd &sd0_bus4 &sd0_bus8>;
>
>                 slot@0 {
>                         reg = <0>;
>                         bus-width = <8>;
>                 };
>         };
>
> In the above node we are specifying "&sd0_bus4 &sd0_bus8" in pinctrl-0
> Pinctrl driver will configure the respective gpio pins given in
> sd0_bus4 and sd0_bus8 nodes.
> (which are "gpc0-3", "gpc0-4", "gpc0-5", "gpc0-6", "gpc3-0", "gpc3-1",
> "gpc3-2", "gpc3-3")
>
> But if we make gpio entries for sd0_bus1, sd0_bus4 and sd0_bus8 like below
>
>                sd0_bus1: sd0-bus-width1 {
>                         samsung,pins = "gpc0-3";
>                         /*...*/
>                 };
>
>                 sd0_bus4: sd0-bus-width4 {
>                         samsung,pins = "gpc0-4", "gpc0-5", "gpc0-6";
>                         /*...*/
>                 };
>
>                 sd0_bus8: sd0-bus-width8 {
>                         samsung,pins = "gpc3-0", "gpc3-1", "gpc3-2", "gpc3-3";
>                         /*...*/
>                 };
>
> we have to make entries like below for dwmmc node to configure 8bit bus width.
> pinctrl-0 = <&sd0_clk &sd0_cmd &sd0_bus1 &sd0_bus4 &sd0_bus8>;
>
> or if we choose like below
>
>                 sd0_bus1: sd0-bus-width1 {
>                         samsung,pins = "gpc0-3";
>                         /*...*/
>                 };
>
>                 sd0_bus4: sd0-bus-width4 {
>                         samsung,pins = "gpc0-3", "gpc0-4", "gpc0-5", "gpc0-6";
>                         /*...*/
>                 };
>
>                 sd0_bus8: sd0-bus-width8 {
>                         samsung,pins = "gpc0-3", "gpc0-4", "gpc0-5",
> "gpc0-6", "gpc3-0", "gpc3-1", "gpc3-2", "gpc3-3";
>                         /*...*/
>                 };
>
> Then specifying pinctrl-0 = <&sd0_clk &sd0_cmd &sd0_bus8>; is enough
>
> Because all the other boards have the similar kind of nodes specified
> in their DT files, I followed the same convention.

Right.  I think what we're saying here is that all the other boards
are wrong and ought to be fixed in a separate patch.  ...following
existing convention is often a good thing to do, but in this case
we're asking to break convention and do the correct thing.

I think Tomasz expressed a desire to use the syntax:
    pinctrl-0 = <&sd0_clk &sd0_cmd &sd0_bus1 &sd0_bus4 &sd0_bus8>;

-Doug
--
To unsubscribe from this list: send the line "unsubscribe linux-samsung-soc" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Reply via email to