* Tony Lindgren <t...@atomide.com> [151201 17:23]:
> * Matthijs van Duin <matthijsvand...@gmail.com> [151201 17:15]:
> > On 2 December 2015 at 01:46, Tony Lindgren <t...@atomide.com> wrote:
> > > Ouch. We should probably have separate PIN_INPUT_3V3 and PIN_OUTPUT_3V3
> > > dts macros that ensure that?
> > 
> > Can't we just keep bit 18 out of the function mask? The bootloader
> > should already have made sure all pins have bit 18 set (and bit 19 set
> > to correct values after ROM mucked them up, see advisory 2.1.88), so
> > all that needs to be done is avoid touching them.
> 
> Sounds good to me. And people who really want to override the mask can
> do it in the board specifc dts file.
> 
> > Are the power savings from disabling unnecessary inputs significant
> > enough to spend any headache on it?
> 
> Only for some battery powered devices, not in this case for sure.

And here's an updated version of this patch.

Regards,

Tony

8< ----------------------------
From: Tony Lindgren <t...@atomide.com>
Date: Tue, 1 Dec 2015 15:04:38 -0800
Subject: [PATCH] ARM: dts: Fix dm814x pinctrl address and mask

Otherwise pinctrl won't work. Because of silicon errata for some dm814x
versions, let's also keep bit 18 out of the function-mask and rely on
the bootloader configuration for bit 18  as suggested by
Matthijs van Duin <matthijsvand...@gmail.com>.

Devices with that need to use bit 18 can override the function-mask in
the board specific dts file if really needed.

Signed-off-by: Tony Lindgren <t...@atomide.com>

--- a/arch/arm/boot/dts/dm814x.dtsi
+++ b/arch/arm/boot/dts/dm814x.dtsi
@@ -205,13 +205,21 @@
                                        };
                                };
 
+                               /*
+                                * Note that silicon revision 2.1 and older
+                                * require input enabled (bit 18 set) for all
+                                * 3.3V I/Os to avoid cumulative hardware 
damage.
+                                * For more info, see errata advisory 2.1.87.
+                                * We leave bit 18 out of function-mask and rely
+                                * on the bootloader for it.
+                                */
                                pincntl: pinmux@800 {
                                        compatible = "pinctrl-single";
-                                       reg = <0x800 0xc38>;
+                                       reg = <0x800 0x438>;
                                        #address-cells = <1>;
                                        #size-cells = <0>;
                                        pinctrl-single,register-width = <32>;
-                                       pinctrl-single,function-mask = 
<0x300ff>;
+                                       pinctrl-single,function-mask = 
<0x307ff>;
                                };
                        };
 
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