linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
* [PATCH] dt-bindings: pinctrl: mt8195: Use real world values for drive-strength arguments
@ 2021-07-26 11:19 Chen-Yu Tsai
  2021-07-29 23:37 ` Rob Herring
  2021-08-11  9:05 ` Linus Walleij
  0 siblings, 2 replies; 3+ messages in thread
From: Chen-Yu Tsai @ 2021-07-26 11:19 UTC (permalink / raw)
  To: Linus Walleij, Rob Herring, Matthias Brugger, Sean Wang, Zhiyong Tao
  Cc: Chen-Yu Tsai, linux-gpio, devicetree, linux-mediatek,
	linux-arm-kernel, linux-kernel

The original binding submission for MT8195 pinctrl described the
possible drive strength values in micro-amps in its description, but
then proceeded to list register values in its device tree binding
constraints.

However, the macros used with the Mediatek pinctrl bindings directly
specify the drive strength in micro-amps, instead of hardware register
values. The current driver implementation in Linux does convert the
value from micro-amps to hardware register values. This implementation
is also used with MT7622 and MT8183, which use real world values in
their device trees.

Given the above, it was likely an oversight to use the raw register
values in the binding. Correct the values in the binding. Also drop
the description since the binding combined with its parent,
pinctrl/pincfg.yaml, the binding is now self-describing.

Fixes: 7f7663899d94 ("dt-bindings: pinctrl: mt8195: add pinctrl file and binding document")
Signed-off-by: Chen-Yu Tsai <wenst@chromium.org>
---
 .../devicetree/bindings/pinctrl/pinctrl-mt8195.yaml          | 5 +----
 1 file changed, 1 insertion(+), 4 deletions(-)

diff --git a/Documentation/devicetree/bindings/pinctrl/pinctrl-mt8195.yaml b/Documentation/devicetree/bindings/pinctrl/pinctrl-mt8195.yaml
index 2f12ec59eee5..e17a399e0904 100644
--- a/Documentation/devicetree/bindings/pinctrl/pinctrl-mt8195.yaml
+++ b/Documentation/devicetree/bindings/pinctrl/pinctrl-mt8195.yaml
@@ -80,10 +80,7 @@ patternProperties:
           as macros in dt-bindings/pinctrl/<soc>-pinfunc.h directly.
 
       drive-strength:
-        description: |
-          It can support some arguments which is from 0 to 7. It can only support
-          2/4/6/8/10/12/14/16mA in mt8195.
-        enum: [0, 1, 2, 3, 4, 5, 6, 7]
+        enum: [2, 4, 6, 8, 10, 12, 14, 16]
 
       bias-pull-down: true
 
-- 
2.32.0.432.gabb21c7263-goog


^ permalink raw reply	[flat|nested] 3+ messages in thread

* Re: [PATCH] dt-bindings: pinctrl: mt8195: Use real world values for drive-strength arguments
  2021-07-26 11:19 [PATCH] dt-bindings: pinctrl: mt8195: Use real world values for drive-strength arguments Chen-Yu Tsai
@ 2021-07-29 23:37 ` Rob Herring
  2021-08-11  9:05 ` Linus Walleij
  1 sibling, 0 replies; 3+ messages in thread
From: Rob Herring @ 2021-07-29 23:37 UTC (permalink / raw)
  To: Chen-Yu Tsai
  Cc: linux-mediatek, Matthias Brugger, Sean Wang, linux-arm-kernel,
	linux-gpio, devicetree, Rob Herring, linux-kernel, Zhiyong Tao,
	Linus Walleij

On Mon, 26 Jul 2021 19:19:41 +0800, Chen-Yu Tsai wrote:
> The original binding submission for MT8195 pinctrl described the
> possible drive strength values in micro-amps in its description, but
> then proceeded to list register values in its device tree binding
> constraints.
> 
> However, the macros used with the Mediatek pinctrl bindings directly
> specify the drive strength in micro-amps, instead of hardware register
> values. The current driver implementation in Linux does convert the
> value from micro-amps to hardware register values. This implementation
> is also used with MT7622 and MT8183, which use real world values in
> their device trees.
> 
> Given the above, it was likely an oversight to use the raw register
> values in the binding. Correct the values in the binding. Also drop
> the description since the binding combined with its parent,
> pinctrl/pincfg.yaml, the binding is now self-describing.
> 
> Fixes: 7f7663899d94 ("dt-bindings: pinctrl: mt8195: add pinctrl file and binding document")
> Signed-off-by: Chen-Yu Tsai <wenst@chromium.org>
> ---
>  .../devicetree/bindings/pinctrl/pinctrl-mt8195.yaml          | 5 +----
>  1 file changed, 1 insertion(+), 4 deletions(-)
> 

Acked-by: Rob Herring <robh@kernel.org>

^ permalink raw reply	[flat|nested] 3+ messages in thread

* Re: [PATCH] dt-bindings: pinctrl: mt8195: Use real world values for drive-strength arguments
  2021-07-26 11:19 [PATCH] dt-bindings: pinctrl: mt8195: Use real world values for drive-strength arguments Chen-Yu Tsai
  2021-07-29 23:37 ` Rob Herring
@ 2021-08-11  9:05 ` Linus Walleij
  1 sibling, 0 replies; 3+ messages in thread
From: Linus Walleij @ 2021-08-11  9:05 UTC (permalink / raw)
  To: Chen-Yu Tsai
  Cc: Rob Herring, Matthias Brugger, Sean Wang, Zhiyong Tao,
	open list:GPIO SUBSYSTEM,
	open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS,
	moderated list:ARM/Mediatek SoC support, Linux ARM, linux-kernel

On Mon, Jul 26, 2021 at 1:19 PM Chen-Yu Tsai <wenst@chromium.org> wrote:

> The original binding submission for MT8195 pinctrl described the
> possible drive strength values in micro-amps in its description, but
> then proceeded to list register values in its device tree binding
> constraints.
>
> However, the macros used with the Mediatek pinctrl bindings directly
> specify the drive strength in micro-amps, instead of hardware register
> values. The current driver implementation in Linux does convert the
> value from micro-amps to hardware register values. This implementation
> is also used with MT7622 and MT8183, which use real world values in
> their device trees.
>
> Given the above, it was likely an oversight to use the raw register
> values in the binding. Correct the values in the binding. Also drop
> the description since the binding combined with its parent,
> pinctrl/pincfg.yaml, the binding is now self-describing.
>
> Fixes: 7f7663899d94 ("dt-bindings: pinctrl: mt8195: add pinctrl file and binding document")
> Signed-off-by: Chen-Yu Tsai <wenst@chromium.org>

Patch applied.

Yours,
Linus Walleij

^ permalink raw reply	[flat|nested] 3+ messages in thread

end of thread, other threads:[~2021-08-11  9:05 UTC | newest]

Thread overview: 3+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2021-07-26 11:19 [PATCH] dt-bindings: pinctrl: mt8195: Use real world values for drive-strength arguments Chen-Yu Tsai
2021-07-29 23:37 ` Rob Herring
2021-08-11  9:05 ` Linus Walleij

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).