[PATCH v9 2/3] dt-bindings: pinctrl: mt8195: Add mediatek,drive-strength-adv property

From: Tinghan Shen <tinghan.shen@mediatek.com>
To: Rob Herring <robh+dt@kernel.org>,
	Linus Walleij <linus.walleij@linaro.org>,
	Matthias Brugger <matthias.bgg@gmail.com>,
	AngeloGioacchino Del Regno 
	<angelogioacchino.delregno@collabora.com>,
	"Tinghan Shen" <tinghan.shen@mediatek.com>,
	Paolo Bonzini <pbonzini@redhat.com>,
	"Sean Christopherson" <seanjc@google.com>,
	<maciej.szmigiero@oracle.com>,
	"David Matlack" <dmatlack@google.com>,
	Jing Zhang <jingzhangos@google.com>,
	"Marc Zyngier" <maz@kernel.org>,
	Bartosz Golaszewski <bgolaszewski@baylibre.com>,
	Sean Wang <sean.wang@mediatek.com>
Cc: <devicetree@vger.kernel.org>, <linux-kernel@vger.kernel.org>,
	<linux-gpio@vger.kernel.org>,
	<linux-arm-kernel@lists.infradead.org>,
	<linux-mediatek@lists.infradead.org>,
	<Project_Global_Chrome_Upstream_Group@mediatek.com>,
	<ryder.lee@kernel.org>, <wenst@chromium.org>,
	<chunfeng.yun@mediatek.com>
Subject: [PATCH v9 2/3] dt-bindings: pinctrl: mt8195: Add mediatek,drive-strength-adv property
Date: Wed, 12 Jan 2022 19:47:23 +0800	[thread overview]
Message-ID: <20220112114724.1953-3-tinghan.shen@mediatek.com> (raw)
In-Reply-To: <20220112114724.1953-1-tinghan.shen@mediatek.com>

Extend driving support for I2C pins on SoC mt8195.
This property is already documented in mediatek,mt8183-pinctrl.yaml.

Signed-off-by: Tinghan Shen <tinghan.shen@mediatek.com>
Reviewed-by: Rob Herring <robh@kernel.org>
---
 .../bindings/pinctrl/pinctrl-mt8195.yaml      | 35 +++++++++++++++++++
 1 file changed, 35 insertions(+)

diff --git a/Documentation/devicetree/bindings/pinctrl/pinctrl-mt8195.yaml b/Documentation/devicetree/bindings/pinctrl/pinctrl-mt8195.yaml
index 328ea59c5466..4db4899af6b1 100644
--- a/Documentation/devicetree/bindings/pinctrl/pinctrl-mt8195.yaml
+++ b/Documentation/devicetree/bindings/pinctrl/pinctrl-mt8195.yaml
@@ -98,6 +98,32 @@ patternProperties:
           drive-strength:
             enum: [2, 4, 6, 8, 10, 12, 14, 16]
 
+          mediatek,drive-strength-adv:
+            description: |
+              Describe the specific driving setup property.
+              For I2C pins, the existing generic driving setup can only support
+              2/4/6/8/10/12/14/16mA driving. But in specific driving setup, they
+              can support 0.125/0.25/0.5/1mA adjustment. If we enable specific
+              driving setup, the existing generic setup will be disabled.
+              The specific driving setup is controlled by E1E0EN.
+              When E1=0/E0=0, the strength is 0.125mA.
+              When E1=0/E0=1, the strength is 0.25mA.
+              When E1=1/E0=0, the strength is 0.5mA.
+              When E1=1/E0=1, the strength is 1mA.
+              EN is used to enable or disable the specific driving setup.
+              Valid arguments are described as below:
+              0: (E1, E0, EN) = (0, 0, 0)
+              1: (E1, E0, EN) = (0, 0, 1)
+              2: (E1, E0, EN) = (0, 1, 0)
+              3: (E1, E0, EN) = (0, 1, 1)
+              4: (E1, E0, EN) = (1, 0, 0)
+              5: (E1, E0, EN) = (1, 0, 1)
+              6: (E1, E0, EN) = (1, 1, 0)
+              7: (E1, E0, EN) = (1, 1, 1)
+              So the valid arguments are from 0 to 7.
+            $ref: /schemas/types.yaml#/definitions/uint32
+            enum: [0, 1, 2, 3, 4, 5, 6, 7]
+
           bias-pull-down:
             description: |
               For pull down type is normal, it don't need add RSEL & R1R0 define
@@ -268,4 +294,13 @@ examples:
           bias-pull-down;
         };
       };
+
+      i2c0-pins {
+        pins {
+          pinmux = <PINMUX_GPIO8__FUNC_SDA0>,
+                   <PINMUX_GPIO9__FUNC_SCL0>;
+          bias-disable;
+          mediatek,drive-strength-adv = <7>;
+        };
+      };
     };
-- 
2.18.0

