[PATCH 3/3] dt-bindings: net: nfc: s3fwrn5: fix polarity of "enable" line of NFC chip

Dmitry Torokhov dmitry.torokhov at gmail.com
Wed Sep 28 18:15:57 PDT 2022


According to s3fwrn5 driver code the "enable" GPIO line is driven "high"
when chip is not in use (mode is S3FWRN5_MODE_COLD), and is driven "low"
when chip is in use.

s3fwrn5_phy_power_ctrl():

	...
	gpio_set_value(phy->gpio_en, 1);
	...
	if (mode != S3FWRN5_MODE_COLD) {
		msleep(S3FWRN5_EN_WAIT_TIME);
		gpio_set_value(phy->gpio_en, 0);
		msleep(S3FWRN5_EN_WAIT_TIME);
	}

Therefore the line described by "en-gpios" property should be annotated
as "active low".

The wakeup gpio appears to have correct polarity (active high).

Signed-off-by: Dmitry Torokhov <dmitry.torokhov at gmail.com>
---
 .../devicetree/bindings/net/nfc/samsung,s3fwrn5.yaml          | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/Documentation/devicetree/bindings/net/nfc/samsung,s3fwrn5.yaml b/Documentation/devicetree/bindings/net/nfc/samsung,s3fwrn5.yaml
index 64995cbb0f97..78e3c13f1acb 100644
--- a/Documentation/devicetree/bindings/net/nfc/samsung,s3fwrn5.yaml
+++ b/Documentation/devicetree/bindings/net/nfc/samsung,s3fwrn5.yaml
@@ -81,7 +81,7 @@ examples:
             interrupt-parent = <&gpa1>;
             interrupts = <3 IRQ_TYPE_EDGE_RISING>;
 
-            en-gpios = <&gpf1 4 GPIO_ACTIVE_HIGH>;
+            en-gpios = <&gpf1 4 GPIO_ACTIVE_LOW>;
             wake-gpios = <&gpj0 2 GPIO_ACTIVE_HIGH>;
 
             clocks = <&rpmcc 20>;
@@ -93,7 +93,7 @@ examples:
         nfc {
             compatible = "samsung,s3fwrn82";
 
-            en-gpios = <&gpio 20 GPIO_ACTIVE_HIGH>;
+            en-gpios = <&gpio 20 GPIO_ACTIVE_LOW>;
             wake-gpios = <&gpio 16 GPIO_ACTIVE_HIGH>;
 
         };
-- 
2.38.0.rc1.362.ged0d419d3c-goog




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