We came to a point where we sometimes we support a few dozen boards
with a given SoC. Sometimes, we have to take into consideration
configurations which deviate rather significatly from the reference
or most common designs. In the context of pinctrl, this often comes
down to wildly different pin configurations. While pins, function and
drive-strength are easily overridable, the (mostly) boolean properties
associated with setting bias, aren't. This wouldn't be much of a
problem if they didn't differ between boards so often, preventing us
from having a "nice" baseline setup without inevitably having to go
with an ugly /delete-property/. Introduce bias-type, a bias-type-
specific property and clone the pinconf-generic type enum into
dt-bindings to allow for setting the bias in an easily overridable
manner such as:
// SoC DT
i2c0_pin: i2c0-pin-state {
pins = "gpio10";
function = "gpio";
bias-type = <BIAS_PULL_UP>;
};
// Deviant board DT
&i2c0_pin {
bias-type = <BIAS_HIGH_IMPEDANCE>;
};
Signed-off-by: Konrad Dybcio <konrad.dybcio@xxxxxxxxxx>
---
.../bindings/pinctrl/pincfg-node.yaml | 4 ++
include/dt-bindings/pinctrl/pinconf-generic.h | 40 +++++++++++++++++++
2 files changed, 44 insertions(+)
create mode 100644 include/dt-bindings/pinctrl/pinconf-generic.h
diff --git a/Documentation/devicetree/bindings/pinctrl/pincfg-node.yaml b/Documentation/devicetree/bindings/pinctrl/pincfg-node.yaml
index be81ed22a036..d4ea563d283e 100644
--- a/Documentation/devicetree/bindings/pinctrl/pincfg-node.yaml
+++ b/Documentation/devicetree/bindings/pinctrl/pincfg-node.yaml
@@ -51,6 +51,10 @@ properties:
description: use pin-default pull state. Takes as optional argument on
hardware supporting it the pull strength in Ohm.
+ bias-type:
+ $ref: /schemas/types.yaml#/definitions/uint32
+ description: Use the specified bias type.
+
drive-push-pull:
oneOf:
- type: boolean
diff --git a/include/dt-bindings/pinctrl/pinconf-generic.h b/include/dt-bindings/pinctrl/pinconf-generic.h
new file mode 100644
index 000000000000..7d9c7d8f9105
--- /dev/null
+++ b/include/dt-bindings/pinctrl/pinconf-generic.h
@@ -0,0 +1,40 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright (C) 2011 ST-Ericsson SA
+ * Written on behalf of Linaro for ST-Ericsson
+ *
+ * Author: Linus Walleij <linus.walleij@xxxxxxxxxx>
+ */
+
+#ifndef _DT_BINDINGS_PINCTRL_PINCONF_GENERIC_H
+#define _DT_BINDINGS_PINCTRL_PINCONF_GENERIC_H
+
+#define BIAS_BUS_HOLD 0
+#define BIAS_DISABLE 1
+#define BIAS_HIGH_IMPEDANCE 2
+#define BIAS_PULL_DOWN 3
+#define BIAS_PULL_PIN_DEFAULT 4
+#define BIAS_PULL_UP 5
+#define DRIVE_OPEN_DRAIN 6
+#define DRIVE_OPEN_SOURCE 7
+#define DRIVE_PUSH_PULL 8
+#define DRIVE_STRENGTH 9
+#define DRIVE_STRENGTH_UA 10
+#define INPUT_DEBOUNCE 11
+#define INPUT_ENABLE 12
+#define INPUT_SCHMITT 13
+#define INPUT_SCHMITT_ENABLE 14
+#define MODE_LOW_POWER 15
+#define MODE_PWM 16
+#define OUTPUT 17
+#define OUTPUT_ENABLE 18
+#define OUTPUT_IMPEDANCE_OHMS 19
+#define PERSIST_STATE 20
+#define POWER_SOURCE 21
+#define SKEW_DELAY 22
+#define SLEEP_HARDWARE_STATE 23
+#define SLEW_RATE 24
+#define PIN_CONFIG_END 0x7F
+#define PIN_CONFIG_MAX 0xFF
+
+#endif
--
2.39.1
