Re: [RFC PATCH 05/10] dt-bindings: pwm: Add bindings for PWM function in Netronix EC
From: Andreas Kemnade <andreas@kemnade.info>
Date: 2020-06-21 19:23:08
Also in:
linux-pwm, linux-rtc, lkml
On Sun, 21 Jun 2020 00:42:16 +0200 Jonathan Neuschäfer [off-list ref] wrote:
The Netronix embedded controller as found in Kobo Aura and Tolino Shine supports one PWM channel, which is used to control the frontlight brightness on these devices. Known problems: - `make dt_binding_check` shows the following warnings: Documentation/devicetree/bindings/mfd/netronix,ntxec.example.dts:49.17-42: Warning (pwms_property): /example-0/backlight:pwms: cell 2 is not a phandle reference Documentation/devicetree/bindings/mfd/netronix,ntxec.example.dts:49.17-42: Warning (pwms_property): /example-0/backlight:pwms: Could not get phandle node for (cell 2)
In the tolino sources in ./drivers/misc/ntx-misc.c I find this line
if(4==gptHWCFG->m_val.bFL_PWM) {
No idea what it does but I would expect to have a kind of translation to
a dt property?
quoted hunk ↗ jump to hunk
Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net> --- .../bindings/mfd/netronix,ntxec.yaml | 13 ++++++++ .../bindings/pwm/netronix,ntxec-pwm.yaml | 33 +++++++++++++++++++ 2 files changed, 46 insertions(+) create mode 100644 Documentation/devicetree/bindings/pwm/netronix,ntxec-pwm.yamldiff --git a/Documentation/devicetree/bindings/mfd/netronix,ntxec.yaml b/Documentation/devicetree/bindings/mfd/netronix,ntxec.yaml index 596df460f98eb..6562c41c5a9a9 100644 --- a/Documentation/devicetree/bindings/mfd/netronix,ntxec.yaml +++ b/Documentation/devicetree/bindings/mfd/netronix,ntxec.yaml@@ -31,6 +31,9 @@ properties: description: The EC can signal interrupts via a GPIO line + pwm: + $ref: ../pwm/netronix,ntxec-pwm.yaml + required: - compatible - reg@@ -53,5 +56,15 @@ examples: interrupts = <11 IRQ_TYPE_EDGE_FALLING>; interrupt-controller; #interrupt-cells = <1>; + + ec_pwm: pwm { + compatible = "netronix,ntxec-pwm"; + #pwm-cells = <1>;
shouldn't that be 2?
+ };
};
};
+
+ backlight {
+ compatible = "pwm-backlight";
+ pwms = <&ec_pwm 0 50000>;since you have 2 values after the &ec_pwm
quoted hunk ↗ jump to hunk
+ };diff --git a/Documentation/devicetree/bindings/pwm/netronix,ntxec-pwm.yaml b/Documentation/devicetree/bindings/pwm/netronix,ntxec-pwm.yaml new file mode 100644 index 0000000000000..1dc1b1aba081c --- /dev/null +++ b/Documentation/devicetree/bindings/pwm/netronix,ntxec-pwm.yaml@@ -0,0 +1,33 @@ +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/pwm/netronix,ntxec-pwm.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: PWM functionality in Netronix embedded controller + +maintainers: + - Jonathan Neuschäfer <j.neuschaefer@gmx.net> + +description: | + See also Documentation/devicetree/bindings/mfd/netronix,ntxec.yaml + + The Netronix EC contains PWM functionality, which is usually used to drive + the backlight LED. + + The following PWM channels are supported: + - 0: The PWM channel controlled by registers 0xa1-0xa7 + +allOf: + - $ref: pwm.yaml# + +properties: + compatible: + const: netronix,ntxec-pwm + + "#pwm-cells": + const: 1
shouln't that be 2?
+ +required: + - compatible + - "#pwm-cells" -- 2.27.0
Regards, Andreas