Re: [PATCH v2] Extend pca9532 device tree support

From: Jacek Anaszewski
Date: Thu Apr 06 2017 - 15:01:09 EST


Hi Pavel,

On 04/06/2017 05:50 PM, Pavel Machek wrote:
> Hi!
>
>>> diff --git a/Documentation/devicetree/bindings/leds/leds-pca9532.txt b/Documentation/devicetree/bindings/leds/leds-pca9532.txt
>>> index 198f3ba..8374075 100644
>>> --- a/Documentation/devicetree/bindings/leds/leds-pca9532.txt
>>> +++ b/Documentation/devicetree/bindings/leds/leds-pca9532.txt
>>> @@ -17,6 +17,8 @@ Optional sub-node properties:
>>> - label: see Documentation/devicetree/bindings/leds/common.txt
>>> - type: Output configuration, see dt-bindings/leds/leds-pca9532.h (default NONE)
>>> - linux,default-trigger: see Documentation/devicetree/bindings/leds/common.txt
>>> + - default-state: see Documentation/devicetree/bindings/leds/common.txt
>>> + This property is only valid for sub-nodes of type <PCA9532_TYPE_LED>.
>>>
>>> Example:
>>> #include <dt-bindings/leds/leds-pca9532.h>
>>> @@ -33,6 +35,14 @@ Example:
>>> label = "pca:green:power";
>>> type = <PCA9532_TYPE_LED>;
>>> };
>>> + kernel-booting {
>>> + type = <PCA9532_TYPE_LED>;
>>> + default-state = "on";
>>> + };
>>> + sys-stat {
>>> + type = <PCA9532_TYPE_LED>;
>>> + default-state = "keep"; // don't touch, was set by U-Boot
>>> + };
>>
>> Adjusted above indentation to match the preceding lines.
>
>>> @@ -475,6 +494,16 @@ pca9532_of_populate_pdata(struct device *dev, struct device_node *np)
>>> of_property_read_u32(child, "type", &pdata->leds[i].type);
>>> of_property_read_string(child, "linux,default-trigger",
>>> &pdata->leds[i].default_trigger);
>>> + if (!of_property_read_string(child, "default-state", &state)) {
>>> + if (!strcmp(state, "on"))
>>> + pdata->leds[i].state = PCA9532_ON;
>>> + else if (!strcmp(state, "keep"))
>>> + pdata->leds[i].state = PCA9532_KEEP;
>>> + else if (!strcmp(state, "pwm0"))
>>> + pdata->leds[i].state = PCA9532_PWM0;
>>> + else if (!strcmp(state, "pwm1"))
>>> + pdata->leds[i].state = PCA9532_PWM1;
>>> + }
>>> if (++i >= maxleds) {
>>> of_node_put(child);
>>> break;
>
> This seems to look for "pwm0" and "pwm1" strings, which do not seem to
> be documented.
>
> Plus... is it useful to have default-state? We already have default
> trigger. If we keep the value by default (on PC, we do something like
> that) this patch should not be neccessary?

Thanks for the heads-up. Dropping the patch for now.
I guess that pwm0/1 got propagated to v2 by an omission.

Regarding default-on: Felix, do you have any use case that require
default-on set to "keep"?

--
Best regards,
Jacek Anaszewski