Subject: [PATCH 3/3] Addition of binding for firmware signals on peach-pi

From: [email-masked] (Martyn Welch)
Date: Wed, 02 Dec 2015 09:36:05 +0000

On 01/12/15 23:51, Krzysztof Kozlowski wrote:
> On 02.12.2015 04:12, Martyn Welch wrote:
>> The peach pi has a GPIO connected to the firmware write protect, developer
>> mode and recovery mode lines. This patch adds the required nodes to the
>> device tree to configure the pinmuxing and allow these to be read from
>> user space.
>>
>> Cc: Rob Herring <[email-masked]>
>> Cc: Pawel Moll <[email-masked]>
>> Cc: Mark Rutland <[email-masked]>
>> Cc: Ian Campbell <[email-masked]>
>> Cc: Kumar Gala <[email-masked]>
>> Cc: Russell King <[email-masked]>
>> Cc: Kukjin Kim <[email-masked]>
>> Cc: Krzysztof Kozlowski <[email-masked]>
>> Cc: devicetree at vger.kernel.org
>> Cc: linux-arm-kernel at lists.infradead.org
>> Cc: linux-samsung-soc at vger.kernel.org
>> Signed-off-by: Martyn Welch <[email-masked]>
>> ---
>>   arch/arm/boot/dts/exynos5800-peach-pi.dts | 40 +++++++++++++++++++++++++++++++
>>   1 file changed, 40 insertions(+)
>
> Hi,
>
> Thanks for the patch.
>
> Few points from my side:
> 1. Please add a prefix to the subject: "ARM: dts:".
>

Ok, sorry.

> 2. There is no need of such huge CC-list in the body of commit. This
> CC-list comes from get_maintainer so there is no benefit of duplicating
> it here. The CC is usually used to notify other people who might be
> interested but get_maintainer does not point them.
>

Ok, yes these were pulled from get_maintainer.

> 3. I received only this third patch. I did not receive cover letter
> explaining possible dependencies so I am not sure how to deal with the
> patch. It looks like there are no dependencies... but maybe there are?
> Is this is a new binding or no? Please provide a cover letter (if it
> exists already be sure to send it to all interested parties) or send
> entire patchset so the big picture could be seen.
>

I'll make sure I do that next time.

The cover letter read:

Some Chromebooks have gpio attached to signals used to cause the 
firmware to enter alternative modes of operation and/or control other 
device characteristics (such as write protection on flash devices). This 
patch adds a driver that exposes a read-only interface to allow these 
signals to be read from user space.

In addition this patch series provides the required bindings for this to 
the peach-pi Chromebook.

This is a new binding, but the driver is based on functionality in the 
kernel shipped on Chromebooks. The binding has been modified based on 
the form of existing bindings in the mainline kernel.

Does that help?

Martyn

> The patch itself looks good but I'll wait with a review tag for #3.
>
> Best regards,
> Krzysztof
>
>
>>
>> diff --git a/arch/arm/boot/dts/exynos5800-peach-pi.dts b/arch/arm/boot/dts/exynos5800-peach-pi.dts
>> index 49a4f43..485c18f 100644
>> --- a/arch/arm/boot/dts/exynos5800-peach-pi.dts
>> +++ b/arch/arm/boot/dts/exynos5800-peach-pi.dts
>> @@ -53,6 +53,25 @@
>>   		};
>>   	};
>>
>> +	chromeos-firmware {
>> +		compatible = "google,gpio-firmware";
>> +
>> +		pinctrl-names = "default";
>> +		pinctrl-0 = <&wp_gpio &dev_mode &rec_mode>;
>> +
>> +		write-protect {
>> +			gpios = <&gpx3 0 GPIO_ACTIVE_LOW>;
>> +		};
>> +
>> +		developer-switch {
>> +			gpios = <&gpx1 3 GPIO_ACTIVE_HIGH>;
>> +		};
>> +
>> +		recovery-switch {
>> +			gpios = <&gpx0 7 GPIO_ACTIVE_LOW>;
>> +		};
>> +	};
>> +
>>   	gpio-keys {
>>   		compatible = "gpio-keys";
>>
>> @@ -731,6 +750,13 @@
>>   		samsung,pin-val = <0>;
>>   	};
>>
>> +	rec_mode: rec-mode {
>> +		samsung,pins = "gpx0-7";
>> +		samsung,pin-function = <0>;
>> +		samsung,pin-pud = <0>;
>> +		samsung,pin-drv = <0>;
>> +	};
>> +
>>   	tpm_irq: tpm-irq {
>>   		samsung,pins = "gpx1-0";
>>   		samsung,pin-function = <0>;
>> @@ -752,6 +778,13 @@
>>   		samsung,pin-drv = <0>;
>>   	};
>>
>> +	dev_mode: dev-mode {
>> +		samsung,pins = "gpx1-3";
>> +		samsung,pin-function = <0>;
>> +		samsung,pin-pud = <3>;
>> +		samsung,pin-drv = <0>;
>> +	};
>> +
>>   	ec_irq: ec-irq {
>>   		samsung,pins = "gpx1-5";
>>   		samsung,pin-function = <0>;
>> @@ -773,6 +806,13 @@
>>   		samsung,pin-drv = <0>;
>>   	};
>>
>> +	wp_gpio: wp_gpio {
>> +		samsung,pins = "gpx3-0";
>> +		samsung,pin-function = <0>;
>> +		samsung,pin-pud = <0>;
>> +		samsung,pin-drv = <0>;
>> +	};
>> +
>>   	max77802_irq: max77802-irq {
>>   		samsung,pins = "gpx3-1";
>>   		samsung,pin-function = <0>;
>>
>