[{"id":1769749,"web_url":"http://patchwork.ozlabs.org/comment/1769749/","msgid":"<6baeee56-480b-00b9-4c84-e65dc7c42301@gmail.com>","list_archive_url":null,"date":"2017-09-17T16:57:09","subject":"Re: [PATCH 1/2] ACPI: Document how to refer to LEDs from remote\n\tnodes","submitter":{"id":66885,"url":"http://patchwork.ozlabs.org/api/people/66885/","name":"Jacek Anaszewski","email":"jacek.anaszewski@gmail.com"},"content":"Hi Sakari,\n\nThanks for the patch.\n\nOn 09/15/2017 04:40 PM, Sakari Ailus wrote:\n> Document referring to LEDs from remote device nodes, such as from camera\n> sensors.\n> \n> Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>\n> ---\n>  Documentation/acpi/dsd/leds.txt | 94 +++++++++++++++++++++++++++++++++++++++++\n>  1 file changed, 94 insertions(+)\n>  create mode 100644 Documentation/acpi/dsd/leds.txt\n> \n> diff --git a/Documentation/acpi/dsd/leds.txt b/Documentation/acpi/dsd/leds.txt\n> new file mode 100644\n> index 000000000000..894c82274f53\n> --- /dev/null\n> +++ b/Documentation/acpi/dsd/leds.txt\n> @@ -0,0 +1,94 @@\n> +Describing and referring to LEDs in ACPI\n> +\n> +Individual LEDs are described by hierarchical data extension [6] nodes\n> +under the device node, the LED driver chip. The \"led\" property in the\n> +LED specific nodes tells the numerical ID of each individual LED. The\n> +\"led\" property is used here in a similar fashion as the \"reg\" property\n> +in DT. [3]\n> +\n> +Referring to LEDs in Device tree is documented in [4], in \"flash-leds\"\n> +property documentation. In short, LEDs are directly referred to by\n> +using phandles.\n> +\n> +While Device tree allows referring to any node in the tree[1], in ACPI\n> +references are limited to device nodes only [2]. For this reason using\n> +the same mechanism on ACPI is not possible.\n> +\n> +ACPI allows (as does DT) using integer arguments after the reference.\n> +A combination of the LED driver device reference and an integer\n> +argument, referring to the \"led\" property of the relevant LED, are\n> +use to individual LEDs.\n\ns/are use/is used/ ? (in a sense \"combination of ... and .. is used\")\n\ns/to individual/to describe individual/\n\n(or another verb, I'm not sure what exactly you intended it to be)\n\n The value of the LED property is a contract\n> +between the firmware and software, it uniquely identifies the LED\n> +driver outputs.\n> +\n> +An ASL example of a camera sensor device and a LED driver device for two\n> +LEDs. Objects not relevant for LEDs or the references to them have been\n> +omitted.\n> +\n> +\tDevice (LED)\n> +\t{\n> +\t\tName (_DSD, Package () {\n> +\t\t\tToUUID(\"dbb8e3e6-5886-4ba6-8795-1319f52a966b\"),\n> +\t\t\tPackage () {\n> +\t\t\t\tPackage () { \"led0\", LED0 },\n> +\t\t\t\tPackage () { \"led1\", LED1 },\n> +\t\t\t}\n> +\t\t})\n> +\t\tName (LED0, Package () {\n> +\t\t\tToUUID(\"daffd814-6eba-4d8c-8a91-bc9bbf4aa301\"),\n> +\t\t\tPackage () {\n> +\t\t\t\tPackage () { \"led\", 0 },\n> +\t\t\t\tPackage () { \"flash-max-microamp\", 1000000 },\n> +\t\t\t\tPackage () { \"flash-timeout-us\", 200000 },\n> +\t\t\t\tPackage () { \"led-max-microamp\", 100000 },\n> +\t\t\t\tPackage () { \"label\", \"led:salama\" },\n> +\t\t\t}\n> +\t\t})\n> +\t\tName (LED1, Package () {\n> +\t\t\tToUUID(\"daffd814-6eba-4d8c-8a91-bc9bbf4aa301\"),\n> +\t\t\tPackage () {\n> +\t\t\t\tPackage () { \"led\", 1 },\n> +\t\t\t\tPackage () { \"led-max-microamp\", 10000 },\n> +\t\t\t\tPackage () { \"label\", \"led:huomiovalo\" },\n> +\t\t\t}\n> +\t\t})\n> +\t}\n> +\n> +\tDevice (SEN)\n> +\t{\n> +\t\tName (_DSD, Package () {\n> +\t\t\tToUUID(\"daffd814-6eba-4d8c-8a91-bc9bbf4aa301\"),\n> +\t\t\tPackage () {\n> +\t\t\t\tPackage () {\n> +\t\t\t\t\t\"flash-leds\",\n> +\t\t\t\t\tPackage () { ^LED, 0, ^LED, 1 },\n> +\t\t\t\t}\n> +\t\t\t}\n> +\t\t})\n> +\t}\n> +\n> +where\n> +\n> +\tLED\tLED driver device\n> +\tLED0\tFirst LED\n> +\tLED1\tSecond LED\n> +\tSEN\tCamera sensor device (or another device the LED is\n> +\t\trelated to)\n> +\n> +[1] Device tree. <URL:http://www.devicetree.org>, referenced 2016-10-03.\n> +\n> +[2] Advanced Configuration and Power Interface Specification.\n> +    <URL:http://www.uefi.org/sites/default/files/resources/ACPI_6_1.pdf>,\n> +    referenced 2016-10-04.\n> +\n> +[3] Documentation/devicetree/bindings/leds/common.txt\n> +\n> +[4] Documentation/devicetree/bindings/media/video-interfaces.txt\n> +\n> +[5] Device Properties UUID For _DSD.\n> +    <URL:http://www.uefi.org/sites/default/files/resources/_DSD-device-properties-UUID.pdf>,\n> +    referenced 2016-10-04.\n> +\n> +[6] Hierarchical Data Extension UUID For _DSD.\n> +    <URL:http://www.uefi.org/sites/default/files/resources/_DSD-hierarchical-data-extension-UUID-v1.pdf>,\n> +    referenced 2016-10-04.\n>","headers":{"Return-Path":"<devicetree-owner@vger.kernel.org>","X-Original-To":"incoming-dt@patchwork.ozlabs.org","Delivered-To":"patchwork-incoming-dt@bilbo.ozlabs.org","Authentication-Results":["ozlabs.org;\n\tspf=none (mailfrom) smtp.mailfrom=vger.kernel.org\n\t(client-ip=209.132.180.67; helo=vger.kernel.org;\n\tenvelope-from=devicetree-owner@vger.kernel.org; receiver=<UNKNOWN>)","ozlabs.org;\n\tdkim=fail reason=\"signature verification failed\" (2048-bit key;\n\tunprotected) header.d=gmail.com header.i=@gmail.com\n\theader.b=\"IQLsHeQW\"; dkim-atps=neutral"],"Received":["from vger.kernel.org (vger.kernel.org [209.132.180.67])\n\tby ozlabs.org (Postfix) with ESMTP id 3xwFgy2wL7z9s83\n\tfor <incoming-dt@patchwork.ozlabs.org>;\n\tMon, 18 Sep 2017 02:58:06 +1000 (AEST)","(majordomo@vger.kernel.org) by vger.kernel.org via listexpand\n\tid S1751586AbdIQQ6E (ORCPT\n\t<rfc822;incoming-dt@patchwork.ozlabs.org>);\n\tSun, 17 Sep 2017 12:58:04 -0400","from mail-wr0-f195.google.com ([209.85.128.195]:34030 \"EHLO\n\tmail-wr0-f195.google.com\" rhost-flags-OK-OK-OK-OK) by vger.kernel.org\n\twith ESMTP id S1751466AbdIQQ6D (ORCPT\n\t<rfc822; devicetree@vger.kernel.org>); Sun, 17 Sep 2017 12:58:03 -0400","by mail-wr0-f195.google.com with SMTP id k20so3830628wre.1;\n\tSun, 17 Sep 2017 09:58:02 -0700 (PDT)","from [192.168.1.18] (dkn149.neoplus.adsl.tpnet.pl. 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The \"led\" property in the\n> > +LED specific nodes tells the numerical ID of each individual LED. The\n> > +\"led\" property is used here in a similar fashion as the \"reg\" property\n> > +in DT. [3]\n> > +\n> > +Referring to LEDs in Device tree is documented in [4], in \"flash-leds\"\n> > +property documentation. In short, LEDs are directly referred to by\n> > +using phandles.\n> > +\n> > +While Device tree allows referring to any node in the tree[1], in ACPI\n> > +references are limited to device nodes only [2]. For this reason using\n> > +the same mechanism on ACPI is not possible.\n> > +\n> > +ACPI allows (as does DT) using integer arguments after the reference.\n> > +A combination of the LED driver device reference and an integer\n> > +argument, referring to the \"led\" property of the relevant LED, are\n> > +use to individual LEDs.\n> \n> s/are use/is used/ ? (in a sense \"combination of ... and .. is used\")\n> \n> s/to individual/to describe individual/\n> \n> (or another verb, I'm not sure what exactly you intended it to be)\n\nI'll use \"is used to identify\", for this is what it essentially is for.\n\n> \n>  The value of the LED property is a contract\n> > +between the firmware and software, it uniquely identifies the LED\n> > +driver outputs.\n> > +\n> > +An ASL example of a camera sensor device and a LED driver device for two\n> > +LEDs. Objects not relevant for LEDs or the references to them have been\n> > +omitted.\n> > +\n> > +\tDevice (LED)\n> > +\t{\n> > +\t\tName (_DSD, Package () {\n> > +\t\t\tToUUID(\"dbb8e3e6-5886-4ba6-8795-1319f52a966b\"),\n> > +\t\t\tPackage () {\n> > +\t\t\t\tPackage () { \"led0\", LED0 },\n> > +\t\t\t\tPackage () { \"led1\", LED1 },\n> > +\t\t\t}\n> > +\t\t})\n> > +\t\tName (LED0, Package () {\n> > +\t\t\tToUUID(\"daffd814-6eba-4d8c-8a91-bc9bbf4aa301\"),\n> > +\t\t\tPackage () {\n> > +\t\t\t\tPackage () { \"led\", 0 },\n> > +\t\t\t\tPackage () { \"flash-max-microamp\", 1000000 },\n> > +\t\t\t\tPackage () { \"flash-timeout-us\", 200000 },\n> > +\t\t\t\tPackage () { \"led-max-microamp\", 100000 },\n> > +\t\t\t\tPackage () { \"label\", \"led:salama\" },\n> > +\t\t\t}\n> > +\t\t})\n> > +\t\tName (LED1, Package () {\n> > +\t\t\tToUUID(\"daffd814-6eba-4d8c-8a91-bc9bbf4aa301\"),\n> > +\t\t\tPackage () {\n> > +\t\t\t\tPackage () { \"led\", 1 },\n> > +\t\t\t\tPackage () { \"led-max-microamp\", 10000 },\n> > +\t\t\t\tPackage () { \"label\", \"led:huomiovalo\" },\n> > +\t\t\t}\n> > +\t\t})\n> > +\t}\n> > +\n> > +\tDevice (SEN)\n> > +\t{\n> > +\t\tName (_DSD, Package () {\n> > +\t\t\tToUUID(\"daffd814-6eba-4d8c-8a91-bc9bbf4aa301\"),\n> > +\t\t\tPackage () {\n> > +\t\t\t\tPackage () {\n> > +\t\t\t\t\t\"flash-leds\",\n> > +\t\t\t\t\tPackage () { ^LED, 0, ^LED, 1 },\n> > +\t\t\t\t}\n> > +\t\t\t}\n> > +\t\t})\n> > +\t}\n> > +\n> > +where\n> > +\n> > +\tLED\tLED driver device\n> > +\tLED0\tFirst LED\n> > +\tLED1\tSecond LED\n> > +\tSEN\tCamera sensor device (or another device the LED is\n> > +\t\trelated to)\n> > +\n> > +[1] Device tree. <URL:http://www.devicetree.org>, referenced 2016-10-03.\n> > +\n> > +[2] Advanced Configuration and Power Interface Specification.\n> > +    <URL:http://www.uefi.org/sites/default/files/resources/ACPI_6_1.pdf>,\n> > +    referenced 2016-10-04.\n> > +\n> > +[3] Documentation/devicetree/bindings/leds/common.txt\n> > +\n> > +[4] Documentation/devicetree/bindings/media/video-interfaces.txt\n> > +\n> > +[5] Device Properties UUID For _DSD.\n> > +    <URL:http://www.uefi.org/sites/default/files/resources/_DSD-device-properties-UUID.pdf>,\n> > +    referenced 2016-10-04.\n> > +\n> > +[6] Hierarchical Data Extension UUID For _DSD.\n> > +    <URL:http://www.uefi.org/sites/default/files/resources/_DSD-hierarchical-data-extension-UUID-v1.pdf>,\n> > +    referenced 2016-10-04.\n> > \n> \n> -- \n> Best regards,\n> Jacek Anaszewski","headers":{"Return-Path":"<devicetree-owner@vger.kernel.org>","X-Original-To":"incoming-dt@patchwork.ozlabs.org","Delivered-To":"patchwork-incoming-dt@bilbo.ozlabs.org","Authentication-Results":"ozlabs.org;\n\tspf=none (mailfrom) smtp.mailfrom=vger.kernel.org\n\t(client-ip=209.132.180.67; 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Mon, 18 Sep 2017 13:34:20 +0300"],"Date":"Mon, 18 Sep 2017 13:34:20 +0300","From":"Sakari Ailus <sakari.ailus@iki.fi>","To":"Jacek Anaszewski <jacek.anaszewski@gmail.com>","Cc":"Sakari Ailus <sakari.ailus@linux.intel.com>,\n\tlinux-leds@vger.kernel.org, linux-acpi@vger.kernel.org,\n\tdevicetree@vger.kernel.org, mika.westerberg@intel.com, rafael@kernel.org","Subject":"Re: [PATCH 1/2] ACPI: Document how to refer to LEDs from remote\n\tnodes","Message-ID":"<20170918103419.qo3sw5vufqojj3vm@valkosipuli.retiisi.org.uk>","References":"<20170915144052.25903-1-sakari.ailus@linux.intel.com>\n\t<20170915144052.25903-2-sakari.ailus@linux.intel.com>\n\t<6baeee56-480b-00b9-4c84-e65dc7c42301@gmail.com>","MIME-Version":"1.0","Content-Type":"text/plain; charset=us-ascii","Content-Disposition":"inline","In-Reply-To":"<6baeee56-480b-00b9-4c84-e65dc7c42301@gmail.com>","User-Agent":"NeoMutt/20170113 (1.7.2)","Sender":"devicetree-owner@vger.kernel.org","Precedence":"bulk","List-ID":"<devicetree.vger.kernel.org>","X-Mailing-List":"devicetree@vger.kernel.org"}},{"id":1770389,"web_url":"http://patchwork.ozlabs.org/comment/1770389/","msgid":"<59f91a5f-bad2-b4a1-ae41-58073ba395b0@gmail.com>","list_archive_url":null,"date":"2017-09-18T18:14:10","subject":"Re: [PATCH 1/2] ACPI: Document how to refer to LEDs from remote\n\tnodes","submitter":{"id":66885,"url":"http://patchwork.ozlabs.org/api/people/66885/","name":"Jacek Anaszewski","email":"jacek.anaszewski@gmail.com"},"content":"Hi Sakari,\n\nOn 09/18/2017 12:34 PM, Sakari Ailus wrote:\n> Hi Jacek,\n> \n> Thanks for the feedback.\n> \n> On Sun, Sep 17, 2017 at 06:57:09PM +0200, Jacek Anaszewski wrote:\n>> Hi Sakari,\n>>\n>> Thanks for the patch.\n>>\n>> On 09/15/2017 04:40 PM, Sakari Ailus wrote:\n>>> Document referring to LEDs from remote device nodes, such as from camera\n>>> sensors.\n>>>\n>>> Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>\n>>> ---\n>>>  Documentation/acpi/dsd/leds.txt | 94 +++++++++++++++++++++++++++++++++++++++++\n>>>  1 file changed, 94 insertions(+)\n>>>  create mode 100644 Documentation/acpi/dsd/leds.txt\n>>>\n>>> diff --git a/Documentation/acpi/dsd/leds.txt b/Documentation/acpi/dsd/leds.txt\n>>> new file mode 100644\n>>> index 000000000000..894c82274f53\n>>> --- /dev/null\n>>> +++ b/Documentation/acpi/dsd/leds.txt\n>>> @@ -0,0 +1,94 @@\n>>> +Describing and referring to LEDs in ACPI\n>>> +\n>>> +Individual LEDs are described by hierarchical data extension [6] nodes\n>>> +under the device node, the LED driver chip. The \"led\" property in the\n>>> +LED specific nodes tells the numerical ID of each individual LED. The\n>>> +\"led\" property is used here in a similar fashion as the \"reg\" property\n>>> +in DT. [3]\n>>> +\n>>> +Referring to LEDs in Device tree is documented in [4], in \"flash-leds\"\n>>> +property documentation. In short, LEDs are directly referred to by\n>>> +using phandles.\n>>> +\n>>> +While Device tree allows referring to any node in the tree[1], in ACPI\n>>> +references are limited to device nodes only [2]. For this reason using\n>>> +the same mechanism on ACPI is not possible.\n>>> +\n>>> +ACPI allows (as does DT) using integer arguments after the reference.\n>>> +A combination of the LED driver device reference and an integer\n>>> +argument, referring to the \"led\" property of the relevant LED, are\n>>> +use to individual LEDs.\n>>\n>> s/are use/is used/ ? (in a sense \"combination of ... and .. is used\")\n>>\n>> s/to individual/to describe individual/\n>>\n>> (or another verb, I'm not sure what exactly you intended it to be)\n> \n> I'll use \"is used to identify\", for this is what it essentially is for.\n\nWith that:\n\nAcked-by: Jacek Anaszewski <jacek.anaszewski@gmail.com>\n\n>>  The value of the LED property is a contract\n>>> +between the firmware and software, it uniquely identifies the LED\n>>> +driver outputs.\n>>> +\n>>> +An ASL example of a camera sensor device and a LED driver device for two\n>>> +LEDs. Objects not relevant for LEDs or the references to them have been\n>>> +omitted.\n>>> +\n>>> +\tDevice (LED)\n>>> +\t{\n>>> +\t\tName (_DSD, Package () {\n>>> +\t\t\tToUUID(\"dbb8e3e6-5886-4ba6-8795-1319f52a966b\"),\n>>> +\t\t\tPackage () {\n>>> +\t\t\t\tPackage () { \"led0\", LED0 },\n>>> +\t\t\t\tPackage () { \"led1\", LED1 },\n>>> +\t\t\t}\n>>> +\t\t})\n>>> +\t\tName (LED0, Package () {\n>>> +\t\t\tToUUID(\"daffd814-6eba-4d8c-8a91-bc9bbf4aa301\"),\n>>> +\t\t\tPackage () {\n>>> +\t\t\t\tPackage () { \"led\", 0 },\n>>> +\t\t\t\tPackage () { \"flash-max-microamp\", 1000000 },\n>>> +\t\t\t\tPackage () { \"flash-timeout-us\", 200000 },\n>>> +\t\t\t\tPackage () { \"led-max-microamp\", 100000 },\n>>> +\t\t\t\tPackage () { \"label\", \"led:salama\" },\n>>> +\t\t\t}\n>>> +\t\t})\n>>> +\t\tName (LED1, Package () {\n>>> +\t\t\tToUUID(\"daffd814-6eba-4d8c-8a91-bc9bbf4aa301\"),\n>>> +\t\t\tPackage () {\n>>> +\t\t\t\tPackage () { \"led\", 1 },\n>>> +\t\t\t\tPackage () { \"led-max-microamp\", 10000 },\n>>> +\t\t\t\tPackage () { \"label\", \"led:huomiovalo\" },\n>>> +\t\t\t}\n>>> +\t\t})\n>>> +\t}\n>>> +\n>>> +\tDevice (SEN)\n>>> +\t{\n>>> +\t\tName (_DSD, Package () {\n>>> +\t\t\tToUUID(\"daffd814-6eba-4d8c-8a91-bc9bbf4aa301\"),\n>>> +\t\t\tPackage () {\n>>> +\t\t\t\tPackage () {\n>>> +\t\t\t\t\t\"flash-leds\",\n>>> +\t\t\t\t\tPackage () { ^LED, 0, ^LED, 1 },\n>>> +\t\t\t\t}\n>>> +\t\t\t}\n>>> +\t\t})\n>>> +\t}\n>>> +\n>>> +where\n>>> +\n>>> +\tLED\tLED driver device\n>>> +\tLED0\tFirst LED\n>>> +\tLED1\tSecond LED\n>>> +\tSEN\tCamera sensor device (or another device the LED is\n>>> +\t\trelated to)\n>>> +\n>>> +[1] Device tree. <URL:http://www.devicetree.org>, referenced 2016-10-03.\n>>> +\n>>> +[2] Advanced Configuration and Power Interface Specification.\n>>> +    <URL:http://www.uefi.org/sites/default/files/resources/ACPI_6_1.pdf>,\n>>> +    referenced 2016-10-04.\n>>> +\n>>> +[3] Documentation/devicetree/bindings/leds/common.txt\n>>> +\n>>> +[4] Documentation/devicetree/bindings/media/video-interfaces.txt\n>>> +\n>>> +[5] Device Properties UUID For _DSD.\n>>> +    <URL:http://www.uefi.org/sites/default/files/resources/_DSD-device-properties-UUID.pdf>,\n>>> +    referenced 2016-10-04.\n>>> +\n>>> +[6] Hierarchical Data Extension UUID For _DSD.\n>>> +    <URL:http://www.uefi.org/sites/default/files/resources/_DSD-hierarchical-data-extension-UUID-v1.pdf>,\n>>> +    referenced 2016-10-04.\n>>>\n>>\n>> -- \n>> Best regards,\n>> Jacek Anaszewski\n>","headers":{"Return-Path":"<devicetree-owner@vger.kernel.org>","X-Original-To":"incoming-dt@patchwork.ozlabs.org","Delivered-To":"patchwork-incoming-dt@bilbo.ozlabs.org","Authentication-Results":["ozlabs.org;\n\tspf=none (mailfrom) smtp.mailfrom=vger.kernel.org\n\t(client-ip=209.132.180.67; helo=vger.kernel.org;\n\tenvelope-from=devicetree-owner@vger.kernel.org; receiver=<UNKNOWN>)","ozlabs.org;\n\tdkim=fail reason=\"signature verification failed\" (2048-bit key;\n\tunprotected) header.d=gmail.com header.i=@gmail.com\n\theader.b=\"L9t7Rz02\"; dkim-atps=neutral"],"Received":["from vger.kernel.org (vger.kernel.org [209.132.180.67])\n\tby ozlabs.org (Postfix) with ESMTP id 3xwvLM6XXhz9s7p\n\tfor <incoming-dt@patchwork.ozlabs.org>;\n\tTue, 19 Sep 2017 04:15:07 +1000 (AEST)","(majordomo@vger.kernel.org) by vger.kernel.org via listexpand\n\tid S1752917AbdIRSPF (ORCPT\n\t<rfc822;incoming-dt@patchwork.ozlabs.org>);\n\tMon, 18 Sep 2017 14:15:05 -0400","from mail-wm0-f66.google.com ([74.125.82.66]:32869 \"EHLO\n\tmail-wm0-f66.google.com\" rhost-flags-OK-OK-OK-OK) by vger.kernel.org\n\twith ESMTP id S1752621AbdIRSPF (ORCPT\n\t<rfc822; devicetree@vger.kernel.org>); Mon, 18 Sep 2017 14:15:05 -0400","by mail-wm0-f66.google.com with SMTP id m127so1693042wmm.0;\n\tMon, 18 Sep 2017 11:15:04 -0700 (PDT)","from [192.168.1.18] (dkm159.neoplus.adsl.tpnet.pl. 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