From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752186AbaCIRtJ (ORCPT ); Sun, 9 Mar 2014 13:49:09 -0400 Received: from v094114.home.net.pl ([79.96.170.134]:50589 "HELO v094114.home.net.pl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1751329AbaCIRtI (ORCPT ); Sun, 9 Mar 2014 13:49:08 -0400 From: "Rafael J. Wysocki" To: Zhang Rui Cc: linux-acpi@vger.kernel.org, linux-kernel@vger.kernel.org, bhelgaas@google.com, matthew.garrett@nebula.com, rafael.j.wysocki@intel.com, dmitry.torokhov@gmail.com Subject: Re: [RFC PATCH 6/8] ACPI: use platform bus as the default bus for _HID enumeration Date: Sun, 09 Mar 2014 19:04:23 +0100 Message-ID: <6354388.qLqPjcP6yZ@vostro.rjw.lan> User-Agent: KMail/4.11.5 (Linux/3.13.0+; KDE/4.11.5; x86_64; ; ) In-Reply-To: <1394380237.9269.31.camel@rzhang1-mobl4> References: <1393405874-3266-1-git-send-email-rui.zhang@intel.com> <1393405874-3266-7-git-send-email-rui.zhang@intel.com> <1394380237.9269.31.camel@rzhang1-mobl4> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="utf-8" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sunday, March 09, 2014 11:50:37 PM Zhang Rui wrote: > On Wed, 2014-02-26 at 17:11 +0800, Zhang Rui wrote: > > Because of the growing demand for enumerating ACPI devices to platform bus, > > this patch changes the code to enumerate ACPI devices with _HID/_CID to > > platform bus by default, unless the device already has a scan handler attached. > > > > Signed-off-by: Zhang Rui > > --- > > drivers/acpi/acpi_platform.c | 28 ---------------------------- > > drivers/acpi/scan.c | 12 ++++++------ > > 2 files changed, 6 insertions(+), 34 deletions(-) > > > > diff --git a/drivers/acpi/acpi_platform.c b/drivers/acpi/acpi_platform.c > > index dbfe49e..33376a9 100644 > > --- a/drivers/acpi/acpi_platform.c > > +++ b/drivers/acpi/acpi_platform.c > > @@ -22,24 +22,6 @@ > > > > ACPI_MODULE_NAME("platform"); > > > > -/* > > - * The following ACPI IDs are known to be suitable for representing as > > - * platform devices. > > - */ > > -static const struct acpi_device_id acpi_platform_device_ids[] = { > > - > > - { "PNP0D40" }, > > - { "ACPI0003" }, > > - { "VPC2004" }, > > - { "BCM4752" }, > > - > > - /* Intel Smart Sound Technology */ > > - { "INT33C8" }, > > - { "80860F28" }, > > - > > - { } > > -}; > > - > > /** > > * acpi_create_platform_device - Create platform device for ACPI device node > > * @adev: ACPI device node to create a platform device for. > > @@ -125,13 +107,3 @@ int acpi_create_platform_device(struct acpi_device *adev, > > kfree(resources); > > return 1; > > } > > - > > -static struct acpi_scan_handler platform_handler = { > > - .ids = acpi_platform_device_ids, > > - .attach = acpi_create_platform_device, > > -}; > > - > > -void __init acpi_platform_init(void) > > -{ > > - acpi_scan_add_handler(&platform_handler); > > -} > > diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c > > index 5967338..61af32e 100644 > > --- a/drivers/acpi/scan.c > > +++ b/drivers/acpi/scan.c > > @@ -2022,14 +2022,15 @@ static int acpi_scan_attach_handler(struct acpi_device *device) > > handler = acpi_scan_match_handler(hwid->id, &devid); > > if (handler) { > > ret = handler->attach(device, devid); > > - if (ret > 0) { > > + if (ret > 0) > > device->handler = handler; > > - break; > > - } else if (ret < 0) { > > - break; > > - } > > + if (ret) > > + goto end; > > } > > } > > +end: > > + if (!list_empty(&device->pnp.ids) && !device->handler) > > + acpi_create_platform_device(device, NULL); > > I just found a big problem in this proposal, which affects all the > optional scan handlers. What do you mean by "optional"? Such that can be compiled out? > The problem is that, if we disable a scan handler, platform device nodes > would be created instead by the code above, because there is no scan > handler attached for those ACPI nodes. If "we disable a scan handled" means "we compile it out", I'm not sure why creating platform devices for the device objects in question will be incorrect? Rafael