Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756518Ab3GDNoS (ORCPT ); Thu, 4 Jul 2013 09:44:18 -0400 Received: from hydra.sisk.pl ([212.160.235.94]:58307 "EHLO hydra.sisk.pl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751468Ab3GDNoQ (ORCPT ); Thu, 4 Jul 2013 09:44:16 -0400 From: "Rafael J. Wysocki" To: Mika Westerberg Cc: Greg Kroah-Hartman , Bjorn Helgaas , "Rafael J. Wysocki" , Jesse Barnes , Yinghai Lu , john.ronciak@intel.com, miles.j.penner@intel.com, bruce.w.allan@intel.com, Heikki Krogerus , "Kirill A. Shutemov" , linux-kernel@vger.kernel.org, linux-acpi@vger.kernel.org, linux-pci@vger.kernel.org, x86@kernel.org Subject: Re: [PATCH v2 6/8] PCI: acpiphp: workaround for Thunderbolt on Acer Aspire S5 Date: Thu, 04 Jul 2013 15:53:55 +0200 Message-ID: <1656567.0oqS7xVYJ8@vostro.rjw.lan> User-Agent: KMail/4.9.5 (Linux/3.10.0-rc5+; KDE/4.9.5; x86_64; ; ) In-Reply-To: <20130704133314.GO4898@intel.com> References: <1372860295-8306-1-git-send-email-mika.westerberg@linux.intel.com> <5332719.huZ9ItKWz0@vostro.rjw.lan> <20130704133314.GO4898@intel.com> 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 Content-Length: 9196 Lines: 254 On Thursday, July 04, 2013 04:33:14 PM Mika Westerberg wrote: > On Thu, Jul 04, 2013 at 03:14:58PM +0200, Rafael J. Wysocki wrote: > > On Thursday, July 04, 2013 03:53:38 PM Mika Westerberg wrote: > > > On Thu, Jul 04, 2013 at 02:36:00PM +0200, Rafael J. Wysocki wrote: > > > > On Thursday, July 04, 2013 11:58:44 AM Mika Westerberg wrote: > > > > > On Wed, Jul 03, 2013 at 11:40:42PM +0200, Rafael J. Wysocki wrote: > > > > > > On Wednesday, July 03, 2013 05:04:53 PM Mika Westerberg wrote: > > > > > > > From: "Kirill A. Shutemov" > > > > > > > > > > > > > > Correct ACPI PCI hotplug imeplementation should have _RMV method in a > > > > > > > PCI slot (device under pci bridge). In Acer Aspire S5 case we have it > > > > > > > deeper in hierarchy: > > > > > > > > > > > > > > Device (RP05) > > > > > > > { > > > > > > > // ... > > > > > > > Device (HRUP) > > > > > > > { > > > > > > > // ... > > > > > > > Device (HRDN) > > > > > > > { > > > > > > > // ... > > > > > > > Device (EPUP) > > > > > > > { > > > > > > > // ... > > > > > > > Method (_RMV, 0, NotSerialized) // _RMV: Removal Status > > > > > > > { > > > > > > > Return (One) > > > > > > > } > > > > > > > } > > > > > > > } > > > > > > > } > > > > > > > } > > > > > > > > > > > > > > Signed-off-by: Kirill A. Shutemov > > > > > > > Signed-off-by: Mika Westerberg > > > > > > > --- > > > > > > > drivers/pci/hotplug/acpi_pcihp.c | 13 +++++++++++++ > > > > > > > 1 file changed, 13 insertions(+) > > > > > > > > > > > > > > diff --git a/drivers/pci/hotplug/acpi_pcihp.c b/drivers/pci/hotplug/acpi_pcihp.c > > > > > > > index 2a47e82..d92ebfb 100644 > > > > > > > --- a/drivers/pci/hotplug/acpi_pcihp.c > > > > > > > +++ b/drivers/pci/hotplug/acpi_pcihp.c > > > > > > > @@ -422,6 +422,19 @@ static int pcihp_is_ejectable(acpi_handle handle) > > > > > > > status = acpi_evaluate_integer(handle, "_RMV", NULL, &removable); > > > > > > > if (ACPI_SUCCESS(status) && removable) > > > > > > > return 1; > > > > > > > + > > > > > > > + /* > > > > > > > + * Workaround for Thunderbolt implementation on Acer Aspire S5. > > > > > > > + * > > > > > > > + * Correct ACPI PCI hotplug imeplementation has _RMV method in a PCI > > > > > > > + * slot (device under pci bridge). In Acer Aspire S5 case we have it > > > > > > > + * deeper in hierarchy. > > > > > > > + */ > > > > > > > + status = acpi_evaluate_integer(handle, "HRDN.EPUP._RMV", NULL, > > > > > > > + &removable); > > > > > > > > > > > > Well, calling stuff like this directly from a general function is kind of ugly. > > > > > > > > > > > > Can we use something like a quirk instead? A DMI check or something? > > > > > > > > > > Sure we can. How about something like the patch below? > > > > > > > > Well, it goes into the right (to me) direction. :-) > > > > > > > > Some comments below. > > > > > > > > > From: Mika Westerberg > > > > > Subject: [PATCH] PCI: acpiphp: workaround for Thunderbolt on Acer Aspire S5 > > > > > > > > > > The acpiphp driver finds out whether the device is removable by checking > > > > > whether it has _RMV method directly behind it (and if it returns 1). > > > > > However, at least on Acer Aspire S5 with Thunderbolt host router has this > > > > > method placed behind a device called EPUP (endpoint upstream port?) and not > > > > > in the usual place expected by the acpiphp driver. The ASL code below shows > > > > > how this is done on that machine: > > > > > > > > > > Device (RP05) > > > > > { > > > > > ... > > > > > Device (HRUP) > > > > > { > > > > > Name (_ADR, Zero) > > > > > Name (_PRW, Package (0x02) > > > > > { > > > > > 0x09, > > > > > 0x04 > > > > > }) > > > > > Device (HRDN) > > > > > { > > > > > Name (_ADR, 0x00040000) > > > > > Name (_PRW, Package (0x02) > > > > > { > > > > > 0x09, > > > > > 0x04 > > > > > }) > > > > > Device (EPUP) > > > > > { > > > > > Name (_ADR, Zero) > > > > > Method (_RMV, 0, NotSerialized) > > > > > { > > > > > Return (One) > > > > > } > > > > > } > > > > > } > > > > > } > > > > > ... > > > > > > > > > > Fix this by adding a DMI quirk for the Acer Aspire S5 machine that gives an > > > > > alternative path to the _RMV method. > > > > > > > > > > Signed-off-by: Kirill A. Shutemov > > > > > Signed-off-by: Mika Westerberg > > > > > --- > > > > > drivers/pci/hotplug/acpi_pcihp.c | 57 ++++++++++++++++++++++++++++++++++++---- > > > > > 1 file changed, 52 insertions(+), 5 deletions(-) > > > > > > > > > > diff --git a/drivers/pci/hotplug/acpi_pcihp.c b/drivers/pci/hotplug/acpi_pcihp.c > > > > > index 2a47e82..99fccf3 100644 > > > > > --- a/drivers/pci/hotplug/acpi_pcihp.c > > > > > +++ b/drivers/pci/hotplug/acpi_pcihp.c > > > > > @@ -33,6 +33,7 @@ > > > > > #include > > > > > #include > > > > > #include > > > > > +#include > > > > > > > > > > #define MY_NAME "acpi_pcihp" > > > > > > > > > > @@ -408,21 +409,67 @@ got_one: > > > > > } > > > > > EXPORT_SYMBOL(acpi_get_hp_hw_control_from_firmware); > > > > > > > > > > +/** > > > > > + * pcihp_is_removable - is the given ACPI device removable > > > > > + * @handle: ACPI handle of the device > > > > > + * > > > > > + * Try to find out whether the given ACPI device is removable by evaluating > > > > > + * its _RMV and returning the result. If we can't find the _RMV directly > > > > > + * under the device use system specific quirks to locate it. > > > > > + */ > > > > > +static bool pcihp_is_removable(acpi_handle handle) > > > > > +{ > > > > > > > > People are generally used to seeing DMI lists outside of functions. > > > > > > OK. > > > > > > > > + static const struct dmi_system_id rmv_paths[] = { > > > > > + { > > > > > + /* > > > > > + * On Acer Aspire S5 the _RMV method for the > > > > > + * Thunderbolt host router upstream port is not > > > > > + * located directly under the device but it is > > > > > + * instead placed a bit deeper in the hierarchy. > > > > > + */ > > > > > + .ident = "Acer Aspire S5", > > > > > + .matches = { > > > > > + DMI_MATCH(DMI_SYS_VENDOR, "Acer"), > > > > > + DMI_MATCH(DMI_PRODUCT_NAME, "Aspire S5-391"), > > > > > + }, > > > > > + .driver_data = "HRDN.EPUP._RMV", > > > > > > > > Use .callback instead? -> > > > > > > > > > + }, > > > > > + { } > > > > > + }; > > > > > + const struct dmi_system_id *id; > > > > > + unsigned long long removable; > > > > > + acpi_status status; > > > > > + > > > > > + status = acpi_evaluate_integer(handle, "_RMV", NULL, &removable); > > > > > + if (ACPI_SUCCESS(status)) > > > > > + return !!removable; > > > > > + > > > > > + /* Try system specific quirks */ > > > > > + id = dmi_first_match(rmv_paths); > > > > > + if (id && id->driver_data) { > > > > > > > > -> And here do > > > > > > > > if (id && id->callback) > > > > return id->callback(id); > > > > > > There is a problem with the above that we can't pass an ACPI handle to the > > > callback function. > > > > Ah, right. > > > > Well, you can do > > > > if (id && id->driver_data) { > > bool (*callback)(acpi_handle) = id->driver_data; > > > > return callback(handle); > > } > > > > although it's a bit hackish. > > I'm thinking that passing just the path from driver_data might be simpler > in this case ;-) But I'm fine with changing it to be a callback as well. No, it probably isn't worth the effort for just one system. > > > > > > > > > + char path[64]; > > > > > + > > > > > + strlcpy(path, id->driver_data, sizeof(path)); > > > > BTW, why didn't you want to pass id->driver_data directly here? > > acpi_evaluate_integer() takes acpi_string as parameter which is 'char *', > not 'const char *'. > > Doing: > > .driver_data = "HRDN.EPUP._RMV", > > might place that string to a read-only area (as it is constant), if I > understand C correctly. So even though I know that acpi_evaluate_interger() > doesn't change the parameter, there's no guarantee that it doesn't do that > in the future. I think you can safely assume that acpi_evaluate_integer() won't try to modify path (there are too many places where string literals are passed to it). IOW, please just pass id->driver_data to it. > > > > > > > > + status = acpi_evaluate_integer(handle, path, NULL, &removable); > > > > > + if (ACPI_SUCCESS(status)) > > > > > + return !!removable; > > > > > + } > > > > > + > > > > > + return false; > > > > > +} > > > > > + Thanks, Rafael -- I speak only for myself. Rafael J. Wysocki, Intel Open Source Technology Center. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/