Re: [BUGFIX v2 1/4] ACPI, DOCK: initialize dock subsystem before scanning PCI root buses

[Jiang Liu <liuj97@gmail.com>]

On 06/15/2013 02:51 PM, Yinghai Lu wrote:
> On Fri, Jun 14, 2013 at 12:27 PM, Jiang Liu <jiang.liu@huawei.com> wrote:
>> Changeset "3b63aaa70e1 PCI: acpiphp: Do not use ACPI PCI subdriver
>> mechanism" causes a regression which breaks ACPI dock support,
>> please refer to https://bugzilla.kernel.org/show_bug.cgi?id=59501
>>
>> The root cause is that changeset 3b63aaa70e1 changed the relative
>> initialization order of ACPI dock subsystem and acpiphp driver,
>> and acpiphp driver has dependency on ACPI dock subsystem's
>> initialization result, so that acpiphp can't correctly detect ACPI
>> dock stations now.
>>
>> On the other hand, ACPI dock is a built-in driver, so we could
>> explicitly initialize it before the acpiphp driver is used.
>>
>> Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
>> Reported-by: Alexander E. Patrakov <patrakov@gmail.com>
>> Tested-by: Alexander E. Patrakov <patrakov@gmail.com>
>> Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
>> Cc: linux-acpi@vger.kernel.org
>> Cc: linux-kernel@vger.kernel.org
>> Cc: <stable@vger.kernel.org> # 3.9+
>> ---
>>  drivers/acpi/dock.c     | 7 +------
>>  drivers/acpi/internal.h | 5 +++++
>>  drivers/acpi/scan.c     | 1 +
>>  3 files changed, 7 insertions(+), 6 deletions(-)
>>
>> diff --git a/drivers/acpi/dock.c b/drivers/acpi/dock.c
>> index 4fdea38..02b0563 100644
>> --- a/drivers/acpi/dock.c
>> +++ b/drivers/acpi/dock.c
>> @@ -1033,7 +1033,7 @@ find_dock_and_bay(acpi_handle handle, u32 lvl, void *context, void **rv)
>>         return AE_OK;
>>  }
>>
>> -static int __init dock_init(void)
>> +int __init acpi_dock_init(void)
>>  {
>>         if (acpi_disabled)
>>                 return 0;
>> @@ -1062,9 +1062,4 @@ static void __exit dock_exit(void)
>>                 dock_remove(dock_station);
>>  }
>>
>> -/*
>> - * Must be called before drivers of devices in dock, otherwise we can't know
>> - * which devices are in a dock
>> - */
>> -subsys_initcall(dock_init);
>>  module_exit(dock_exit);
> 
> why not remove dock_exit?
I have a pending patchset to clean up dock driver, Rafael suggested to
focus on bugfix first, so I will send out the clean up patchset later.

> 
>> diff --git a/drivers/acpi/internal.h b/drivers/acpi/internal.h
>> index 297cbf4..c610a76 100644
>> --- a/drivers/acpi/internal.h
>> +++ b/drivers/acpi/internal.h
>> @@ -40,6 +40,11 @@ void acpi_container_init(void);
>>  #else
>>  static inline void acpi_container_init(void) {}
>>  #endif
>> +#ifdef CONFIG_ACPI_DOCK
>> +void acpi_dock_init(void);
>> +#else
>> +static inline void acpi_dock_init(void) {}
>> +#endif
>>  #ifdef CONFIG_ACPI_HOTPLUG_MEMORY
>>  void acpi_memory_hotplug_init(void);
>>  #else
>> diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c
>> index 44225cb..4148163 100644
>> --- a/drivers/acpi/scan.c
>> +++ b/drivers/acpi/scan.c
>> @@ -2045,6 +2045,7 @@ int __init acpi_scan_init(void)
>>         acpi_lpss_init();
>>         acpi_container_init();
>>         acpi_memory_hotplug_init();
>> +       acpi_dock_init();
>>
>>         mutex_lock(&acpi_scan_lock);
>>         /*
>> --
>> 1.8.1.2
>>