From mboxrd@z Thu Jan  1 00:00:00 1970
From: John Garry <john.garry@huawei.com>
Subject: Re: [PATCH v3 1/4] ACPI / scan: Fix acpi_is_indirect_io_slave()
 always returning false
Date: Tue, 7 Aug 2018 11:05:13 +0100
Message-ID: <03dae627-a888-317a-ed43-6c374b1b54eb@huawei.com>
References: <20180807080539.17811-1-hdegoede@redhat.com>
 <20180807080539.17811-2-hdegoede@redhat.com>
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To: Hans de Goede <hdegoede@redhat.com>, "Rafael J . Wysocki" <rjw@rjwysocki.net>, Len Brown <lenb@kernel.org>, Andy Shevchenko <andriy.shevchenko@linux.intel.com>, Mika Westerberg <mika.westerberg@linux.intel.com>, Darren Hart <dvhart@infradead.org>, Wolfram Sang <wsa@the-dreams.de>
Cc: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>, linux-acpi@vger.kernel.org, platform-driver-x86@vger.kernel.org, linux-kernel@vger.kernel.org, Heikki Krogerus <heikki.krogerus@linux.intel.com>, linux-i2c@vger.kernel.org, stable@vger.kernel.org, Bjorn Helgaas <bhelgaas@google.com>, Dann Frazier <dann.frazier@canonical.com>, Linuxarm <linuxarm@huawei.com>
List-Id: linux-i2c@vger.kernel.org

On 07/08/2018 09:05, Hans de Goede wrote:
> Since commit 63347db0affa ("ACPI / scan: Use acpi_bus_get_status() to
> initialize ACPI_TYPE_DEVICE devs") the status field of normal acpi_devices
> gets set to 0 by acpi_bus_type_and_status() and filled with its actual
> value later when acpi_add_single_object() calls acpi_bus_get_status().
>
> This means that status is 0 when acpi_device_enumeration_by_parent()
> gets called which makes the acpi_match_device_ids() call in
> acpi_is_indirect_io_slave() always return -ENOENT.

For for the (child) device the status may be zero, but how about the 
parent device (which is what we care about)? As I see, we would have set 
the parent device status present field at this stage.

Thanks,
John

>
> This commit fixes this by making acpi_bus_type_and_status() set status to
> ACPI_STA_DEFAULT until acpi_add_single_object() calls acpi_bus_get_status()
>
> Fixes: dfda4492322e ("ACPI / scan: Do not enumerate Indirect IO host children")
> Cc: stable@vger.kernel.org
> Cc: John Garry <john.garry@huawei.com>
> Cc: Bjorn Helgaas <bhelgaas@google.com>
> Cc: Dann Frazier <dann.frazier@canonical.com>
> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
> ---
>  drivers/acpi/scan.c | 5 +++--
>  1 file changed, 3 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c
> index 970dd87d347c..6799d00dd790 100644
> --- a/drivers/acpi/scan.c
> +++ b/drivers/acpi/scan.c
> @@ -1612,7 +1612,8 @@ static int acpi_add_single_object(struct acpi_device **child,
>  	 * Note this must be done before the get power-/wakeup_dev-flags calls.
>  	 */
>  	if (type == ACPI_BUS_TYPE_DEVICE)
> -		acpi_bus_get_status(device);
> +		if (acpi_bus_get_status(device) < 0)
> +			acpi_set_device_status(device, 0);
>
>  	acpi_bus_get_power_flags(device);
>  	acpi_bus_get_wakeup_device_flags(device);
> @@ -1690,7 +1691,7 @@ static int acpi_bus_type_and_status(acpi_handle handle, int *type,
>  		 * acpi_add_single_object updates this once we've an acpi_device
>  		 * so that acpi_bus_get_status' quirk handling can be used.
>  		 */
> -		*sta = 0;
> +		*sta = ACPI_STA_DEFAULT;
>  		break;
>  	case ACPI_TYPE_PROCESSOR:
>  		*type = ACPI_BUS_TYPE_PROCESSOR;
>