2016-12-16 14:42:38

by Lorenzo Pieralisi

[permalink] [raw]
Subject: [PATCH] ACPI: Remove misplaced acpi_dma_deconfigure() call in acpi_bind_one()

The acpi_bind_one() error return path can be hit either on physical node
allocation failure or if the device being configured is already
associated with an ACPI node and its ACPI companion does not match the
one acpi_bind_one() is setting it up with. In both cases the error
return path is executed before DMA is configured for a device therefore
there is no need to call acpi_dma_deconfigure() on the function error
return path.

Furthermore, if acpi_bind_one() does configure DMA for a device (ie it
successfully executes acpi_dma_configure()) acpi_bind_one() always
completes execution successfully hence there is no need to add an exit
path to deconfigure the DMA set-up (ie by calling acpi_dma_deconfigure()).

Remove the misplaced acpi_dma_deconfigure() in acpi_bind_one() to
reinstate its correct error return path behaviour.

Fixes: d760a1baf20e ("ACPI: Implement acpi_dma_configure")
Signed-off-by: Lorenzo Pieralisi <[email protected]>
Cc: Hanjun Guo <[email protected]>
Cc: Sudeep Holla <[email protected]>
Cc: "Rafael J. Wysocki" <[email protected]>
---
drivers/acpi/glue.c | 1 -
1 file changed, 1 deletion(-)

diff --git a/drivers/acpi/glue.c b/drivers/acpi/glue.c
index f8d6564..eb709e7 100644
--- a/drivers/acpi/glue.c
+++ b/drivers/acpi/glue.c
@@ -250,7 +250,6 @@ int acpi_bind_one(struct device *dev, struct acpi_device *acpi_dev)
return 0;

err:
- acpi_dma_deconfigure(dev);
ACPI_COMPANION_SET(dev, NULL);
put_device(dev);
put_device(&acpi_dev->dev);
--
2.10.0


2016-12-24 07:47:15

by Hanjun Guo

[permalink] [raw]
Subject: Re: [PATCH] ACPI: Remove misplaced acpi_dma_deconfigure() call in acpi_bind_one()

On 2016/12/16 22:43, Lorenzo Pieralisi wrote:
> The acpi_bind_one() error return path can be hit either on physical node
> allocation failure or if the device being configured is already
> associated with an ACPI node and its ACPI companion does not match the
> one acpi_bind_one() is setting it up with. In both cases the error
> return path is executed before DMA is configured for a device therefore
> there is no need to call acpi_dma_deconfigure() on the function error
> return path.
>
> Furthermore, if acpi_bind_one() does configure DMA for a device (ie it
> successfully executes acpi_dma_configure()) acpi_bind_one() always
> completes execution successfully hence there is no need to add an exit
> path to deconfigure the DMA set-up (ie by calling acpi_dma_deconfigure()).
>
> Remove the misplaced acpi_dma_deconfigure() in acpi_bind_one() to
> reinstate its correct error return path behaviour.
>
> Fixes: d760a1baf20e ("ACPI: Implement acpi_dma_configure")
> Signed-off-by: Lorenzo Pieralisi <[email protected]>
> Cc: Hanjun Guo <[email protected]>
> Cc: Sudeep Holla <[email protected]>
> Cc: "Rafael J. Wysocki" <[email protected]>
> ---
> drivers/acpi/glue.c | 1 -
> 1 file changed, 1 deletion(-)
>
> diff --git a/drivers/acpi/glue.c b/drivers/acpi/glue.c
> index f8d6564..eb709e7 100644
> --- a/drivers/acpi/glue.c
> +++ b/drivers/acpi/glue.c
> @@ -250,7 +250,6 @@ int acpi_bind_one(struct device *dev, struct acpi_device *acpi_dev)
> return 0;
>
> err:
> - acpi_dma_deconfigure(dev);
> ACPI_COMPANION_SET(dev, NULL);
> put_device(dev);
> put_device(&acpi_dev->dev);

Reviewed-by: Hanjun Guo <[email protected]>

Thanks
Hanjun