Hi Toshi,
On Mon, Nov 26, 2012 at 05:10:21PM -0700, Toshi Kani wrote:
> On Fri, 2012-11-23 at 18:50 +0100, Vasilis Liaskovitis wrote:
> > This function should be registered for devices that need to execute some
> > non-acpi related action in order to be safely removed. If this function
> > returns zero, the acpi core can continue with removing the device.
> >
> > Make acpi_bus_remove call the device-specific prepare_remove callback before
> > removing the device. If prepare_remove fails, the removal is aborted.
> >
> > Signed-off-by: Vasilis Liaskovitis <vasilis.liaskovitis@xxxxxxxxxxxxxxxx>
> > ---
> > drivers/acpi/scan.c | 9 ++++++++-
> > include/acpi/acpi_bus.h | 2 ++
> > 2 files changed, 10 insertions(+), 1 deletions(-)
> >
> > diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c
> > index 8c4ac6d..e1c1d5d 100644
> > --- a/drivers/acpi/scan.c
> > +++ b/drivers/acpi/scan.c
> > @@ -1380,10 +1380,16 @@ static int acpi_device_set_context(struct acpi_device *device)
> >
> > static int acpi_bus_remove(struct acpi_device *dev, int rmdevice)
> > {
> > + int ret = 0;
> > if (!dev)
> > return -EINVAL;
> >
> > dev->removal_type = ACPI_BUS_REMOVAL_EJECT;
> > +
> > + if (dev->driver && dev->driver->ops.prepare_remove)
> > + ret = dev->driver->ops.prepare_remove(dev);
> > + if (ret)
> > + return ret;
>
> Hi Vasilis,
>
> The above code should be like below. Then you do not need to initialize
> ret, either. Please also add some comments explaining about
> prepare_remove can fail, but remove cannot.
>
> if (dev->driver && dev->driver->ops.prepare_remove) {
> ret = dev->driver->ops.prepare_remove(dev);
> if (ret)
> return ret;
> }
right.
>
> > device_release_driver(&dev->dev);
> >
> > if (!rmdevice)
> > @@ -1702,7 +1708,8 @@ int acpi_bus_trim(struct acpi_device *start, int rmdevice)
> > err = acpi_bus_remove(child, rmdevice);
> > else
> > err = acpi_bus_remove(child, 1);
> > -
> > + if (err)
> > + return err;
> > continue;
> > }
> >
> > diff --git a/include/acpi/acpi_bus.h b/include/acpi/acpi_bus.h
> > index 7ced5dc..9d94a55 100644
> > --- a/include/acpi/acpi_bus.h
> > +++ b/include/acpi/acpi_bus.h
> > @@ -94,6 +94,7 @@ typedef int (*acpi_op_start) (struct acpi_device * device);
> > typedef int (*acpi_op_bind) (struct acpi_device * device);
> > typedef int (*acpi_op_unbind) (struct acpi_device * device);
> > typedef void (*acpi_op_notify) (struct acpi_device * device, u32 event);
> > +typedef int (*acpi_op_prepare_remove) (struct acpi_device *device);
> >
> > struct acpi_bus_ops {
> > u32 acpi_op_add:1;
> > @@ -107,6 +108,7 @@ struct acpi_device_ops {
> > acpi_op_bind bind;
> > acpi_op_unbind unbind;
> > acpi_op_notify notify;
> > + acpi_op_prepare_remove prepare_remove;
>
> I'd prefer pre_remove, which indicates this interface is called before
> remove. prepare_remove sounds as if it only performs preparation, which
> may be misleading.
ok, I 'll use pre_remove from now on.
>
> BTW, Rafael mentioned we should avoid extending ACPI driver's
> interface... But I do not have other idea, either.
If we reach agreement that this is the approach we want, I 'll resend the series.
thanks,
- Vasilis
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