On 2017-08-10 18:30, Jason Gunthorpe wrote:
On Thu, Aug 10, 2017 at 12:18:11PM +0200, Michal Suchánek wrote:
> Existing bus implementations do properly chain to driver shutdown (eg
> look at mmc_bus_shutdown) and it appears to have been written like
Neither isa nor ibmebus does. These are two random buses I tried to
I'm not following, I see this:
static void ibmebus_bus_device_shutdown(struct device *dev)
struct platform_device *of_dev = to_platform_device(dev);
struct platform_driver *drv = to_platform_driver(dev->driver);
if (dev->driver && drv->shutdown)
It looks to me like in this case the struct device_driver shutdown is
not used, and instead the struct platform_driver shutdown is called.
And it is not used even if a device driver sets it and expects it to
> this so that the bus can insert code before and after calling the
> driver shutdown.
So basically there is bus pre-shutdown and post-shutdown hook jumbled
together in one function.
and a redirect, apparently.
While I can understand the concept of post-shutdown hook I wonder
what gross hack would require a pre-shutdown hook.
TPM requires pre-shutdown.
Yes, a class pre-shutdown. Not a bus pre-shutdown, however.
I have no idea what business has a bus driver before a device shuts
The Linux development process at its best. There is poor design
implemented so when touching the code it is extended to worse because
I'm not sure I completely agree, there is obviously a lot going on with
If you want to go ahead with your patch then please also rename the
class shutdown to shutdown_pre to make it clear it is doing something
That makes sense.