Hi Heinrich, On Fri, 16 Sept 2022 at 00:41, Heinrich Schuchardt <heinrich.schucha...@canonical.com> wrote: > > > > On 9/16/22 03:30, Simon Glass wrote: > > Hi Heinrich, > > > > On Thu, 15 Sept 2022 at 14:02, Heinrich Schuchardt > > <heinrich.schucha...@canonical.com> wrote: > >> > >> Currently block devices are only identified by uclass_id and device number. > >> When dealing with removable media this is not enough to uniquely identify > >> the medium. > >> > >> E.g. after host unbind, host bind we can have the same device number but a > >> different backing file. > >> > >> The EFI specification uses a 32bit number media ID to identify media. Add a > >> matching field to the block device descriptor. > >> > >> Signed-off-by: Heinrich Schuchardt <heinrich.schucha...@canonical.com> > >> --- > >> drivers/block/blk-uclass.c | 16 +++++++++++++++- > >> include/blk.h | 11 +++++++++++ > >> 2 files changed, 26 insertions(+), 1 deletion(-) > > > > Shouldn't this be handled by connecting the EFI data to its udevice. > > I think Takahiro has been looking at this? > > > > NAK to any EFI fields in blk_desc, in any case > > The information that a medium has changed can only come from the DM > layer. If for instance the SD-card is swapped, this is indicated by the > card detector switch. USB also has a signal for media changes. > > What are your ideas how the DM layer shall indicate media changes?
It should send an event, e.g. EVT_MEDIA and subscribers can then do what is needed. Regards, Simon