On Mon, Mar 29, 2010 at 12:18:43PM +0200, Michal Nazarewicz wrote: > Mass Storage Function (MSF) used the same descriptors for each > usb_function instance (meaning usb_function::descriptors of different > functions pointed to the same static area (the same was true for > usb_function::hs_descriptors)). > > This would leads to problems if MSF were used in several USB > configurations with different interface and/or endpoint numbers. > Descriptors for all configurations would have interface/endpoint > numbers overwritten by the values valid for the last configuration. > > This patch adds code that copies the descriptors each time MSF is > added to USB configuration (that is for each usb_function). > > Signed-off-by: Michal Nazarewicz <m.nazarewicz@xxxxxxxxxxx> > Cc: Kyungmin Park <kyungmin.park@xxxxxxxxxxx> > --- > drivers/usb/gadget/f_mass_storage.c | 32 ++++++++++++++++++++++++++------ > 1 files changed, 26 insertions(+), 6 deletions(-) > > diff --git a/drivers/usb/gadget/f_mass_storage.c b/drivers/usb/gadget/f_mass_storage.c > index f4911c0..9fccdc3 100644 > --- a/drivers/usb/gadget/f_mass_storage.c > +++ b/drivers/usb/gadget/f_mass_storage.c > @@ -2906,6 +2906,8 @@ static void fsg_unbind(struct usb_configuration *c, struct usb_function *f) > > DBG(fsg, "unbind\n"); > fsg_common_put(fsg->common); > + usb_free_descriptors(fsg->function.descriptors); > + usb_free_descriptors(fsg->function.hs_descriptors); > kfree(fsg); > } > > @@ -2946,7 +2948,13 @@ static int __init fsg_bind(struct usb_configuration *c, struct usb_function *f) > fsg_fs_bulk_in_desc.bEndpointAddress; > fsg_hs_bulk_out_desc.bEndpointAddress = > fsg_fs_bulk_out_desc.bEndpointAddress; > - f->hs_descriptors = fsg_hs_function; > + f->hs_descriptors = usb_copy_descriptors(fsg_hs_function); > + /* We don't care if we could not copy the high speed > + * descriptor. If we are out of memory we'll stick to > + * full speed only. Ie. it is an error that we cannot > + * copy hs descriptors but not a fatal one. */ > + /* if (unlikely(!f->hs_descriptors)) > + return -ENOMEM; */ I would much prefer to fail here and handle reloading a module in userspace over having a gadget operate on varying speeds, depending on a transient situation at module loading time that is not transparent to the user of an embedded device in the field for example. -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
