| Message ID | 20231031035403.661938-1-maurora@google.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | usb: gadget: Support transfers from device memory | expand |
On Tue, Oct 31, 2023 at 03:54:02AM +0000, Manan Aurora wrote: > USB gadget stack only supports usb_request objects that point to buffers > located in memory. Support use cases where data is transferred from > physical addresses in device mmio regions > > Added a bit "pre_mapped" to usb_request to bypass dma_map_single and > dma_map_sg for such requests > > The caller must determine the dma address for the request before queuing > it > > Signed-off-by: Manan Aurora <maurora@google.com> > --- > drivers/usb/gadget/udc/core.c | 4 ++-- > include/linux/usb/gadget.h | 1 + > 2 files changed, 3 insertions(+), 2 deletions(-) > > diff --git a/drivers/usb/gadget/udc/core.c b/drivers/usb/gadget/udc/core.c > index ded9531f141b..236165ba08f4 100644 > --- a/drivers/usb/gadget/udc/core.c > +++ b/drivers/usb/gadget/udc/core.c > @@ -900,7 +900,7 @@ EXPORT_SYMBOL_GPL(usb_gadget_activate); > int usb_gadget_map_request_by_dev(struct device *dev, > struct usb_request *req, int is_in) > { > - if (req->length == 0) > + if (req->pre_mapped || req->length == 0) > return 0; > > if (req->num_sgs) { > @@ -948,7 +948,7 @@ EXPORT_SYMBOL_GPL(usb_gadget_map_request); > void usb_gadget_unmap_request_by_dev(struct device *dev, > struct usb_request *req, int is_in) > { > - if (req->length == 0) > + if (req->pre_mapped || req->length == 0) > return; > > if (req->num_mapped_sgs) { > diff --git a/include/linux/usb/gadget.h b/include/linux/usb/gadget.h > index a771ccc038ac..6bc035439098 100644 > --- a/include/linux/usb/gadget.h > +++ b/include/linux/usb/gadget.h > @@ -111,6 +111,7 @@ struct usb_request { > unsigned zero:1; > unsigned short_not_ok:1; > unsigned dma_mapped:1; > + unsigned pre_mapped:1; > > void (*complete)(struct usb_ep *ep, > struct usb_request *req); > -- > 2.42.0.820.g83a721a137-goog > > You can not add features/functionality that no in-kernel driver uses, so this can not be accepted as-is, sorry. Please submit it as part of a patch series where it is actually used, otherwise we have no idea if this is even something that we should do or not. thanks, greg k-h
On Tue, Oct 31, 2023 at 03:54:02AM +0000, Manan Aurora wrote: > USB gadget stack only supports usb_request objects that point to buffers > located in memory. Support use cases where data is transferred from > physical addresses in device mmio regions > > Added a bit "pre_mapped" to usb_request to bypass dma_map_single and > dma_map_sg for such requests > > The caller must determine the dma address for the request before queuing > it > > Signed-off-by: Manan Aurora <maurora@google.com> > --- > diff --git a/include/linux/usb/gadget.h b/include/linux/usb/gadget.h > index a771ccc038ac..6bc035439098 100644 > --- a/include/linux/usb/gadget.h > +++ b/include/linux/usb/gadget.h > @@ -111,6 +111,7 @@ struct usb_request { > unsigned zero:1; > unsigned short_not_ok:1; > unsigned dma_mapped:1; > + unsigned pre_mapped:1; > > void (*complete)(struct usb_ep *ep, > struct usb_request *req); You forgot to update the kerneldoc for struct usb_request. Alan Stern
diff --git a/drivers/usb/gadget/udc/core.c b/drivers/usb/gadget/udc/core.c index ded9531f141b..236165ba08f4 100644 --- a/drivers/usb/gadget/udc/core.c +++ b/drivers/usb/gadget/udc/core.c @@ -900,7 +900,7 @@ EXPORT_SYMBOL_GPL(usb_gadget_activate); int usb_gadget_map_request_by_dev(struct device *dev, struct usb_request *req, int is_in) { - if (req->length == 0) + if (req->pre_mapped || req->length == 0) return 0; if (req->num_sgs) { @@ -948,7 +948,7 @@ EXPORT_SYMBOL_GPL(usb_gadget_map_request); void usb_gadget_unmap_request_by_dev(struct device *dev, struct usb_request *req, int is_in) { - if (req->length == 0) + if (req->pre_mapped || req->length == 0) return; if (req->num_mapped_sgs) { diff --git a/include/linux/usb/gadget.h b/include/linux/usb/gadget.h index a771ccc038ac..6bc035439098 100644 --- a/include/linux/usb/gadget.h +++ b/include/linux/usb/gadget.h @@ -111,6 +111,7 @@ struct usb_request { unsigned zero:1; unsigned short_not_ok:1; unsigned dma_mapped:1; + unsigned pre_mapped:1; void (*complete)(struct usb_ep *ep, struct usb_request *req);
USB gadget stack only supports usb_request objects that point to buffers located in memory. Support use cases where data is transferred from physical addresses in device mmio regions Added a bit "pre_mapped" to usb_request to bypass dma_map_single and dma_map_sg for such requests The caller must determine the dma address for the request before queuing it Signed-off-by: Manan Aurora <maurora@google.com> --- drivers/usb/gadget/udc/core.c | 4 ++-- include/linux/usb/gadget.h | 1 + 2 files changed, 3 insertions(+), 2 deletions(-)