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| author | Johan Hovold <johan@kernel.org> | 2017-03-17 11:35:30 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2017-03-23 13:53:16 +0100 |
| commit | 66a359390e7e34f9a4c489467234b107b3d76169 (patch) | |
| tree | e42bc277535cf39ea5f9249a1508f81f08e22d00 /include/linux/usb.h | |
| parent | 96cfcc9c461ca0a45ec223120984e1ae852f867e (diff) | |
| download | lwn-66a359390e7e34f9a4c489467234b107b3d76169.tar.gz lwn-66a359390e7e34f9a4c489467234b107b3d76169.zip | |
USB: core: add helpers to retrieve endpoints
Many USB drivers iterate over the available endpoints to find required
endpoints of a specific type and direction. Typically the endpoints are
required for proper function and a missing endpoint should abort probe.
To facilitate code reuse, add a helper to retrieve common endpoints
(bulk or interrupt, in or out) and four wrappers to find a single
endpoint.
Note that the helpers are marked as __must_check to serve as a reminder
to always verify that all expected endpoints are indeed present. This
also means that any optional endpoints, typically need to be looked up
through separate calls.
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'include/linux/usb.h')
| -rw-r--r-- | include/linux/usb.h | 35 |
1 files changed, 35 insertions, 0 deletions
diff --git a/include/linux/usb.h b/include/linux/usb.h index 148752640693..7041cc950737 100644 --- a/include/linux/usb.h +++ b/include/linux/usb.h @@ -99,6 +99,41 @@ enum usb_interface_condition { USB_INTERFACE_UNBINDING, }; +int __must_check +usb_find_common_endpoints(struct usb_host_interface *alt, + struct usb_endpoint_descriptor **bulk_in, + struct usb_endpoint_descriptor **bulk_out, + struct usb_endpoint_descriptor **int_in, + struct usb_endpoint_descriptor **int_out); + +static inline int __must_check +usb_find_bulk_in_endpoint(struct usb_host_interface *alt, + struct usb_endpoint_descriptor **bulk_in) +{ + return usb_find_common_endpoints(alt, bulk_in, NULL, NULL, NULL); +} + +static inline int __must_check +usb_find_bulk_out_endpoint(struct usb_host_interface *alt, + struct usb_endpoint_descriptor **bulk_out) +{ + return usb_find_common_endpoints(alt, NULL, bulk_out, NULL, NULL); +} + +static inline int __must_check +usb_find_int_in_endpoint(struct usb_host_interface *alt, + struct usb_endpoint_descriptor **int_in) +{ + return usb_find_common_endpoints(alt, NULL, NULL, int_in, NULL); +} + +static inline int __must_check +usb_find_int_out_endpoint(struct usb_host_interface *alt, + struct usb_endpoint_descriptor **int_out) +{ + return usb_find_common_endpoints(alt, NULL, NULL, NULL, int_out); +} + /** * struct usb_interface - what usb device drivers talk to * @altsetting: array of interface structures, one for each alternate |