linux.git/Documentation/usb, branch v5.7 Linux kernel source tree usb: raw-gadget: documentation updates 2020-05-14T09:30:18+00:00 Andrey Konovalov andreyknvl@google.com 2020-05-07T17:06:58+00:00 61d2658db48af0c563d126cccc5c1105137b1ec9 Mention the issue with fixed UDC addresses. Links external examples and test suite. Add more implmenetation details and potential improvements. Signed-off-by: Andrey Konovalov <andreyknvl@google.com> Signed-off-by: Felipe Balbi <balbi@kernel.org> 
Mention the issue with fixed UDC addresses.

Links external examples and test suite.

Add more implmenetation details and potential improvements.

Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Felipe Balbi <balbi@kernel.org>
usb: raw-gadget: support stalling/halting/wedging endpoints 2020-05-14T09:30:18+00:00 Andrey Konovalov andreyknvl@google.com 2020-05-07T17:06:57+00:00 c61769bd4777a922952aed0d042a2572e5bd9b74 Raw Gadget is currently unable to stall/halt/wedge gadget endpoints, which is required for proper emulation of certain USB classes. This patch adds a few more ioctls: - USB_RAW_IOCTL_EP0_STALL allows to stall control endpoint #0 when there's a pending setup request for it. - USB_RAW_IOCTL_SET/CLEAR_HALT/WEDGE allow to set/clear halt/wedge status on non-control non-isochronous endpoints. Fixes: f2c2e717642c ("usb: gadget: add raw-gadget interface") Signed-off-by: Andrey Konovalov <andreyknvl@google.com> Signed-off-by: Felipe Balbi <balbi@kernel.org> 
Raw Gadget is currently unable to stall/halt/wedge gadget endpoints,
which is required for proper emulation of certain USB classes.

This patch adds a few more ioctls:

- USB_RAW_IOCTL_EP0_STALL allows to stall control endpoint #0 when
  there's a pending setup request for it.
- USB_RAW_IOCTL_SET/CLEAR_HALT/WEDGE allow to set/clear halt/wedge status
  on non-control non-isochronous endpoints.

Fixes: f2c2e717642c ("usb: gadget: add raw-gadget interface")
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Felipe Balbi <balbi@kernel.org>
usb: raw-gadget: fix gadget endpoint selection 2020-05-14T09:30:17+00:00 Andrey Konovalov andreyknvl@google.com 2020-05-07T17:06:56+00:00 97df5e5758f7d1dd0ca97e3210696818fc45bdb3 Currently automatic gadget endpoint selection based on required features doesn't work. Raw Gadget tries iterating over the list of available endpoints and finding one that has the right direction and transfer type. Unfortunately selecting arbitrary gadget endpoints (even if they satisfy feature requirements) doesn't work, as (depending on the UDC driver) they might have fixed addresses, and one also needs to provide matching endpoint addresses in the descriptors sent to the host. The composite framework deals with this by assigning endpoint addresses in usb_ep_autoconfig() before enumeration starts. This approach won't work with Raw Gadget as the endpoints are supposed to be enabled after a set_configuration/set_interface request from the host, so it's too late to patch the endpoint descriptors that had already been sent to the host. For Raw Gadget we take another approach. Similarly to GadgetFS, we allow the user to make the decision as to which gadget endpoints to use. This patch adds another Raw Gadget ioctl USB_RAW_IOCTL_EPS_INFO that exposes information about all non-control endpoints that a currently connected UDC has. This information includes endpoints addresses, as well as their capabilities and limits to allow the user to choose the most fitting gadget endpoint. The USB_RAW_IOCTL_EP_ENABLE ioctl is updated to use the proper endpoint validation routine usb_gadget_ep_match_desc(). These changes affect the portability of the gadgets that use Raw Gadget when running on different UDCs. Nevertheless, as long as the user relies on the information provided by USB_RAW_IOCTL_EPS_INFO to dynamically choose endpoint addresses, UDC-agnostic gadgets can still be written with Raw Gadget. Fixes: f2c2e717642c ("usb: gadget: add raw-gadget interface") Signed-off-by: Andrey Konovalov <andreyknvl@google.com> Signed-off-by: Felipe Balbi <balbi@kernel.org> 
Currently automatic gadget endpoint selection based on required features
doesn't work. Raw Gadget tries iterating over the list of available
endpoints and finding one that has the right direction and transfer type.
Unfortunately selecting arbitrary gadget endpoints (even if they satisfy
feature requirements) doesn't work, as (depending on the UDC driver) they
might have fixed addresses, and one also needs to provide matching
endpoint addresses in the descriptors sent to the host.

The composite framework deals with this by assigning endpoint addresses
in usb_ep_autoconfig() before enumeration starts. This approach won't work
with Raw Gadget as the endpoints are supposed to be enabled after a
set_configuration/set_interface request from the host, so it's too late to
patch the endpoint descriptors that had already been sent to the host.

For Raw Gadget we take another approach. Similarly to GadgetFS, we allow
the user to make the decision as to which gadget endpoints to use.

This patch adds another Raw Gadget ioctl USB_RAW_IOCTL_EPS_INFO that
exposes information about all non-control endpoints that a currently
connected UDC has. This information includes endpoints addresses, as well
as their capabilities and limits to allow the user to choose the most
fitting gadget endpoint.

The USB_RAW_IOCTL_EP_ENABLE ioctl is updated to use the proper endpoint
validation routine usb_gadget_ep_match_desc().

These changes affect the portability of the gadgets that use Raw Gadget
when running on different UDCs. Nevertheless, as long as the user relies
on the information provided by USB_RAW_IOCTL_EPS_INFO to dynamically
choose endpoint addresses, UDC-agnostic gadgets can still be written with
Raw Gadget.

Fixes: f2c2e717642c ("usb: gadget: add raw-gadget interface")
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Felipe Balbi <balbi@kernel.org>
usb: gadget: add raw-gadget interface 2020-03-15T09:34:48+00:00 Andrey Konovalov andreyknvl@google.com 2020-02-24T16:13:03+00:00 f2c2e717642c66f7fe7e5dd69b2e8ff5849f4d10 USB Raw Gadget is a kernel module that provides a userspace interface for the USB Gadget subsystem. Essentially it allows to emulate USB devices from userspace. Enabled with CONFIG_USB_RAW_GADGET. Raw Gadget is currently a strictly debugging feature and shouldn't be used in production. Raw Gadget is similar to GadgetFS, but provides a more low-level and direct access to the USB Gadget layer for the userspace. The key differences are: 1. Every USB request is passed to the userspace to get a response, while GadgetFS responds to some USB requests internally based on the provided descriptors. However note, that the UDC driver might respond to some requests on its own and never forward them to the Gadget layer. 2. GadgetFS performs some sanity checks on the provided USB descriptors, while Raw Gadget allows you to provide arbitrary data as responses to USB requests. 3. Raw Gadget provides a way to select a UDC device/driver to bind to, while GadgetFS currently binds to the first available UDC. 4. Raw Gadget uses predictable endpoint names (handles) across different UDCs (as long as UDCs have enough endpoints of each required transfer type). 5. Raw Gadget has ioctl-based interface instead of a filesystem-based one. Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Andrey Konovalov <andreyknvl@google.com> Signed-off-by: Felipe Balbi <balbi@kernel.org> 
USB Raw Gadget is a kernel module that provides a userspace interface for
the USB Gadget subsystem. Essentially it allows to emulate USB devices
from userspace. Enabled with CONFIG_USB_RAW_GADGET. Raw Gadget is
currently a strictly debugging feature and shouldn't be used in
production.

Raw Gadget is similar to GadgetFS, but provides a more low-level and
direct access to the USB Gadget layer for the userspace. The key
differences are:

1. Every USB request is passed to the userspace to get a response, while
   GadgetFS responds to some USB requests internally based on the provided
   descriptors. However note, that the UDC driver might respond to some
   requests on its own and never forward them to the Gadget layer.

2. GadgetFS performs some sanity checks on the provided USB descriptors,
   while Raw Gadget allows you to provide arbitrary data as responses to
   USB requests.

3. Raw Gadget provides a way to select a UDC device/driver to bind to,
   while GadgetFS currently binds to the first available UDC.

4. Raw Gadget uses predictable endpoint names (handles) across different
   UDCs (as long as UDCs have enough endpoints of each required transfer
   type).

5. Raw Gadget has ioctl-based interface instead of a filesystem-based one.

Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Felipe Balbi <balbi@kernel.org>
docs: usb: remove some broken references 2020-01-28T20:41:22+00:00 Mauro Carvalho Chehab mchehab+huawei@kernel.org 2020-01-28T06:41:00+00:00 1edca3c64e44df1665b0287fd536e79d74d884b6 It seems that some files were removed from USB documentation. Update the links accordingly. Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org> Link: https://lore.kernel.org/r/00008303fde6b4e06d027d3b76ae7032614a7030.1580193653.git.mchehab+huawei@kernel.org Signed-off-by: Jonathan Corbet <corbet@lwn.net> 
It seems that some files were removed from USB documentation.

Update the links accordingly.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Link: https://lore.kernel.org/r/00008303fde6b4e06d027d3b76ae7032614a7030.1580193653.git.mchehab+huawei@kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
USB: rio500: Remove Rio 500 kernel driver 2019-10-04T08:53:36+00:00 Bastien Nocera hadess@hadess.net 2019-09-23T16:18:43+00:00 015664d15270a112c2371d812f03f7c579b35a73 The Rio500 kernel driver has not been used by Rio500 owners since 2001 not long after the rio500 project added support for a user-space USB stack through the very first versions of usbdevfs and then libusb. Support for the kernel driver was removed from the upstream utilities in 2008: https://gitlab.freedesktop.org/hadess/rio500/commit/943f624ab721eb8281c287650fcc9e2026f6f5db Cc: Cesar Miquel <miquel@df.uba.ar> Signed-off-by: Bastien Nocera <hadess@hadess.net> Cc: stable <stable@vger.kernel.org> Link: https://lore.kernel.org/r/6251c17584d220472ce882a3d9c199c401a51a71.camel@hadess.net Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
The Rio500 kernel driver has not been used by Rio500 owners since 2001
not long after the rio500 project added support for a user-space USB stack
through the very first versions of usbdevfs and then libusb.

Support for the kernel driver was removed from the upstream utilities
in 2008:
https://gitlab.freedesktop.org/hadess/rio500/commit/943f624ab721eb8281c287650fcc9e2026f6f5db

Cc: Cesar Miquel <miquel@df.uba.ar>
Signed-off-by: Bastien Nocera <hadess@hadess.net>
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/6251c17584d220472ce882a3d9c199c401a51a71.camel@hadess.net
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
USB: Move wusbcore and UWB to staging as it is obsolete 2019-08-08T05:52:01+00:00 Greg Kroah-Hartman gregkh@linuxfoundation.org 2019-08-06T10:15:09+00:00 71ed79b0e4be0db254640c3beb9a1a0316eb5f61 The UWB and wusbcore code is long obsolete, so let us just move the code out of the real part of the kernel and into the drivers/staging/ location with plans to remove it entirely in a few releases. Link: https://lore.kernel.org/r/20190806101509.GA11280@kroah.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
The UWB and wusbcore code is long obsolete, so let us just move the code
out of the real part of the kernel and into the drivers/staging/
location with plans to remove it entirely in a few releases.

Link: https://lore.kernel.org/r/20190806101509.GA11280@kroah.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
docs: usb: rename files to .rst and add them to drivers-api 2019-06-20T12:28:36+00:00 Mauro Carvalho Chehab mchehab+samsung@kernel.org 2019-06-18T21:05:38+00:00 ecefae6db042283bf88ef3777f2381b18df8ed46 While there are a mix of things here, most of the stuff were written from Kernel developer's PoV. So, add them to the driver-api book. A follow up for this patch would be to move documents from there that are specific to sysadmins, adding them to the admin-guide. Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org> Acked-by: Johan Hovold <johan@kernel.org> Acked-by: Felipe Balbi <felipe.balbi@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
While there are a mix of things here, most of the stuff
were written from Kernel developer's PoV. So, add them to
the driver-api book.

A follow up for this patch would be to move documents from
there that are specific to sysadmins, adding them to the
admin-guide.

Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Acked-by: Johan Hovold <johan@kernel.org>
Acked-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
USB: rio500: update Documentation 2019-05-21T08:11:19+00:00 Oliver Neukum oneukum@suse.com 2019-05-09T09:31:01+00:00 53c7b63f797c96a30c21dd3b781fafaae096a12b Added the newly added limit and updated the text a bit Signed-off-by: Oliver Neukum <oneukum@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
Added the newly added limit and updated the text a bit

Signed-off-by: Oliver Neukum <oneukum@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
docs: usb: convert documents to ReST 2019-04-16T10:16:19+00:00 Mauro Carvalho Chehab mchehab+samsung@kernel.org 2019-04-16T02:56:01+00:00 d80b5005c5dd113442454b469752f0f95ac15645 Convert USB documents to ReST, in order to prepare for adding it to the kernel API book, as most of the stuff there are driver or subsystem-related. Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
Convert USB documents to ReST, in order to prepare for adding it
to the kernel API book, as most of the stuff there are driver or
subsystem-related.

Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>