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2024-08-13usb: gadget: f_fs: add capability for dfu functional descriptorDavid Sands1-0/+2
Add the ability for the USB FunctionFS (FFS) gadget driver to be able to create Device Firmware Upgrade (DFU) functional descriptors. [1] This patch allows implementation of DFU in userspace using the FFS gadget. The DFU protocol uses the control pipe (ep0) for all messaging so only the addition of the DFU functional descriptor is needed in the kernel driver. The DFU functional descriptor is written to the ep0 file along with any other descriptors during FFS setup. DFU requires an interface descriptor followed by the DFU functional descriptor. This patch includes documentation of the added descriptor for DFU and conversion of some existing documentation to kernel-doc format so that it can be included in the generated docs. An implementation of DFU 1.1 that implements just the runtime descriptor using the FunctionFS gadget (with rebooting into u-boot for DFU mode) has been tested on an i.MX8 Nano. An implementation of DFU 1.1 that implements both runtime and DFU mode using the FunctionFS gadget has been tested on Xilinx Zynq UltraScale+. Note that for the best performance of firmware update file transfers, the userspace program should respond as quick as possible to the setup packets. [1] https://www.usb.org/sites/default/files/DFU_1.1.pdf Signed-off-by: David Sands <david.sands@biamp.com> Co-developed-by: Chris Wulff <crwulff@gmail.com> Signed-off-by: Chris Wulff <crwulff@gmail.com> Link: https://lore.kernel.org/r/20240811000004.1395888-2-crwulff@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-02-17Documentation: usb: Document FunctionFS DMABUF APIPaul Cercueil1-0/+36
Add documentation for the three ioctls used to attach or detach externally-created DMABUFs, and to request transfers from/to previously attached DMABUFs. Signed-off-by: Paul Cercueil <paul@crapouillou.net> Link: https://lore.kernel.org/r/20240130122340.54813-5-paul@crapouillou.net Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-11-22Documentation: USB: correct possessive "its" usageRandy Dunlap1-1/+1
Correct uses of "it's" to possessive "its" or "its" to "it's" as needed. Correct associated grammar in one location. Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: linux-usb@vger.kernel.org Link: https://lore.kernel.org/r/20221118231422.14076-1-rdunlap@infradead.org Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-06-20docs: usb: rename files to .rst and add them to drivers-apiMauro Carvalho Chehab1-0/+68
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>