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[ Upstream commit 5d363120aa ]
This patch adds new config_ep_by_speed_and_alt function which
extends the config_ep_by_speed about alt parameter.
This additional parameter allows to find proper usb_ss_ep_comp_descriptor.
Problem has appeared during testing f_tcm (BOT/UAS) driver function.
f_tcm function for SS use array of headers for both BOT/UAS alternate
setting:
static struct usb_descriptor_header *uasp_ss_function_desc[] = {
(struct usb_descriptor_header *) &bot_intf_desc,
(struct usb_descriptor_header *) &uasp_ss_bi_desc,
(struct usb_descriptor_header *) &bot_bi_ep_comp_desc,
(struct usb_descriptor_header *) &uasp_ss_bo_desc,
(struct usb_descriptor_header *) &bot_bo_ep_comp_desc,
(struct usb_descriptor_header *) &uasp_intf_desc,
(struct usb_descriptor_header *) &uasp_ss_bi_desc,
(struct usb_descriptor_header *) &uasp_bi_ep_comp_desc,
(struct usb_descriptor_header *) &uasp_bi_pipe_desc,
(struct usb_descriptor_header *) &uasp_ss_bo_desc,
(struct usb_descriptor_header *) &uasp_bo_ep_comp_desc,
(struct usb_descriptor_header *) &uasp_bo_pipe_desc,
(struct usb_descriptor_header *) &uasp_ss_status_desc,
(struct usb_descriptor_header *) &uasp_status_in_ep_comp_desc,
(struct usb_descriptor_header *) &uasp_status_pipe_desc,
(struct usb_descriptor_header *) &uasp_ss_cmd_desc,
(struct usb_descriptor_header *) &uasp_cmd_comp_desc,
(struct usb_descriptor_header *) &uasp_cmd_pipe_desc,
NULL,
};
The first 5 descriptors are associated with BOT alternate setting,
and others are associated with UAS.
During handling UAS alternate setting f_tcm driver invokes
config_ep_by_speed and this function sets incorrect companion endpoint
descriptor in usb_ep object.
Instead setting ep->comp_desc to uasp_bi_ep_comp_desc function in this
case set ep->comp_desc to uasp_ss_bi_desc.
This is due to the fact that it searches endpoint based on endpoint
address:
for_each_ep_desc(speed_desc, d_spd) {
chosen_desc = (struct usb_endpoint_descriptor *)*d_spd;
if (chosen_desc->bEndpoitAddress == _ep->address)
goto ep_found;
}
And in result it uses the descriptor from BOT alternate setting
instead UAS.
Finally, it causes that controller driver during enabling endpoints
detect that just enabled endpoint for bot.
Signed-off-by: Jayshri Pawar <jpawar@cadence.com>
Signed-off-by: Pawel Laszczak <pawell@cadence.com>
Signed-off-by: Felipe Balbi <balbi@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
To understand all the Linux-USB framework, you'll use these resources:
* This source code. This is necessarily an evolving work, and
includes kerneldoc that should help you get a current overview.
("make pdfdocs", and then look at "usb.pdf" for host side and
"gadget.pdf" for peripheral side.) Also, Documentation/usb has
more information.
* The USB 2.0 specification (from www.usb.org), with supplements
such as those for USB OTG and the various device classes.
The USB specification has a good overview chapter, and USB
peripherals conform to the widely known "Chapter 9".
* Chip specifications for USB controllers. Examples include
host controllers (on PCs, servers, and more); peripheral
controllers (in devices with Linux firmware, like printers or
cell phones); and hard-wired peripherals like Ethernet adapters.
* Specifications for other protocols implemented by USB peripheral
functions. Some are vendor-specific; others are vendor-neutral
but just standardized outside of the www.usb.org team.
Here is a list of what each subdirectory here is, and what is contained in
them.
core/ - This is for the core USB host code, including the
usbfs files and the hub class driver ("hub_wq").
host/ - This is for USB host controller drivers. This
includes UHCI, OHCI, EHCI, and others that might
be used with more specialized "embedded" systems.
gadget/ - This is for USB peripheral controller drivers and
the various gadget drivers which talk to them.
Individual USB driver directories. A new driver should be added to the
first subdirectory in the list below that it fits into.
image/ - This is for still image drivers, like scanners or
digital cameras.
../input/ - This is for any driver that uses the input subsystem,
like keyboard, mice, touchscreens, tablets, etc.
../media/ - This is for multimedia drivers, like video cameras,
radios, and any other drivers that talk to the v4l
subsystem.
../net/ - This is for network drivers.
serial/ - This is for USB to serial drivers.
storage/ - This is for USB mass-storage drivers.
class/ - This is for all USB device drivers that do not fit
into any of the above categories, and work for a range
of USB Class specified devices.
misc/ - This is for all USB device drivers that do not fit
into any of the above categories.