usb: gadget: legacy: fix error return code of msg_bind()

When usb_otg_descriptor_alloc() returns NULL to usb_desc, no error
return code of msg_bind() is assigned.
To fix this bug, status is assigned with -ENOMEM in this case.

Reported-by: TOTE Robot <oslab@tsinghua.edu.cn>
Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com>
Link: https://lore.kernel.org/r/20210323123648.3997-1-baijiaju1990@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: gadget: mass_storage: use module_usb_composite_driver to simplify the code

module_usb_composite_driver() makes the code simpler by
eliminating boilerplate code.

Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Signed-off-by: Felipe Balbi <balbi@kernel.org>

usb: gadget: Remove set but not used variable 'opts' in msg_do_config

Fixes gcc '-Wunused-but-set-variable' warning:

drivers/usb/gadget/legacy/mass_storage.c: In function msg_do_config:
drivers/usb/gadget/legacy/mass_storage.c:108:19: warning: variable opts set but not used [-Wunused-but-set-variable]

It is not used since commit f78bbcae86e6 ("usb: f_mass_storage:
test whether thread is running before starting another")

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: zhengbin <zhengbin13@huawei.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>

usb: gadget: Remove set but not used variable 'opts' in msg_do_config

Fixes gcc '-Wunused-but-set-variable' warning:

drivers/usb/gadget/legacy/mass_storage.c: In function msg_do_config:
drivers/usb/gadget/legacy/mass_storage.c:108:19: warning: variable opts set but not used [-Wunused-but-set-variable]

It is not used since commit f78bbcae86e6 ("usb: f_mass_storage:
test whether thread is running before starting another")

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: zhengbin <zhengbin13@huawei.com>
Link: https://lore.kernel.org/r/1570610434-68293-3-git-send-email-zhengbin13@huawei.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: gadget: mass_storage: Set max_speed to SSP

Increase max_speed of the mass_storage driver for UDCs that support
SuperSpeed Plus. The composite driver will pass this value to UDC core
to set the device speed on probe (actual speed may be different
depending on whether the USB controller supports it or other external
factors).

Signed-off-by: Thinh Nguyen <thinhn@synopsys.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>

USB: gadget: legacy: Remove redundant license text

Now that the SPDX tag is in all USB files, that identifies the license
in a specific and legally-defined manner. So the extra GPL text wording
can be removed as it is no longer needed at all.

This is done on a quest to remove the 700+ different ways that files in
the kernel describe the GPL license text. And there's unneeded stuff
like the address (sometimes incorrect) for the FSF which is never
needed.

No copyright headers or other non-license-description text was removed.

Cc: Johan Hovold <johan@kernel.org>
Cc: Ruslan Bilovol <ruslan.bilovol@gmail.com>
Cc: Peter Chen <peter.chen@nxp.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: David Windsor <dwindsor@gmail.com>
Acked-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

USB: add SPDX identifiers to all remaining files in drivers/usb/

It's good to have SPDX identifiers in all files to make it easier to
audit the kernel tree for correct licenses.

Update the drivers/usb/ and include/linux/usb* files with the correct
SPDX license identifier based on the license text in the file itself.
The SPDX identifier is a legally binding shorthand, which can be used
instead of the full boiler plate text.

This work is based on a script and data from Thomas Gleixner, Philippe
Ombredanne, and Kate Stewart.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Kate Stewart <kstewart@linuxfoundation.org>
Cc: Philippe Ombredanne <pombredanne@nexb.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Acked-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

USB: g_mass_storage: Fix deadlock when driver is unbound

As a holdover from the old g_file_storage gadget, the g_mass_storage
legacy gadget driver attempts to unregister itself when its main
operating thread terminates (if it hasn't been unregistered already).
This is not strictly necessary; it was never more than an attempt to
have the gadget fail cleanly if something went wrong and the main
thread was killed.

However, now that the UDC core manages gadget drivers independently of
UDC drivers, this scheme doesn't work any more. A simple test:

modprobe dummy-hcd
modprobe g-mass-storage file=...
rmmod dummy-hcd

ends up in a deadlock with the following backtrace:

sysrq: SysRq : Show Blocked State
task PC stack pid father
file-storage D 0 1130 2 0x00000000
Call Trace:
__schedule+0x53e/0x58c
schedule+0x6e/0x77
schedule_preempt_disabled+0xd/0xf
__mutex_lock.isra.1+0x129/0x224
? _raw_spin_unlock_irqrestore+0x12/0x14
__mutex_lock_slowpath+0x12/0x14
mutex_lock+0x28/0x2b
usb_gadget_unregister_driver+0x29/0x9b [udc_core]
usb_composite_unregister+0x10/0x12 [libcomposite]
msg_cleanup+0x1d/0x20 [g_mass_storage]
msg_thread_exits+0xd/0xdd7 [g_mass_storage]
fsg_main_thread+0x1395/0x13d6 [usb_f_mass_storage]
? __schedule+0x573/0x58c
kthread+0xd9/0xdb
? do_set_interface+0x25c/0x25c [usb_f_mass_storage]
? init_completion+0x1e/0x1e
ret_from_fork+0x19/0x24
rmmod D 0 1155 683 0x00000000
Call Trace:
__schedule+0x53e/0x58c
schedule+0x6e/0x77
schedule_timeout+0x26/0xbc
? __schedule+0x573/0x58c
do_wait_for_common+0xb3/0x128
? usleep_range+0x81/0x81
? wake_up_q+0x3f/0x3f
wait_for_common+0x2e/0x45
wait_for_completion+0x17/0x19
fsg_common_put+0x34/0x81 [usb_f_mass_storage]
fsg_free_inst+0x13/0x1e [usb_f_mass_storage]
usb_put_function_instance+0x1a/0x25 [libcomposite]
msg_unbind+0x2a/0x42 [g_mass_storage]
__composite_unbind+0x4a/0x6f [libcomposite]
composite_unbind+0x12/0x14 [libcomposite]
usb_gadget_remove_driver+0x4f/0x77 [udc_core]
usb_del_gadget_udc+0x52/0xcc [udc_core]
dummy_udc_remove+0x27/0x2c [dummy_hcd]
platform_drv_remove+0x1d/0x31
device_release_driver_internal+0xe9/0x16d
device_release_driver+0x11/0x13
bus_remove_device+0xd2/0xe2
device_del+0x19f/0x221
? selinux_capable+0x22/0x27
platform_device_del+0x21/0x63
platform_device_unregister+0x10/0x1a
cleanup+0x20/0x817 [dummy_hcd]
SyS_delete_module+0x10c/0x197
? ____fput+0xd/0xf
? task_work_run+0x55/0x62
? prepare_exit_to_usermode+0x65/0x75
do_fast_syscall_32+0x86/0xc3
entry_SYSENTER_32+0x4e/0x7c

What happens is that removing the dummy-hcd driver causes the UDC core
to unbind the gadget driver, which it does while holding the udc_lock
mutex. The unbind routine in g_mass_storage tells the main thread to
exit and waits for it to terminate.

But as mentioned above, when the main thread exits it tries to
unregister the mass-storage function driver. Via the composite
framework this ends up calling usb_gadget_unregister_driver(), which
tries to acquire the udc_lock mutex. The result is deadlock.

The simplest way to fix the problem is not to be so clever: The main
thread doesn't have to unregister the function driver. The side
effects won't be so terrible; if the gadget is still attached to a USB
host when the main thread is killed, it will appear to the host as
though the gadget's firmware has crashed -- a reasonably accurate
interpretation, and an all-too-common occurrence for USB mass-storage
devices.

In fact, the code to unregister the driver when the main thread exits
is specific to g-mass-storage; it is not used when f-mass-storage is
included as a function in a larger composite device. Therefore the
entire mechanism responsible for this (the fsg_operations structure
with its ->thread_exits method, the fsg_common_set_ops() routine, and
the msg_thread_exits() callback routine) can all be eliminated. Even
the msg_registered bitflag can be removed, because now the driver is
unregistered in only one place rather than in two places.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
CC: <stable@vger.kernel.org>
Acked-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Acked-by: Michal Nazarewicz <mina86@mina86.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: gadget: mass_storage: set msg_registered after msg registered

If there is no UDC available, the msg register will fail and this
flag will not be set, but the driver is already added into pending
driver list, then the module removal modprobe -r can not remove
the driver from the pending list.

Signed-off-by: Li Jun <jun.li@nxp.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>

usb: f_mass_storage: test whether thread is running before starting another

When binding the function to usb_configuration, check whether the thread
is running before starting another one. Without that, when function
instance is added to multiple configurations, fsg_bing starts multiple
threads with all but the latest one being forgotten by the driver. This
leads to obvious thread leaks, possible lockups when trying to halt the
machine and possible more issues.

This fixes issues with legacy/multi¹ gadget as well as configfs gadgets
when mass_storage function is added to multiple configurations.

This change also simplifies API since the legacy gadgets no longer need
to worry about starting the thread by themselves (which was where bug
in legacy/multi was in the first place).

N.B., this patch doesn’t address adding single mass_storage function
instance to a single configuration twice. Thankfully, there’s no
legitimate reason for such setup plus, if I’m not mistaken, configfs
gadget doesn’t even allow it to be expressed.

¹ I have no example failure though. Conclusion that legacy/multi has
a bug is based purely on me reading the code.

Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Michal Nazarewicz <mina86@mina86.com>
Tested-by: Ivaylo Dimitrov <ivo.g.dimitrov.75@gmail.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: <stable@vger.kernel.org>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>

usb: gadget: composite: remove redundant bcdUSB setting in legacy

Since composite now overwrites bcdUSB for any gadget, remove
setting it in legacy gadgets. All legacy gadgets set 0x0200, the
same as the value additionally set by composite, so there is no
behaviour change.

Signed-off-by: Igor Kotrasinski <i.kotrasinsk@samsung.com>

Rebase onto current balbi/next

Signed-off-by: Krzysztof Opasiak <k.opasiak@samsung.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

usb: gadget: mass_storage: Use static array for luns

This patch replace dynamicly allocated luns array with static one.
This simplifies the code of mass storage function and modules.

Signed-off-by: Krzysztof Opasiak <k.opasiak@samsung.com>
Acked-by: Michal Nazarewicz <mina86@mina86.com>

usb: gadget: mass_storage: allocate and init otg descriptor by otg capabilities

Allocate and initialize usb otg descriptor according to gadget otg
capabilities, add it for each usb configurations. If otg capability
is not defined, keep its original otg descriptor unchanged.

Signed-off-by: Li Jun <jun.li@freescale.com>
Reviewed-by: Roger Quadros <rogerq@ti.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

usb: gadget: remove incorrect __init/__exit annotations

A recent change introduced a link error for the composite
printer gadget driver:

`printer_unbind' referenced in section `.ref.data' of drivers/built-in.o: defined in discarded section `.exit.text' of drivers/built-in.o

Evidently the unbind function should not be marked __exit here,
because it is called through a callback pointer that is not necessarily
discarded, __composite_unbind() is indeed called from the error path of
composite_bind(), which can never work for a built-in driver.

Looking at the surrounding code, I found the same problem in all other
composite gadget drivers in both the bind and unbind functions, as
well as the udc platform driver 'remove' functions. Those will break
if anyone uses the 'unbind' sysfs attribute to detach a device from a
built-in driver.

This patch removes the incorrect annotations from all the gadget
drivers.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Felipe Balbi <balbi@ti.com>

usb: gadget: Gadget directory cleanup - group legacy gadgets

The drivers/usb/gadget directory contains many files.
Files which are related can be distributed into separate directories.
This patch moves the legacy gadgets (i.e. those not using configfs)
into a separate directory.

Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@samsung.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>