This partly reverts 07a18bd7 ("usb gadget: don't save bind callback in
struct usb_composite_driver") and fixes new drivers. The section missmatch
problems was solved by whitelisting bind callback in modpost.
Acked-by: NMichal Nazarewicz <mina86@mina86.com>
Signed-off-by: NSebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: NFelipe Balbi <balbi@ti.com>

usb_gadget_remove_driver() runs through a four-step sequence to shut down
the gadget driver.  For the case of a composite gadget + at91 UDC, this
would look like:

    udc->driver->disconnect(udc->gadget);          // composite_disconnect()
    usb_gadget_disconnect(udc->gadget);            // at91_pullup(gadget, 0)
    udc->driver->unbind(udc->gadget);              // composite_unbind()
    usb_gadget_udc_stop(udc->gadget, udc->driver); // at91_stop()

The UDC driver can receive SETUP packets from the host up until the
point when usb_gadget_disconnect() returns.  On rare occasions, the
gadget driver may see this sequence:

    udc->driver->disconnect(udc->gadget);          // composite_disconnect()
    udc->driver->setup(udc->gadget, &ctrl);        // composite_setup()
    udc->driver->unbind(udc->gadget);              // composite_unbind()

Some gadget drivers, such as composite, assume this will never happen
and crash as a result.

The fix is to quiesce the UDC hardware (via usb_gadget_disconnect)
before running the gadget driver through the disconnect/unbind sequence.
Reviewed-by: NPeter Chen <peter.chen@freescale.com>
Signed-off-by: NKevin Cernekee <cernekee@gmail.com>
Signed-off-by: NFelipe Balbi <balbi@ti.com>

This patch (as1548) fixes a recently-introduced incompatibility
between the UDC core and the dummy-hcd driver.  Commit
8ae8090c (usb: gadget: udc-core: fix
asymmetric calls in remove_driver) moved the usb_gadget_udc_stop()
call in usb_gadget_remove_driver() below the usb_gadget_disconnect()
call.

As a result, usb_gadget_disconnect() gets called at a time when the
gadget driver believes it has been unbound but dummy-hcd believes
it has not.  A nasty error ensues when dummy-hcd calls the gadget
driver's disconnect method a second time.

To fix the problem, this patch moves the gadget driver's unbind
notification after the usb_gadget_disconnect() call.  Now nothing
happens between the two unbind notifications, so nothing goes wrong.
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
Tested-by: NAlexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: NFelipe Balbi <balbi@ti.com>

commit 6d258a4c (usb: gadget: udc-core: stop UDC on device-initiated
disconnect) introduced another case of asymmetric calls when issuing
a device-initiated disconnect. Fix it.
Reported-by: NBen Hutchings <ben@decadent.org.uk>
Signed-off-by: NFelipe Balbi <balbi@ti.com>

During modprobe of gadget driver, pullup is called after
udc_start. In order to make the exit path symmetric when
removing a gadget driver, call pullup before ->udc_stop.

This is needed to avoid issues with PM where udc_stop
disables the module completely (put IP in reset state,
cut functional and interface clocks, and so on), which
prevents us from accessing the IP's address space,
thus creating the possibility of an abort exception
when we try to access IP's address space after clocks
are off.

Cc: stable@vger.kernel.org
Signed-off-by: NPartha Basak <p-basak2@ti.com>
Signed-off-by: NKishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: NFelipe Balbi <balbi@ti.com>

When we want to do device-initiated disconnect,
let's make sure we stop the UDC in order to
e.g. allow lower power states to be achieved by
turning off unnecessary clocks and/or stoping
PHYs.

When reconnecting, call ->udc_start() again to
make sure UDC is reinitialized.

Cc: stable@vger.kernel.org
Signed-off-by: NFelipe Balbi <balbi@ti.com>

such utilities are currently duplicated on all UDC
drivers basically with the same structure. Let's group
all implementations into one generic implementation
and get rid of that duplication.
Signed-off-by: NFelipe Balbi <balbi@ti.com>

This commit replaces usb_gadget's is_dualspeed field with
a max_speed field.

[ balbi@ti.com : Fixed DWC3 driver ]
Signed-off-by: NMichal Nazarewicz <mina86@mina86.com>
Signed-off-by: NFelipe Balbi <balbi@ti.com>

Those are simply giving information about the current
state of the UDC, nothing really fancy. We can let
everybody read those.
Signed-off-by: NFelipe Balbi <balbi@ti.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

usb_gadget_disconnect() is responsible of removing
data pullups. Before doing that we must, first, tell
gadget driver we're disconnecting (by calling disconnect
method on gadget driver structure), unbind the gadget
driver and stop the controller.
Signed-off-by: NFelipe Balbi <balbi@ti.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

We should not be using dev_get_drvdata() because we
never call dev_set_drvdata(). Let's use container_of()
as all other sysfs attributes.
Signed-off-by: NFelipe Balbi <balbi@ti.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

We should not be using dev_get_drvdata() because we
never call dev_set_drvdata(). Let's use container_of()
as all other sysfs attributes.
Signed-off-by: NFelipe Balbi <balbi@ti.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

In a few places in the kernel, the code prints
a human-readable USB device speed (eg. "high speed").
This involves a switch statement sometimes wrapped
around in ({ ... }) block leading to code repetition.

To mitigate this issue, this commit introduces
usb_speed_string() function, which returns
a human-readable name of provided speed.

It also changes a few places switch was used to use
this new function.  This changes a bit the way the
speed is printed in few instances at the same time
standardising it.
Signed-off-by: NMichal Nazarewicz <mina86@mina86.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

This was somehow forgotten.
Signed-off-by: NSebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: NFelipe Balbi <balbi@ti.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

udc_start() should only trigger the internal state machine and make
minimal house keeping. Before that call udc-core calls the bind()
callback and after the callback the pullup().

udc_stop() is simillar, udc-core calls pullup(), unbind() and finally
udc_stop().
Signed-off-by: NSebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: NFelipe Balbi <balbi@ti.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

this class will be used to abstract away several of the duplicated
operations scattered among the USB gadget controller drivers.

Later, we can add an atomic notifier to tell interested drivers about
what's happening with the controller. Notifications such as suspend,
resume, enumerated, etc. will be useful, at a minimum, for implementing
usb charger detection.

As part of the converting process usb_gadget_probe_driver() is no longer
part of each udc but pushed into the ->stap() callback. The same for his
couterpart.

The core is currently set explicit to 'n'. It will be changed to 'y' once
all users are converted since it provides functions which clash with
other drivers.
Signed-off-by: NFelipe Balbi <balbi@ti.com>
Signed-off-by: NSebastian Andrzej Siewior <bigeasy@linutronix.de>
Acked-by: NMichal Nazarewicz <mina86@mina86.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>