Finish the rx_max/tx_max setup by flushing buffers and
informing usbnet about the changes.  This way, the settings
can be modified while the netdev is up and running.
Signed-off-by: NBjørn Mork <bjorn@mork.no>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Now that we have split out the part of the device setup
which MUST be done with the data interface in altsetting 0,
we can delay the rest of the initialization. This allows us
to move some of post-init buffer size config from bind to
the appropriate setup function.

The purpose of this refactoring is to collect all code
adjusting the rx_max and tx_max buffers in one place, so
that it is easier to call it from multiple call sites.
Signed-off-by: NBjørn Mork <bjorn@mork.no>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Split the parts of setup dealing with device initialization from
parts just setting defaults for attributes which might be
changed after initialization.

Some commands of the device initialization are only allowed when
the data interface is in its disabled altsetting, so we must
separate them out of we are to allow rerunning parts of setup.
Signed-off-by: NBjørn Mork <bjorn@mork.no>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Split out the part of setup dealing with updating the rx_max
and tx_max buffer sizes so that this code can be reused for
dynamically updating the limits.
Signed-off-by: NBjørn Mork <bjorn@mork.no>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The NCM class match in the cdc_mbim driver is confusing and
cause unexpected behaviour. The USB core guarantees that a
USB interface is in altsetting 0 when probing starts. This
means that devices implementing a NCM 1.0 backwards
compatible MBIM function (a "NCM/MBIM function") always hit
the NCM entry in the cdc_mbim driver match table. Such
functions will never match any of the MBIM entries.

This causes unexpeced behaviour for cases where the NCM and
MBIM entries are differet, which is currently the case for
all except Ericsson devices.

Improve the probing of NCM/MBIM functions by looking up the
device again in the cdc_mbim match table after switching to
the MBIM identity.

The shared altsetting selection is updated to better
accommodate the new probing logic, returning the preferred
altsetting for the control interface instead of the data
interface. The control interface altsetting update is moved
to the cdc_mbim driver. It is never necessary to change the
control interface altsetting for NCM.

Cc: Greg Suarez <gsuarez@smithmicro.com>
Reported by: Yu-an Shih <yshih@nvidia.com>
Signed-off-by: NBjørn Mork <bjorn@mork.no>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Commit 4d619f62 ("net: cdc_ncm: no point in filling up the NTBs
if we send ZLPs") changed the padding logic for devices with the ZLP
flag set.  This meant that frames of any size will be sent without
additional padding, except for the single byte added if the size is
a multiple of the USB packet size. But if the unpadded size is
identical to the maximum frame size, and the maximum size is a
multiplum of the USB packet size, then this one-byte padding will
overflow the buffer.

Prevent padding if already at maximum frame size, letting usbnet
transmit a ZLP instead in this case.

Fixes: 4d619f62 ("net: cdc_ncm: no point in filling up the NTBs if we send ZLPs")
Reported by: Yu-an Shih <yshih@nvidia.com>
Signed-off-by: NBjørn Mork <bjorn@mork.no>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

According to "Universal Serial Bus Communications Class Subclass
Specification for Mobile Broadband Interface Model, Revision 1.0,
Errata-1" published by USB-IF, the wMTU field of the MBIM extended
functional descriptor indicates the operator preferred MTU for IP data
streams.

This patch modifies cdc_ncm_setup to ensure that the MTU value set on
the usbnet device does not exceed the operator preferred MTU indicated
by wMTU if the MBIM device exposes a MBIM extended functional
descriptor.
Signed-off-by: NBen Chan <benchan@chromium.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This is a context modified revert of commit 6a9612e2
("net: cdc_ncm: remove ncm_parm field") which introduced
a NCM specification violation, causing setup errors for
some devices. These errors resulted in the device and
host disagreeing about shared settings, with complete
failure to communicate as the end result.

The NCM specification require that many of the NCM specific
control reuests are sent only while the NCM Data Interface
is in alternate setting 0. Reverting the commit ensures that
we follow this requirement.

Fixes: 6a9612e2 ("net: cdc_ncm: remove ncm_parm field")
Reported-and-tested-by: NPasi Kärkkäinen <pasik@iki.fi>
Reported-by: NThomas Schäfer <tschaefer@t-online.de>
Signed-off-by: NBjørn Mork <bjorn@mork.no>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

None of these files are actually using any __init type directives
and hence don't need to include <linux/init.h>.   Most are just a
left over from __devinit and __cpuinit removal, or simply due to
code getting copied from one driver to the next.

This covers everything under drivers/net except for wireless, which
has been submitted separately.
Signed-off-by: NPaul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This is harmless but cdc_ncm_setup() returns negative error codes
truncated to u8 values.  There is only one caller and treats all
non-zero returns as errors but doesn't store the the return code.  So
the code works correctly but it's messy and upsets the static checkers.
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Remove device IDs of NCM-like (but not NCM-conformant) devices, that are
handled by the huawwei_cdc_ncm driver now.
Signed-off-by: NEnrico Mioso <mrkiko.rs@gmail.com>
Signed-off-by: NBjørn Mork <bjorn@mork.no>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Some drivers implementing NCM-like protocols, may re-use those functions, as is
the case in the huawei_cdc_ncm driver.
Export them via EXPORT_SYMBOL_GPL, in accordance with how other functions have
been exported.
Signed-off-by: NEnrico Mioso <mrkiko.rs@gmail.com>
Signed-off-by: NBjørn Mork <bjorn@mork.no>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

There are MBIM devices out there reporting

  dwNtbInMaxSize=2048 dwNtbOutMaxSize=2048

and since the spec require a datagram max size of at least
2048, this means that a full sized datagram will never fit.

Still, sending larger NTBs than the device supports is not
going to help.  We do not have any other options than either
 a) refusing to bindi, or
 b) respect the insanely low value.

Alternative b will at least make these devices work, so go
for it.

Cc: Alexey Orishko <alexey.orishko@gmail.com>
Signed-off-by: NBjørn Mork <bjorn@mork.no>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Make it a bit easier for users to figure out what goes
wrong when bind fails.

Cc: Alexey Orishko <alexey.orishko@gmail.com>
Signed-off-by: NBjørn Mork <bjorn@mork.no>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Most setup errors are ignored to ensure maximum firmware
compatibilty.  But GET_NTB_PARAMETERS and the functional
descriptors are required.  Use proper error codes and
log level if these fail.

Cc: Alexey Orishko <alexey.orishko@gmail.com>
Signed-off-by: NBjørn Mork <bjorn@mork.no>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Rewriting the "set max datagram" part of dc_ncm_setup to
separate the selection and validatation of the size from
the code which optionally informs the device of this
value.  This ensures that we use the correct value
regardless of device support for the get and set commands.

Removing some of the many indent levels while doing this
to make the code more readable.

Cc: Alexey Orishko <alexey.orishko@gmail.com>
Signed-off-by: NBjørn Mork <bjorn@mork.no>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Converting the constants used in these comparisons at build
time instead of converting the variables for every received
frame at run time.

Cc: Alexey Orishko <alexey.orishko@gmail.com>
Signed-off-by: NBjørn Mork <bjorn@mork.no>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

These signatures are well known bit patterns, mostly made up
of ascii characters.  Mentally parsing works best if they
are printed in hex.

Cc: Alexey Orishko <alexey.orishko@gmail.com>
Signed-off-by: NBjørn Mork <bjorn@mork.no>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Take advantage of standard device name prefixing and
netdevice msglvl control where possible.

Cc: Alexey Orishko <alexey.orishko@gmail.com>
Signed-off-by: NBjørn Mork <bjorn@mork.no>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Fix cut'n'paste typo.  Log the bogus length and not the
irrelevant signature.

Cc: Alexey Orishko <alexey.orishko@gmail.com>
Signed-off-by: NBjørn Mork <bjorn@mork.no>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

usbnet use the hard_mtu value for sizing the tx queue and nothing
else.  We will be transmitting buffers of up to tx_max size, so
that's the proper value to give usbnet.

The individual datagram size is completely irrelevant here.

Cc: Alexey Orishko <alexey.orishko@gmail.com>
Signed-off-by: NBjørn Mork <bjorn@mork.no>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

No need to keep this code duplicated from usbnet.

Cc: Alexey Orishko <alexey.orishko@gmail.com>
Signed-off-by: NBjørn Mork <bjorn@mork.no>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

These functions were merely wrappers around the usbnet
variants.  Remove them.

Cc: Alexey Orishko <alexey.orishko@gmail.com>
Signed-off-by: NBjørn Mork <bjorn@mork.no>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Padding NTBs to max size is part of the support for devices
optimizing their DMA transfers. This optimization depends on
max sized NTBs not being ZLP terminated. So we are much better
off dropping the padding if we are going to send a ZLP anyway.

Cc: Alexey Orishko <alexey.orishko@gmail.com>
Signed-off-by: NBjørn Mork <bjorn@mork.no>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The probed interface must be the master/control interface of the
function.  Make this explicit and simplify redundant tests.

Cc: Alexey Orishko <alexey.orishko@gmail.com>
Signed-off-by: NBjørn Mork <bjorn@mork.no>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

header_desc was completely unused and union_desc was never used
outside cdc_ncm_bind_common.

Cc: Alexey Orishko <alexey.orishko@gmail.com>
Signed-off-by: NBjørn Mork <bjorn@mork.no>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We need to inform the device about the *new* value, not the
old one.

Cc: Alexey Orishko <alexey.orishko@gmail.com>
Signed-off-by: NBjørn Mork <bjorn@mork.no>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Moving the call to cdc_ncm_setup() after the endpoint
setup removes the last remaining reference to ncm_parm
outside cdc_ncm_setup.

Collecting all the ncm_parm based calculations in
cdc_ncm_setup improves readability.

Cc: Alexey Orishko <alexey.orishko@gmail.com>
Signed-off-by: NBjørn Mork <bjorn@mork.no>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

These fields are only used to prevent printing the same speeds
multiple times if we receive multiple identical speed notifications.

The value of these printk's is questionable, and even more so when
we filter out some of the notifications sent us by the firmware. If
we are going to print any of these, then we should print them all.

Removing little used fields is a bonus.

Cc: Alexey Orishko <alexey.orishko@gmail.com>
Signed-off-by: NBjørn Mork <bjorn@mork.no>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We already use the usbnet udev field everywhere this could have
been used.

Cc: Alexey Orishko <alexey.orishko@gmail.com>
Signed-off-by: NBjørn Mork <bjorn@mork.no>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Too many pointers back and forth are likely to confuse developers,
creating subtle bugs whenever we forget to syncronize them all.

As a usbnet driver, we should stick with the standard struct
usbnet fields as much as possible.  The netdevice is one such
field.

Cc: Greg Suarez <gsuarez@smithmicro.com>
Cc: Alexey Orishko <alexey.orishko@gmail.com>
Signed-off-by: NBjørn Mork <bjorn@mork.no>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

No need to duplicate stuff already in the common usbnet
struct.  We still need to keep our special find_endpoints
function because we need explicit control over the selected
altsetting.

Cc: Alexey Orishko <alexey.orishko@gmail.com>
Signed-off-by: NBjørn Mork <bjorn@mork.no>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This is always a duplicate of the "control" field. It causes
confusion wrt intf_data updates and cleanups.

Cc: Alexey Orishko <alexey.orishko@gmail.com>
Signed-off-by: NBjørn Mork <bjorn@mork.no>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We can avoid the costly division for the common case where
we pad the frame to tx_max size as long as we ensure that
tx_max is either the device specified dwNtbOutMaxSize or not
a multiplum of wMaxPacketSize.

Using the preconverted 'maxpacket' field avoids converting
wMaxPacketSize to CPU endianness for every transmitted frame

And since we only will hit the one byte padding rule for short
frames, we can drop testing the skb for tailroom.

The change means that tx_max now represents the real maximum
skb size, enabling us to allocate the correct size instead of
always making room for one extra byte.

Cc: Alexey Orishko <alexey.orishko@gmail.com>
Signed-off-by: NBjørn Mork <bjorn@mork.no>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Use the introduced usbnet_link_change to handle link change.
Signed-off-by: NMing Lei <ming.lei@canonical.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Receiving unhandled notifications is most certainly not an error
and should not be logged as one.  Knowing that the device sends
notifications we don't handle is useful for developers, but there
is very little a user can do about this.  The message is therefore
just annoying noise to most users with devices sending unhandled
notifications like e.g. USB_CDC_NOTIFY_RESPONSE_AVAILABLE

Cc: Alexey Orishko <alexey.orishko@stericsson.com>
Signed-off-by: NBjørn Mork <bjorn@mork.no>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

return -ENOMEM instead if kzalloc of cdc_ncm_ctx structure is failed.

and also remove the comparision of ctx structure with NULL and make
it as !ctx.
Signed-off-by: NDevendra Naga <devendra.aaru@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

commit bd329e12 ("net: cdc_ncm: do not bind to NCM compatible MBIM devices")
introduced a new policy, preferring MBIM for dual NCM/MBIM functions if
the cdc_mbim driver was enabled.  This caused a regression for users
wanting to use NCM.

Devices implementing NCM backwards compatibility according to section
3.2 of the MBIM v1.0 specification allow either NCM or MBIM on a single
USB function, using different altsettings.  The cdc_ncm and cdc_mbim
drivers will both probe such functions, and must agree on a common
policy for selecting either MBIM or NCM.  Until now, this policy has
been set at build time based on CONFIG_USB_NET_CDC_MBIM.

Use a module parameter to set the system policy at runtime, allowing the
user to prefer NCM on systems with the cdc_mbim driver.

Cc: Greg Suarez <gsuarez@smithmicro.com>
Cc: Alexey Orishko <alexey.orishko@stericsson.com>
Reported-by: NGeir Haatveit <nospam@haatveit.nu>
Reported-by: NTommi Kyntola <kynde@ts.ray.fi>
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=54791Signed-off-by: NBjørn Mork <bjorn@mork.no>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Tag all Huawei NCM devices as WWAN modems, as we don't know of any which
are not.  This is necessary for userspace clients to know that the device
requires further setup on e.g. an AT-capable serial ports before
connectivity is available.
Signed-off-by: NBjørn Mork <bjorn@mork.no>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

commit bd329e12 ("net: cdc_ncm: do not bind to NCM compatible MBIM devices")
added a test for a CDC MBIM altsetting, implementing the cdc_ncm part of
MBIM backward compatibility support.  This intentionally made the driver
behave differently for CDC NCM devices with 2 alternate settings for the
Communication interface, depending on whether or not CONFIG_USB_NET_CDC_MBIM
was enabled.  This is correct iff alternate setting #1 really *is* a MBIM
setting.  If not, then NCM probing will use a different altsetting than before,
possibly causing probing failures depending on CONFIG_USB_NET_CDC_MBIM.

Fix by setting the altsetting back to default after the test, restoring the
previous behaviour for non MBIM devices.

This bug causes probing of Huawei E3276 devices to fail when the MBIM driver
is enabled, because these devices have a second alternate setting with no CDC
functional descriptors.

Cc: Greg Suarez <gsuarez@smithmicro.com>
Cc: Alexey Orishko <alexey.orishko@stericsson.com>
Reported-and-tested-by: NJonathan A. <yo.natan@hotmail.com>
Signed-off-by: NBjørn Mork <bjorn@mork.no>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>