USB: serial: return errors from break handling

Start propagating errors to user space when setting the break state
fails.

This will be used by follow-on changes to also report when a driver or
device does not support break control.

Tested-by: Corey Minyard <cminyard@mvista.com>
Signed-off-by: Johan Hovold <johan@kernel.org>

usb: serial: Make ->set_termios() old ktermios const

There should be no reason to adjust old ktermios which is going to get
discarded anyway.

Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20220816115739.10928-8-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

USB: serial: ch341: fix disabled rx timer on older devices

At least one older CH341 appears to have the RX timer enable bit
inverted so that setting it disables the RX timer and prevents the FIFO
from emptying until it is full.

Only set the RX timer enable bit for devices with version newer than
0x27 (even though this probably affects all pre-0x30 devices).

Reported-by: Jonathan Woithe <jwoithe@just42.net>
Tested-by: Jonathan Woithe <jwoithe@just42.net>
Link: https://lore.kernel.org/r/Ys1iPTfiZRWj2gXs@marvin.atrad.com.au
Fixes: 4e46c410e050 ("USB: serial: ch341: reinitialize chip on reconfiguration")
Cc: stable@vger.kernel.org # 4.10
Signed-off-by: Johan Hovold <johan@kernel.org>

USB: serial: ch341: fix lost character on LCR updates

Disable LCR updates for pre-0x30 devices which use a different (unknown)
protocol for line control and where the current register write causes
the next received character to be lost.

Note that updating LCR using the INIT command has no effect on these
devices either.

Reported-by: Jonathan Woithe <jwoithe@just42.net>
Tested-by: Jonathan Woithe <jwoithe@just42.net>
Link: https://lore.kernel.org/r/Ys1iPTfiZRWj2gXs@marvin.atrad.com.au
Fixes: 4e46c410e050 ("USB: serial: ch341: reinitialize chip on reconfiguration")
Fixes: 55fa15b5987d ("USB: serial: ch341: fix baud rate and line-control handling")
Cc: stable@vger.kernel.org # 4.10
Signed-off-by: Johan Hovold <johan@kernel.org>

Revert "USB: serial: ch341: add new Product ID for CH341A"

This reverts commit 46ee4abb10a07bd8f8ce910ee6b4ae6a947d7f63.

CH341 has Product ID 0x5512 in EPP/MEM mode which is used for
I2C/SPI/GPIO interfaces. In asynchronous serial interface mode
CH341 has PID 0x5523 which is already in the table.

Mode is selected by corresponding jumper setting.

Signed-off-by: Dmytro Bagrii <dimich.dmb@gmail.com>
Link: https://lore.kernel.org/r/20220210164137.4376-1-dimich.dmb@gmail.com
Link: https://lore.kernel.org/r/YJ0OCS/sh+1ifD/q@hovoldconsulting.com
Cc: stable@vger.kernel.org
Signed-off-by: Johan Hovold <johan@kernel.org>

USB: serial: ch341: add support for GW Instek USB2.0-Serial devices

Programmable lab power supplies made by GW Instek, such as the
GPP-2323, have a USB port exposing a serial port to control the device.

Stringing the supplied Windows driver, references to the ch341 chip are
found. Binding the existing ch341 driver to the VID/PID of the GPP-2323
("GW Instek USB2.0-Serial" as per the USB product name) works out of the
box, communication and control is now possible.

This patch should work with any GPP series power supply due to
similarities in the product line.

Signed-off-by: Stephan Brunner <s.brunner@stephan-brunner.net>
Link: https://lore.kernel.org/r/4a47b864-0816-6f6a-efee-aa20e74bcdc6@stephan-brunner.net
Cc: stable@vger.kernel.org
Signed-off-by: Johan Hovold <johan@kernel.org>

USB: serial: ch314: use usb_control_msg_recv()

usb_control_msg_recv() is a new wrapper function for usb_control_msg()
that has error checks for short reads. This function also accepts data
buffer on stack. Hence use this function to simplify error handling for
short reads. Short reads will now get reported as -EREMOTEIO with no
indication of how short the transfer was.

Signed-off-by: Himadri Pandya <himadrispandya@gmail.com>
Link: https://lore.kernel.org/r/20211001065720.21330-2-himadrispandya@gmail.com
[ johan: fix quirk-detection breakage, style changes ]
Signed-off-by: Johan Hovold <johan@kernel.org>

Revert "USB: serial: ch341: fix character loss at high transfer rates"

This reverts commit 3c18e9baee0ef97510dcda78c82285f52626764b.

These devices do not appear to send a zero-length packet when the
transfer size is a multiple of the bulk-endpoint max-packet size. This
means that incoming data may not be processed by the driver until a
short packet is received or the receive buffer is full.

Revert back to using endpoint-sized receive buffers to avoid stalled
reads.

Reported-by: Paul Größel <pb.g@gmx.de>
Link: https://bugzilla.kernel.org/show_bug.cgi?id=214131
Fixes: 3c18e9baee0e ("USB: serial: ch341: fix character loss at high transfer rates")
Cc: stable@vger.kernel.org
Cc: Willy Tarreau <w@1wt.eu>
Link: https://lore.kernel.org/r/20210824121926.19311-1-johan@kernel.org
Signed-off-by: Johan Hovold <johan@kernel.org>

USB: serial: ch341: fix character loss at high transfer rates

The chip supports high transfer rates, but with the small default buffers
(64 bytes read), some entire blocks are regularly lost. This typically
happens at 1.5 Mbps (which is the default speed on Rockchip devices) when
used as a console to access U-Boot where the output of the "help" command
misses many lines and where "printenv" mangles the environment.

The FTDI driver doesn't suffer at all from this. One difference is that
it uses 512 bytes rx buffers and 256 bytes tx buffers. Adopting these
values completely resolved the issue, even the output of "dmesg" is
reliable. I preferred to leave the Tx value unchanged as it is not
involved in this issue, while a change could increase the risk of
triggering the same issue with other devices having too small buffers.

I verified that it backports well (and works) at least to 5.4. It's of
low importance enough to be dropped where it doesn't trivially apply
anymore.

Cc: stable@vger.kernel.org
Signed-off-by: Willy Tarreau <w@1wt.eu>
Link: https://lore.kernel.org/r/20210724152739.18726-1-w@1wt.eu
Signed-off-by: Johan Hovold <johan@kernel.org>

USB: serial: ch341: add new Product ID

Add PID for CH340 that's found on cheap programmers.

The driver works flawlessly as soon as the new PID (0x9986) is added to it.
These look like ANU232MI but ship with a ch341 inside. They have no special
identifiers (mine only has the string "DB9D20130716" printed on the PCB and
nothing identifiable on the packaging. The merchant i bought it from
doesn't sell these anymore).

the lsusb -v output is:
Bus 001 Device 009: ID 9986:7523
Device Descriptor:
bLength 18
bDescriptorType 1
bcdUSB 1.10
bDeviceClass 255 Vendor Specific Class
bDeviceSubClass 0
bDeviceProtocol 0
bMaxPacketSize0 8
idVendor 0x9986
idProduct 0x7523
bcdDevice 2.54
iManufacturer 0
iProduct 0
iSerial 0
bNumConfigurations 1
Configuration Descriptor:
bLength 9
bDescriptorType 2
wTotalLength 0x0027
bNumInterfaces 1
bConfigurationValue 1
iConfiguration 0
bmAttributes 0x80
(Bus Powered)
MaxPower 96mA
Interface Descriptor:
bLength 9
bDescriptorType 4
bInterfaceNumber 0
bAlternateSetting 0
bNumEndpoints 3
bInterfaceClass 255 Vendor Specific Class
bInterfaceSubClass 1
bInterfaceProtocol 2
iInterface 0
Endpoint Descriptor:
bLength 7
bDescriptorType 5
bEndpointAddress 0x82 EP 2 IN
bmAttributes 2
Transfer Type Bulk
Synch Type None
Usage Type Data
wMaxPacketSize 0x0020 1x 32 bytes
bInterval 0
Endpoint Descriptor:
bLength 7
bDescriptorType 5
bEndpointAddress 0x02 EP 2 OUT
bmAttributes 2
Transfer Type Bulk
Synch Type None
Usage Type Data
wMaxPacketSize 0x0020 1x 32 bytes
bInterval 0
Endpoint Descriptor:
bLength 7
bDescriptorType 5
bEndpointAddress 0x81 EP 1 IN
bmAttributes 3
Transfer Type Interrupt
Synch Type None
Usage Type Data
wMaxPacketSize 0x0008 1x 8 bytes
bInterval 1

Signed-off-by: Niv Sardi <xaiki@evilgiggle.com>
Cc: stable@vger.kernel.org
Signed-off-by: Johan Hovold <johan@kernel.org>

USB: serial: make remove callback return void

All usb_serial drivers return 0 in their remove callbacks and driver
core ignores the value returned by usb_serial_device_remove(). So change
the remove callback to return void and return 0 unconditionally in
usb_serial_device_remove().

Signed-off-by: Uwe Kleine-König <uwe@kleine-koenig.org>
Link: https://lore.kernel.org/r/20210208143149.963644-2-uwe@kleine-koenig.org
Signed-off-by: Johan Hovold <johan@kernel.org>

USB: serial: ch341: sort device-id entries

Keep the device-id entries sorted to make it easier to add new ones in
the right spot.

Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: stable@vger.kernel.org
Signed-off-by: Johan Hovold <johan@kernel.org>

USB: serial: ch341: add new Product ID for CH341A

Add PID for CH340 that's found on a ch341 based Programmer made by keeyees.
The specific device that contains the serial converter is described
here: http://www.keeyees.com/a/Products/ej/36.html

The driver works flawlessly as soon as the new PID (0x5512) is added to
it.

Signed-off-by: Jan-Niklas Burfeind <kernel@aiyionpri.me>
Cc: stable@vger.kernel.org
Signed-off-by: Johan Hovold <johan@kernel.org>

USB: serial: ch341: fix missing simulated-break margin

On devices which do not support break signalling a break condition is
simulated by sending a NUL byte at the lowest possible speed. The break
condition will be 9 bit periods long (start bit and eight data bits),
but the transmission itself also includes the stop bit.

Add the missing safety margin of one bit which is intended to account
for timing differences, and fix up the corresponding comment.

Signed-off-by: Michael Hanselmann <public@hansmi.ch>
Link: https://lore.kernel.org/r/9909b288-294d-16b9-9f14-51eb79c63b6c@msgid.hansmi.ch
[ johan: amend commit message ]
Signed-off-by: Johan Hovold <johan@kernel.org>

USB: serial: ch341: simulate break condition if not supported

A subset of all CH341 devices don't support a real break condition. This
fact is already used in the "ch341_detect_quirks" function. With this
change a quirk is implemented to simulate a break condition by
temporarily lowering the baud rate and sending a NUL byte.

The primary drawbacks of this approach are that the duration of the
break can't be controlled by userland and that data incoming during
a simulated break is corrupted.

The "TTY_DRIVER_HARDWARE_BREAK" serial driver flag was investigated as
an alternative. It's a driver-wide flag and would've required
significant changes to the serial and USB-serial driver frameworks to
expose it for individual USB-serial adapters.

Tested by sending a break condition and watching the TX pin using an
oscilloscope.

Signed-off-by: Michael Hanselmann <public@hansmi.ch>
Link: https://lore.kernel.org/r/f34a9b6e-ec2a-0873-e97b-2d5b2170e2ff@msgid.hansmi.ch
[ johan: condense info message ]
Signed-off-by: Johan Hovold <johan@kernel.org>

USB: serial: ch341: add min and max line-speed macros

The line-speed algorithm clamps the requested value to the supported
range instead of bailing out on unsupported values.

Provide min and max macros and indicate how they are derived instead of
hardcoding the limits.

Note that the algorithm depends on the minimum rate (45.78 bps)
being rounded up (and the maximum rate being rounded down) to avoid
special casing.

Suggested-by: Michael Hanselmann <public@hansmi.ch>
Link: https://lore.kernel.org/r/20200630095756.GZ3334@localhost
Signed-off-by: Johan Hovold <johan@kernel.org>

USB: serial: ch341: name prescaler, divisor registers

Add constants for the prescaler and divisor registers. Document and
name register 0x25, and put the LCR define to more use.

The 0x25 register (CH341_REG_LCR2) is only used by CH341 chips before
version 0x30 and is involved in configuring the line control parameters.
It's not known to the author whether there any such chips in the wild,
and Linux' ch341 driver never supported them. For chip version 0x30 and
above the 0x25 register is always set to zero. The alternative would've
been to not set the register at all, but that may have unintended
effects.

Signed-off-by: Michael Hanselmann <public@hansmi.ch>
Link: https://lore.kernel.org/r/2e80916d-1be8-dc0f-abf9-adc0feea1803@msgid.hansmi.ch
[ johan: fix up comment ]
Signed-off-by: Johan Hovold <johan@kernel.org>

USB: serial: ch341: add new Product ID for CH340

Add PID for CH340 that's found on some ESP8266 dev boards made by
LilyGO. The specific device that contains such serial converter can be
seen here: https://github.com/LilyGO/LILYGO-T-OI.

Apparently, it's a regular CH340, but I've confirmed with others that
also bought this board that the PID found on this device (0x7522)
differs from other devices with the "same" converter (0x7523).
Simply adding its PID to the driver and rebuilding it made it work
as expected.

Signed-off-by: Igor Moura <imphilippini@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: Johan Hovold <johan@kernel.org>

USB: serial: ch341: fix lockup of devices with limited prescaler

Michael Hanselmann reports that

[a] subset of all CH341 devices stop responding to bulk
transfers, usually after the third byte, when the highest
prescaler bit (0b100) is set. There is one exception, namely a
prescaler of exactly 0b111 (fact=1, ps=3).

Fix this by forcing a lower base clock (fact = 0) whenever needed.

This specifically makes the standard rates 110, 134 and 200 bps work
again with these devices.

Fixes: 35714565089e ("USB: serial: ch341: reimplement line-speed handling")
Cc: stable <stable@vger.kernel.org> # 5.5
Reported-by: Michael Hanselmann <public@hansmi.ch>
Link: https://lore.kernel.org/r/20200514141743.GE25962@localhost
Signed-off-by: Johan Hovold <johan@kernel.org>

USB: serial: ch341: add basis for quirk detection

A subset of CH341 devices does not support all features, namely the
prescaler is limited to a reduced precision and there is no support for
sending a RS232 break condition. This patch adds a detection function
which will be extended to set quirk flags as they're implemented.

The author's affected device has an imprint of "340" on the
turquoise-colored plug, but not all such devices appear to be affected.

Signed-off-by: Michael Hanselmann <public@hansmi.ch>
Link: https://lore.kernel.org/r/1e1ae0da6082bb528a44ef323d4e1d3733d38858.1585697281.git.public@hansmi.ch
[ johan: use long type for quirks; rephrase and use port device for
messages; handle short reads; set quirk flags directly in
helper function ]
Cc: stable <stable@vger.kernel.org> # 5.5
Signed-off-by: Johan Hovold <johan@kernel.org>

USB: serial: ch341: fix receiver regression

While assumed not to make a difference, not using the factor-2 prescaler
makes the receiver more susceptible to errors.

Specifically, there have been reports of problems with devices that
cannot generate a 115200 rate with a smaller error than 2.1% (e.g.
117647 bps). But this can also be reproduced with a low-speed RS232
tranceiver at 115200 when the input rate matches the nominal rate.

So whenever possible, enable the factor-2 prescaler and halve the
divisor in order to use settings closer to that of the previous
algorithm.

Fixes: 35714565089e ("USB: serial: ch341: reimplement line-speed handling")
Cc: stable <stable@vger.kernel.org> # 5.5
Reported-by: Jakub Nantl <jn@forever.cz>
Tested-by: Jakub Nantl <jn@forever.cz>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Johan Hovold <johan@kernel.org>

USB: serial: ch341: handle unbound port at reset_resume

Check for NULL port data in reset_resume() to avoid dereferencing a NULL
pointer in case the port device isn't bound to a driver (e.g. after a
failed control request at port probe).

Fixes: 1ded7ea47b88 ("USB: ch341 serial: fix port number changed after resume")
Cc: stable <stable@vger.kernel.org> # 2.6.30
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Johan Hovold <johan@kernel.org>

USB: serial: ch341: reimplement line-speed handling

The current ch341 divisor algorithm was known to give inaccurate results
for certain higher line speeds. Jonathan Olds <jontio@i4free.co.nz>
investigated this, determined the basic equations used to derive the
divisors and confirmed them experimentally [1].

The equations Jonathan used could be generalised further to:

baudrate = 48000000 / (2^(12 - 3 * ps - fact) * div), where

0 <= ps <= 3,
0 <= fact <= 1,
2 <= div <= 256 if fact = 0, or
9 <= div <= 256 if fact = 1

which will also give better results for lower rates.

Notably the error is reduced for the following standard rates:

1152000 (4.0% instead of 15% error)
921600 (0.16% instead of -7.5% error)
576000 (-0.80% instead of -5.6% error)
200 (0.16% instead of -0.69% error)
134 (-0.05% instead of -0.63% error)
110 (0.03% instead of -0.44% error)

but also for many non-standard ones.

The current algorithm also suffered from rounding issues (e.g.
requesting 2950000 Bd resulted in a rate of 2 MBd instead of 3 MBd and
thus a -32% instead of 1.7% error).

The new algorithm was inspired by the current vendor driver even if that
one only handles two higher rates that require fact=1 by hard coding the
corresponding divisors [2].

Michael Dreher <michael@5dot1.de> also did a similar generalisation of
Jonathan's work and has published his results with a very good summary
that provides further insights into how this device works [3].

[1] https://lkml.kernel.org/r/000001d51f34$bad6afd0$30840f70$@co.nz
[2] http://www.wch.cn/download/CH341SER_LINUX_ZIP.html
[3] https://github.com/nospam2000/ch341-baudrate-calculation

Reported-by: Jonathan Olds <jontio@i4free.co.nz>
Tested-by: Jonathan Olds <jontio@i4free.co.nz>
Cc: Michael Dreher <michael@5dot1.de>
Signed-off-by: Johan Hovold <johan@kernel.org>

USB: serial: ch341: fix type promotion bug in ch341_control_in()

The "r" variable is an int and "bufsize" is an unsigned int so the
comparison is type promoted to unsigned. If usb_control_msg() returns a
negative that is treated as a high positive value and the error handling
doesn't work.

Fixes: 2d5a9c72d0c4 ("USB: serial: ch341: fix control-message error handling")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Johan Hovold <johan@kernel.org>

USB: serial: fix module-license macros

Several GPL-2.0 drivers used "GPL" rather than "GPL v2" in their
MODULE_LICENSE macros; fix the macros to match the licenses.

Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

USB: serial: 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.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Johan Hovold <johan@kernel.org>
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: serial: ch341: change initial line-control settings

Some CH340 devices appear unable to change the initial LCR settings, so
set a sane 8N1 default during probe to enable basic support for such
devices.

Also drop a redundant LCR read during device initialisation.

Signed-off-by: Johan Hovold <johan@kernel.org>

USB: serial: ch341: rename LCR variable in set_termios

Rename the line-control-register variable in set_termios to "lcr" and
use u8 type to match the shadow register.

Signed-off-by: Johan Hovold <johan@kernel.org>

USB: serial: ch341: rename modem-status register

Rename the shadow modem-status register currently named "line_status" to
the less confusing "msr".

Also rename the helper function used to parse the interrupt data.

Signed-off-by: Johan Hovold <johan@kernel.org>

USB: serial: ch341: rename shadow modem-control register

Rename the shadow modem-control register currently named "line_control"
to the less confusing "mcr".

Signed-off-by: Johan Hovold <johan@kernel.org>

USB: serial: ch341: clean up control debug messages

Clean up the control-transfer debug messages by dropping redundant
information and unnecessary casts.

Signed-off-by: Johan Hovold <johan@kernel.org>

USB: serial: ch341: fix modem-status handling

The modem-status register was read as part of device configuration at
port_probe and then again at open (and reset-resume). During open (and
reset-resume) the MSR was read before submitting the interrupt URB,
something which could lead to an MSR-change going unnoticed when it
races with open (reset-resume).

Fix this by dropping the redundant reconfiguration of the port at every
open, and only read the MSR after the interrupt URB has been submitted.

Fixes: 664d5df92e88 ("USB: usb-serial ch341: support for DTR/RTS/CTS")
Signed-off-by: Johan Hovold <johan@kernel.org>

USB: serial: ch341: fix control-message error handling

A short control transfer would currently fail to be detected, something
which could lead to stale buffer data being used as valid input.

Check for short transfers, and make sure to log any transfer errors.

Note that this also avoids leaking heap data to user space (TIOCMGET)
and the remote device (break control).

Fixes: 6ce76104781a ("USB: Driver for CH341 USB-serial adaptor")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Johan Hovold <johan@kernel.org>

USB: serial: ch341: fix baud rate and line-control handling

Revert to using direct register writes to set the divisor and
line-control registers.

A recent change switched to using the init vendor command to update
these registers, something which also enabled support for CH341A
devices. It turns out that simply setting bit 7 in the divisor register
is sufficient to support CH341A and specifically prevent data from being
buffered until a full endpoint-size packet (32 bytes) has been received.

Using the init command also had the side-effect of temporarily
deasserting the DTR/RTS signals on every termios change (including
initialisation on open) something which for example could cause problems
in setups where DTR is used to trigger a reset.

Fixes: 4e46c410e050 ("USB: serial: ch341: reinitialize chip on
reconfiguration")
Signed-off-by: Johan Hovold <johan@kernel.org>

USB: serial: ch341: fix line settings after reset-resume

A recent change added support for modifying the default line-control
settings, but did not make sure that the modified settings were used as
part of reconfiguration after a device has been reset during resume.

This caused a port that was open before suspend to be unusable until
being closed and reopened.

Fixes: ba781bdf8662 ("USB: serial: ch341: add support for parity, frame
length, stop bits")
Signed-off-by: Johan Hovold <johan@kernel.org>

USB: serial: ch341: fix resume after reset

Fix reset-resume handling which failed to resubmit the read and
interrupt URBs, thereby leaving a port that was open before suspend in a
broken state until closed and reopened.

Fixes: 1ded7ea47b88 ("USB: ch341 serial: fix port number changed after
resume")
Fixes: 2bfd1c96a9fb ("USB: serial: ch341: remove reset_resume callback")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Johan Hovold <johan@kernel.org>

USB: serial: ch341: fix open error handling

Make sure to stop the interrupt URB before returning on errors during
open.

Fixes: 664d5df92e88 ("USB: usb-serial ch341: support for DTR/RTS/CTS")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Johan Hovold <johan@kernel.org>

USB: serial: ch341: fix modem-control and B0 handling

The modem-control signals are managed by the tty-layer during open and
should not be asserted prematurely when set_termios is called from
driver open.

Also make sure that the signals are asserted only when changing speed
from B0.

Fixes: 664d5df92e88 ("USB: usb-serial ch341: support for DTR/RTS/CTS")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Johan Hovold <johan@kernel.org>

USB: serial: ch341: fix open and resume after B0

The private baud_rate variable is used to configure the port at open and
reset-resume and must never be set to (and left at) zero or reset-resume
and all further open attempts will fail.

Fixes: aa91def41a7b ("USB: ch341: set tty baud speed according to tty
struct")
Fixes: 664d5df92e88 ("USB: usb-serial ch341: support for DTR/RTS/CTS")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Johan Hovold <johan@kernel.org>

USB: serial: ch341: fix initial modem-control state

DTR and RTS will be asserted by the tty-layer when the port is opened
and deasserted on close (if HUPCL is set). Make sure the initial state
is not-asserted before the port is first opened as well.

Fixes: 664d5df92e88 ("USB: usb-serial ch341: support for DTR/RTS/CTS")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Johan Hovold <johan@kernel.org>

USB: serial: ch341: add debug output for chip version

Will probably be helpful if there are any more compatibility issues.

Signed-off-by: Aidan Thornton <makosoft@gmail.com>
Reviewed-by: Grigori Goronzy <greg@chown.ath.cx>
Signed-off-by: Johan Hovold <johan@kernel.org>

USB: serial: ch341: add support for parity, frame length, stop bits

With the new reinitialization method, configuring parity, different
frame lengths and different stop bit settings should work as expected
on both CH340G and CH341A. Tested on a loopback-connected CH340G
with a logic analyzer in a number of different configurations.

Based on a patch by Grigori Goronzy

Signed-off-by: Aidan Thornton <makosoft@gmail.com>
Reviewed-by: Grigori Goronzy <greg@chown.ath.cx>
Signed-off-by: Johan Hovold <johan@kernel.org>

USB: serial: ch341: reinitialize chip on reconfiguration

Changing the LCR register after initialization does not seem to be reliable
on all chips (particularly not on CH341A). Restructure initialization and
configuration to always reinit the chip on configuration changes instead and
pass the LCR register value directly to the initialization command.

(Note that baud rates above 500kbaud are incorrect, but they're incorrect in
the same way both before and after this patch at least on the CH340G. Fixing
this isn't a priority as higher baud rates don't seem that reliable anyway.)

Cleaned-up version of a patch by Grigori Goronzy

Signed-off-by: Aidan Thornton <makosoft@gmail.com>
Reviewed-by: Grigori Goronzy <greg@chown.ath.cx>
Signed-off-by: Johan Hovold <johan@kernel.org>

USB: serial: ch341: add register and USB request definitions

No functional changes, this just gives names to some registers and USB
requests based on Grigori Goronzy's work and WinChipTech's Linux driver
(which reassuringly agree), then uses them in place of magic numbers.
This also renames the misnamed BREAK2 register (actually UART config)

Signed-off-by: Aidan Thornton <makosoft@gmail.com>
Reviewed-by: Grigori Goronzy <greg@chown.ath.cx>
Signed-off-by: Johan Hovold <johan@kernel.org>

USB: serial: fix compare_const_fl.cocci warnings

Move constants to the right of binary operators where it increases
readability.

Generated by: scripts/coccinelle/misc/compare_const_fl.cocci

Signed-off-by: Mathieu OTHACEHE <m.othacehe@gmail.com>
[johan: drop some chunks and fix others, amend commit message ]
Signed-off-by: Johan Hovold <johan@kernel.org>

USB: ch341: set tty baud speed according to tty struct

The ch341_set_baudrate() function initialize the device baud speed
according to the value on priv->baud_rate. By default the ch341_open() set
it to a hardcoded value (DEFAULT_BAUD_RATE 9600). Unfortunately, the
tty_struct is not initialized with the same default value. (usually 56700)

This means that the tty_struct and the device baud rate generator are not
synchronized after opening the port.

Fixup is done by calling ch341_set_termios() if tty exist.
Remove unnecessary variable priv->baud_rate setup as it's already done by
ch341_port_probe().
Remove unnecessary call to ch341_set_{handshake,baudrate}() in
ch341_open() as there already called in ch341_configure() and
ch341_set_termios()

Signed-off-by: Nicolas PLANEL <nicolas.planel@enovance.com>
Signed-off-by: Johan Hovold <johan@kernel.org>

USB: ch341: remove redundant close from open error path

Remove redundant call to ch341_close from error path when submission of
the interrupt urb fails in open.

Signed-off-by: Johan Hovold <johan@kernel.org>

USB: serial: add missing newlines to dev_<level> messages.

Add missing newlines to dev_<level> messages.

Also make some messages less verbose where appropriate.

Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <greg@kroah.com>

usb: delete non-required instances of include <linux/init.h>

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.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

USB: ch341: clean up interrupt handler

Clean up interrupt completion handler somewhat.

Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

USB: ch341: switch to generic TIOCMIWAIT implementation

Switch to the generic TIOCMIWAIT implementation which does not suffer
from the races involved when using the deprecated sleep_on functions.

Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

USB: ch341: only wake up MSR queue on changes

Only wake up MSR wait queue on actual modem-status changes.

Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

USB: ch341: fix ignored TIOCMIWAIT mask

Make sure the TIOCMIWAIT mask is always honoured.

The CH341 interrupt status has a multiple-status changed flag which
indicates that multiple status changes has occurred since last interrupt
event. Unfortunately, if the final status is the same, there appears to
be no way to determine which signal(s) has changed (an even number of
times).

This means that the multiple-status flag should not be used in
TIOCMIWAIT as it leads to the signal mask argument being ignored (e.g.
TIOCMIWAIT could return if DSR changes twice, even though the user only
cares about carrier changes).

Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

USB: ch341: clean up line-status handling

Clean up line-status handling.

Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

USB: ch341: refactor line-status handling

Refactor line-status handling.

Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

USB: serial: remove redundant OOM messages

Remove redundant error messages on allocation failures, which have
already been logged.

Cc: Joe Perches <joe@perches.com>
Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

USB: ch341: fix TIOCMIWAIT and disconnect

Use tty-port modem-status-change wait queue on which processes are woken
up at hangup and disconnect.

Currently a process waiting on modem-status changes will not be woken on
device disconnect as wake up was only done in dtr_rts which isn't
guaranteed to be called (e.g. if HUPCL is not set).

Also remove the redundant wake-up call from dtr_rts.

Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

USB: ch341: replace custom ioctl operation with tiocmiwait

Replace custom ioctl operation with tiocmiwait.

Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

USB: ch341: fix use-after-free in TIOCMIWAIT

Use the port wait queue and make sure to check the serial disconnected
flag before accessing private port data after waking up.

This is is needed as the private port data (including the wait queue
itself) can be gone when waking up after a disconnect.

Cc: stable <stable@vger.kernel.org>
Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

USB: ch341: fix port-data memory leak

Fix port-data memory leak by moving port data allocation to port_probe
and actually implementing deallocation.

Note that this driver has never even bothered to try to deallocate it's
port data...

Compile-only tested.

Cc: <stable@vger.kernel.org>
Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

USB: Serial: ch341.c: remove debug module parameter

Now that all usb-serial modules are only using dev_dbg()
the debug module parameter does not do anything at all, so
remove it to reduce any confusion if someone were to try to
use it.

CC: Johan Hovold <jhovold@gmail.com>
CC: Alan Stern <stern@rowland.harvard.edu>
CC: Rusty Russell <rusty@rustcorp.com.au>
CC: Mauro Carvalho Chehab <mchehab@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

USB: serial: remove debug parameter from usb_serial_debug_data()

We should use dev_dbg() for usb_serial_debug_data() like all of the rest
of the usb-serial drivers use, so remove the debug parameter as it's not
needed.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

USB: serial: ch341.c: remove dbg() usage

dbg() was a very old USB-serial-specific macro.
This patch removes it from being used in the
driver and uses dev_dbg() instead.

CC: Johan Hovold <jhovold@gmail.com>
CC: Alan Stern <stern@rowland.harvard.edu>
CC: Rusty Russell <rusty@rustcorp.com.au>
CC: Mauro Carvalho Chehab <mchehab@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

USB: serial: ch341: make the reset_resume callback actually work.

I hooked up the wrong callback in my previous patch, this should fix it.

Reported-by: Alan Stern <stern@rowland.harvard.edu>
Cc: Johan Hovold <jhovold@gmail.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Mauro Carvalho Chehab <mchehab@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

USB: serial: ch341: put reset_resume callback back.

A few patches ago, I removed the reset_resume callback, changing it to
resume instead. Now that the usb-serial core supports reset_resume, put
this driver callback back as well, so it should work identically to how
it was originally.

Now if this function really is doing what it should be doing, well,
that's a different story, but we are at least doing the identical thing
that we were before...

Cc: Johan Hovold <jhovold@gmail.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Mauro Carvalho Chehab <mchehab@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

USB: serial: rework usb_serial_register/deregister_drivers()

This reworks the usb_serial_register_drivers() and
usb_serial_deregister_drivers() to not need a pointer to a struct
usb_driver anymore. The usb_driver structure is now created dynamically
and registered and unregistered as needed.

This saves lines of code in each usb-serial driver. All in-kernel users
of these functions were also fixed up at this time. The pl2303 driver
was tested that everything worked properly.

Thanks for the idea to do this from Alan Stern.

Cc: Adhir Ramjiawan <adhirramjiawan0@gmail.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Al Borchers <alborchers@steinerpoint.com>
Cc: Aleksey Babahin <tamerlan311@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andrew Worsley <amworsley@gmail.com>
Cc: Bart Hartgers <bart.hartgers@gmail.com>
Cc: Bill Pemberton <wfp5p@virginia.edu>
Cc: Dan Carpenter <error27@gmail.com>
Cc: Dan Williams <dcbw@redhat.com>
Cc: Donald Lee <donald@asix.com.tw>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Felipe Balbi <balbi@ti.com>
Cc: Gary Brubaker <xavyer@ix.netcom.com>
Cc: Jesper Juhl <jj@chaosbits.net>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Johan Hovold <jhovold@gmail.com>
Cc: Julia Lawall <julia@diku.dk>
Cc: Kautuk Consul <consul.kautuk@gmail.com>
Cc: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Cc: Lonnie Mendez <dignome@gmail.com>
Cc: Matthias Bruestle and Harald Welte <support@reiner-sct.com>
Cc: Matthias Urlichs <smurf@smurf.noris.de>
Cc: Mauro Carvalho Chehab <mchehab@redhat.com>
Cc: Michal Sroczynski <msroczyn@gmail.com>
Cc: "Michał Wróbel" <michal.wrobel@flytronic.pl>
Cc: Oliver Neukum <oliver@neukum.name>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Peter Berger <pberger@brimson.com>
Cc: Preston Fick <preston.fick@silabs.com>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: Rigbert Hamisch <rigbert@gmx.de>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Simon Arlott <simon@fire.lp0.eu>
Cc: Support Department <support@connecttech.com>
Cc: Thomas Tuttle <ttuttle@chromium.org>
Cc: Uwe Bonnes <bon@elektron.ikp.physik.tu-darmstadt.de>
Cc: Wang YanQing <Udknight@gmail.com>
Cc: William Greathouse <wgreathouse@smva.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

USB: serial: ch341: remove reset_resume callback

This really just is the resume callback for the device, so use that,
especially as the usb-serial core just overrode this callback so it
wasn't being made anyway.

Cc: Johan Hovold <jhovold@gmail.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Mauro Carvalho Chehab <mchehab@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

USB: serial: remove usb_serial_disconnect call in all drivers

This is now set by the usb-serial core, no need for the driver to
individually set it.

Thanks to Alan Stern for the idea to get rid of it.

Cc: William Greathouse <wgreathouse@smva.com>
Cc: Matthias Bruestle and Harald Welte <support@reiner-sct.com>
Cc: Lonnie Mendez <dignome@gmail.com>
Cc: Peter Berger <pberger@brimson.com>
Cc: Al Borchers <alborchers@steinerpoint.com>
Cc: Gary Brubaker <xavyer@ix.netcom.com>
Cc: Oliver Neukum <oliver@neukum.name>
Cc: Matthias Urlichs <smurf@smurf.noris.de>
Cc: Support Department <support@connecttech.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Mauro Carvalho Chehab <mchehab@redhat.com>
Cc: Kautuk Consul <consul.kautuk@gmail.com>
Cc: Bill Pemberton <wfp5p@virginia.edu>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Bart Hartgers <bart.hartgers@gmail.com>
Cc: Johan Hovold <jhovold@gmail.com>
Cc: Preston Fick <preston.fick@silabs.com>
Cc: Uwe Bonnes <bon@elektron.ikp.physik.tu-darmstadt.de>
Cc: Simon Arlott <simon@fire.lp0.eu>
Cc: Andrew Worsley <amworsley@gmail.com>
Cc: "Michał Wróbel" <michal.wrobel@flytronic.pl>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Felipe Balbi <balbi@ti.com>
Cc: Aleksey Babahin <tamerlan311@gmail.com>
Cc: Dan Carpenter <error27@gmail.com>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Donald Lee <donald@asix.com.tw>
Cc: Julia Lawall <julia@diku.dk>
Cc: Michal Sroczynski <msroczyn@gmail.com>
Cc: Wang YanQing <Udknight@gmail.com>
Cc: Dan Williams <dcbw@redhat.com>
Cc: Thomas Tuttle <ttuttle@chromium.org>
Cc: Rigbert Hamisch <rigbert@gmx.de>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Cc: Jesper Juhl <jj@chaosbits.net>
Cc: Adhir Ramjiawan <adhirramjiawan0@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

USB: serial: remove usb_serial_probe call in all drivers

This is now set by the usb-serial core, no need for the driver to
individually set it.

Thanks to Alan Stern for the idea to get rid of it.

Cc: William Greathouse <wgreathouse@smva.com>
Cc: Matthias Bruestle and Harald Welte <support@reiner-sct.com>
Cc: Lonnie Mendez <dignome@gmail.com>
Cc: Peter Berger <pberger@brimson.com>
Cc: Al Borchers <alborchers@steinerpoint.com>
Cc: Gary Brubaker <xavyer@ix.netcom.com>
Cc: Oliver Neukum <oliver@neukum.name>
Cc: Matthias Urlichs <smurf@smurf.noris.de>
Cc: Support Department <support@connecttech.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Mauro Carvalho Chehab <mchehab@redhat.com>
Cc: Kautuk Consul <consul.kautuk@gmail.com>
Cc: Bill Pemberton <wfp5p@virginia.edu>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Bart Hartgers <bart.hartgers@gmail.com>
Cc: Johan Hovold <jhovold@gmail.com>
Cc: Preston Fick <preston.fick@silabs.com>
Cc: Uwe Bonnes <bon@elektron.ikp.physik.tu-darmstadt.de>
Cc: Simon Arlott <simon@fire.lp0.eu>
Cc: Andrew Worsley <amworsley@gmail.com>
Cc: "Michał Wróbel" <michal.wrobel@flytronic.pl>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Felipe Balbi <balbi@ti.com>
Cc: Aleksey Babahin <tamerlan311@gmail.com>
Cc: Dan Carpenter <error27@gmail.com>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Donald Lee <donald@asix.com.tw>
Cc: Julia Lawall <julia@diku.dk>
Cc: Michal Sroczynski <msroczyn@gmail.com>
Cc: Wang YanQing <Udknight@gmail.com>
Cc: Dan Williams <dcbw@redhat.com>
Cc: Thomas Tuttle <ttuttle@chromium.org>
Cc: Rigbert Hamisch <rigbert@gmx.de>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Cc: Jesper Juhl <jj@chaosbits.net>
Cc: Adhir Ramjiawan <adhirramjiawan0@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb-serial: clean up unneeded PM-related fields

This patch (as1551) cleans up the PM-related entries in the usb_driver
structures of the various USB serial driver modules. Those entries
are now filled in by the usb-serial core during driver registration,
so they don't need to be initialized explicitly in the source code.

The same is true of the one remaining no_dynamic_id entry.

reset_resume remains a small problem, because the serial core doesn't
support it. The patch ignores these entries.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

USB: ch341.c: remove dbg() tracing calls

dbg() was used a lot a long time ago to trace code flow. Now that we have
ftrace, this isn't needed at all, so remove these calls.

CC: Johan Hovold <jhovold@gmail.com>
CC: Rusty Russell <rusty@rustcorp.com.au>
CC: Alan Stern <stern@rowland.harvard.edu>
CC: Mauro Carvalho Chehab <mchehab@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

USB: serial: ch341.c: use module_usb_serial_driver

This converts the ch341.c driver to use the module_usb_serial_driver() call
instead of having to have a module_init/module_exit function, saving a lot
of duplicated code.

CC: Johan Hovold <jhovold@gmail.com>
CC: Rusty Russell <rusty@rustcorp.com.au>
CC: Alan Stern <stern@rowland.harvard.edu>
CC: Mauro Carvalho Chehab <mchehab@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb-serial: use new registration API in [a-c]* drivers

This patch (as1523) modifies the following usb-serial drivers to
utilize the new usb_serial_{de}register_drivers() routines:

aircable, ark3116, belkin_sa, ch341, cp210x, cyberjack,
and cypress_m8.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

module_param: make bool parameters really bool (drivers & misc)

module_param(bool) used to counter-intuitively take an int. In
fddd5201 (mid-2009) we allowed bool or int/unsigned int using a messy
trick.

It's time to remove the int/unsigned int option. For this version
it'll simply give a warning, but it'll break next kernel version.

Acked-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

USB: ch341: forward USB errors to USB serial core

All error messages from stack in open are being forwarded except for
one call to usb_submit_urb. Change this for consistency.

Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

USB: serial: remove unnecessary reinitialisations of urb->dev

Remove unnecessary reinitialisations of urb->dev before each submission,
which were based on the (no longer valid) assumption that serial->dev
will be set to NULL on close.

Compile-only tested.

Cc: Matthias Bruestle and Harald Welte <support@reiner-sct.com>
Cc: Lonnie Mendez <dignome@gmail.com>
Cc: Peter Berger <pberger@brimson.com>
Cc: Al Borchers <alborchers@steinerpoint.com>
Cc: Support Department <support@connecttech.com>
Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

USB: serial: ch341: add new id

I picked up a new DAK-780EX(professional digitl reverb/mix system),
which use CH341T chipset to communication with computer on 3/2011
and the CH341T's vendor code is 1a86

Looking up the CH341T's vendor and product id's I see:

1a86 QinHeng Electronics
5523 CH341 in serial mode, usb to serial port converter

CH341T,CH341 are the products of the same company, maybe
have some common hardware, and I test the ch341.c works
well with CH341T

Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: stable <stable@kernel.org>

Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

tty: remove filp from the USB tty ioctls

We don't use it so we can trim it from here as we try and stamp the file
object dependencies out of the serial code.

Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

tiocmset: kill the file pointer argument

Doing tiocmget was such fun we should do tiocmset as well for the same
reasons

Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

tiocmget: kill off the passing of the struct file

We don't actually need this and it causes problems for internal use of
this functionality. Currently there is a single use of the FILE * pointer.
That is the serial core which uses it to check tty_hung_up_p. However if
that is true then IO_ERROR is also already set so the check may be removed.

Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

USB: serial: handle Data Carrier Detect changes

Alan's commit 335f8514f200e63d689113d29cb7253a5c282967 introduced
.carrier_raised function in several drivers. That also means
tty_port_block_til_ready can now suspend the process trying to open the serial
port when Carrier Detect is low and put it into tty_port.open_wait queue. We
need to wake up the process when Carrier Detect goes high and trigger TTY
hangup when CD goes low.

Some of the devices do not report modem status line changes, or at least we
don't understand the status message, so for those we remove .carrier_raised
again.

Signed-off-by: Libor Pechacek <lpechacek@suse.cz>
Cc: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

USB: serial: refactor generic close

Export usb_serial_generic_close so that drivers can easily kill the read
and write urb and make sure that the write fifo is reset.

Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h

percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files. percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.

percpu.h -> slab.h dependency is about to be removed. Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability. As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.

http://userweb.kernel.org/~tj/misc/slabh-sweep.py

The script does the followings.

* Scan files for gfp and slab usages and update includes such that
only the necessary includes are there. ie. if only gfp is used,
gfp.h, if slab is used, slab.h.

* When the script inserts a new include, it looks at the include
blocks and try to put the new include such that its order conforms
to its surrounding. It's put in the include block which contains
core kernel includes, in the same order that the rest are ordered -
alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
doesn't seem to be any matching order.

* If the script can't find a place to put a new include (mostly
because the file doesn't have fitting include block), it prints out
an error message indicating which .h file needs to be added to the
file.

The conversion was done in the following steps.

1. The initial automatic conversion of all .c files updated slightly
over 4000 files, deleting around 700 includes and adding ~480 gfp.h
and ~3000 slab.h inclusions. The script emitted errors for ~400
files.

2. Each error was manually checked. Some didn't need the inclusion,
some needed manual addition while adding it to implementation .h or
embedding .c file was more appropriate for others. This step added
inclusions to around 150 files.

3. The script was run again and the output was compared to the edits
from #2 to make sure no file was left behind.

4. Several build tests were done and a couple of problems were fixed.
e.g. lib/decompress_*.c used malloc/free() wrappers around slab
APIs requiring slab.h to be added manually.

5. The script was run on all .h files but without automatically
editing them as sprinkling gfp.h and slab.h inclusions around .h
files could easily lead to inclusion dependency hell. Most gfp.h
inclusion directives were ignored as stuff from gfp.h was usually
wildly available and often used in preprocessor macros. Each
slab.h inclusion directive was examined and added manually as
necessary.

6. percpu.h was updated not to include slab.h.

7. Build test were done on the following configurations and failures
were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my
distributed build env didn't work with gcov compiles) and a few
more options had to be turned off depending on archs to make things
build (like ipr on powerpc/64 which failed due to missing writeq).

* x86 and x86_64 UP and SMP allmodconfig and a custom test config.
* powerpc and powerpc64 SMP allmodconfig
* sparc and sparc64 SMP allmodconfig
* ia64 SMP allmodconfig
* s390 SMP allmodconfig
* alpha SMP allmodconfig
* um on x86_64 SMP allmodconfig

8. percpu.h modifications were reverted so that it could be applied as
a separate patch and serve as bisection point.

Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.

Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>

USB serial: make USB device id constant

The id_table field of the struct usb_device_id is constant in <linux/usb.h>
so it is worth to make the initialization data also constant.

The semantic match that finds this kind of pattern is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@r@
disable decl_init,const_decl_init;
identifier I1, I2, x;
@@
struct I1 {
...
const struct I2 *x;
...
};
@s@
identifier r.I1, y;
identifier r.x, E;
@@
struct I1 y = {
.x = E,
};
@c@
identifier r.I2;
identifier s.E;
@@
const struct I2 E[] = ... ;
@depends on !c@
identifier r.I2;
identifier s.E;
@@
+ const
struct I2 E[] = ...;
// </smpl>

Signed-off-by: Németh Márton <nm127@freemail.hu>
Cc: Julia Lawall <julia@diku.dk>
Cc: cocci@diku.dk
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

USB: ch341: use get_unaligned_le16 in break_ctl

Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

USB: ch341: use le16_to_cpup to be explicit about endianess

Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

USB: ch341: fix DMA buffer on stack

Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

USB: ch341: replace printk warnings with dev_err

Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

USb: Break support for WinChipHead CH341 340 USB->Serial "chip"

Here is a patch to the ch341 driver which adds serial break support.

Signed-off-by: Tim Small <tim@seoss.co.uk>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

tty: USB does not need the filp argument in the drivers

And indeed none of them use it. Clean this up as it will make moving to a
standard open method rather easier.

Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

tty: Bring the usb tty port structure into more use

This allows us to clean stuff up, but is probably also going to cause
some app breakage with buggy apps as we now implement proper POSIX behaviour
for USB ports matching all the other ports. This does also mean other apps
that break on USB will now work properly.

Signed-off-by: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

USB: usb-serial ch341: support for DTR/RTS/CTS

commit 664d5df92e88b6ef091048a802b3750f4e989180 upstream.

Fixup of Werner Cornelius patch to the ch341 USB-serial driver, which adds:
- support all baudrates, not just a hard-coded set
- support for controlling DTR, RTS and CTS

Features still missing:
- character length other than 8 bits
- parity settings
- break control

I adapted his patch for the new usb_serial API introduced in 2.6.25-git8 by
Alan Cox on 22 July 2008. Non-compliance to the new API was a reason for
refusing a similar patch from Tollef Fog Heen.

Usage example by Tollef Fog Heen :
TEMPer USB thermometer <http://err.no/src/TEMPer.c>

based on a patch by:

From: Tollef Fog Heen <tfheen@err.no>

* Implement support for all baud rates rather than just a hard
coded set.
* Make it possible to control status and control lines
* Grab a bunch of #defines from FreeBSD to reduce the number of
magic numbers in the file

Signed-off-by: Werner Cornelius <Werner.Cornelius@cornelius-consult.de>
Signed-off-by: Boris Hajduk <boris@hajduk.org>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Tollef Fog Heen <tfheen@err.no>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

Revert USB: usb-serial ch341: support for DTR/RTS/CTS

Reverts commit 664d5df92e88b6ef091048a802b3750f4e989180 as the commit
log information was not complete, and we didn't have a proper
signed-off-by by the author of the original BSD code.

Cc: Werner Cornelius <Werner.Cornelius@cornelius-consult.de>
Cc: Boris Hajduk <boris@hajduk.org>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

USB: ch341 serial: fix port number changed after resume

This patch fixes the following bug:
.plug ch341 usb serial port into a hub port;
.ch341 driver bound to the device and /dev/ttyUSB0 comes
.open /dev/ttyUSB0 by minicom and we can use the serial successfully
.suspend the ch341 usb serial device(such as: echo suspend > power/level)
.resume the ch341 usb serial device (such as: echo on > power/level)
.new port /dev/ttyUSB1 comes ,and the original /dev/ttyUSB0 still exists,
but is no longer usable by minicom

The patch adds suspend and resume callback to ch341 usb driver to prevent it
from unbinding during suspend. The /dev/ttyUSB0 is not released until being
closed, so /dev/ttyUSB1 comes after resume, and the original /dev/ttyUSB0 is
no longer usable by minicom. It is really a mess for a minicom user.

This patch also adds the reset_resume callback to make it usable after resuming
from STR or hibernation, for generally STR or hibernation will make the vbus
of root-hub lost.

Finally enable the driver's supports_autosuspend, for the device is in working
order with it.

Signed-off-by: Ming Lei <tom.leiming@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

USB: usb-serial ch341: support for DTR/RTS/CTS

Fixup of Werner Cornelius patch to the ch341 USB-serial driver, which adds:
- support all baudrates, not just a hard-coded set
- support for controlling DTR, RTS and CTS

Features still missing:
- character length other than 8 bits
- parity settings
- break control

I adapted his patch for the new usb_serial API introduced in 2.6.25-git8 by
Alan Cox on 22 July 2008. Non-compliance to the new API was a reason for
refusing a similar patch from Tollef Fog Heen.

Usage example by Tollef Fog Heen :
TEMPer USB thermometer <http://err.no/src/TEMPer.c>

Signed-off-by: Werner Cornelius <Werner.Cornelius@cornelius-consult.de>
Signed-off-by: Boris Hajduk <boris@hajduk.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

usb_serial: API all change

USB serial likes to use port->tty back pointers for the real work it does and
to do so without any actual locking. Unfortunately when you consider hangup
events, hangup/parallel reopen or even worse hangup followed by parallel close
events the tty->port and port->tty pointers are not guaranteed to be the same
as port->tty is the active tty while tty->port is the port the tty may or
may not still be attached to.

So rework the entire API to pass the tty struct. For console cases we need
to pass both for now. This shows up multiple drivers that immediately crash
with USB console some of which have been fixed in the process.

Longer term we need a proper tty as console abstraction

Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

USB: serial: ch341: New VID/PID for CH341 USB-serial

Recent USB-serial devices using the WinChipHead CH340/CH341 chipset are
being shipped with a new vendor/product ID code pair, but an otherwise
identical device. (This is confirmed by looking at INF for the included
Windows driver.)

Patch is tested and working, both with new and old devices.

Signed-off-by: Michael F. Robbins <mrobbins@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

usb_serial: some coding style fixes

Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

USB: serial: remove unneeded number endpoints settings

The usb-serial core no longer checks these fields so remove them from
all of the individual drivers. They will be removed from the usb-serial
core in a patch later in the series.

Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

USB: ch341: fix termios handling

The ch341 currently doesn't support most of the hardware setting. So to keep
the termios data right we propogate the old termios hardware values back then
encode the speed.

Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

USB: usb/serial/ch341.c: make 4 functions static

This patch makes four needlessly global functions static.

Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

USB: Driver for CH341 USB-serial adaptor

This patch implements a USB serial port driver for the Winchiphead
CH341 USB-RS232 Converter. This chip also implements an IEEE 1284
parallel port, I2C and SPI, but that is not supported by the driver.

Signed-off-by: Frank A Kingswood <frank@kingswood-consulting.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>