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>
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: 4e46c410e0 ("USB: serial: ch341: reinitialize chip on reconfiguration")
Cc: stable@vger.kernel.org # 4.10
Signed-off-by: Johan Hovold <johan@kernel.org>
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: 4e46c410e0 ("USB: serial: ch341: reinitialize chip on reconfiguration")
Fixes: 55fa15b598 ("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>
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>
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_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>
This reverts commit 3c18e9baee.
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: 3c18e9baee ("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>
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>
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>
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>
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>
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>
Here are the USB-serial updates for 5.9-rc1, including:
- console flow-control support
- simulated line-breaks on some ch341
- hardware flow-control fixes for cp210x
- break-detection and sysrq fixes for ftdi_sio
- sysrq optimisations
- input parity checking for cp210x
Included are also some new device ids and various clean ups.
All have been in linux-next with no reported issues.
-----BEGIN PGP SIGNATURE-----
iHUEABYIAB0WIQQHbPq+cpGvN/peuzMLxc3C7H1lCAUCXyAjIwAKCRALxc3C7H1l
CHruAQDTSejnRcrxMqU6mqL2AuEw+fABGUxjE+ah/HbXMf7CDwD/d0XQFimA8U8J
ovxTVm35R+vYQ7T7jTNuVxso6nWGxw8=
=15J7
-----END PGP SIGNATURE-----
Merge tag 'usb-serial-5.9-rc1' of https://git.kernel.org/pub/scm/linux/kernel/git/johan/usb-serial into usb-next
Johan writes:
USB-serial updates for 5.9-rc1
Here are the USB-serial updates for 5.9-rc1, including:
- console flow-control support
- simulated line-breaks on some ch341
- hardware flow-control fixes for cp210x
- break-detection and sysrq fixes for ftdi_sio
- sysrq optimisations
- input parity checking for cp210x
Included are also some new device ids and various clean ups.
All have been in linux-next with no reported issues.
* tag 'usb-serial-5.9-rc1' of https://git.kernel.org/pub/scm/linux/kernel/git/johan/usb-serial: (31 commits)
USB: serial: qcserial: add EM7305 QDL product ID
USB: serial: iuu_phoenix: fix led-activity helpers
USB: serial: sierra: clean up special-interface handling
USB: serial: cp210x: use in-kernel types in port data
USB: serial: cp210x: drop unnecessary packed attributes
USB: serial: cp210x: add support for TIOCGICOUNT
USB: serial: cp210x: add support for line-status events
USB: serial: cp210x: disable interface on errors in open
USB: serial: drop redundant transfer-buffer casts
USB: serial: drop extern keyword from function declarations
USB: serial: drop unnecessary sysrq include
USB: serial: add sysrq break-handler dummy
USB: serial: inline sysrq dummy function
USB: serial: only process sysrq when enabled
USB: serial: only set sysrq timestamp for consoles
USB: serial: ftdi_sio: fix break and sysrq handling
USB: serial: ftdi_sio: clean up receive processing
USB: serial: ftdi_sio: make process-packet buffer unsigned
USB: serial: use fallthrough pseudo-keyword
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>
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>
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>
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>
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>
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: 3571456508 ("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>
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>
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: 3571456508 ("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>
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: 1ded7ea47b ("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>
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>
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: 2d5a9c72d0 ("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>
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>
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>
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>
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>
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>
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>
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: 664d5df92e ("USB: usb-serial ch341: support for DTR/RTS/CTS")
Signed-off-by: Johan Hovold <johan@kernel.org>
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: 6ce7610478 ("USB: Driver for CH341 USB-serial adaptor")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
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: 4e46c410e0 ("USB: serial: ch341: reinitialize chip on
reconfiguration")
Signed-off-by: Johan Hovold <johan@kernel.org>
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: ba781bdf86 ("USB: serial: ch341: add support for parity, frame
length, stop bits")
Signed-off-by: Johan Hovold <johan@kernel.org>
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: 1ded7ea47b ("USB: ch341 serial: fix port number changed after
resume")
Fixes: 2bfd1c96a9 ("USB: serial: ch341: remove reset_resume callback")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
Make sure to stop the interrupt URB before returning on errors during
open.
Fixes: 664d5df92e ("USB: usb-serial ch341: support for DTR/RTS/CTS")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
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: 664d5df92e ("USB: usb-serial ch341: support for DTR/RTS/CTS")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
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: aa91def41a ("USB: ch341: set tty baud speed according to tty
struct")
Fixes: 664d5df92e ("USB: usb-serial ch341: support for DTR/RTS/CTS")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
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: 664d5df92e ("USB: usb-serial ch341: support for DTR/RTS/CTS")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
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>
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>
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>
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>
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>
Fix up the f81232 driver, which up to this point has mostly been a
placeholder without a proper implementation.
Included is also a minor clean up of ch341.
Signed-off-by: Johan Hovold <johan@kernel.org>
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Merge tag 'usb-serial-4.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/johan/usb-serial into usb-next
Johan writes:
USB-serial updates for v4.1-rc1
Fix up the f81232 driver, which up to this point has mostly been a
placeholder without a proper implementation.
Included is also a minor clean up of ch341.
Signed-off-by: Johan Hovold <johan@kernel.org>
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>
