commit dcf097e7 upstream.

At least some PL2303GL have a bcdDevice of 0x405 instead of 0x100 as the
datasheet claims. Add it to the list of known release numbers for the
HXN (G) type.

Fixes: 894758d0

 ("USB: serial: pl2303: tighten type HXN (G) detection")
Signed-off-by: Robert Marko <robert.marko@sartura.hr>
Cc: stable@vger.kernel.org	# 5.13
Link: https://lore.kernel.org/r/20210826110239.5269-1-robert.marko@sartura.hr

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

At least some PL2303GT have a bcdDevice of 0x305 instead of 0x100 as the
datasheet claims. Add it to the list of known release numbers for the
HXN (G) type.

Fixes: 894758d0

 ("USB: serial: pl2303: tighten type HXN (G) detection")
Reported-by: Vasily Khoruzhick <anarsoul@gmail.com>
Tested-by: Vasily Khoruzhick <anarsoul@gmail.com>
Cc: stable@vger.kernel.org	# 5.13
Link: https://lore.kernel.org/r/20210804093100.24811-1-johan@kernel.org

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

The device release number for HX-type devices is configurable in
EEPROM/OTPROM and cannot be used reliably for type detection.

Assume all (non-H) devices with bcdUSB 1.1 and unknown bcdDevice to be
of HX type while adding a bcdDevice check for HXD and TB (1.1 and 2.0,
respectively).
Reported-by: Chris <chris@cyber-anlage.de>
Fixes: 8a7bf751 ("USB: serial: pl2303: amend and tighten type detection")
Cc: stable@vger.kernel.org	# 5.13
Link: https://lore.kernel.org/r/20210730122156.718-1-johan@kernel.org

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

In the previous patch, we introduced tty_get_char_size() and
tty_get_frame_size() for computing character and frame sizes,
respectively. Here, we make use of them in various tty drivers where
applicable.

The stats look nice: 12 insertions, 169 deletions.

Cc: Arnd Bergmann <arnd@arndb.de>
Cc: David Lin <dtwlin@gmail.com>
Cc: Johan Hovold <johan@kernel.org>
Cc: Alex Elder <elder@kernel.org>
Cc: Shawn Guo <shawnguo@kernel.org>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: Andy Gross <agross@kernel.org>
Cc: Bjorn Andersson <bjorn.andersson@linaro.org>
Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com>
Cc: Alexandre Torgue <alexandre.torgue@foss.st.com>
Cc: Oliver Neukum <oneukum@suse.com>
Acked-by: Alex Elder <elder@kernel.org>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20210610090247.2593-4-jslaby@suse.cz

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

This adds the device id for the ADLINK ND-6530 which is a PL2303GC based
device.
Signed-off-by: Zolton Jheng <s6668c2t@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: Johan Hovold <johan@kernel.org>

The TIOCGSERIAL ioctl can be used to set and retrieve the UART type for
legacy UARTs, but some USB serial drivers have been reporting back
random types in order to "make user-space happy".

Some applications have historically expected TIOCGSERIAL to be
implemented, but judging from the Debian sources, the port type not
being PORT_UNKNOWN is only used to check for the existence of legacy
serial ports (ttySn).

Drivers like ftdi_sio have been using PORT_UNKNOWN for twenty years (and
option for 10 years) without anyone complaining so let's stop reporting
back anything else.

In the unlikely event that this do cause problems, this should be fixed
tree-wide anyway (e.g. for all USB serial drivers and also CDC-ACM).
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Johan Hovold <johan@kernel.org>

TIOCSSERIAL is a horrid, underspecified, legacy interface which for most
serial devices is only useful for setting the close_delay and
closing_wait parameters.

The closing_wait parameter determines how long to wait for the transfer
buffers to drain during close and the default timeout of 30 seconds may
not be sufficient at low line speeds. In other cases, when for example
flow is stopped, the default timeout may instead be too long.

Add generic support for TIOCSSERIAL and TIOCGSERIAL with handling of the
three common parameters close_delay, closing_wait and line for the
benefit of all USB serial drivers while still allowing drivers to
implement further functionality through the existing callbacks.

This currently includes a few drivers that report their base baud clock
rate even if that is really only of interest when setting custom
divisors through the deprecated ASYNC_SPD_CUST interface; an interface
which only the FTDI driver actually implements.

Some drivers have also been reporting back a fake UART type, something
which should no longer be needed and will be dropped by a follow-on
patch.
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Johan Hovold <johan@kernel.org>

TIOCSSERIAL is a horrid, underspecified, legacy interface which for most
serial devices is only useful for setting the close_delay and
closing_wait parameters.

The port parameter is used to set the I/O port and does not make any
sense to use for USB serial devices.

The baud_base parameter could be used to set the UART base clock when it
could not be detected but might as well be left unset when it is not
known.

The close_delay and closing_wait parameters returned by TIOCGSERIAL are
specified in centiseconds. The driver does not yet support changing
these, but let's report back the default values actually used (0.5 and
30 seconds, respectively).
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Johan Hovold <johan@kernel.org>

Use an alternate clock divider algorithm and bit ordering for the TA and
TB versions of the pl2303. It was discovered that these variants do not
produce the correct baud rates with the existing scheme.

see https://lore.kernel.org/r/3aee5708-7961-f464-8c5f-6685d96920d6@IEEE.org

Signed-off-by: Michael G. Katzmann <michaelk@IEEE.org>
Signed-off-by: Johan Hovold <johan@kernel.org>

Add names for the device types to be printed at probe when debugging is
enabled.

Note that the HXN type is referred to as G for now as that is the name
the vendor uses.
Signed-off-by: Johan Hovold <johan@kernel.org>

Tighten the detection of the new HXN (G) type instead of assuming that
every device which doesn't support the old read request is an HXN.
Signed-off-by: Johan Hovold <johan@kernel.org>

Rename the legacy type which is supposedly a PL2303H which came in two
variants (and which we handle the same way).
Signed-off-by: Johan Hovold <johan@kernel.org>

Add support for detecting the HX, TA, TB and HXD device types and refuse
to bind to any unknown types.

Note that the HX type includes the XA variant, while the HXD type
includes the EA, RA and SA variants.
Signed-off-by: Johan Hovold <johan@kernel.org>

Clean up the type detection somewhat in preparation for adding support
for more types.

Note this also fixes the type debug printk for the new HXN type.
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>

The latest chip family (HXN) apparently does not support setting the
line speed using divisors and instead needs to use the direct encoding
scheme for all rates.

This specifically enables 50, 110, 134, 200 bps and other rates not
supported by the original chip type.

Fixes: ebd09f1c

 ("USB: serial: pl2303: add support for PL2303HXN")
Cc: stable@vger.kernel.org      # 5.5
Cc: Charles Yeh <charlesyeh522@gmail.com>
Signed-off-by: Johan Hovold <johan@kernel.org>

This is adds a device id for HP LD381 which is a pl2303GC-base device.
Signed-off-by: Scott Chen <scott@labau.com.tw>
Cc: stable@vger.kernel.org
Signed-off-by: Johan Hovold <johan@kernel.org>

Only set the sysrq timestamp for console ports to avoid having every
driver also check the console flag when processing incoming data.
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Johan Hovold <johan@kernel.org>

Add a device id for HP LD381 Display
LD381:   03f0:0f7f
Signed-off-by: Scott Chen <scott@labau.com.tw>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Johan Hovold <johan@kernel.org>

Prolific has developed a new USB to UART chip: PL2303HXN
PL2303HXN : PL2303GC/PL2303GS/PL2303GT/PL2303GL/PL2303GE/PL2303GB
The Vendor request used by the PL2303HXN (TYPE_HXN) is different from
the existing PL2303 series (TYPE_HX & TYPE_01).
Therefore, different Vendor requests are used to issue related commands.

1. Added a new TYPE_HXN type in pl2303_type_data, and then executes
   new Vendor request,new flow control and other related instructions
   if TYPE_HXN is recognized.

2. Because the new PL2303HXN only accept the new Vendor request,
   the old Vendor request cannot be accepted (the error message
   will be returned)
   So first determine the TYPE_HX or TYPE_HXN through
   PL2303_READ_TYPE_HX_STATUS in pl2303_startup.

  2.1 If the return message is "1", then the PL2303 is the existing
      TYPE_HX/ TYPE_01 series.
      The other settings in pl2303_startup are to continue execution.
  2.2 If the return message is "not 1", then the PL2303 is the new
      TYPE_HXN series.
      The other settings in pl2303_startup are ignored.
      (PL2303HXN will directly use the default value in the hardware,
       no need to add additional settings through the software)

3. In pl2303_open: Because TYPE_HXN is different from the instruction of reset
   down/up stream used by TYPE_HX.
   Therefore, we will also execute different instructions here.

4. In pl2303_set_termios: The UART flow control instructions used by
   TYPE_HXN/TYPE_HX/TYPE_01 are different.
   Therefore, we will also execute different instructions here.

5. In pl2303_vendor_read & pl2303_vendor_write, since TYPE_HXN is different
   from the vendor request instruction used by TYPE_HX/TYPE_01,
   it will also execute different instructions here.

6. In pl2303_update_reg: TYPE_HXN used different register for flow control.
   Therefore, we will also execute different instructions here.
Signed-off-by: Charles Yeh <charlesyeh522@gmail.com>
Signed-off-by: Johan Hovold <johan@kernel.org>

While there are a mix of things here, most of the stuff
were written from Kernel developer's PoV. So, add them to
the driver-api book.

A follow up for this patch would be to move documents from
there that are specific to sysadmins, adding them to the
admin-guide.
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Acked-by: Johan Hovold <johan@kernel.org>
Acked-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

This is adds the vendor and device id for the AT-VT-Kit3 which is a
pl2303-based device.
Signed-off-by: Chris Packham <chris.packham@alliedtelesis.co.nz>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Johan Hovold <johan@kernel.org>

Add helper function to update register bits instead of overwriting the
entire control register when updating the flow-control settings.

This specifically avoids having the tranceiver suspend mode (bit 0)
depend on the flow control setting.

The tranceiver is currently configured at probe to be disabled during
suspend, but this was overridden when disabling flow control or enabling
xon/xoff.

Fixes: 715f9527 ("USB: flow control fix for pl2303")
Fixes: 7041d9c3

 ("USB: serial: pl2303: add support for tx xon/xoff flow control")
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Johan Hovold <johan@kernel.org>

Older pl2303 devices do not support automatic xon/xoff flow control, so
add add a flag to prevent trying to enable it for legacy device types.

Refactor the IXON test into a helper function to improve readability.

Fixes: 7041d9c3

 ("USB: serial: pl2303: add support for tx xon/xoff flow control")
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Johan Hovold <johan@kernel.org>

Add new PID to support PL2303TB (TYPE_HX)
Signed-off-by: Charles Yeh <charlesyeh522@gmail.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Johan Hovold <johan@kernel.org>

Add device ids to pl2303 for the HP POS pole displays:
LM920:   03f0:026b
TD620:   03f0:0956
LD960TA: 03f0:4439
LD220TA: 03f0:4349
LM940:   03f0:5039
Signed-off-by: Scott Chen <scott@labau.com.tw>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Johan Hovold <johan@kernel.org>

Reviewed-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Signed-off-by: Movie Song <MovieSong@aten-itlab.cn>
Cc: Johan Hovold <johan@kernel.org>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Support hardware-level Xon/Xoff flow control in transmit direction with
pl2303.

I only know how to get the hardware to do IXON/!IXANY with ^S/^Q as control
characters, so I preserve the old behaviour for all other cases.
Signed-off-by: Florian Zumbiehl <florz@florz.de>
[ johan: rewrite logic using pl2303_termios_change() helper ]
Signed-off-by: Johan Hovold <johan@kernel.org>

This adds a new device id for Chilitag devices to the pl2303 driver.
Reported-by: "Chu.Mike [朱堅宜]" <Mike-Chu@prolific.com.tw>
Cc: stable <stable@vger.kernel.org>
Acked-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.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>

This adds a new ATEN device id for a new pl2303-based device.
Reported-by: Peter Kuo <PeterKuo@aten.com.tw>
Cc: stable <stable@vger.kernel.org>
Cc: Johan Hovold <johan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Implement the "horrible endpoint hack" for some legacy devices as a
quirk and clean up the code somewhat.

Note that the bulk-endpoint check can be removed as core will already
have verified this.
Signed-off-by: Johan Hovold <johan@kernel.org>

Some pl2303 devices require the use of the interrupt endpoint of an
unrelated interface. This has so far been dealt with in usb-serial core,
but can now be moved to a driver calc_num_ports callback.

Note that we relax the endpoint requirements checked by core and instead
verify that we have an interrupt-in endpoint in calc_num_ports for all
devices so that the hack can first be applied.
Signed-off-by: Johan Hovold <johan@kernel.org>

Simplify the endpoint sanity check by letting core verify that the
required endpoints are present.
Signed-off-by: Johan Hovold <johan@kernel.org>

Seems that ATEN serial-to-usb devices using pl2303 exist with
different device ids. This patch adds a missing device ID so it
is recognised by the driver.
Signed-off-by: Marcel J.E. Mol <marcel@mesa.nl>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Johan Hovold <johan@kernel.org>

Make sure to return an error on zero-length transfers when retrieving
the line settings even if the driver currently ignores the return value.

Also remove a redundant check for short transfer when setting the line
settings.
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Johan Hovold <johan@kernel.org>

Fix NULL-pointer dereference in open() should a type-0 or type-1 device
lack the expected endpoints:

Unable to handle kernel NULL pointer dereference at virtual address 00000030
...
PC is at pl2303_open+0x38/0xec [pl2303]

Note that a missing interrupt-in endpoint would have caused open() to
fail.

Fixes: 1da177e4

 ("Linux-2.6.12-rc2")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Johan Hovold <johan@kernel.org>