kernel.git/drivers/tty/moxa.c, branch linux-5.14.y

tty: make tty_operations::chars_in_buffer return uint

2021-05-13T16:29:11Z

tty_operations::chars_in_buffer is another hook which is expected to return values >= 0. So make it explicit by the return type too -- use unsigned int. Signed-off-by: Jiri Slaby Acked-By: Anton Ivanov Acked-by: David Sterba Cc: Jeff Dike Cc: Richard Weinberger Cc: Arnd Bergmann Cc: Samuel Iglesias Gonsalvez Cc: Jens Taprogge Cc: Karsten Keil Cc: Ulf Hansson Cc: "David S. Miller" Cc: Jakub Kicinski Cc: Heiko Carstens Cc: Vasily Gorbik Cc: Christian Borntraeger Cc: David Lin Cc: Johan Hovold Cc: Alex Elder Cc: Jiri Kosina Cc: Shawn Guo Cc: Sascha Hauer Cc: Oliver Neukum Cc: Felipe Balbi Cc: Mathias Nyman Cc: Marcel Holtmann Cc: Johan Hedberg Cc: Luiz Augusto von Dentz Link: https://lore.kernel.org/r/20210505091928.22010-27-jslaby@suse.cz Signed-off-by: Greg Kroah-Hartman

tty: make tty_operations::write_room return uint

2021-05-13T15:03:20Z

Line disciplines expect a positive value or zero returned from tty->ops->write_room (invoked by tty_write_room). So make this assumption explicit by using unsigned int as a return value. Both of tty->ops->write_room and tty_write_room. Signed-off-by: Jiri Slaby Acked-by: Laurentiu Tudor Acked-by: Alex Elder Acked-by: Max Filippov # xtensa Acked-by: David Sterba Acked-By: Anton Ivanov Acked-by: Geert Uytterhoeven Cc: Richard Henderson Cc: Ivan Kokshaysky Cc: Matt Turner Cc: "James E.J. Bottomley" Cc: Helge Deller Cc: Jeff Dike Cc: Richard Weinberger Cc: Chris Zankel Cc: Arnd Bergmann Cc: Samuel Iglesias Gonsalvez Cc: Jens Taprogge Cc: Karsten Keil Cc: Scott Branden Cc: Ulf Hansson Cc: "David S. Miller" Cc: Jakub Kicinski Cc: Heiko Carstens Cc: Vasily Gorbik Cc: Christian Borntraeger Cc: David Lin Cc: Johan Hovold Cc: Jiri Kosina Cc: Shawn Guo Cc: Sascha Hauer Cc: Oliver Neukum Cc: Felipe Balbi Cc: Mathias Nyman Cc: Marcel Holtmann Cc: Johan Hedberg Cc: Luiz Augusto von Dentz Link: https://lore.kernel.org/r/20210505091928.22010-23-jslaby@suse.cz Signed-off-by: Greg Kroah-Hartman

tty: cumulate and document tty_struct::flow* members

2021-05-13T14:57:16Z

Group the flow flags under a single struct called flow. The new struct contains 'stopped' and 'tco_stopped' bools which used to be bits in a bitfield. The struct also contains the lock protecting them to potentially share the same cache line. Note that commit c545b66c6922b (tty: Serialize tcflow() with other tty flow control changes) added a padding to the original bitfield. It was for the bitfield to occupy a whole 64b word to avoid interferring stores on Alpha (cannot we evaporate this arch with weird implications to C code yet?). But it doesn't work as expected as the padding (tty_struct::unused) is aligned to a 8B boundary too and occupies some bytes from the next word. So make it reliable by: 1) setting __aligned of the struct -- that aligns the start, and 2) making 'unsigned long unused[0]' as the last member of the struct -- pads the end. This is also the perfect time to start the documentation of tty_struct where all this lives. So we start by documenting what these bools actually serve for. And why we do all the alignment dances. Only the few up-to-date information from the Theodore's comment made it into this new Kerneldoc comment. Signed-off-by: Jiri Slaby Cc: "David S. Miller" Cc: Jakub Kicinski Cc: Jonathan Corbet Cc: Arnd Bergmann Cc: Ulf Hansson Cc: Heiko Carstens Cc: Vasily Gorbik Cc: Christian Borntraeger Cc: Shawn Guo Cc: Sascha Hauer Cc: Vineet Gupta Cc: "Maciej W. Rozycki" Link: https://lore.kernel.org/r/20210505091928.22010-13-jslaby@suse.cz Signed-off-by: Greg Kroah-Hartman

tty: moxa: fix TIOCSSERIAL implementation

2021-04-07T15:22:07Z

TIOCSSERIAL is a horrid, underspecified, legacy interface which for most serial devices is only useful for setting the close_delay and closing_wait parameters. A non-privileged user has only ever been able to set the since long deprecated ASYNC_SPD flags and trying to change any other *supported* feature should result in -EPERM being returned. Setting the current values for any supported features should return success. Fix the moxa implementation which was returning -EPERM also for a privileged user when trying to change certain unsupported parameters and instead return success consistently. Signed-off-by: Johan Hovold Link: https://lore.kernel.org/r/20210407102334.32361-13-johan@kernel.org Signed-off-by: Greg Kroah-Hartman

tty: moxa: fix TIOCSSERIAL permission check

2021-04-07T15:22:07Z

Changing the port close delay or type are privileged operations so make sure to return -EPERM if a regular user tries to change them. Cc: stable@vger.kernel.org Signed-off-by: Johan Hovold Link: https://lore.kernel.org/r/20210407102334.32361-12-johan@kernel.org Signed-off-by: Greg Kroah-Hartman

tty: moxa: fix TIOCSSERIAL jiffies conversions

2021-04-07T15:22:07Z

The port close_delay parameter set by TIOCSSERIAL is specified in jiffies, while the value returned by TIOCGSERIAL is specified in centiseconds. Add the missing conversions so that TIOCGSERIAL works as expected also when HZ is not 100. Cc: stable@vger.kernel.org Signed-off-by: Johan Hovold Link: https://lore.kernel.org/r/20210407102334.32361-11-johan@kernel.org Signed-off-by: Greg Kroah-Hartman

tty: do not check tty_unregister_driver's return value

2021-03-10T08:34:09Z

These drivers check tty_unregister_driver return value. But they don't handle a failure correctly (they free the driver in any case). So stop checking tty_unregister_driver return value and remove also the prints. In the next patch, tty_unregister_driver's return type will be switched to void. Cc: Chris Zankel Cc: Max Filippov Cc: linux-xtensa@linux-xtensa.org Cc: Jiri Kosina Cc: David Sterba Reviewed-by: Max Filippov Acked-by: David Sterba Signed-off-by: Jiri Slaby Link: https://lore.kernel.org/r/20210302062214.29627-34-jslaby@suse.cz Signed-off-by: Greg Kroah-Hartman

remove ioremap_nocache and devm_ioremap_nocache

2020-01-06T08:45:59Z

ioremap has provided non-cached semantics by default since the Linux 2.6 days, so remove the additional ioremap_nocache interface. Signed-off-by: Christoph Hellwig Acked-by: Arnd Bergmann

moxa: switch to ->[sg]et_serial()

2018-10-13T04:50:32Z

Pointless dead assignments in moxa_set_serial_info() killed off; they would've been a bug, if not for the fact that user-settable flags had never been used in that driver. Bogus from day 1, though... Signed-off-by: Al Viro

tty: moxa: Add support for CMSPAR

2017-11-28T14:32:33Z

The mode constants are taken from the GPL-2.0+ driver available in the driver section of the Moxa homepage. It is tested on a C320Turbo PCI card per logic analyzer and per a device which requires 9 bit character communication. The vendors driver supports CMSPAR unconditionally, so that all other available firmware versions seems to support mark/space parity modes as well. Signed-off-by: Lars Kanis Signed-off-by: Greg Kroah-Hartman