Commit Graph

15 Commits

Author SHA1 Message Date
Geert Uytterhoeven 7e76aece6f auxdisplay: Extract character line display core support
Extract the character line display core support from the simple ASCII
LCD driver for the MIPS Boston, Malta & SEAD3 development boards into
its own subdriver, so it can be reused for other displays.

As this moves the "message" device attribute in sysfs in a "linedisp.N"
subdirectory, a symlink is added to preserve backwards compatibility.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2021-10-21 23:36:28 +02:00
Geert Uytterhoeven 12a19324eb auxdisplay: img-ascii-lcd: Convert device attribute to sysfs_emit()
Convert the "message" device attribute from sprintf() to sysfs_emit(),
as the latter is aware of the PAGE_SIZE buffer.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2021-10-21 23:36:28 +02:00
Geert Uytterhoeven 7b88e5530f auxdisplay: img-ascii-lcd: Add helper variable dev
img_ascii_lcd_probe() has many users of "pdev->dev".  Add a shorthand to
simplify the code.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2021-10-21 23:36:28 +02:00
Geert Uytterhoeven afcb5a811f auxdisplay: img-ascii-lcd: Fix lock-up when displaying empty string
While writing an empty string to a device attribute is a no-op, and thus
does not need explicit safeguards, the user can still write a single
newline to an attribute file:

    echo > .../message

If that happens, img_ascii_lcd_display() trims the newline, yielding an
empty string, and causing an infinite loop in img_ascii_lcd_scroll().

Fix this by adding a check for empty strings.  Clear the display in case
one is encountered.

Fixes: 0cad855fbd ("auxdisplay: img-ascii-lcd: driver for simple ASCII LCD displays")
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2021-10-21 23:36:28 +02:00
Yangtao Li e8897e4fe8 auxdisplay: img-ascii-lcd: convert to devm_platform_ioremap_resource
Use devm_platform_ioremap_resource() to simplify code.

Signed-off-by: Yangtao Li <tiny.windzz@gmail.com>
Signed-off-by: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>
2020-03-06 22:07:10 +01:00
Thomas Gleixner 2874c5fd28 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152
Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation either version 2 of the license or at
  your option any later version

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 3029 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30 11:26:32 -07:00
Miguel Ojeda 26a2c54d03 auxdisplay: img-ascii-lcd: Silence 2 uninitialized warnings
The warnings are:

  drivers/auxdisplay/img-ascii-lcd.c: warning: 'err' may be used
  uninitialized in this function [-Wuninitialized]

At lines 109 and 207. Reported by Geert using the build service
several times, e.g.:

  https://lkml.org/lkml/2018/2/19/303

They are two false positives, since num_chars > 0 in the three present
configurations (boston, malta, sead3). Initialize to 0 in order to
silence the warning.

Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Paul Burton <paul.burton@mips.com>
Signed-off-by: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>
2018-03-13 18:16:38 +01:00
Miguel Ojeda 6a78b4dde1 auxdisplay: img-ascii-lcd: Fix doc comment to silence warnings
Compiling with W=1 with gcc 7.2.0 gives 2 warnings:

  drivers/auxdisplay/img-ascii-lcd.c:233: warning: Function parameter or
  member 't' not described in 'img_ascii_lcd_scroll'
  drivers/auxdisplay/img-ascii-lcd.c:233: warning: Excess function
  parameter 'arg' description in 'img_ascii_lcd_scroll'

Cc: Paul Burton <paul.burton@mips.com>
Signed-off-by: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>
2018-03-13 18:13:34 +01:00
Jesse Chan 09c479f7f1 auxdisplay: img-ascii-lcd: add missing MODULE_DESCRIPTION/AUTHOR/LICENSE
This change resolves a new compile-time warning
when built as a loadable module:

WARNING: modpost: missing MODULE_LICENSE() in drivers/auxdisplay/img-ascii-lcd.o
see include/linux/module.h for more information

This adds the license as "GPL", which matches the header of the file.

MODULE_DESCRIPTION and MODULE_AUTHOR are also added.

Signed-off-by: Jesse Chan <jc@linux.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-01-10 17:50:01 +01:00
Linus Torvalds 2bcc673101 Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timer updates from Thomas Gleixner:
 "Yet another big pile of changes:

   - More year 2038 work from Arnd slowly reaching the point where we
     need to think about the syscalls themself.

   - A new timer function which allows to conditionally (re)arm a timer
     only when it's either not running or the new expiry time is sooner
     than the armed expiry time. This allows to use a single timer for
     multiple timeout requirements w/o caring about the first expiry
     time at the call site.

   - A new NMI safe accessor to clock real time for the printk timestamp
     work. Can be used by tracing, perf as well if required.

   - A large number of timer setup conversions from Kees which got
     collected here because either maintainers requested so or they
     simply got ignored. As Kees pointed out already there are a few
     trivial merge conflicts and some redundant commits which was
     unavoidable due to the size of this conversion effort.

   - Avoid a redundant iteration in the timer wheel softirq processing.

   - Provide a mechanism to treat RTC implementations depending on their
     hardware properties, i.e. don't inflict the write at the 0.5
     seconds boundary which originates from the PC CMOS RTC to all RTCs.
     No functional change as drivers need to be updated separately.

   - The usual small updates to core code clocksource drivers. Nothing
     really exciting"

* 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (111 commits)
  timers: Add a function to start/reduce a timer
  pstore: Use ktime_get_real_fast_ns() instead of __getnstimeofday()
  timer: Prepare to change all DEFINE_TIMER() callbacks
  netfilter: ipvs: Convert timers to use timer_setup()
  scsi: qla2xxx: Convert timers to use timer_setup()
  block/aoe: discover_timer: Convert timers to use timer_setup()
  ide: Convert timers to use timer_setup()
  drbd: Convert timers to use timer_setup()
  mailbox: Convert timers to use timer_setup()
  crypto: Convert timers to use timer_setup()
  drivers/pcmcia: omap1: Fix error in automated timer conversion
  ARM: footbridge: Fix typo in timer conversion
  drivers/sgi-xp: Convert timers to use timer_setup()
  drivers/pcmcia: Convert timers to use timer_setup()
  drivers/memstick: Convert timers to use timer_setup()
  drivers/macintosh: Convert timers to use timer_setup()
  hwrng/xgene-rng: Convert timers to use timer_setup()
  auxdisplay: Convert timers to use timer_setup()
  sparc/led: Convert timers to use timer_setup()
  mips: ip22/32: Convert timers to use timer_setup()
  ...
2017-11-13 17:56:58 -08:00
Paul Burton fb615d61b5 Update MIPS email addresses
MIPS will soon not be a part of Imagination Technologies, and as such
many @imgtec.com email addresses will no longer be valid. This patch
updates the addresses for those who:

 - Have 10 or more patches in mainline authored using an @imgtec.com
   email address, or any patches dated within the past year.

 - Are still with Imagination but leaving as part of the MIPS business
   unit, as determined from an internal email address list.

 - Haven't already updated their email address (ie. JamesH) or expressed
   a desire to be excluded (ie. Maciej).

 - Acked v2 or earlier of this patch, which leaves Deng-Cheng, Matt &
   myself.

New addresses are of the form firstname.lastname@mips.com, and all
verified against an internal email address list.  An entry is added to
.mailmap for each person such that get_maintainer.pl will report the new
addresses rather than @imgtec.com addresses which will soon be dead.

Instances of the affected addresses throughout the tree are then
mechanically replaced with the new @mips.com address.

Signed-off-by: Paul Burton <paul.burton@mips.com>
Cc: Deng-Cheng Zhu <dengcheng.zhu@imgtec.com>
Cc: Deng-Cheng Zhu <dengcheng.zhu@mips.com>
Acked-by: Dengcheng Zhu <dengcheng.zhu@mips.com>
Cc: Matt Redfearn <matt.redfearn@imgtec.com>
Cc: Matt Redfearn <matt.redfearn@mips.com>
Acked-by: Matt Redfearn <matt.redfearn@mips.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: linux-kernel@vger.kernel.org
Cc: linux-mips@linux-mips.org
Cc: trivial@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-03 09:02:30 -07:00
Kees Cook 607a630107 auxdisplay: Convert timers to use timer_setup()
In preparation for unconditionally passing the struct timer_list pointer to
all timer callbacks, switch to using the new timer_setup() and from_timer()
to pass the timer pointer explicitly.

Cc: Paul Burton <paul.burton@imgtec.com>
Cc: Miguel Ojeda Sandonis <miguel.ojeda.sandonis@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Paul Burton <paul.burton@mips.com>
Tested-by: Paul Burton <paul.burton@mips.com> # for img-ascii-lcd
2017-11-02 15:50:37 -07:00
Javier Martinez Canillas 750100a495 auxdisplay: img-ascii-lcd: Fix module autoload
If the driver is built as a module, autoload won't work because the module
alias information is not filled. So user-space can't match the registered
device with the corresponding module.

Export the module alias information using the MODULE_DEVICE_TABLE() macro.

Before this patch:

$ modinfo drivers/auxdisplay/img-ascii-lcd.ko | grep alias
$

After this patch:

$ modinfo drivers/auxdisplay/img-ascii-lcd.ko | grep alias
alias:          of:N*T*Cmti,sead3-lcdC*
alias:          of:N*T*Cmti,sead3-lcd
alias:          of:N*T*Cmti,malta-lcdC*
alias:          of:N*T*Cmti,malta-lcd
alias:          of:N*T*Cimg,boston-lcdC*
alias:          of:N*T*Cimg,boston-lcd

Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-04-08 17:48:20 +02:00
Dmitry Torokhov abda288bb2 auxdisplay: img-ascii-lcd: add missing sentinel entry in img_ascii_lcd_matches
The OF device table must be terminated, otherwise we'll be walking past it
and into areas unknown.

Fixes: 0cad855fbd ("auxdisplay: img-ascii-lcd: driver for simple ASCII...")
Cc: stable@vger.kernel.org
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Tested-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-03-16 16:59:55 +09:00
Paul Burton 0cad855fbd auxdisplay: img-ascii-lcd: driver for simple ASCII LCD displays
Add a driver for simple ASCII LCD displays found on the MIPS Boston,
Malta & SEAD3 development boards. The Boston display is an independent
memory mapped device with a simple memory mapped 8 byte register space
containing the 8 ASCII characters to display. The Malta display is
exposed as part of the Malta board registers, and provides 8 registers
each of which corresponds to one of the ASCII characters to display. The
SEAD3 display is slightly more complex, exposing an interface to an
S6A0069 LCD controller via registers provided by the boards CPLD.
However although the displays differ in their register interface, we
require similar functionality on each board so abstracting away the
differences within a single driver allows us to share a significant
amount of code & ensure consistent behaviour.

The driver displays the Linux kernel version as the default message, but
allows the message to be changed via a character device. Messages longer
then the number of characters that the display can show will scroll.

This provides different behaviour to the existing LCD display code for
the MIPS Malta or MIPS SEAD3 platforms in the following ways:

  - The default string to display is not "LINUX ON MALTA" or "LINUX ON
    SEAD3" but "Linux" followed by the version number of the kernel
    (UTS_RELEASE).

  - Since that string tends to be significantly longer it scrolls twice
    as fast, moving every 500ms rather than every 1s.

  - The LCD won't be updated until the driver is probed, so it doesn't
    provide the early "LINUX" string.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: Mauro Carvalho Chehab <mchehab@kernel.org>
Cc: Miguel Ojeda Sandonis <miguel.ojeda.sandonis@gmail.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: David S. Miller <davem@davemloft.net>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/14062/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-10-06 17:03:41 +02:00