The value returned by an i2c driver's remove function is mostly ignored.
(Only an error message is printed if the value is non-zero that the
error is ignored.)
So change the prototype of the remove function to return no value. This
way driver authors are not tempted to assume that passing an error to
the upper layer is a good idea. All drivers are adapted accordingly.
There is no intended change of behaviour, all callbacks were prepared to
return 0 before.
Reviewed-by: Peter Senna Tschudin <peter.senna@gmail.com>
Reviewed-by: Jeremy Kerr <jk@codeconstruct.com.au>
Reviewed-by: Benjamin Mugnier <benjamin.mugnier@foss.st.com>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Reviewed-by: Crt Mori <cmo@melexis.com>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Marek Behún <kabel@kernel.org> # for leds-turris-omnia
Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Petr Machata <petrm@nvidia.com> # for mlxsw
Reviewed-by: Maximilian Luz <luzmaximilian@gmail.com> # for surface3_power
Acked-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> # for bmc150-accel-i2c + kxcjk-1013
Reviewed-by: Hans Verkuil <hverkuil-cisco@xs4all.nl> # for media/* + staging/media/*
Acked-by: Miguel Ojeda <ojeda@kernel.org> # for auxdisplay/ht16k33 + auxdisplay/lcd2s
Reviewed-by: Luca Ceresoli <luca.ceresoli@bootlin.com> # for versaclock5
Reviewed-by: Ajay Gupta <ajayg@nvidia.com> # for ucsi_ccg
Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> # for iio
Acked-by: Peter Rosin <peda@axentia.se> # for i2c-mux-*, max9860
Acked-by: Adrien Grassein <adrien.grassein@gmail.com> # for lontium-lt8912b
Reviewed-by: Jean Delvare <jdelvare@suse.de> # for hwmon, i2c-core and i2c/muxes
Acked-by: Corey Minyard <cminyard@mvista.com> # for IPMI
Reviewed-by: Vladimir Oltean <olteanv@gmail.com>
Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Acked-by: Sebastian Reichel <sebastian.reichel@collabora.com> # for drivers/power
Acked-by: Krzysztof Hałasa <khalasa@piap.pl>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
ht16k33.c doesn't use any macro or function declared in
linux/slab.h. Thus, these files can be removed from ht16k33.c
safely without affecting the compilation.
Signed-off-by: Mianhan Liu <liumh1@shanghaitech.edu.cn>
Acked-by: Robin van der Gracht <robin@protonic.nl>
[reworded]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
The device property API allows drivers to gather device resources from
different sources, such as ACPI, and lift the dependency on Device Tree.
Convert the driver to unleash the power of the device property API.
Suggested-by: Marek Behún <kabel@kernel.org>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Acked-by: Robin van der Gracht <robin@protonic.nl>
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Instantiate a single LED based on the "led" subnode in DT.
This allows the user to control display brightness and blinking (backed
by hardware support) through the LED class API and triggers, and exposes
the display color. The LED will be named
"auxdisplay:<color>:<function>".
When running in dot-matrix mode and if no "led" subnode is found, the
driver falls back to the traditional backlight mode, to preserve
backwards compatibility.
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Reviewed-by: Marek Behún <kabel@kernel.org>
Reviewed-by: Robin van der Gracht <robin@protonic.nl>
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
The Holtek HT16K33 LED controller is not only used for driving
dot-matrix displays, but also for driving segment displays.
Add support for 4-digit 7-segment and quad 14-segment alphanumeric
displays, like the Adafruit 7-segment and 14-segment display backpack
and FeatherWing expansion boards. Use the character line display core
support to display a message, which will be scrolled if it doesn't fit.
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Robin van der Gracht <robin@protonic.nl>
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Extract all frame buffer (including backlight) probing into
ht16k33_fbdev_probe().
Call ht16k33_fbdev_probe() after ht16k33_keypad_probe(), as the latter
does not need any manual cleanup in the probe error path.
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Reviewed-by: Robin van der Gracht <robin@protonic.nl>
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Extract brightness handling into a helper function, so it can be called
from multiple places.
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Reviewed-by: Robin van der Gracht <robin@protonic.nl>
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Move delayed_work from ht16k33_fbdev to ht16k33_priv, as it is not
specific to dot-matrix displays, but common to all display types.
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Robin van der Gracht <robin@protonic.nl>
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
This driver has many users of "client->dev". Add shorthands to simplify
the code.
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Robin van der Gracht <robin@protonic.nl>
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
ht16k33_probe() does not use the passed i2c_device_id, so the driver can
be converted trivially to the new-style of i2c probing.
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Robin van der Gracht <robin@protonic.nl>
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
There is no need to check the return code of input_register_device(),
just propagate it to the caller.
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Robin van der Gracht <robin@protonic.nl>
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Use the existing HT16K33_FB_SIZE definition instead of open-coding the
same calculation using an hardcoded value.
While at it, restore reverse Christmas tree variable declaration order.
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Robin van der Gracht <robin@protonic.nl>
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
As the ht16k33 frame buffer sub-driver does not register an
fb_ops.fb_blank() handler, blanking does not work:
$ echo 1 > /sys/class/graphics/fb0/blank
sh: write error: Invalid argument
Fix this by providing a handler that always returns zero, to make sure
blank events will be sent to the actual device handling the backlight.
Reported-by: Robin van der Gracht <robin@protonic.nl>
Suggested-by: Robin van der Gracht <robin@protonic.nl>
Fixes: 8992da44c6 ("auxdisplay: ht16k33: Driver for LED controller")
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Currently /sys/class/graphics/fb0/bl_curve is not accessible (-ENODEV),
as the driver does not connect the backlight to the frame buffer device.
Fix this moving backlight initialization up, and filling in
fb_info.bl_dev.
Fixes: 8992da44c6 ("auxdisplay: ht16k33: Driver for LED controller")
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Reviewed-by: Robin van der Gracht <robin@protonic.nl>
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Drop the call to msecs_to_jiffies(), as "HZ / fbdev->refresh_rate" is
already the number of jiffies to wait.
Fixes: 8992da44c6 ("auxdisplay: ht16k33: Driver for LED controller")
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Keyscan should be optional to support simple LED matrix displays (output
only).
Reported-by: Michael Kaplan <M.KAPLAN@evva.com>
Signed-off-by: Robin van der Gracht <robin@protonic.nl>
[geert: Rebased]
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Robin van der Gracht <robin@protonic.nl>
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Now that the fbops member of struct fb_info is const, we can start
making the ops const as well.
Cc: Miguel Ojeda Sandonis <miguel.ojeda.sandonis@gmail.com>
Cc: Robin van der Gracht <robin@protonic.nl>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>
Acked-by: Robin van der Gracht <robin@protonic.nl>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/31c18e3ce9d6962aabda4799b3051039ff591c92.1575390741.git.jani.nikula@intel.com
The static structures ht16k33_fb_fix and ht16k33_fb_var, of types
fb_fix_screeninfo and fb_var_screeninfo respectively, are not used
except to be copied into other variables. Hence make both of them
constant to prevent unintended modification.
Issue found with
Coccinelle.
Acked-by: Robin van der Gracht <robin@protonic.nl>
Signed-off-by: Nishka Dasgupta <nishkadg.linux@gmail.com>
Signed-off-by: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>
While using mmap, the incorrect values of length and vm_pgoff are
ignored and this driver goes ahead with mapping fbdev.buffer
to user vma.
Convert vm_insert_pages() to use vm_map_pages_zero(). We could later
"fix" these drivers to behave according to the normal vm_pgoff
offsetting simply by removing the _zero suffix on the function name
and if that causes regressions, it gives us an easy way to revert.
Signed-off-by: Souptick Joarder <jrdr.linux@gmail.com>
Acked-by: Robin van der Gracht <robin@protonic.nl>
Signed-off-by: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>
On module unload/remove, we need to ensure that work does not run
after we have freed resources. Concretely, cancel_delayed_work()
may return while the callback function is still running.
From kernel/workqueue.c:
The work callback function may still be running on return,
unless it returns true and the work doesn't re-arm itself.
Explicitly flush or use cancel_delayed_work_sync() to wait on it.
Link: https://lore.kernel.org/lkml/20190204220952.30761-1-TheSven73@googlemail.com/
Reported-by: Sven Van Asbroeck <thesven73@gmail.com>
Reviewed-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Reviewed-by: Sven Van Asbroeck <TheSven73@gmail.com>
Acked-by: Robin van der Gracht <robin@protonic.nl>
Signed-off-by: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>
The data read from the device is 3 little-endian words, so let's
annotate them as such and use le16_to_cpu() to convert them to host
endianness - it might turn out to be a bit more performant, and it
expresses the conversion more clearly.
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
gcc-7.0.1 points out that we copy uninitialized data from the stack
into a per-device structure:
drivers/auxdisplay/ht16k33.c: In function 'ht16k33_keypad_irq_thread':
arch/x86/include/asm/string_32.h:78:16: error: 'new_state' may be used uninitialized in this function [-Werror=maybe-uninitialized]
arch/x86/include/asm/string_32.h:79:22: error: '*((void *)&new_state+4)' may be used uninitialized in this function [-Werror=maybe-uninitialized]
The access is harmless because we never read the data, but we are better
off not doing this, so this changes the code to only copy the data
that was actually initialized. To make sure we don't overflow the
stack with an incorrect DT, we also need to add a sanity checkin the
probe function.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Robin van der Gracht <robin@protonic.nl>
Reviewed-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
There is no need for the driver to use private workqueue, standard system
workqueue should suffice as they are going to use the same worker pool
anyway.
Acked-by: Robin van der Gracht <robin@protonic.nl>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This patch fixes following issues in input device (keypad) handling:
- requesting IRQ before allocating and initializing parts of the device
that can be referenced from IRQ handler is racy, even if we try to
disable interrupt after requesting it. Let's move allocations around
so that everything is ready by the time we request IRQ.
- using threaded interrupt handler to schedule a work item it sub-optimal.
Disabling and then re-enabling interrupts in work item and in open/close
methods is prone to races and exactly the reason theraded interrupts were
introduced. Let's use the infrastructure properly and keep scanning the
matrix array in IRQ thread, stopping when there are no keys, or when told
to do so.
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Tested-by: Robin van der Gracht <robin@protonic.nl>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
'fbdev' is allocated as part of larger ht16k33_priv structure; trying to
free it will cause troubles.
Acked-by: Robin van der Gracht <robin@protonic.nl>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Added a driver for the Holtek HT16K33 LED controller with keyscan.
Signed-off-by: Robin van der Gracht <robin@protonic.nl>
CC: Miguel Ojeda Sandonis <miguel.ojeda.sandonis@gmail.com>
Acked-by: Rob Herring <robh@kernel.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
