linux-stable.git/drivers/auxdisplay, branch v4.13.7

auxdisplay: charlcd: properly restore atomic counter on error path

2017-10-12T09:56:15+00:00

commit 93dc1774d2a4c7a298d5cdf78cc8acdcb7b1428d upstream.

Commit f4757af ("staging: panel: Fix single-open policy race condition")
introduced in 3.19-rc1 attempted to fix a race condition on the open, but
failed to properly do it and used to exit without restoring the semaphore.

This results in -EBUSY being returned after the first open error until
the module is reloaded or the system restarted (ie: consecutive to a
dual open resulting in -EBUSY or to a permission error).

[ Note for stable maintainers: the code moved from drivers/misc/panel.c
  to drivers/auxdisplay/{charlcd,panel}.c during 4.12. The patch easily
  applies there (modulo the renamed atomic counter) but I can provide a
  tested backport if desired. ]

Fixes: f4757af85 # 3.19-rc1
Cc: Mariusz Gorski 
Cc: Geert Uytterhoeven 
Cc: Miguel Ojeda Sandonis 
Signed-off-by: Willy Tarreau 
Signed-off-by: Greg Kroah-Hartman

auxdisplay: Convert list_for_each to entry variant

2017-05-25T16:24:03+00:00

convert list_for_each() to list_for_each_entry() where
applicable.

Signed-off-by: Wei Yongjun 
Reviewed-by: Andy Shevchenko 
Signed-off-by: Greg Kroah-Hartman

auxdisplay: Move arm-charlcd.c to drivers/auxdisplay folder

2017-04-08T15:48:20+00:00

It looks like arm-charlcd.c belongs to auxdisplay subsystem.

Move it to drivers/auxdisplay folder.
No functional changes intended.

Reviewed-by: Linus Walleij 
Signed-off-by: Andy Shevchenko 
Signed-off-by: Greg Kroah-Hartman

auxdisplay: Move panel.c to drivers/auxdisplay folder

2017-04-08T15:48:20+00:00

It looks like panel.c belongs to auxdisplay subsystem.

Move it to drivers/auxdisplay folder.
No functional changes intended.

Acked-by: Geert Uytterhoeven 
Signed-off-by: Andy Shevchenko 
Signed-off-by: Greg Kroah-Hartman

auxdisplay: ht16k33: use le16_to_cpup() to fetch LE16 data

2017-04-08T15:48:20+00:00

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 
Signed-off-by: Greg Kroah-Hartman

auxdisplay: img-ascii-lcd: Fix module autoload

2017-04-08T15:48:20+00:00

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 
Signed-off-by: Greg Kroah-Hartman

auxdisplay: ht16k33: don't access uninitialized data

2017-04-08T15:48:19+00:00

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 
Reviewed-by: Robin van der Gracht 
Reviewed-by: Dmitry Torokhov 
Signed-off-by: Greg Kroah-Hartman

auxdisplay: hd44780: Fix DT properties to include units of measurement

2017-04-08T15:48:19+00:00

DT properties specifying physical properties should contain appropriate
suffices indicating the units of measurement.

Hence amend the HD44780 DT bindings to add "chars" suffixes to the
"display-height" and "display-width" properties, and update the driver
to parse them.

Fixes: dd9502a9e9156dd8 ("dt-bindings: auxdisplay: Add bindings for Hitachi HD44780")
Fixes: d47d88361feea2ce ("auxdisplay: Add HD44780 Character LCD support")
Signed-off-by: Geert Uytterhoeven 
Acked-by: Rob Herring 
Signed-off-by: Greg Kroah-Hartman

Merge 4.11-rc4 into char-misc-next

2017-03-27T07:13:04+00:00

We want the char-misc fixes in here as well.

Signed-off-by: Greg Kroah-Hartman

auxdisplay: Add HD44780 Character LCD support

2017-03-17T06:10:50+00:00

The Hitachi HD44780 Character LCD Controller is commonly used on
character LCDs that can display one or more lines of text.

This driver supports character LCDs connected to GPIOs, using either a
4-bit or 8-bit data bus, and provides access through the charlcd core
and /dev/lcd.

Signed-off-by: Geert Uytterhoeven 
Signed-off-by: Greg Kroah-Hartman