Commit Graph

36 Commits

Author SHA1 Message Date
Fabio Estevam
73e7f1732e Input: imx_keypad - convert to a DT-only driver
i.MX has been converted to a DT-only platform, so make the
adjustments to the driver to convert it to a DT-only driver.

Signed-off-by: Fabio Estevam <festevam@gmail.com>
Link: https://lore.kernel.org/r/20210327194307.541248-1-festevam@gmail.com
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
2021-03-27 21:40:21 -07:00
Andrzej Pietrasiewicz
d69f0a43c6 Input: use input_device_enabled()
Use the newly added helper in relevant input drivers.

Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@collabora.com>
Link: https://lore.kernel.org/r/20200608112211.12125-3-andrzej.p@collabora.com
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
2020-12-02 22:10:33 -08:00
Stephen Boyd
0bec8b7e5c Input: remove dev_err() usage after platform_get_irq()
We don't need dev_err() messages when platform_get_irq() fails now that
platform_get_irq() prints an error message itself when something goes
wrong. Let's remove these prints with a simple semantic patch.

// <smpl>
@@
expression ret;
struct platform_device *E;
@@

ret =
(
platform_get_irq(E, ...)
|
platform_get_irq_byname(E, ...)
);

if ( \( ret < 0 \| ret <= 0 \) )
{
(
-if (ret != -EPROBE_DEFER)
-{ ...
-dev_err(...);
-... }
|
...
-dev_err(...);
)
...
}
// </smpl>

While we're here, remove braces on if statements that only have one
statement (manually).

Signed-off-by: Stephen Boyd <swboyd@chromium.org>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
2019-08-14 10:49:01 -07:00
Dmitry Torokhov
ecb41832bd Linux 5.2
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Merge tag 'v5.2' into next

Sync up with mainline to resolve conflicts in iforce driver.
2019-07-15 09:42:32 -07:00
Anson Huang
ce9a53eb3d Input: imx_keypad - make sure keyboard can always wake up system
There are several scenarios that keyboard can NOT wake up system
from suspend, e.g., if a keyboard is depressed between system
device suspend phase and device noirq suspend phase, the keyboard
ISR will be called and both keyboard depress and release interrupts
will be disabled, then keyboard will no longer be able to wake up
system. Another scenario would be, if a keyboard is kept depressed,
and then system goes into suspend, the expected behavior would be
when keyboard is released, system will be waked up, but current
implementation can NOT achieve that, because both depress and release
interrupts are disabled in ISR, and the event check is still in
progress.

To fix these issues, need to make sure keyboard's depress or release
interrupt is enabled after noirq device suspend phase, this patch
moves the suspend/resume callback to noirq suspend/resume phase, and
enable the corresponding interrupt according to current keyboard status.

Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
2019-06-11 17:52:02 -07:00
Anson Huang
d8ea61c5af Input: imx_keypad - use devm_platform_ioremap_resource() to simplify code
Use the new helper devm_platform_ioremap_resource() which wraps the
platform_get_resource() and devm_ioremap_resource() together, to
simplify the code.

Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
Reviewed-by: Mukesh Ojha <mojha@codeaurora.org>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
2019-05-20 22:45:17 -07:00
Fabio Estevam
0eb7090454 Input: imx_keypad - switch to SPDX identifier
Adopt the SPDX license identifier headers to ease license compliance
management.

Signed-off-by: Fabio Estevam <fabio.estevam@nxp.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
2018-06-21 17:22:06 -07:00
Kees Cook
4ea40278eb Input: keyboard - 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.

Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
2017-10-24 10:04:44 -07:00
Fabio Estevam
ade9c1a47c Input: imx_keypad - remove obsolete comment
Since commit 81e8f2bc (Input: imx_keypad - add pm suspend and resume
support) the imx_keypad driver supports power management, so let's remove
the obsolete comment.

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
2015-09-05 11:49:33 -07:00
Fabio Estevam
e998200c19 Input: imx_keypad - check for clk_prepare_enable() error
clk_prepare_enable() may fail, so we should better check its return value
and propagate it in the case of error.

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
2015-06-22 09:33:51 -07:00
Dmitry Torokhov
0c49cd295d linux 3.19-rc4
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Merge tag 'v3.19-rc4' into next

Merge with mainline to bring in the latest thermal and other changes.
2015-01-15 09:46:14 -08:00
Fabio Estevam
061a5ad7c9 Input: imx_keypad - use the preferred form for passing a size of a struct
According to Documentation/CodingStyle - Chapter 14:

"The preferred form for passing a size of a struct is the following:

        p = kmalloc(sizeof(*p), ...);

The alternative form where struct name is spelled out hurts readability and
introduces an opportunity for a bug when the pointer variable type is changed
but the corresponding sizeof that is passed to a memory allocator is not."

So do it as recommended.

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
2015-01-07 16:02:52 -08:00
Wolfram Sang
1d05726c31 input: keyboard: drop owner assignment from platform_drivers
A platform_driver does not need to set an owner, it will be populated by the
driver core.

Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-10-20 16:20:39 +02:00
Fabio Estevam
e179d5fa8d Input: imx_keypad - remove ifdef round PM methods
We can annotate the suspend/resume functions with '__maybe_unused' and get
rid of the ifdef, which makes the code smaller and simpler.

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
2014-07-31 11:59:34 -07:00
Jingoo Han
27ec39c077 Input: imx_keypad - make of_device_id array const
Make of_device_id array const, because all OF functions handle it as const.

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
2014-05-14 16:39:54 -07:00
Fabio Estevam
7fb45edba8 Input: imx_keypad - Propagate the real error code on platform_get_irq() failure
No need to return a 'fake' return value on platform_get_irq() failure.

Just return the error code itself instead.

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
2014-02-17 11:37:13 -08:00
Paul Gortmaker
bf9a9f8e51 Input: delete non-required instances of include <linux/init.h>
None of these files are actually using any __init type directives
and hence don't need to include <linux/init.h>.  Most are just a
left over from __devinit and __cpuinit removal, or simply due to
code getting copied from one driver to the next.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
2014-01-06 23:23:57 -08:00
Jingoo Han
c838cb3d47 Input: use dev_get_platdata()
Use the wrapper function for retrieving the platform data instead
of accessing dev->platform_data directly. This is a cosmetic change
to make the code simpler and enhance the readability.

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Acked-by: Fugang Duan <B38611@freescale.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
2013-12-06 02:06:29 -08:00
Julia Lawall
ef0aca7f2f Input: keyboard, serio - simplify use of devm_ioremap_resource
Remove unneeded error handling on the result of a call to
platform_get_resource when the value is passed to devm_ioremap_resource.

Move the call to platform_get_resource adjacent to the call to
devm_ioremap_resource to make the connection between them more clear.

A simplified version of the semantic patch that makes this change is as
follows: (http://coccinelle.lip6.fr/)

// <smpl>
@@
expression pdev,res,n,e,e1;
expression ret != 0;
identifier l;
@@

- res = platform_get_resource(pdev, IORESOURCE_MEM, n);
  ... when != res
- if (res == NULL) { ... \(goto l;\|return ret;\) }
  ... when != res
+ res = platform_get_resource(pdev, IORESOURCE_MEM, n);
  e = devm_ioremap_resource(e1, res);
// </smpl>

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
2013-08-15 00:30:17 -07:00
Fabio Estevam
da5bce199f Input: imx_keypad - switch to using managed resources
Using devm_ functions can make the code cleaner and simpler.

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
2013-03-31 00:48:18 -07:00
Liu Ying
0e14235e6c Input: imx_keypad - add device tree support
This patch adds device tree support for imx keypad driver.

Signed-off-by: Liu Ying <Ying.Liu@freescale.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
2013-01-03 12:41:31 -08:00
Andreas Pretzsch
92aab96034 Input: imx_keypad - only set enabled columns to open-drain
In imx_keypad_inhibit(), all 8 columns were set to open-drain, in
contrast to the rest of the driver, where only the enabled columns
are modified/used.

Contrary to the normal expectation, this also affects column I/Os not
even mapped via IOMUX to the KPP hardware module but used as a GPIO.
Therefore only init enabled columns to open-drain and leave all others
with their default reset value of 0, i.e. totem-pole.

Signed-off-by: Andreas Pretzsch <apr@cn-eng.de>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
2012-11-25 00:10:18 -08:00
Bill Pemberton
e2619cf78e Input: remove use of __devexit
CONFIG_HOTPLUG is going away as an option so __devexit is no
longer needed.

Signed-off-by: Bill Pemberton <wfp5p@virginia.edu>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
2012-11-24 00:05:38 -08:00
Bill Pemberton
5298cc4cc7 Input: remove use of __devinit
CONFIG_HOTPLUG is going away as an option so __devinit is no longer
needed.

Signed-off-by: Bill Pemberton <wfp5p@virginia.edu>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Javier Martinez Canillas <javier@dowhile0.org>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
2012-11-24 00:05:19 -08:00
Bill Pemberton
1cb0aa8817 Input: remove use of __devexit_p
CONFIG_HOTPLUG is going away as an option so __devexit_p is no longer
needed.

Signed-off-by: Bill Pemberton <wfp5p@virginia.edu>
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
2012-11-24 00:03:48 -08:00
Fabio Estevam
609455f481 Input: imx_keypad - fix missing clk conversions
commit a1e636e6d3 (Input: imx_keypad - use clk_prepare_enable/
clk_disable_unprepare()) missed to update clk_enable/clk_disable
in imx_keypad_probe().

Fix it so that we do not get clk warnings at boot.

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
2012-09-04 22:18:03 -07:00
Michael Grzeschik
f35dd69ba3 Input: imx_keypad - reset the hardware before enabling
Ensure the hardware is correctly initialized before requesting the
interrupt, otherwise if a key was already touched since power-on the
kernel enters an interrupt loop. To fix this issue we clear pending
interrupt sources. We also have to make sure clk is enabled while
changing the keypad registers.

Signed-off-by: Michael Grzeschik <m.grzeschik@pengutronix.de>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
2012-08-21 22:03:09 -07:00
Fabio Estevam
333fbe8409 Input: imx_keypad - check error returned by clk_prepare_enable()
Check error returned by clk_prepare_enable().

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
2012-07-06 19:12:40 -07:00
Fabio Estevam
a40ec72d54 Input: imx_keypad - adapt the new kpp clock name
With the new i.mx clock framework we should pass NULL as the keypad
clock name.

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
2012-07-06 19:12:35 -07:00
Fabio Estevam
a1e636e6d3 Input: imx_keypad - use clk_prepare_enable/clk_disable_unprepare()
Adapt clock handling to the new i.mx clock framework and fix the following
warning:

input: imx-keypad as /devices/platform/imx-keypad/input/input0
------------[ cut here ]------------
WARNING: at drivers/clk/clk.c:511 __clk_enable+0x98/0xa8()
Modules linked in:
[<c001a680>] (unwind_backtrace+0x0/0xf4) from [<c002452c>] (warn_slowpath_commo)
[<c002452c>] (warn_slowpath_common+0x48/0x60) from [<c0024560>] (warn_slowpath_)
[<c0024560>] (warn_slowpath_null+0x1c/0x24) from [<c02c4ec4>] (__clk_enable+0x9)
[<c02c4ec4>] (__clk_enable+0x98/0xa8) from [<c02c4ef8>] (clk_enable+0x24/0x5c)
[<c02c4ef8>] (clk_enable+0x24/0x5c) from [<c027ac6c>] (imx_keypad_open+0x28/0xc)
[<c027ac6c>] (imx_keypad_open+0x28/0xc8) from [<c0274b14>] (input_open_device+0)
[<c0274b14>] (input_open_device+0x78/0xa8) from [<c01ec884>] (kbd_connect+0x60/)
[<c01ec884>] (kbd_connect+0x60/0x80) from [<c0273b94>] (input_attach_handler+0x)
[<c0273b94>] (input_attach_handler+0x220/0x258) from [<c02755d4>] (input_regist)
[<c02755d4>] (input_register_device+0x31c/0x390) from [<c038da1c>] (imx_keypad_)
[<c038da1c>] (imx_keypad_probe+0x2e4/0x3b8) from [<c020326c>] (platform_drv_pro)
[<c020326c>] (platform_drv_probe+0x18/0x1c) from [<c0201f64>] (driver_probe_dev)
[<c0201f64>] (driver_probe_device+0x84/0x210) from [<c020217c>] (__driver_attac)
[<c020217c>] (__driver_attach+0x8c/0x90) from [<c02008f8>] (bus_for_each_dev+0x)
[<c02008f8>] (bus_for_each_dev+0x68/0x90) from [<c0201064>] (bus_add_driver+0xa)
[<c0201064>] (bus_add_driver+0xa4/0x23c) from [<c020275c>] (driver_register+0x7)
[<c020275c>] (driver_register+0x78/0x12c) from [<c00087c0>] (do_one_initcall+0x)
[<c00087c0>] (do_one_initcall+0x34/0x188) from [<c04b9310>] (kernel_init+0xe4/0)
[<c04b9310>] (kernel_init+0xe4/0x1a8) from [<c0015bd8>] (kernel_thread_exit+0x0)
---[ end trace 1d550e891d03d7ce ]---

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
2012-07-06 19:12:30 -07:00
Dmitry Torokhov
1932811f42 Input: matrix-keymap - uninline and prepare for device tree support
Change matrix-keymap helper to be out-of-line, like sparse keymap,
allow the helper perform basic keymap validation and return errors,
and prepare for device tree support.

Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
2012-05-10 22:38:47 -07:00
JJ Ding
5146c84f87 Input: keyboard - use macro module_platform_driver()
Commit 940ab88962 introduced a new macro to
save some platform_driver boilerplate code. Use it.

Signed-off-by: JJ Ding <dgdunix@gmail.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
2011-11-30 23:41:41 -08:00
Hui Wang
81e8f2bc82 Input: imx_keypad - add pm suspend and resume support
The imx_keypad driver was indicating that it was wakeup capable in
imx_keypad_probe(), but it didn't implement suspend or resume methods.

According to the i.MX series MCU Reference Manual, the kpp (keypad
port) is a major wake up source which can detect any key press even
in low power mode and even when there is no clock.

Signed-off-by: Hui Wang <jason77.wang@gmail.com>
Reviewed-by: Wanlong Gao <gaowanlong@cn.fujitsu.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
2011-10-12 21:13:16 -07:00
Yong Zhang
ec4665c46b Input: remove IRQF_DISABLED from drivers
This flag is a NOOP and can be removed now.

Signed-off-by: Yong Zhang <yong.zhang0@gmail.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
2011-09-07 14:19:11 -07:00
Tejun Heo
5a0e3ad6af include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h
percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files.  percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.

percpu.h -> slab.h dependency is about to be removed.  Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability.  As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.

  http://userweb.kernel.org/~tj/misc/slabh-sweep.py

The script does the followings.

* Scan files for gfp and slab usages and update includes such that
  only the necessary includes are there.  ie. if only gfp is used,
  gfp.h, if slab is used, slab.h.

* When the script inserts a new include, it looks at the include
  blocks and try to put the new include such that its order conforms
  to its surrounding.  It's put in the include block which contains
  core kernel includes, in the same order that the rest are ordered -
  alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
  doesn't seem to be any matching order.

* If the script can't find a place to put a new include (mostly
  because the file doesn't have fitting include block), it prints out
  an error message indicating which .h file needs to be added to the
  file.

The conversion was done in the following steps.

1. The initial automatic conversion of all .c files updated slightly
   over 4000 files, deleting around 700 includes and adding ~480 gfp.h
   and ~3000 slab.h inclusions.  The script emitted errors for ~400
   files.

2. Each error was manually checked.  Some didn't need the inclusion,
   some needed manual addition while adding it to implementation .h or
   embedding .c file was more appropriate for others.  This step added
   inclusions to around 150 files.

3. The script was run again and the output was compared to the edits
   from #2 to make sure no file was left behind.

4. Several build tests were done and a couple of problems were fixed.
   e.g. lib/decompress_*.c used malloc/free() wrappers around slab
   APIs requiring slab.h to be added manually.

5. The script was run on all .h files but without automatically
   editing them as sprinkling gfp.h and slab.h inclusions around .h
   files could easily lead to inclusion dependency hell.  Most gfp.h
   inclusion directives were ignored as stuff from gfp.h was usually
   wildly available and often used in preprocessor macros.  Each
   slab.h inclusion directive was examined and added manually as
   necessary.

6. percpu.h was updated not to include slab.h.

7. Build test were done on the following configurations and failures
   were fixed.  CONFIG_GCOV_KERNEL was turned off for all tests (as my
   distributed build env didn't work with gcov compiles) and a few
   more options had to be turned off depending on archs to make things
   build (like ipr on powerpc/64 which failed due to missing writeq).

   * x86 and x86_64 UP and SMP allmodconfig and a custom test config.
   * powerpc and powerpc64 SMP allmodconfig
   * sparc and sparc64 SMP allmodconfig
   * ia64 SMP allmodconfig
   * s390 SMP allmodconfig
   * alpha SMP allmodconfig
   * um on x86_64 SMP allmodconfig

8. percpu.h modifications were reverted so that it could be applied as
   a separate patch and serve as bisection point.

Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.

Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-30 22:02:32 +09:00
Alberto Panizzo
76cdc083f4 Input: add imx-keypad driver to support the IMX Keypad Port
The IMX family of Application Processors is shipped with a Keypad Port
supported by this driver.

The peripheral can control up to an 8x8 matrix key pad where all the
scanning is done via software.  The hardware provides two interrupts:
one for key presses (KDI) and one for all key releases (KRI). There is
also a simple circuit for glitch reduction (said for synchronization)
made by two series of 3 D-latches clocked by the keypad-clock that
stabilize the interrupts sources. KDI and KRI are fired only if the
respective conditions are maintained for at last 4 keypad-clock cycle.

Since those circuits are poor for a correct debounce process (the
keypad-clock frequency is 32K and bounces longer than 94us are not
masked) the driver, when an interrupt arrives, samples the matrix
with a period of 10ms until the readins are stable for
IMX_KEYPAD_SCANS_FOR_STABILITY times (currently set at 3). After
getting stable result appropriate events are sent through the input
stack.

If some keys are maintained pressed, the driver continues to scan
the matrix with a longer period (60ms) to catch possible multiple
key presses without overloading the cpu. This process ends when all
keys are released.

This driver is tested to build in kernel or as a module and follow
the specification of Freescale Application processors:
i.MX25 i.MX27 i.MX31 i.MX35 i.MX51 especially tested on i.MX31.

Signed-off-by: Alberto Panizzo <maramaopercheseimorto@gmail.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
2010-01-31 17:52:57 -08:00