linux.git/drivers/video/fbdev/ssd1307fb.c, branch v5.8 Linux kernel source tree video: ssd1307fb: Remove redundant forward declaration 2020-04-17T13:50:00+00:00 Andy Shevchenko andriy.shevchenko@linux.intel.com 2020-03-24T17:05:32+00:00 304d63d4d89dc2c24bdfc7730355ca38f589f91b There is no need to have forward declaration of struct ssd1307fb_par. Drop it for good. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> Link: https://patchwork.freedesktop.org/patch/msgid/20200324170532.44384-5-andriy.shevchenko@linux.intel.com 
There is no need to have forward declaration of struct ssd1307fb_par.
Drop it for good.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200324170532.44384-5-andriy.shevchenko@linux.intel.com
video: ssd1307fb: Convert to atomic PWM API 2020-04-17T13:49:59+00:00 Andy Shevchenko andriy.shevchenko@linux.intel.com 2020-03-24T17:05:31+00:00 479382360da64e5d31509c72a07e4623ed249db0 Use the atomic API wherever appropriate and get rid of pwm_apply_args() call (the reference period and polarity are now explicitly set when calling pwm_apply_state()). We also make use of the pwm_set_relative_duty_cycle() helper to ease relative to absolute duty_cycle conversion. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> Link: https://patchwork.freedesktop.org/patch/msgid/20200324170532.44384-4-andriy.shevchenko@linux.intel.com 
Use the atomic API wherever appropriate and get rid of pwm_apply_args()
call (the reference period and polarity are now explicitly set when
calling pwm_apply_state()).

We also make use of the pwm_set_relative_duty_cycle() helper to ease
relative to absolute duty_cycle conversion.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200324170532.44384-4-andriy.shevchenko@linux.intel.com
video: ssd1307fb: Make use of device properties 2020-04-17T13:49:58+00:00 Andy Shevchenko andriy.shevchenko@linux.intel.com 2020-03-24T17:05:30+00:00 72915994e028912add23afce7f16ebd06d2dc73e Device property API allows to gather device resources from different sources, such as ACPI. Convert the drivers to unleash the power of device property API. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> Link: https://patchwork.freedesktop.org/patch/msgid/20200324170532.44384-3-andriy.shevchenko@linux.intel.com 
Device property API allows to gather device resources from different sources,
such as ACPI. Convert the drivers to unleash the power of device property API.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200324170532.44384-3-andriy.shevchenko@linux.intel.com
video: ssd1307fb: Introduce temporary variable to increase readability 2020-04-17T13:49:57+00:00 Andy Shevchenko andriy.shevchenko@linux.intel.com 2020-03-24T17:05:29+00:00 fa64c6badea4445895362fca61c7743ca7cd0bde Introduce temporary variable to increase readability of the code. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> [b.zolnierkie: fix lines over 80 characters] Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> Link: https://patchwork.freedesktop.org/patch/msgid/20200324170532.44384-2-andriy.shevchenko@linux.intel.com 
Introduce temporary variable to increase readability of the code.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
[b.zolnierkie: fix lines over 80 characters]
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200324170532.44384-2-andriy.shevchenko@linux.intel.com
video: ssd1307fb: Convert driver to use ->probe_new() 2020-04-17T13:49:56+00:00 Andy Shevchenko andriy.shevchenko@linux.intel.com 2020-03-24T17:05:28+00:00 59d961c5972f8dd064277b41be1061e41827c726 Use the ->probe_new() callback. The driver does not use const struct i2c_device_id * argument, so convert it to utilise the simplified I²C driver registration. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> Link: https://patchwork.freedesktop.org/patch/msgid/20200324170532.44384-1-andriy.shevchenko@linux.intel.com 
Use the ->probe_new() callback.

The driver does not use const struct i2c_device_id * argument,
so convert it to utilise the simplified I²C driver registration.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200324170532.44384-1-andriy.shevchenko@linux.intel.com
video: Replace zero-length array with flexible-array member 2020-03-02T15:32:17+00:00 Gustavo A. R. Silva gustavo@embeddedor.com 2020-02-21T16:00:05+00:00 451787d3e2ac3a25abae91792b7154ee533b65c6 The current codebase makes use of the zero-length array language extension to the C90 standard, but the preferred mechanism to declare variable-length types such as these ones is a flexible array member[1][2], introduced in C99: struct foo { int stuff; struct boo array[]; }; By making use of the mechanism above, we will get a compiler warning in case the flexible array does not occur last in the structure, which will help us prevent some kind of undefined behavior bugs from being inadvertently introduced[3] to the codebase from now on. Also, notice that, dynamic memory allocations won't be affected by this change: "Flexible array members have incomplete type, and so the sizeof operator may not be applied. As a quirk of the original implementation of zero-length arrays, sizeof evaluates to zero."[1] This issue was found with the help of Coccinelle. [1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html [2] https://github.com/KSPP/linux/issues/21 [3] commit 76497732932f ("cxgb3/l2t: Fix undefined behaviour") Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com> Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> Link: https://patchwork.freedesktop.org/patch/msgid/20200221160005.GA13552@embeddedor 
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:

struct foo {
        int stuff;
        struct boo array[];
};

By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.

Also, notice that, dynamic memory allocations won't be affected by
this change:

"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]

This issue was found with the help of Coccinelle.

[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 76497732932f ("cxgb3/l2t: Fix undefined behaviour")

Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200221160005.GA13552@embeddedor
video: ssd1307fb: add the missed regulator_disable 2020-01-15T16:31:42+00:00 Chuhong Yuan hslester96@gmail.com 2019-11-18T11:41:50+00:00 ac0c2558161d7bf273fcf980d291eb338f47787b The driver forgets to disable the regulator in remove like what is done in probe failure. Add the missed call to fix it. Signed-off-by: Chuhong Yuan <hslester96@gmail.com> Tested-by: Michal Vokáč <michal.vokac@ysoft.com> Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> Link: https://patchwork.freedesktop.org/patch/msgid/20191118114150.25724-1-hslester96@gmail.com 
The driver forgets to disable the regulator in remove like what is done
in probe failure.
Add the missed call to fix it.

Signed-off-by: Chuhong Yuan <hslester96@gmail.com>
Tested-by: Michal Vokáč <michal.vokac@ysoft.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191118114150.25724-1-hslester96@gmail.com
video: constify fb ops across all drivers 2019-12-05T08:57:53+00:00 Jani Nikula jani.nikula@intel.com 2019-12-03T16:38:50+00:00 8a48ac339398f21282985bff16552447d41dcfb2 Now that the fbops member of struct fb_info is const, we can start making the ops const as well. This does not cover all drivers; some actually modify the fbops struct, for example to adjust for different configurations, and others do more involved things that I'd rather not touch in practically obsolete drivers. Mostly this is the low hanging fruit where we can add "const" and be done with it. v3: - un-constify atyfb, mb862xx, nvidia and uvesabf (0day) v2: - fix typo (Christophe de Dinechin) - use "static const" instead of "const static" in mx3fb.c - also constify smscufx.c Cc: linux-fbdev@vger.kernel.org Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch> Signed-off-by: Jani Nikula <jani.nikula@intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/ce67f14435f3af498f2e8bf35ce4be11f7504132.1575390740.git.jani.nikula@intel.com 
Now that the fbops member of struct fb_info is const, we can start
making the ops const as well.

This does not cover all drivers; some actually modify the fbops struct,
for example to adjust for different configurations, and others do more
involved things that I'd rather not touch in practically obsolete
drivers. Mostly this is the low hanging fruit where we can add "const"
and be done with it.

v3:
- un-constify atyfb, mb862xx, nvidia and uvesabf (0day)

v2:
- fix typo (Christophe de Dinechin)
- use "static const" instead of "const static" in mx3fb.c
- also constify smscufx.c

Cc: linux-fbdev@vger.kernel.org
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/ce67f14435f3af498f2e8bf35ce4be11f7504132.1575390740.git.jani.nikula@intel.com
video: ssd1307fb: Add devicetree configuration of display setup 2019-07-23T15:26:56+00:00 Marko Kohtala marko.kohtala@okoko.fi 2019-06-18T07:41:11+00:00 de6786bee48e6f29846b7b220ecfea32364117d4 Various displays have differences that only mean initializing the display driver IC with different fixed register values. Defining these in devicetree offers easier way to adapt the driver to new displays than requiring a patch to the kernel. This adds devicetree properties needed to make the initialization match the example setup as offered by Densitron for their 128x36 display. It also makes some old one bit parameter handling a little cleaner. Signed-off-by: Marko Kohtala <marko.kohtala@okoko.fi> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Rob Herring <robh+dt@kernel.org> Cc: Daniel Vetter <daniel@ffwll.ch> Cc: David Airlie <airlied@linux.ie> Cc: Michal Vokáč <michal.vokac@ysoft.com> [b.zolnierkie: fix parenthesis alignment] Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> Link: https://patchwork.freedesktop.org/patch/msgid/20190618074111.9309-7-marko.kohtala@okoko.fi 
Various displays have differences that only mean initializing the display
driver IC with different fixed register values. Defining these in
devicetree offers easier way to adapt the driver to new displays than
requiring a patch to the kernel.

This adds devicetree properties needed to make the initialization match
the example setup as offered by Densitron for their 128x36 display.

It also makes some old one bit parameter handling a little cleaner.

Signed-off-by: Marko Kohtala <marko.kohtala@okoko.fi>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: David Airlie <airlied@linux.ie>
Cc: Michal Vokáč <michal.vokac@ysoft.com>
[b.zolnierkie: fix parenthesis alignment]
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190618074111.9309-7-marko.kohtala@okoko.fi
video: ssd1307fb: Handle width and height that are not multiple of 8 2019-07-23T15:18:19+00:00 Marko Kohtala marko.kohtala@okoko.fi 2019-06-18T07:41:09+00:00 b0020d8af991a904de57dbd9a7bc7a61982a6a8c Some displays have dimensions that are not multiple of eight, for example height of 36, but the driver divided the dimensions by 8. Defining display to the next multiple of 8 is not good as then the display registers get configured to dimensions that do not match. This contradicts intructions by some display manufacturers. Use DIV_ROUND_UP to multiple of 8 when needed so correct values can be used. The ssd1307fb_update_display bit reordering receives a simplification in the process. Signed-off-by: Marko Kohtala <marko.kohtala@okoko.fi> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Rob Herring <robh+dt@kernel.org> Cc: Daniel Vetter <daniel@ffwll.ch> Cc: David Airlie <airlied@linux.ie> Cc: Michal Vokáč <michal.vokac@ysoft.com> Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> Link: https://patchwork.freedesktop.org/patch/msgid/20190618074111.9309-5-marko.kohtala@okoko.fi 
Some displays have dimensions that are not multiple of eight, for example
height of 36, but the driver divided the dimensions by 8. Defining display
to the next multiple of 8 is not good as then the display registers get
configured to dimensions that do not match. This contradicts intructions
by some display manufacturers.

Use DIV_ROUND_UP to multiple of 8 when needed so correct values can be
used.

The ssd1307fb_update_display bit reordering receives a simplification in
the process.

Signed-off-by: Marko Kohtala <marko.kohtala@okoko.fi>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: David Airlie <airlied@linux.ie>
Cc: Michal Vokáč <michal.vokac@ysoft.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190618074111.9309-5-marko.kohtala@okoko.fi