7 Commits

Author SHA1 Message Date
AngeloGioacchino Del Regno
58e0264658 pwm: mtk-disp: Disable shadow registers before setting backlight values
[ Upstream commit 36dd7f530ae7d9ce9e853ffb8aa337de65c6600b ]

If shadow registers usage is not desired, disable that before performing
any write to CON0/1 registers in the .apply() callback, otherwise we may
lose clkdiv or period/width updates.

Fixes: cd4b45ac449a ("pwm: Add MediaTek MT2701 display PWM driver support")
Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Reviewed-by: Nícolas F. R. A. Prado <nfraprado@collabora.com>
Tested-by: Nícolas F. R. A. Prado <nfraprado@collabora.com>
Reviewed-by: Alexandre Mergnat <amergnat@baylibre.com>
Tested-by: Alexandre Mergnat <amergnat@baylibre.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-05-17 11:35:53 +02:00
Jitao Shi
33f00f0a73 pwm: mtk-disp: Adjust the clocks to avoid them mismatch
[ Upstream commit d7a4e582587d97a586b1f7709e3bddcf35928e96 ]

The clks "main" and "mm" are prepared in .probe() (and unprepared in
.remove()). This results in the clocks being on during suspend which
results in unnecessarily increased power consumption.

Remove the clock operations from .probe() and .remove(). Add the
clk_prepare_enable() in .enable() and the clk_disable_unprepare() in
.disable().

Signed-off-by: Jitao Shi <jitao.shi@mediatek.com>
[thierry.reding@gmail.com: squashed in fixup patch]
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Stable-dep-of: 36dd7f530ae7 ("pwm: mtk-disp: Disable shadow registers before setting backlight values")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-05-17 11:35:53 +02:00
Uwe Kleine-König
e5e9e59c45 pwm: mtk-disp: Don't check the return code of pwmchip_remove()
[ Upstream commit 9b7b5736ffd5da6f8f6329ebe5f1829cbcf8afae ]

pwmchip_remove() returns always 0. Don't use the value to make it
possible to eventually change the function to return void. Also the
driver core ignores the return value of mtk_disp_pwm_remove().

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Stable-dep-of: 36dd7f530ae7 ("pwm: mtk-disp: Disable shadow registers before setting backlight values")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-05-17 11:35:53 +02:00
Thomas Gleixner
1802d0beec treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 174
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 version 2 as
  published by the free software foundation this program is
  distributed in the hope that it will be useful but without any
  warranty without even the implied warranty of merchantability or
  fitness for a particular purpose see the gnu general public license
  for more details

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 655 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070034.575739538@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30 11:26:41 -07:00
Jitao Shi
a87b40615a pwm: Add MediaTek MT8183 display PWM driver support
Use the mtk_pwm_data struction to define different registers
and add MT8183 specific register operations, such as MT8183
doesn't have commit register, needs to disable double buffer
before writing register, and needs to select commit mode
and use PWM_PERIOD/PWM_HIGH_WIDTH.

Signed-off-by: Jitao Shi <jitao.shi@mediatek.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2019-03-04 11:45:08 +01:00
Weiqing Kong
cd4b45ac44 pwm: Add MediaTek MT2701 display PWM driver support
Use the mtk_pwm_data struction to define different registers
and add MT2701 specific register operations, such as MT2701
doesn't have commit register, needs to disable double buffer
before writing register, and needs to select manual mode
and use PWM_PERIOD/PWM_HIGH_WIDTH.

Signed-off-by: Weiqing Kong <weiqing.kong@mediatek.com>
[thierry.reding@gmail.com: use of_device_get_match_data()]
[thierry.reding@gmail.com: parameterize more consistently]
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2016-09-06 10:48:53 +02:00
YH Huang
7e3b7dc76c pwm: Add MediaTek display PWM driver support
Add display PWM driver support to modify backlight for MT8173 and
MT6595. The PWM has one channel to control the brightness of the
display. When the (high_width / period) is closer to 1, the screen
is brighter; otherwise, it is darker.

Signed-off-by: YH Huang <yh.huang@mediatek.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2015-10-06 16:07:30 +02:00