Commit graph

13 commits

Author SHA1 Message Date
Alper Nebi Yasak
1b9ee2882e pwm: Add a driver for Chrome OS EC PWM
This PWM is used in rk3399-gru-bob and rk3399-gru-kevin to control
the display brightness. We can only change the duty cycle, so on
set_config() we just try to match the duty cycle that dividing duty_ns
by period_ns gives us. To disable, we set the duty cycle to zero while
keeping the old value for when we want to re-enable it.

The cros_ec_set_pwm_duty() function is taken from Depthcharge's
cros_ec_set_bl_pwm_duty() but modified to use the generic pwm type.
The driver itself is very loosely based on rk_pwm.c for the general pwm
driver structure.

The devicetree binding file is from Linux, before it was converted to
YAML at 5df5a577a6b4 ("dt-bindings: pwm: Convert google,cros-ec-pwm.txt
to YAML format") in their repo.

Signed-off-by: Alper Nebi Yasak <alpernebiyasak@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
2021-04-10 16:08:39 +02:00
Dario Binacchi
ade7f0d00e pwm: ti: am33xx: add enhanced pwm driver
Enhanced high resolution PWM module (EHRPWM) hardware can be used to
generate PWM output over 2 channels. This commit adds PWM driver support
for EHRPWM device present on AM33XX SOC.

The code is based on the drivers/pwm/pwm-tiehrpwm.c driver of the Linux
kernel version 5.9-rc7.
For DT binding details see:
- Documentation/devicetree/bindings/pwm/pwm-tiehrpwm.txt

Signed-off-by: Dario Binacchi <dariobin@libero.it>
2021-01-12 10:58:05 +05:30
Neil Armstrong
2d481b2e3e pwm: Add driver for Amlogic Meson PWM controller
This adds the driver for the PWM controller found in the Amlogic SoCs.

This PWM is only a set of Gates, Dividers and Counters:
PWM output is achieved by calculating a clock that permits calculating
two periods (low and high). The counter then has to be set to switch after
N cycles for the first half period.
The hardware has no "polarity" setting. This driver reverses the period
cycles (the low length is inverted with the high length) for
PWM_POLARITY_INVERSED.

Disabling the PWM stops the output immediately (without waiting for the
current period to complete first).

Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
2020-10-05 18:02:16 +02:00
Yash Shah
7239a610b7 pwm: Add PWM driver for SiFive SoC
Adds a PWM driver for PWM chip present in SiFive's HiFive Unleashed SoC
This driver is simple port of Linux pwm sifive driver from Linux v5.6

commit: 9e37a53eb051 ("pwm: sifive: Add a driver for SiFive SoC PWM")

Signed-off-by: Yash Shah <yash.shah@sifive.com>
Reviewed-by: Heiko Schocher <hs@denx.de>
2020-07-09 06:03:12 +02:00
Sam Shih
a537fa4da1 mediatek: pwm: add pwm driver for MediaTek SoCs
This driver support the standard PWM API for
MediaTek MT7623, MT7622 and MT7629 SoCs

Signed-off-by: Sam Shih <sam.shih@mediatek.com>
2020-04-17 12:32:36 -04:00
Heiko Schocher
e0f0657ddf pwm: imx: add Kconfig support
add Kconfig support for this driver.

Signed-off-by: Heiko Schocher <hs@denx.de>
Acked-by: Martyn Welch <martyn.welch@collabora.co.uk>
2019-07-19 20:14:50 +02:00
Vasily Khoruzhick
1c353aea2b pwm: sunxi: add support for PWM found on Allwinner A64
This commit adds basic support for PWM found on Allwinner A64.
It can be used for pwm_backlight driver (e.g. for Pinebook)

Signed-off-by: Vasily Khoruzhick <anarsoul@gmail.com>
2018-05-15 08:18:09 +02:00
Simon Glass
43b41566f7 dm: sandbox: pwm: Add a basic pwm test
Unfortunately a test for the PWM uclass was not included when it was
submitted. This was noticed when trying to add more functionality:

   http://patchwork.ozlabs.org/patch/748172/

Add a simple test to get us started.

Signed-off-by: Simon Glass <sjg@chromium.org>
2017-04-27 16:49:02 -04:00
Simon Glass
5c2dd4cd7a exynos: pwm: Add a driver for the exynos5 PWM
This driver supports the standard PWM API. There are 5 PWMs. Four are used
normally and the last is normally used as a timer.

Signed-off-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Minkyu Kang <mk7.kang@samsung.com>
2016-05-25 13:25:18 +09:00
Simon Glass
91c08afe66 tegra: video: Move LCD driver to use the DM PWM driver
Use the driver-model PWM driver in preference to the old code.

Signed-off-by: Simon Glass <sjg@chromium.org>
Acked-by: Anatolij Gustschin <agust@denx.de>
Signed-off-by: Tom Warren <twarren@nvidia.com>
2016-02-16 09:17:53 -07:00
Simon Glass
41fa035ce1 tegra: Convert CONFIG_PWM_TEGRA to Kconfig
Move this option to Kconfig and clean up the header files. Adjust the only
user (the LCD driver) to work with the new driver.

Signed-off-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Tom Warren <twarren@nvidia.com>
2016-02-16 09:17:53 -07:00
Simon Glass
0e23fd81a5 pwm: rockchip: Add a PWM driver for Rockchip SoCs
Add a simple driver which implements the standard PWM uclass interface.

Signed-off-by: Simon Glass <sjg@chromium.org>
2016-01-21 20:42:36 -07:00
Simon Glass
fc760cb8c4 dm: pwm: Add a PWM uclass
Add a uclass that supports Pulse Width Modulation (PWM) devices. It
provides methods to enable/disable and configure the device.

Signed-off-by: Simon Glass <sjg@chromium.org>
2016-01-21 20:42:36 -07:00