From fc760cb8c4cc16061079fb45e2e0bad11e5acedc Mon Sep 17 00:00:00 2001 From: Simon Glass Date: Thu, 21 Jan 2016 19:44:54 -0700 Subject: [PATCH] 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 --- drivers/Kconfig | 2 ++ drivers/pwm/Kconfig | 10 ++++++++ drivers/pwm/Makefile | 1 + drivers/pwm/pwm-uclass.c | 36 +++++++++++++++++++++++++++ include/dm/uclass-id.h | 1 + include/pwm.h | 53 ++++++++++++++++++++++++++++++++++++++++ 6 files changed, 103 insertions(+) create mode 100644 drivers/pwm/Kconfig create mode 100644 drivers/pwm/pwm-uclass.c diff --git a/drivers/Kconfig b/drivers/Kconfig index c481e93356..70993fdab8 100644 --- a/drivers/Kconfig +++ b/drivers/Kconfig @@ -46,6 +46,8 @@ source "drivers/pinctrl/Kconfig" source "drivers/power/Kconfig" +source "drivers/pwm/Kconfig" + source "drivers/ram/Kconfig" source "drivers/remoteproc/Kconfig" diff --git a/drivers/pwm/Kconfig b/drivers/pwm/Kconfig new file mode 100644 index 0000000000..bd47159860 --- /dev/null +++ b/drivers/pwm/Kconfig @@ -0,0 +1,10 @@ +config DM_PWM + bool "Enable support for pulse-width modulation devices (PWM)" + depends on DM + help + A pulse-width modulator emits a pulse of varying width and provides + control over the duty cycle (high and low time) of the signal. This + is often used to control a voltage level. The more time the PWM + spends in the 'high' state, the higher the voltage. The PWM's + frequency/period can be controlled along with the proportion of that + time that the signal is high. diff --git a/drivers/pwm/Makefile b/drivers/pwm/Makefile index c0c4883317..d1b15e5b11 100644 --- a/drivers/pwm/Makefile +++ b/drivers/pwm/Makefile @@ -10,4 +10,5 @@ #ccflags-y += -DDEBUG +obj-$(CONFIG_DM_PWM) += pwm-uclass.o obj-$(CONFIG_PWM_IMX) += pwm-imx.o pwm-imx-util.o diff --git a/drivers/pwm/pwm-uclass.c b/drivers/pwm/pwm-uclass.c new file mode 100644 index 0000000000..c2200af8a5 --- /dev/null +++ b/drivers/pwm/pwm-uclass.c @@ -0,0 +1,36 @@ +/* + * Copyright (c) 2016 Google, Inc + * Written by Simon Glass + * + * SPDX-License-Identifier: GPL-2.0+ + */ + +#include +#include +#include + +int pwm_set_config(struct udevice *dev, uint channel, uint period_ns, + uint duty_ns) +{ + struct pwm_ops *ops = pwm_get_ops(dev); + + if (!ops->set_config) + return -ENOSYS; + + return ops->set_config(dev, channel, period_ns, duty_ns); +} + +int pwm_set_enable(struct udevice *dev, uint channel, bool enable) +{ + struct pwm_ops *ops = pwm_get_ops(dev); + + if (!ops->set_enable) + return -ENOSYS; + + return ops->set_enable(dev, channel, enable); +} + +UCLASS_DRIVER(pwm) = { + .id = UCLASS_PWM, + .name = "pwm", +}; diff --git a/include/dm/uclass-id.h b/include/dm/uclass-id.h index b5f43ae95e..8f0381d6e5 100644 --- a/include/dm/uclass-id.h +++ b/include/dm/uclass-id.h @@ -51,6 +51,7 @@ enum uclass_id { UCLASS_PINCTRL, /* Pinctrl (pin muxing/configuration) device */ UCLASS_PINCONFIG, /* Pin configuration node device */ UCLASS_PMIC, /* PMIC I/O device */ + UCLASS_PWM, /* Pulse-width modulator */ UCLASS_PWRSEQ, /* Power sequence device */ UCLASS_REGULATOR, /* Regulator device */ UCLASS_RESET, /* Reset device */ diff --git a/include/pwm.h b/include/pwm.h index f24f2202f4..851915eb87 100644 --- a/include/pwm.h +++ b/include/pwm.h @@ -1,6 +1,7 @@ /* * header file for pwm driver. * + * Copyright 2016 Google Inc. * Copyright (c) 2011 samsung electronics * Donghwa Lee * @@ -10,9 +11,61 @@ #ifndef _pwm_h_ #define _pwm_h_ +/* struct pwm_ops: Operations for the PWM uclass */ +struct pwm_ops { + /** + * set_config() - Set the PWM configuration + * + * @dev: PWM device to update + * @channel: PWM channel to update + * @period_ns: PWM period in nanoseconds + * @duty_ns: PWM duty period in nanoseconds + * @return 0 if OK, -ve on error + */ + int (*set_config)(struct udevice *dev, uint channel, uint period_ns, + uint duty_ns); + + /** + * set_enable() - Enable or disable the PWM + * + * @dev: PWM device to update + * @channel: PWM channel to update + * @enable: true to enable, false to disable + * @return 0 if OK, -ve on error + */ + int (*set_enable)(struct udevice *dev, uint channel, bool enable); +}; + +#define pwm_get_ops(dev) ((struct pwm_ops *)(dev)->driver->ops) + +/** + * pwm_set_config() - Set the PWM configuration + * + * @dev: PWM device to update + * @channel: PWM channel to update + * @period_ns: PWM period in nanoseconds + * @duty_ns: PWM duty period in nanoseconds + * @return 0 if OK, -ve on error + */ +int pwm_set_config(struct udevice *dev, uint channel, uint period_ns, + uint duty_ns); + +/** + * pwm_set_enable() - Enable or disable the PWM + * + * @dev: PWM device to update + * @channel: PWM channel to update + * @enable: true to enable, false to disable + * @return 0 if OK, -ve on error + */ +int pwm_set_enable(struct udevice *dev, uint channel, bool enable); + +/* Legacy interface */ +#ifndef CONFIG_DM_PWM int pwm_init (int pwm_id, int div, int invert); int pwm_config (int pwm_id, int duty_ns, int period_ns); int pwm_enable (int pwm_id); void pwm_disable (int pwm_id); +#endif #endif /* _pwm_h_ */