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authorSimon Glass <sjg@chromium.org>2016-01-21 19:44:54 -0700
committerSimon Glass <sjg@chromium.org>2016-01-21 20:42:36 -0700
commitfc760cb8c4cc16061079fb45e2e0bad11e5acedc (patch)
treed796c4f0ae64c7d5d32b26f4fdcd9a145be5f52f
parentd4bf91ada110aeb26f844cbe95cdb9b1ddb87f19 (diff)
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>
-rw-r--r--drivers/Kconfig2
-rw-r--r--drivers/pwm/Kconfig10
-rw-r--r--drivers/pwm/Makefile1
-rw-r--r--drivers/pwm/pwm-uclass.c36
-rw-r--r--include/dm/uclass-id.h1
-rw-r--r--include/pwm.h53
6 files changed, 103 insertions, 0 deletions
diff --git a/drivers/Kconfig b/drivers/Kconfig
index c481e93356d..70993fdab80 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 00000000000..bd471598602
--- /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 c0c48833173..d1b15e5b11e 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 00000000000..c2200af8a55
--- /dev/null
+++ b/drivers/pwm/pwm-uclass.c
@@ -0,0 +1,36 @@
+/*
+ * Copyright (c) 2016 Google, Inc
+ * Written by Simon Glass <sjg@chromium.org>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#include <common.h>
+#include <dm.h>
+#include <pwm.h>
+
+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 b5f43ae95e6..8f0381d6e55 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 f24f2202f48..851915eb87a 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 <dh09.lee@samsung.com>
*
@@ -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_ */