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-rw-r--r--drivers/pwm/Kconfig9
-rw-r--r--drivers/pwm/Makefile1
-rw-r--r--drivers/pwm/cros_ec_pwm.c84
-rw-r--r--drivers/pwm/rk_pwm.c2
-rw-r--r--drivers/pwm/sandbox_pwm.c11
5 files changed, 104 insertions, 3 deletions
diff --git a/drivers/pwm/Kconfig b/drivers/pwm/Kconfig
index ccf81abbe9..cf7f4c6840 100644
--- a/drivers/pwm/Kconfig
+++ b/drivers/pwm/Kconfig
@@ -9,6 +9,15 @@ config DM_PWM
frequency/period can be controlled along with the proportion of that
time that the signal is high.
+config PWM_CROS_EC
+ bool "Enable support for the Chrome OS EC PWM"
+ depends on DM_PWM
+ help
+ This PWM is found on several Chrome OS devices and controlled by
+ the Chrome OS embedded controller. It may be used to control the
+ screen brightness and/or the keyboard backlight depending on the
+ device.
+
config PWM_EXYNOS
bool "Enable support for the Exynos PWM"
depends on DM_PWM
diff --git a/drivers/pwm/Makefile b/drivers/pwm/Makefile
index 0b9d2698a3..10d244bfb7 100644
--- a/drivers/pwm/Makefile
+++ b/drivers/pwm/Makefile
@@ -10,6 +10,7 @@
obj-$(CONFIG_DM_PWM) += pwm-uclass.o
+obj-$(CONFIG_PWM_CROS_EC) += cros_ec_pwm.o
obj-$(CONFIG_PWM_EXYNOS) += exynos_pwm.o
obj-$(CONFIG_PWM_IMX) += pwm-imx.o pwm-imx-util.o
obj-$(CONFIG_PWM_MESON) += pwm-meson.o
diff --git a/drivers/pwm/cros_ec_pwm.c b/drivers/pwm/cros_ec_pwm.c
new file mode 100644
index 0000000000..44f4105dfd
--- /dev/null
+++ b/drivers/pwm/cros_ec_pwm.c
@@ -0,0 +1,84 @@
+// SPDX-License-Identifier: GPL-2.0+
+
+#include <common.h>
+#include <cros_ec.h>
+#include <dm.h>
+#include <errno.h>
+#include <log.h>
+#include <pwm.h>
+
+struct cros_ec_pwm_priv {
+ bool enabled;
+ uint duty;
+};
+
+static int cros_ec_pwm_set_config(struct udevice *dev, uint channel,
+ uint period_ns, uint duty_ns)
+{
+ struct cros_ec_pwm_priv *priv = dev_get_priv(dev);
+ uint duty;
+ int ret;
+
+ debug("%s: period_ns=%u, duty_ns=%u asked\n", __func__,
+ period_ns, duty_ns);
+
+ /* No way to set the period, only a relative duty cycle */
+ duty = EC_PWM_MAX_DUTY * duty_ns / period_ns;
+ if (duty > EC_PWM_MAX_DUTY)
+ duty = EC_PWM_MAX_DUTY;
+
+ if (!priv->enabled) {
+ priv->duty = duty;
+ debug("%s: duty=%#x to-be-set\n", __func__, duty);
+ return 0;
+ }
+
+ ret = cros_ec_set_pwm_duty(dev->parent, channel, duty);
+ if (ret) {
+ debug("%s: duty=%#x failed\n", __func__, duty);
+ return ret;
+ }
+
+ priv->duty = duty;
+ debug("%s: duty=%#x set\n", __func__, duty);
+
+ return 0;
+}
+
+static int cros_ec_pwm_set_enable(struct udevice *dev, uint channel,
+ bool enable)
+{
+ struct cros_ec_pwm_priv *priv = dev_get_priv(dev);
+ int ret;
+
+ ret = cros_ec_set_pwm_duty(dev->parent, channel,
+ enable ? priv->duty : 0);
+ if (ret) {
+ debug("%s: enable=%d failed\n", __func__, enable);
+ return ret;
+ }
+
+ priv->enabled = enable;
+ debug("%s: enable=%d (duty=%#x) set\n", __func__,
+ enable, priv->duty);
+
+ return 0;
+}
+
+static const struct pwm_ops cros_ec_pwm_ops = {
+ .set_config = cros_ec_pwm_set_config,
+ .set_enable = cros_ec_pwm_set_enable,
+};
+
+static const struct udevice_id cros_ec_pwm_ids[] = {
+ { .compatible = "google,cros-ec-pwm" },
+ { }
+};
+
+U_BOOT_DRIVER(cros_ec_pwm) = {
+ .name = "cros_ec_pwm",
+ .id = UCLASS_PWM,
+ .of_match = cros_ec_pwm_ids,
+ .ops = &cros_ec_pwm_ops,
+ .priv_auto_alloc_size = sizeof(struct cros_ec_pwm_priv),
+};
diff --git a/drivers/pwm/rk_pwm.c b/drivers/pwm/rk_pwm.c
index 9cf0980345..071eb04fda 100644
--- a/drivers/pwm/rk_pwm.c
+++ b/drivers/pwm/rk_pwm.c
@@ -147,7 +147,7 @@ static int rk_pwm_probe(struct udevice *dev)
priv->data = (struct rockchip_pwm_data *)dev_get_driver_data(dev);
if (priv->data->supports_polarity)
- priv->conf_polarity = PWM_DUTY_POSTIVE | PWM_INACTIVE_POSTIVE;
+ priv->conf_polarity = PWM_DUTY_POSTIVE | PWM_INACTIVE_NEGATIVE;
return 0;
}
diff --git a/drivers/pwm/sandbox_pwm.c b/drivers/pwm/sandbox_pwm.c
index 318dce7c14..4df15f0a2e 100644
--- a/drivers/pwm/sandbox_pwm.c
+++ b/drivers/pwm/sandbox_pwm.c
@@ -59,8 +59,15 @@ static int sandbox_pwm_set_config(struct udevice *dev, uint channel,
if (channel >= NUM_CHANNELS)
return -ENOSPC;
chan = &priv->chan[channel];
- chan->period_ns = period_ns;
- chan->duty_ns = duty_ns;
+
+ if (channel == 2) {
+ /* Pretend to have some fixed period */
+ chan->period_ns = 4096;
+ chan->duty_ns = duty_ns * 4096 / period_ns;
+ } else {
+ chan->period_ns = period_ns;
+ chan->duty_ns = duty_ns;
+ }
return 0;
}