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path: root/drivers/iio/proximity/srf04.c
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Diffstat (limited to 'drivers/iio/proximity/srf04.c')
-rw-r--r--drivers/iio/proximity/srf04.c96
1 files changed, 95 insertions, 1 deletions
diff --git a/drivers/iio/proximity/srf04.c b/drivers/iio/proximity/srf04.c
index 01eb8cc63076..568b76e06385 100644
--- a/drivers/iio/proximity/srf04.c
+++ b/drivers/iio/proximity/srf04.c
@@ -45,6 +45,7 @@
#include <linux/sched.h>
#include <linux/interrupt.h>
#include <linux/delay.h>
+#include <linux/pm_runtime.h>
#include <linux/iio/iio.h>
#include <linux/iio/sysfs.h>
@@ -56,6 +57,7 @@ struct srf04_data {
struct device *dev;
struct gpio_desc *gpiod_trig;
struct gpio_desc *gpiod_echo;
+ struct gpio_desc *gpiod_power;
struct mutex lock;
int irqnr;
ktime_t ts_rising;
@@ -63,6 +65,7 @@ struct srf04_data {
struct completion rising;
struct completion falling;
const struct srf04_cfg *cfg;
+ int startup_time_ms;
};
static const struct srf04_cfg srf04_cfg = {
@@ -97,6 +100,9 @@ static int srf04_read(struct srf04_data *data)
u64 dt_ns;
u32 time_ns, distance_mm;
+ if (data->gpiod_power)
+ pm_runtime_get_sync(data->dev);
+
/*
* just one read-echo-cycle can take place at a time
* ==> lock against concurrent reading calls
@@ -110,6 +116,11 @@ static int srf04_read(struct srf04_data *data)
udelay(data->cfg->trigger_pulse_us);
gpiod_set_value(data->gpiod_trig, 0);
+ if (data->gpiod_power) {
+ pm_runtime_mark_last_busy(data->dev);
+ pm_runtime_put_autosuspend(data->dev);
+ }
+
/* it should not take more than 20 ms until echo is rising */
ret = wait_for_completion_killable_timeout(&data->rising, HZ/50);
if (ret < 0) {
@@ -268,6 +279,22 @@ static int srf04_probe(struct platform_device *pdev)
return PTR_ERR(data->gpiod_echo);
}
+ data->gpiod_power = devm_gpiod_get_optional(dev, "power",
+ GPIOD_OUT_LOW);
+ if (IS_ERR(data->gpiod_power)) {
+ dev_err(dev, "failed to get power-gpios: err=%ld\n",
+ PTR_ERR(data->gpiod_power));
+ return PTR_ERR(data->gpiod_power);
+ }
+ if (data->gpiod_power) {
+
+ if (of_property_read_u32(dev->of_node, "startup-time-ms",
+ &data->startup_time_ms))
+ data->startup_time_ms = 100;
+ dev_dbg(dev, "using power gpio: startup-time-ms=%d\n",
+ data->startup_time_ms);
+ }
+
if (gpiod_cansleep(data->gpiod_echo)) {
dev_err(data->dev, "cansleep-GPIOs not supported\n");
return -ENODEV;
@@ -296,14 +323,81 @@ static int srf04_probe(struct platform_device *pdev)
indio_dev->channels = srf04_chan_spec;
indio_dev->num_channels = ARRAY_SIZE(srf04_chan_spec);
- return devm_iio_device_register(dev, indio_dev);
+ ret = iio_device_register(indio_dev);
+ if (ret < 0) {
+ dev_err(data->dev, "iio_device_register: %d\n", ret);
+ return ret;
+ }
+
+ if (data->gpiod_power) {
+ pm_runtime_set_autosuspend_delay(data->dev, 1000);
+ pm_runtime_use_autosuspend(data->dev);
+
+ ret = pm_runtime_set_active(data->dev);
+ if (ret) {
+ dev_err(data->dev, "pm_runtime_set_active: %d\n", ret);
+ iio_device_unregister(indio_dev);
+ }
+
+ pm_runtime_enable(data->dev);
+ pm_runtime_idle(data->dev);
+ }
+
+ return ret;
}
+static int srf04_remove(struct platform_device *pdev)
+{
+ struct iio_dev *indio_dev = platform_get_drvdata(pdev);
+ struct srf04_data *data = iio_priv(indio_dev);
+
+ iio_device_unregister(indio_dev);
+
+ if (data->gpiod_power) {
+ pm_runtime_disable(data->dev);
+ pm_runtime_set_suspended(data->dev);
+ }
+
+ return 0;
+}
+
+static int __maybe_unused srf04_pm_runtime_suspend(struct device *dev)
+{
+ struct platform_device *pdev = container_of(dev,
+ struct platform_device, dev);
+ struct iio_dev *indio_dev = platform_get_drvdata(pdev);
+ struct srf04_data *data = iio_priv(indio_dev);
+
+ gpiod_set_value(data->gpiod_power, 0);
+
+ return 0;
+}
+
+static int __maybe_unused srf04_pm_runtime_resume(struct device *dev)
+{
+ struct platform_device *pdev = container_of(dev,
+ struct platform_device, dev);
+ struct iio_dev *indio_dev = platform_get_drvdata(pdev);
+ struct srf04_data *data = iio_priv(indio_dev);
+
+ gpiod_set_value(data->gpiod_power, 1);
+ msleep(data->startup_time_ms);
+
+ return 0;
+}
+
+static const struct dev_pm_ops srf04_pm_ops = {
+ SET_RUNTIME_PM_OPS(srf04_pm_runtime_suspend,
+ srf04_pm_runtime_resume, NULL)
+};
+
static struct platform_driver srf04_driver = {
.probe = srf04_probe,
+ .remove = srf04_remove,
.driver = {
.name = "srf04-gpio",
.of_match_table = of_srf04_match,
+ .pm = &srf04_pm_ops,
},
};