diff options
Diffstat (limited to 'drivers/iio/proximity/srf04.c')
-rw-r--r-- | drivers/iio/proximity/srf04.c | 96 |
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, }, }; |