iio: cros_ec: Reapply range at resume

EC does not currently preserve range across sensor reinit.
If sensor is powered down at suspend, it will default to the EC default
range at resume, not the range set by the host.

Save range if modified, and apply at resume.

Signed-off-by: Gwendal Grignou <gwendal@chromium.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

4 files changed, 37 insertions, 3 deletions

diff --git a/drivers/iio/common/cros_ec_sensors/cros_ec_sensors.c b/drivers/iio/common/cros_ec_sensors/cros_ec_sensors.c
index a66941fdb385..130ab8ce0269 100644
--- a/drivers/iio/common/cros_ec_sensors/cros_ec_sensors.c
+++ b/drivers/iio/common/cros_ec_sensors/cros_ec_sensors.c
@@ -200,6 +200,10 @@ static int cros_ec_sensors_write(struct iio_dev *indio_dev,
 		st->core.param.sensor_range.roundup = 1;
 
 		ret = cros_ec_motion_send_host_cmd(&st->core, 0);
+		if (ret == 0) {
+			st->core.range_updated = true;
+			st->core.curr_range = val;
+		}
 		break;
 	default:
 		ret = cros_ec_sensors_core_write(
@@ -315,6 +319,7 @@ MODULE_DEVICE_TABLE(platform, cros_ec_sensors_ids);
 static struct platform_driver cros_ec_sensors_platform_driver = {
 	.driver = {
 		.name	= "cros-ec-sensors",
+		.pm	= &cros_ec_sensors_pm_ops,
 	},
 	.probe		= cros_ec_sensors_probe,
 	.id_table	= cros_ec_sensors_ids,
diff --git a/drivers/iio/common/cros_ec_sensors/cros_ec_sensors_core.c b/drivers/iio/common/cros_ec_sensors/cros_ec_sensors_core.c
index c831915ca7e5..cda459b61206 100644
--- a/drivers/iio/common/cros_ec_sensors/cros_ec_sensors_core.c
+++ b/drivers/iio/common/cros_ec_sensors/cros_ec_sensors_core.c
@@ -824,5 +824,26 @@ int cros_ec_sensors_core_write(struct cros_ec_sensors_core_state *st,
 }
 EXPORT_SYMBOL_GPL(cros_ec_sensors_core_write);
 
+static int __maybe_unused cros_ec_sensors_resume(struct device *dev)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+	struct iio_dev *indio_dev = platform_get_drvdata(pdev);
+	struct cros_ec_sensors_core_state *st = iio_priv(indio_dev);
+	int ret = 0;
+
+	if (st->range_updated) {
+		mutex_lock(&st->cmd_lock);
+		st->param.cmd = MOTIONSENSE_CMD_SENSOR_RANGE;
+		st->param.sensor_range.data = st->curr_range;
+		st->param.sensor_range.roundup = 1;
+		ret = cros_ec_motion_send_host_cmd(st, 0);
+		mutex_unlock(&st->cmd_lock);
+	}
+	return ret;
+}
+
+SIMPLE_DEV_PM_OPS(cros_ec_sensors_pm_ops, NULL, cros_ec_sensors_resume);
+EXPORT_SYMBOL_GPL(cros_ec_sensors_pm_ops);
+
 MODULE_DESCRIPTION("ChromeOS EC sensor hub core functions");
 MODULE_LICENSE("GPL v2");
diff --git a/drivers/iio/light/cros_ec_light_prox.c b/drivers/iio/light/cros_ec_light_prox.c
index 2198b50909ed..fed79ba27fda 100644
--- a/drivers/iio/light/cros_ec_light_prox.c
+++ b/drivers/iio/light/cros_ec_light_prox.c
@@ -145,8 +145,11 @@ static int cros_ec_light_prox_write(struct iio_dev *indio_dev,
 		break;
 	case IIO_CHAN_INFO_CALIBSCALE:
 		st->core.param.cmd = MOTIONSENSE_CMD_SENSOR_RANGE;
-		st->core.param.sensor_range.data = (val << 16) | (val2 / 100);
+		st->core.curr_range = (val << 16) | (val2 / 100);
+		st->core.param.sensor_range.data = st->core.curr_range;
 		ret = cros_ec_motion_send_host_cmd(&st->core, 0);
+		if (ret == 0)
+			st->core.range_updated = true;
 		break;
 	default:
 		ret = cros_ec_sensors_core_write(&st->core, chan, val, val2,
@@ -256,6 +259,7 @@ MODULE_DEVICE_TABLE(platform, cros_ec_light_prox_ids);
 static struct platform_driver cros_ec_light_prox_platform_driver = {
 	.driver = {
 		.name	= "cros-ec-light-prox",
+		.pm	= &cros_ec_sensors_pm_ops,
 	},
 	.probe		= cros_ec_light_prox_probe,
 	.id_table	= cros_ec_light_prox_ids,
diff --git a/drivers/iio/pressure/cros_ec_baro.c b/drivers/iio/pressure/cros_ec_baro.c
index c079b8960082..f0938b6fbba0 100644
--- a/drivers/iio/pressure/cros_ec_baro.c
+++ b/drivers/iio/pressure/cros_ec_baro.c
@@ -96,8 +96,11 @@ static int cros_ec_baro_write(struct iio_dev *indio_dev,
 		/* Always roundup, so caller gets at least what it asks for. */
 		st->core.param.sensor_range.roundup = 1;
 
-		if (cros_ec_motion_send_host_cmd(&st->core, 0))
-			ret = -EIO;
+		ret = cros_ec_motion_send_host_cmd(&st->core, 0);
+		if (ret == 0) {
+			st->core.range_updated = true;
+			st->core.curr_range = val;
+		}
 		break;
 	default:
 		ret = cros_ec_sensors_core_write(&st->core, chan, val, val2,
@@ -199,6 +202,7 @@ MODULE_DEVICE_TABLE(platform, cros_ec_baro_ids);
 static struct platform_driver cros_ec_baro_platform_driver = {
 	.driver = {
 		.name	= "cros-ec-baro",
+		.pm	= &cros_ec_sensors_pm_ops,
 	},
 	.probe		= cros_ec_baro_probe,
 	.id_table	= cros_ec_baro_ids,