iio: health: max30102: Add power enable parameter to get_temp function

Chip must not be in shutdown for reading temperature, so briefly leave
shutdown if buffer is not already running

Signed-off-by: Peter Meerwald-Stadler <pmeerw@pmeerw.net>
Acked-by: Matt Ranostay <matt.ranostay@konsulko.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

diff --git a/drivers/iio/health/max30102.c b/drivers/iio/health/max30102.c
index 6c395c8..dc4d04b 100644 (file)
--- a/drivers/iio/health/max30102.c
+++ b/drivers/iio/health/max30102.c
@@ -321,20 +321,31 @@ static int max30102_read_temp(struct max30102_data *data, int *val)
        return 0;
 }
 
-static int max30102_get_temp(struct max30102_data *data, int *val)
+static int max30102_get_temp(struct max30102_data *data, int *val, bool en)
 {
        int ret;
 
+       if (en) {
+               ret = max30102_set_powermode(data, true);
+               if (ret)
+                       return ret;
+       }
+
        /* start acquisition */
        ret = regmap_update_bits(data->regmap, MAX30102_REG_TEMP_CONFIG,
                                 MAX30102_REG_TEMP_CONFIG_TEMP_EN,
                                 MAX30102_REG_TEMP_CONFIG_TEMP_EN);
        if (ret)
-               return ret;
+               goto out;
 
        msleep(35);
+       ret = max30102_read_temp(data, val);
+
+out:
+       if (en)
+               max30102_set_powermode(data, false);
 
-       return max30102_read_temp(data, val);
+       return ret;
 }
 
 static int max30102_read_raw(struct iio_dev *indio_dev,
@@ -347,20 +358,19 @@ static int max30102_read_raw(struct iio_dev *indio_dev,
        switch (mask) {
        case IIO_CHAN_INFO_RAW:
                /*
-                * Temperature reading can only be acquired while engine
-                * is running
+                * Temperature reading can only be acquired when not in
+                * shutdown; leave shutdown briefly when buffer not running
                 */
                mutex_lock(&indio_dev->mlock);
-
                if (!iio_buffer_enabled(indio_dev))
-                       ret = -EBUSY;
-               else {
-                       ret = max30102_get_temp(data, val);
-                       if (!ret)
-                               ret = IIO_VAL_INT;
-               }
-
+                       ret = max30102_get_temp(data, val, true);
+               else
+                       ret = max30102_get_temp(data, val, false);
                mutex_unlock(&indio_dev->mlock);
+               if (ret)
+                       return ret;
+
+               ret = IIO_VAL_INT;
                break;
        case IIO_CHAN_INFO_SCALE:
                *val = 1;  /* 0.0625 */