iio: magn: bmc150: Balance runtime pm + use pm_runtime_resume_and_get()

probe() error paths after runtime pm is enabled, should disable it.
remove() should not call pm_runtime_put_noidle() as there is no
matching get() to have raised the reference count.  This case
has no affect a the runtime pm core protects against going negative.

Whilst here use pm_runtime_resume_and_get() to tidy things up a little.
coccicheck script didn't get this one due to complex code structure so
found by inspection.

Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Cc: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Link: https://lore.kernel.org/r/20210509113354.660190-12-jic23@kernel.org

diff --git a/drivers/iio/magnetometer/bmc150_magn.c b/drivers/iio/magnetometer/bmc150_magn.c
index d75b437..39920cb 100644 (file)
--- a/drivers/iio/magnetometer/bmc150_magn.c
+++ b/drivers/iio/magnetometer/bmc150_magn.c
@@ -262,7 +262,7 @@ static int bmc150_magn_set_power_state(struct bmc150_magn_data *data, bool on)
        int ret;
 
        if (on) {
-               ret = pm_runtime_get_sync(data->dev);
+               ret = pm_runtime_resume_and_get(data->dev);
        } else {
                pm_runtime_mark_last_busy(data->dev);
                ret = pm_runtime_put_autosuspend(data->dev);
@@ -271,9 +271,6 @@ static int bmc150_magn_set_power_state(struct bmc150_magn_data *data, bool on)
        if (ret < 0) {
                dev_err(data->dev,
                        "failed to change power state to %d\n", on);
-               if (on)
-                       pm_runtime_put_noidle(data->dev);
-
                return ret;
        }
 #endif
@@ -963,12 +960,14 @@ int bmc150_magn_probe(struct device *dev, struct regmap *regmap,
        ret = iio_device_register(indio_dev);
        if (ret < 0) {
                dev_err(dev, "unable to register iio device\n");
-               goto err_buffer_cleanup;
+               goto err_disable_runtime_pm;
        }
 
        dev_dbg(dev, "Registered device %s\n", name);
        return 0;
 
+err_disable_runtime_pm:
+       pm_runtime_disable(dev);
 err_buffer_cleanup:
        iio_triggered_buffer_cleanup(indio_dev);
 err_free_irq:
@@ -992,7 +991,6 @@ int bmc150_magn_remove(struct device *dev)
 
        pm_runtime_disable(dev);
        pm_runtime_set_suspended(dev);
-       pm_runtime_put_noidle(dev);
 
        iio_triggered_buffer_cleanup(indio_dev);