This is a note to let you know that I've just added the patch titled

iio: magnetometer: ak8974: Fix runtime PM imbalance on error

to my staging git tree which can be found at git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging.git in the staging-linus branch.

The patch will show up in the next release of the linux-next tree (usually sometime within the next 24 hours during the week.)

The patch will hopefully also be merged in Linus's tree for the next -rc kernel release.

If you have any questions about this process, please let me know.

From 0187294d227dfc42889e1da8f8ce1e44fc25f147 Mon Sep 17 00:00:00 2001

From: Dinghao Liu dinghao.liu@zju.edu.cn Date: Tue, 26 May 2020 18:47:17 +0800 Subject: iio: magnetometer: ak8974: Fix runtime PM imbalance on error

When devm_regmap_init_i2c() returns an error code, a pairing runtime PM usage counter decrement is needed to keep the counter balanced. For error paths after ak8974_set_power(), ak8974_detect() and ak8974_reset(), things are the same.

However, When iio_triggered_buffer_setup() returns an error code, there will be two PM usgae counter decrements.

Signed-off-by: Dinghao Liu dinghao.liu@zju.edu.cn Fixes: 7c94a8b2ee8c ("iio: magn: add a driver for AK8974") Reviewed-by: Linus Walleij linus.walleij@linaro.org Cc: Stable@vger.kernel.org Signed-off-by: Jonathan Cameron Jonathan.Cameron@huawei.com --- drivers/iio/magnetometer/ak8974.c | 19 ++++++++++--------- 1 file changed, 10 insertions(+), 9 deletions(-)

diff --git a/drivers/iio/magnetometer/ak8974.c b/drivers/iio/magnetometer/ak8974.c index 810fdfd37c88..041c9007bfbe 100644 --- a/drivers/iio/magnetometer/ak8974.c +++ b/drivers/iio/magnetometer/ak8974.c @@ -862,19 +862,21 @@ static int ak8974_probe(struct i2c_client *i2c, ak8974->map = devm_regmap_init_i2c(i2c, &ak8974_regmap_config); if (IS_ERR(ak8974->map)) { dev_err(&i2c->dev, "failed to allocate register map\n"); + pm_runtime_put_noidle(&i2c->dev); + pm_runtime_disable(&i2c->dev); return PTR_ERR(ak8974->map); }

ret = ak8974_set_power(ak8974, AK8974_PWR_ON); if (ret) { dev_err(&i2c->dev, "could not power on\n"); - goto power_off; + goto disable_pm; }

ret = ak8974_detect(ak8974); if (ret) { dev_err(&i2c->dev, "neither AK8974 nor AMI30x found\n"); - goto power_off; + goto disable_pm; }

ret = ak8974_selftest(ak8974); @@ -884,14 +886,9 @@ static int ak8974_probe(struct i2c_client *i2c, ret = ak8974_reset(ak8974); if (ret) { dev_err(&i2c->dev, "AK8974 reset failed\n"); - goto power_off; + goto disable_pm; }

- pm_runtime_set_autosuspend_delay(&i2c->dev, - AK8974_AUTOSUSPEND_DELAY); - pm_runtime_use_autosuspend(&i2c->dev); - pm_runtime_put(&i2c->dev); - indio_dev->dev.parent = &i2c->dev; switch (ak8974->variant) { case AK8974_WHOAMI_VALUE_AMI306: @@ -957,6 +954,11 @@ static int ak8974_probe(struct i2c_client *i2c, goto cleanup_buffer; }

+ pm_runtime_set_autosuspend_delay(&i2c->dev, + AK8974_AUTOSUSPEND_DELAY); + pm_runtime_use_autosuspend(&i2c->dev); + pm_runtime_put(&i2c->dev); + return 0;

cleanup_buffer: @@ -965,7 +967,6 @@ static int ak8974_probe(struct i2c_client *i2c, pm_runtime_put_noidle(&i2c->dev); pm_runtime_disable(&i2c->dev); ak8974_set_power(ak8974, AK8974_PWR_OFF); -power_off: regulator_bulk_disable(ARRAY_SIZE(ak8974->regs), ak8974->regs);

return ret;