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

iio: ad5064: Fix regulator handling

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-testing 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 be merged to the staging-next branch sometime soon, after it passes testing, and the merge window is open.

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

From 8911a43bc198877fad9f4b0246a866b26bb547ab Mon Sep 17 00:00:00 2001

From: Lars-Peter Clausen lars@metafoo.de Date: Fri, 28 Sep 2018 11:23:40 +0200 Subject: iio: ad5064: Fix regulator handling

The correct way to handle errors returned by regualtor_get() and friends is to propagate the error since that means that an regulator was specified, but something went wrong when requesting it.

For handling optional regulators, e.g. when the device has an internal vref, regulator_get_optional() should be used to avoid getting the dummy regulator that the regulator core otherwise provides.

Signed-off-by: Lars-Peter Clausen lars@metafoo.de Cc: Stable@vger.kernel.org Signed-off-by: Jonathan Cameron Jonathan.Cameron@huawei.com --- drivers/iio/dac/ad5064.c | 53 ++++++++++++++++++++++++++++------------ 1 file changed, 38 insertions(+), 15 deletions(-)

diff --git a/drivers/iio/dac/ad5064.c b/drivers/iio/dac/ad5064.c index bf4fc40ec84d..2f98cb2a3b96 100644 --- a/drivers/iio/dac/ad5064.c +++ b/drivers/iio/dac/ad5064.c @@ -808,6 +808,40 @@ static int ad5064_set_config(struct ad5064_state *st, unsigned int val) return ad5064_write(st, cmd, 0, val, 0); }

+static int ad5064_request_vref(struct ad5064_state *st, struct device *dev) +{ + unsigned int i; + int ret; + + for (i = 0; i < ad5064_num_vref(st); ++i) + st->vref_reg[i].supply = ad5064_vref_name(st, i); + + if (!st->chip_info->internal_vref) + return devm_regulator_bulk_get(dev, ad5064_num_vref(st), + st->vref_reg); + + /* + * This assumes that when the regulator has an internal VREF + * there is only one external VREF connection, which is + * currently the case for all supported devices. + */ + st->vref_reg[0].consumer = devm_regulator_get_optional(dev, "vref"); + if (!IS_ERR(st->vref_reg[0].consumer)) + return 0; + + ret = PTR_ERR(st->vref_reg[0].consumer); + if (ret != -ENODEV) + return ret; + + /* If no external regulator was supplied use the internal VREF */ + st->use_internal_vref = true; + ret = ad5064_set_config(st, AD5064_CONFIG_INT_VREF_ENABLE); + if (ret) + dev_err(dev, "Failed to enable internal vref: %d\n", ret); + + return ret; +} + static int ad5064_probe(struct device *dev, enum ad5064_type type, const char *name, ad5064_write_func write) { @@ -828,22 +862,11 @@ static int ad5064_probe(struct device *dev, enum ad5064_type type, st->dev = dev; st->write = write;

- for (i = 0; i < ad5064_num_vref(st); ++i) - st->vref_reg[i].supply = ad5064_vref_name(st, i); + ret = ad5064_request_vref(st, dev); + if (ret) + return ret;

- ret = devm_regulator_bulk_get(dev, ad5064_num_vref(st), - st->vref_reg); - if (ret) { - if (!st->chip_info->internal_vref) - return ret; - st->use_internal_vref = true; - ret = ad5064_set_config(st, AD5064_CONFIG_INT_VREF_ENABLE); - if (ret) { - dev_err(dev, "Failed to enable internal vref: %d\n", - ret); - return ret; - } - } else { + if (!st->use_internal_vref) { ret = regulator_bulk_enable(ad5064_num_vref(st), st->vref_reg); if (ret) return ret;