On Apr 21, 2018, at 10:26 AM, Jonathan Cameron <jic23@kernel.org> wrote:

On Sat, 21 Apr 2018 08:56:19 -0300
Rodrigo Siqueira <rodrigosiqueiramelo@gmail.com> wrote:

This patch adds the ade7854_write_raw() function which is responsible
for handling the write operation for registers: AIGAIN, BIGAIN, CIGAIN,
NIGAIN, AVGAIN, BVGAIN, and CVGAIN. Finally, this patch completely
removes the old ABI used for handling the registers mentioned above.

Signed-off-by: Rodrigo Siqueira <rodrigosiqueiramelo@gmail.com>

The baby steps approach here is good, but with all 3 patches as one it
would have been a lot easier to follow.

This is almost fine except for the issue I had with how the channels
were defined in the first place.

Also a question about scales inline...

---
drivers/staging/iio/meter/ade7854.c | 60 ++++++++++++-----------------
1 file changed, 25 insertions(+), 35 deletions(-)

diff --git a/drivers/staging/iio/meter/ade7854.c b/drivers/staging/iio/meter/ade7854.c
index 242ecde75900..df19c8b4b5d7 100644
--- a/drivers/staging/iio/meter/ade7854.c
+++ b/drivers/staging/iio/meter/ade7854.c
@@ -228,34 +228,6 @@ static int ade7854_reset(struct device *dev)
return st->write_reg(dev, ADE7854_CONFIG, val, 16);
}

-static IIO_DEV_ATTR_AIGAIN(0644,
- NULL,
- ade7854_write_24bit,
- ADE7854_AIGAIN);
-static IIO_DEV_ATTR_BIGAIN(0644,
- NULL,
- ade7854_write_24bit,
- ADE7854_BIGAIN);
-static IIO_DEV_ATTR_CIGAIN(0644,
- NULL,
- ade7854_write_24bit,
- ADE7854_CIGAIN);
-static IIO_DEV_ATTR_NIGAIN(0644,
- NULL,
- ade7854_write_24bit,
- ADE7854_NIGAIN);
-static IIO_DEV_ATTR_AVGAIN(0644,
- NULL,
- ade7854_write_24bit,
- ADE7854_AVGAIN);
-static IIO_DEV_ATTR_BVGAIN(0644,
- NULL,
- ade7854_write_24bit,
- ADE7854_BVGAIN);
-static IIO_DEV_ATTR_CVGAIN(0644,
- NULL,
- ade7854_write_24bit,
- ADE7854_CVGAIN);
static IIO_DEV_ATTR_APPARENT_POWER_A_GAIN(0644,
ade7854_read_24bit,
ade7854_write_24bit,
@@ -497,6 +469,30 @@ static int ade7854_read_raw(struct iio_dev *indio_dev,
return -EINVAL;
}

+static int ade7854_write_raw(struct iio_dev *indio_dev,
+      struct iio_chan_spec const *chan,
+      int val, int val2, long mask)
+{
+ struct ade7854_state *st = iio_priv(indio_dev);
+ int ret;
+
+ if (mask != IIO_CHAN_INFO_SCALE)
+ return -EINVAL;
+
+ switch (chan->type) {
+ case IIO_CURRENT:
+ case IIO_VOLTAGE:

Probably need some range checking to make sure we have a sane value.

Also, I'm curious about units here.

you are using CHAN_INFO_SCALE which would mean this is linked to
the _RAW value (the actual reading of the channel) by _RAW*_SCALE = value in
defined base units for the channel type.  So I'd expect to see some
code here doing a conversion to the internal format for the device.

I wouldn't expect to see a value from userspace written unconverted
into the register.

(I missed this in the previous patch - sorry).

Jonathan

+ ret = st->write_reg(&indio_dev->dev, chan->address, val, 24);
+ if (ret < 0)
+ return ret;
+ return 0;
+ default:
+ break;
+ }
+
+ return -EINVAL;
+}
+
static int ade7854_initial_setup(struct iio_dev *indio_dev)
{
int ret;
@@ -521,13 +517,6 @@ static IIO_CONST_ATTR_SAMP_FREQ_AVAIL("8000");
static IIO_CONST_ATTR(name, "ade7854");

static struct attribute *ade7854_attributes[] = {
- &iio_dev_attr_aigain.dev_attr.attr,
- &iio_dev_attr_bigain.dev_attr.attr,
- &iio_dev_attr_cigain.dev_attr.attr,
- &iio_dev_attr_nigain.dev_attr.attr,
- &iio_dev_attr_avgain.dev_attr.attr,
- &iio_dev_attr_bvgain.dev_attr.attr,
- &iio_dev_attr_cvgain.dev_attr.attr,
&iio_dev_attr_linecyc.dev_attr.attr,
&iio_dev_attr_sagcyc.dev_attr.attr,
&iio_dev_attr_cfcyc.dev_attr.attr,
@@ -599,6 +588,7 @@ static const struct attribute_group ade7854_attribute_group = {
static const struct iio_info ade7854_info = {
.attrs = &ade7854_attribute_group,
.read_raw = &ade7854_read_raw,
+ .write_raw = &ade7854_write_raw,
};

int ade7854_probe(struct iio_dev *indio_dev, struct device *dev)