Met vriendelijke groet / kind regards,
Mike Looijmans
System Expert
TOPIC Embedded Products B.V.
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On 04-03-2023 18:57, Jonathan Cameron wrote:
On Tue, 28 Feb 2023 07:31:51 +0100
Mike Looijmans <mike.looijmans@xxxxxxxx> wrote:
The ADS1100 is a 16-bit ADC (at 8 samples per second).
The ADS1000 is similar, but has a fixed data rate.
Signed-off-by: Mike Looijmans <mike.looijmans@xxxxxxxx>
Hi Mike,
A few minor things + one request for a test as trying to chase a possible
ref count overflow around the runtime_pm was giving me a enough of a headache
that it's easier to ask you just to poke it and see. If it doesn't fail as
I expect I'll take a closer look!
Will do, but it may take a few days to get access to the hardware again.
I'll report on that later.
+static int ads1100_set_scale(struct ads1100_data *data, int val, int val2)
+{
+ int microvolts;
+ int gain;
+ int i;
+
+ /* With Vdd between 2.7 and 5V, the scale is always below 1 */
+ if (val)
+ return -EINVAL;
+
+ microvolts = regulator_get_voltage(data->reg_vdd);
+ /* Calculate: gain = ((microvolts / 1000) / (val2 / 1000000)) >> 15 */
+ gain = ((microvolts + BIT(14)) >> 15) * 1000 / val2;
+
+ for (i = 0; i < 4; i++) {
+ if (BIT(i) == gain) {
+ ads1100_set_config_bits(data, ADS1100_PGA_MASK, i);
+ return 0;
+ }
+ }
Andy's suggestion of something like..
if (!gain)
return -EINVAL;
i = ffs(gain);
if (i >= 4 || BIT(i) != gain)
return -EINVAL;
ads...
Is perhaps nicer than the loop.
Yes, takes out a loop.
+static void ads1100_disable_continuous(void *data)
+{
+ ads1100_set_config_bits(data, ADS1100_CFG_SC, ADS1100_SINGLESHOT);
+}
+
+static int ads1100_probe(struct i2c_client *client)
+{
+ struct iio_dev *indio_dev;
+ struct ads1100_data *data;
+ struct device *dev = &client->dev;
+ int ret;
+
+ indio_dev = devm_iio_device_alloc(dev, sizeof(*data));
+ if (!indio_dev)
+ return -ENOMEM;
+
+ data = iio_priv(indio_dev);
+ i2c_set_clientdata(client, indio_dev);
You can avoid the slightly nasty mix of i2c_set_clientdata vs dev_get_drvdata()
below by taking advantage of the fact you have a local dev pointer.
dev_set_drvdata(dev, indio_dev);
and no confusing mix is left. Of course it's doing the same thing but to my
mind slightly nicer to use the same one.
Since I don't need indio_dev anywhere, I might as well say this directly:
dev_set_drvdata(dev, data);
(Only the pm_ routines use this)
...
--
Mike Looijmans
