Re: [PATCH 3/4] iio: adc: Add support for the GE HealthCare PMC ADC

[David Lechner]

On Tue, Oct 1, 2024 at 2:47 AM Herve Codina <herve.codina@xxxxxxxxxxx> wrote:
>
> The GE HealthCare PMC Analog to Digital Converter (ADC) is a 16-Channel
> (voltage and current), 16-Bit ADC with an I2C Interface.
>
> Signed-off-by: Herve Codina <herve.codina@xxxxxxxxxxx>
> ---

...

> +static int pmc_adc_read_raw_ch(struct pmc_adc *pmc_adc, u8 cmd, int *val)
> +{
> +       s32 ret;
> +
> +       ret = i2c_smbus_read_word_swapped(pmc_adc->client, cmd);
> +       if (ret < 0) {
> +               dev_err(&pmc_adc->client->dev, "i2c read word failed (%d)\n", ret);
> +               return ret;
> +       }
> +
> +       *val = sign_extend32(ret, 16);

Shouldn't this be 15, not 16?

> +       return 0;
> +}
> +

...

> +
> +static int pmc_adc_probe(struct i2c_client *client)
> +{
> +       struct iio_dev *indio_dev;
> +       struct pmc_adc *pmc_adc;
> +       struct clk *clk;
> +       s32 val;
> +       int ret;
> +
> +       ret = devm_regulator_bulk_get_enable(&client->dev, ARRAY_SIZE(pmc_adc_regulator_names),
> +                                            pmc_adc_regulator_names);
> +       if (ret)
> +               return dev_err_probe(&client->dev, ret, "Failed to get regulators\n");
> +
> +       clk = devm_clk_get_optional_enabled(&client->dev, "osc");
> +       if (IS_ERR(clk))
> +               return dev_err_probe(&client->dev, PTR_ERR(clk), "Failed to get osc clock\n");
> +
> +       indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*pmc_adc));
> +       if (!indio_dev)
> +               return -ENOMEM;
> +
> +       pmc_adc = iio_priv(indio_dev);
> +       pmc_adc->client = client;
> +
> +       val = i2c_smbus_read_byte_data(pmc_adc->client, PMC_ADC_CMD_REQUEST_PROTOCOL_VERSION);
> +       if (val < 0)
> +               return dev_err_probe(&client->dev, val, "Failed to get protocol version\n");
> +
> +       if (val != 0x01) {
> +               dev_err(&client->dev, "Unsupported protocol version 0x%02x\n", val);

Use dev_err_probe?

> +               return -EINVAL;
> +       }
> +
> +       indio_dev->name = "pmc_adc";
> +       indio_dev->info = &pmc_adc_info;
> +       indio_dev->channels = pmc_adc_channels;
> +       indio_dev->num_channels = ARRAY_SIZE(pmc_adc_channels);
> +
> +       return devm_iio_device_register(&client->dev, indio_dev);
> +}