Re: [PATCH 06/11] staging: iio: ad7746: Add dt-bindings

From: Jonathan Cameron
Date: Fri Mar 23 2018 - 08:47:04 EST


On Wed, 21 Mar 2018 11:28:54 -0300
Hernán Gonzalez <hernan@xxxxxxxxxxxxxxxxxxxx> wrote:

> This patch adds dt bindings by populating a pdata struct in order to
> modify as little as possible the existing code. It supports both
> platform_data and dt-bindings but uses only one depending on
> CONFIG_OF's value.
>
> Signed-off-by: Hernán Gonzalez <hernan@xxxxxxxxxxxxxxxxxxxx>
> ---
> drivers/staging/iio/cdc/ad7746.c | 55 +++++++++++++++++++++++++++++++++++++++-
> 1 file changed, 54 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/staging/iio/cdc/ad7746.c b/drivers/staging/iio/cdc/ad7746.c
> index cba8cd1..815573c 100644
> --- a/drivers/staging/iio/cdc/ad7746.c
> +++ b/drivers/staging/iio/cdc/ad7746.c
> @@ -658,6 +658,44 @@ static const struct iio_info ad7746_info = {
> /*
> * device probe and remove
> */
> +#ifdef CONFIG_OF
> +static struct ad7746_platform_data *ad7746_parse_dt(struct device *dev)
> +{
> + struct device_node *np = dev->of_node;
> + struct ad7746_platform_data *pdata;
> + unsigned int tmp;
> + int ret;
> +
> + /* The default excitation outputs are not inverted, it should be stated
> + * in the dt if needed.
> + */
> +
> + pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
> + if (!pdata)
> + return NULL;
> +
> + tmp = 0;
> + ret = of_property_read_u32(np, "adi,exclvl", &tmp);
It's not an optional read so why would temp be unset in any
paths where it is used?

> + if (ret || tmp > 3) {
> + dev_warn(dev, "Wrong exclvl value, using default\n");
> + pdata->exclvl = 3; /* default value */
> + } else {
> + pdata->exclvl = tmp;
> + }
> +
> + pdata->exca_inv_en = of_property_read_bool(np, "adi,nexca_en");
> + pdata->excb_inv_en = of_property_read_bool(np, "adi,nexcb_en");
> + pdata->exca_en = !pdata->exca_inv_en;
> + pdata->excb_en = !pdata->excb_inv_en;
> +
> + return pdata;
> +}
> +#else
> +static struct ad7746_platform_data *ad7746_parse_dt(struct device *dev)
> +{
> + return NULL;
> +}
> +#endif
>
> static int ad7746_probe(struct i2c_client *client,
> const struct i2c_device_id *id)
> @@ -668,6 +706,11 @@ static int ad7746_probe(struct i2c_client *client,
> unsigned char regval = 0;
> int ret = 0;
>
> + if (client->dev.of_node)
> + pdata = ad7746_parse_dt(&client->dev);
> + else
> + pdata = client->dev.platform_data;
> +
> indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*chip));
> if (!indio_dev)
> return -ENOMEM;
> @@ -731,12 +774,22 @@ static const struct i2c_device_id ad7746_id[] = {
> { "ad7747", 7747 },
> {}
> };
> -
> MODULE_DEVICE_TABLE(i2c, ad7746_id);
>
> +#ifdef CONFIG_OF
> +static const struct of_device_id ad7746_of_match[] = {
> + { .compatible = "adi,ad7745" },
> + { .compatible = "adi,ad7746" },
> + { .compatible = "adi,ad7747" },
> + { }
> +};
> +MODULE_DEVICE_TABLE(of, ad7746_of_match);
> +#endif
> +
> static struct i2c_driver ad7746_driver = {
> .driver = {
> .name = KBUILD_MODNAME,
> + .of_match_table = of_match_ptr(ad7746_of_match),
> },
> .probe = ad7746_probe,
> .id_table = ad7746_id,