Re: [PATCH 2/3 v2] hwmon: (ntc_thermistor): Switch to generic firmware props

[Guenter Roeck <linux@roeck-us.net>]

On Mon, Dec 06, 2021 at 03:04:22AM +0100, Linus Walleij wrote:
> This switches to retrieveing the configuration of the NTC
> from generic firmware properties so that we get neutral from
> device tree: now ACPI or, more importantly, software nodes
> can be used to spawn NTC devices provided they have the
> required properties.
> 
> This was inspired by the similar changes made to the IIO
> drivers.
> 
> This was tested on the Ux500 HREF with the NTC devices
> probing from device tree just as fine after this as before.
> 
> Cc: Peter Rosin <peda@axentia.se>
> Cc: Chris Lesiak <chris.lesiak@licor.com>
> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

Applied.

Thanks,
Guenter

> ---
> ChangeLog v1->v2:
> - Rebase on the changes keeping the props parsing code in
>   a separate function.
> ---
>  drivers/hwmon/ntc_thermistor.c | 36 ++++++++++++++++++----------------
>  1 file changed, 19 insertions(+), 17 deletions(-)
> 
> diff --git a/drivers/hwmon/ntc_thermistor.c b/drivers/hwmon/ntc_thermistor.c
> index 12435ef66530..0c8b3dbcb38b 100644
> --- a/drivers/hwmon/ntc_thermistor.c
> +++ b/drivers/hwmon/ntc_thermistor.c
> @@ -9,10 +9,10 @@
>  #include <linux/slab.h>
>  #include <linux/module.h>
>  #include <linux/math64.h>
> +#include <linux/mod_devicetable.h>
>  #include <linux/platform_device.h>
> +#include <linux/property.h>
>  #include <linux/err.h>
> -#include <linux/of.h>
> -#include <linux/of_device.h>
>  #include <linux/fixp-arith.h>
>  #include <linux/iio/consumer.h>
>  #include <linux/hwmon.h>
> @@ -595,12 +595,11 @@ static const struct hwmon_chip_info ntc_chip_info = {
>  	.info = ntc_info,
>  };
>  
> -static int ntc_thermistor_parse_dt(struct device *dev,
> -				   struct ntc_data *data)
> +static int ntc_thermistor_parse_props(struct device *dev,
> +				      struct ntc_data *data)
>  {
>  	struct iio_channel *chan;
>  	enum iio_chan_type type;
> -	struct device_node *np = dev->of_node;
>  	int ret;
>  
>  	chan = devm_iio_channel_get(dev, NULL);
> @@ -614,14 +613,19 @@ static int ntc_thermistor_parse_dt(struct device *dev,
>  	if (type != IIO_VOLTAGE)
>  		return -EINVAL;
>  
> -	if (of_property_read_u32(np, "pullup-uv", &data->pullup_uv))
> -		return -ENODEV;
> -	if (of_property_read_u32(np, "pullup-ohm", &data->pullup_ohm))
> -		return -ENODEV;
> -	if (of_property_read_u32(np, "pulldown-ohm", &data->pulldown_ohm))
> -		return -ENODEV;
> +	ret = device_property_read_u32(dev, "pullup-uv", &data->pullup_uv);
> +	if (ret)
> +		return dev_err_probe(dev,  ret, "pullup-uv not specified\n");
> +
> +	ret = device_property_read_u32(dev, "pullup-ohm", &data->pullup_ohm);
> +	if (ret)
> +		return dev_err_probe(dev,  ret, "pullup-ohm not specified\n");
> +
> +	ret = device_property_read_u32(dev, "pulldown-ohm", &data->pulldown_ohm);
> +	if (ret)
> +		return dev_err_probe(dev,  ret, "pulldown-ohm not specified\n");
>  
> -	if (of_find_property(np, "connected-positive", NULL))
> +	if (device_property_read_bool(dev, "connected-positive"))
>  		data->connect = NTC_CONNECTED_POSITIVE;
>  	else /* status change should be possible if not always on. */
>  		data->connect = NTC_CONNECTED_GROUND;
> @@ -634,8 +638,6 @@ static int ntc_thermistor_parse_dt(struct device *dev,
>  static int ntc_thermistor_probe(struct platform_device *pdev)
>  {
>  	struct device *dev = &pdev->dev;
> -	const struct of_device_id *of_id =
> -			of_match_device(of_match_ptr(ntc_match), dev);
>  	const struct platform_device_id *pdev_id;
>  	struct device *hwmon_dev;
>  	struct ntc_data *data;
> @@ -645,7 +647,7 @@ static int ntc_thermistor_probe(struct platform_device *pdev)
>  	if (!data)
>  		return -ENOMEM;
>  
> -	ret = ntc_thermistor_parse_dt(dev, data);
> +	ret = ntc_thermistor_parse_props(dev, data);
>  	if (ret)
>  		return ret;
>  
> @@ -660,7 +662,7 @@ static int ntc_thermistor_probe(struct platform_device *pdev)
>  		return -EINVAL;
>  	}
>  
> -	pdev_id = of_id ? of_id->data : platform_get_device_id(pdev);
> +	pdev_id = device_get_match_data(dev);
>  
>  	if (pdev_id->driver_data >= ARRAY_SIZE(ntc_type)) {
>  		dev_err(dev, "Unknown device type: %lu(%s)\n",
> @@ -688,7 +690,7 @@ static int ntc_thermistor_probe(struct platform_device *pdev)
>  static struct platform_driver ntc_thermistor_driver = {
>  	.driver = {
>  		.name = "ntc-thermistor",
> -		.of_match_table = of_match_ptr(ntc_match),
> +		.of_match_table = ntc_match,
>  	},
>  	.probe = ntc_thermistor_probe,
>  	.id_table = ntc_thermistor_id,