linux-kernel - Re: [RESEND PATCH v2] hwmon: (max6639) : Configure based on DT property

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Message-ID: <7ef01e93-f714-4704-85da-1a06940d56b6@roeck-us.net>
Date: Fri, 11 Oct 2024 13:02:51 -0700
From: Guenter Roeck <linux@...ck-us.net>
To: Naresh Solanki <naresh.solanki@...ements.com>
Cc: Jean Delvare <jdelvare@...e.com>, linux-kernel@...r.kernel.org,
	linux-hwmon@...r.kernel.org
Subject: Re: [RESEND PATCH v2] hwmon: (max6639) : Configure based on DT
 property

On Mon, Oct 07, 2024 at 02:34:24PM +0530, Naresh Solanki wrote:
> Remove platform data & initialize with defaults
> configuration & overwrite based on DT properties.
> 
> Signed-off-by: Naresh Solanki <naresh.solanki@...ements.com>

Applied, with minor changes. See below.

Thanks,
Guenter

> ---
> Changes in V2:
> - Allow initializing the driver with defaults & overrid based on DT
>   properties if specified.
> - Remove unrelated changes.
> - Optimise ppr check to remove unacceptable range.
> ---
>  drivers/hwmon/max6639.c               | 85 +++++++++++++++++++--------
>  include/linux/platform_data/max6639.h | 15 -----
>  2 files changed, 62 insertions(+), 38 deletions(-)
>  delete mode 100644 include/linux/platform_data/max6639.h
> 
> diff --git a/drivers/hwmon/max6639.c b/drivers/hwmon/max6639.c
> index c955b0f3a8d3..6eacb5aed96d 100644
> --- a/drivers/hwmon/max6639.c
> +++ b/drivers/hwmon/max6639.c
> @@ -19,7 +19,6 @@
>  #include <linux/hwmon-sysfs.h>
>  #include <linux/err.h>
>  #include <linux/mutex.h>
> -#include <linux/platform_data/max6639.h>
>  #include <linux/regmap.h>
>  #include <linux/util_macros.h>
>  
> @@ -531,14 +530,51 @@ static int rpm_range_to_reg(int range)
>  	return 1; /* default: 4000 RPM */
>  }
>  
> +static int max6639_probe_child_from_dt(struct i2c_client *client,
> +				       struct device_node *child,
> +				       struct max6639_data *data)
> +
> +{
> +	struct device *dev = &client->dev;
> +	u32 i;
> +	int err, val;
> +
> +	err = of_property_read_u32(child, "reg", &i);
> +	if (err) {
> +		dev_err(dev, "missing reg property of %pOFn\n", child);
> +		return err;
> +	}
> +
> +	if (i > 1) {
> +		dev_err(dev, "Invalid fan index reg %d\n", i);
> +		return -EINVAL;
> +	}
> +
> +	err = of_property_read_u32(child, "pulses-per-revolution", &val);
> +

Dropped such empty lines for consistency.

> +	if (!err) {
> +		if (val < 1 || val > 5) {
> +			dev_err(dev, "invalid pulses-per-revolution %d of %pOFn\n", val, child);
> +			return -EINVAL;
> +		}
> +		data->ppr[i] = val;
> +	}
> +
> +	err = of_property_read_u32(child, "max-rpm", &val);
> +
> +	if (!err)
> +		data->rpm_range[i] = rpm_range_to_reg(val);
> +
> +	return 0;
> +}
> +
>  static int max6639_init_client(struct i2c_client *client,
>  			       struct max6639_data *data)
>  {
> -	struct max6639_platform_data *max6639_info =
> -		dev_get_platdata(&client->dev);
> -	int i;
> -	int rpm_range = 1; /* default: 4000 RPM */
> -	int err, ppr;
> +	struct device *dev = &client->dev;
> +	const struct device_node *np = dev->of_node;
> +	struct device_node *child;
> +	int i, err;
>  
>  	/* Reset chip to default values, see below for GCONFIG setup */
>  	err = regmap_write(data->regmap, MAX6639_REG_GCONFIG, MAX6639_GCONFIG_POR);
> @@ -546,21 +582,29 @@ static int max6639_init_client(struct i2c_client *client,
>  		return err;
>  
>  	/* Fans pulse per revolution is 2 by default */
> -	if (max6639_info && max6639_info->ppr > 0 &&
> -			max6639_info->ppr < 5)
> -		ppr = max6639_info->ppr;
> -	else
> -		ppr = 2;
> +	data->ppr[0] = 2;
> +	data->ppr[1] = 2;
>  
> -	data->ppr[0] = ppr;
> -	data->ppr[1] = ppr;
> +	/* default: 4000 RPM */
> +	data->rpm_range[0] = 1;
> +	data->rpm_range[1] = 1;
>  
> -	if (max6639_info)
> -		rpm_range = rpm_range_to_reg(max6639_info->rpm_range);
> -	data->rpm_range[0] = rpm_range;
> -	data->rpm_range[1] = rpm_range;
> +	for_each_child_of_node(np, child) {
> +		if (strcmp(child->name, "fan"))
> +			continue;
> +
> +		err = max6639_probe_child_from_dt(client, child, data);
> +		if (err) {
> +			of_node_put(child);
> +			return err;
> +		}
> +	}
>  
>  	for (i = 0; i < MAX6639_NUM_CHANNELS; i++) {
> +		err = regmap_set_bits(data->regmap, MAX6639_REG_OUTPUT_MASK, BIT(1 - i));
> +		if (err)
> +			return err;
> +
>  		/* Set Fan pulse per revolution */
>  		err = max6639_set_ppr(data, i, data->ppr[i]);
>  		if (err)
> @@ -573,12 +617,7 @@ static int max6639_init_client(struct i2c_client *client,
>  			return err;
>  
>  		/* Fans PWM polarity high by default */
> -		if (max6639_info) {
> -			if (max6639_info->pwm_polarity == 0)
> -				err = regmap_write(data->regmap, MAX6639_REG_FAN_CONFIG2a(i), 0x00);
> -			else
> -				err = regmap_write(data->regmap, MAX6639_REG_FAN_CONFIG2a(i), 0x02);
> -		}
> +		err = regmap_write(data->regmap, MAX6639_REG_FAN_CONFIG2a(i), 0x00);
>  		if (err)
>  			return err;
>  
> diff --git a/include/linux/platform_data/max6639.h b/include/linux/platform_data/max6639.h
> deleted file mode 100644
> index 65bfdb4fdc15..000000000000
> --- a/include/linux/platform_data/max6639.h
> +++ /dev/null
> @@ -1,15 +0,0 @@
> -/* SPDX-License-Identifier: GPL-2.0 */
> -#ifndef _LINUX_MAX6639_H
> -#define _LINUX_MAX6639_H
> -
> -#include <linux/types.h>
> -
> -/* platform data for the MAX6639 temperature sensor and fan control */
> -
> -struct max6639_platform_data {
> -	bool pwm_polarity;	/* Polarity low (0) or high (1, default) */
> -	int ppr;		/* Pulses per rotation 1..4 (default == 2) */
> -	int rpm_range;		/* 2000, 4000 (default), 8000 or 16000 */
> -};
> -
> -#endif /* _LINUX_MAX6639_H */