Re: [PATCH v4 1/4] hwmon: (pmbus) Introduce and use write_byte_data callback

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

On Thu, Apr 28, 2022 at 04:40:36PM +0200, Mårten Lindahl wrote:
> Some of the pmbus core functions uses pmbus_write_byte_data, which does
> not support driver callbacks for chip specific write operations. This
> could potentially influence some specific regulator chips that for
> example need a time delay before each data access.
> 
> Lets add support for driver callback with _pmbus_write_byte_data.
> 
> Signed-off-by: Mårten Lindahl <marten.lindahl@axis.com>

Applied.

Thanks,
Guenter

> ---
>  drivers/hwmon/pmbus/pmbus.h      |  2 ++
>  drivers/hwmon/pmbus/pmbus_core.c | 24 +++++++++++++++++++++---
>  2 files changed, 23 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/hwmon/pmbus/pmbus.h b/drivers/hwmon/pmbus/pmbus.h
> index e74b6ef070f3..c031a9700ace 100644
> --- a/drivers/hwmon/pmbus/pmbus.h
> +++ b/drivers/hwmon/pmbus/pmbus.h
> @@ -438,6 +438,8 @@ struct pmbus_driver_info {
>  	int (*read_byte_data)(struct i2c_client *client, int page, int reg);
>  	int (*read_word_data)(struct i2c_client *client, int page, int phase,
>  			      int reg);
> +	int (*write_byte_data)(struct i2c_client *client, int page, int reg,
> +			      u8 byte);
>  	int (*write_word_data)(struct i2c_client *client, int page, int reg,
>  			       u16 word);
>  	int (*write_byte)(struct i2c_client *client, int page, u8 value);
> diff --git a/drivers/hwmon/pmbus/pmbus_core.c b/drivers/hwmon/pmbus/pmbus_core.c
> index b2618b1d529e..98da2db3f831 100644
> --- a/drivers/hwmon/pmbus/pmbus_core.c
> +++ b/drivers/hwmon/pmbus/pmbus_core.c
> @@ -276,6 +276,24 @@ static int _pmbus_write_word_data(struct i2c_client *client, int page, int reg,
>  	return pmbus_write_word_data(client, page, reg, word);
>  }
>  
> +/*
> + * _pmbus_write_byte_data() is similar to pmbus_write_byte_data(), but checks if
> + * a device specific mapping function exists and calls it if necessary.
> + */
> +static int _pmbus_write_byte_data(struct i2c_client *client, int page, int reg, u8 value)
> +{
> +	struct pmbus_data *data = i2c_get_clientdata(client);
> +	const struct pmbus_driver_info *info = data->info;
> +	int status;
> +
> +	if (info->write_byte_data) {
> +		status = info->write_byte_data(client, page, reg, value);
> +		if (status != -ENODATA)
> +			return status;
> +	}
> +	return pmbus_write_byte_data(client, page, reg, value);
> +}
> +
>  int pmbus_update_fan(struct i2c_client *client, int page, int id,
>  		     u8 config, u8 mask, u16 command)
>  {
> @@ -290,7 +308,7 @@ int pmbus_update_fan(struct i2c_client *client, int page, int id,
>  
>  	to = (from & ~mask) | (config & mask);
>  	if (to != from) {
> -		rv = pmbus_write_byte_data(client, page,
> +		rv = _pmbus_write_byte_data(client, page,
>  					   pmbus_fan_config_registers[id], to);
>  		if (rv < 0)
>  			return rv;
> @@ -397,7 +415,7 @@ int pmbus_update_byte_data(struct i2c_client *client, int page, u8 reg,
>  	tmp = (rv & ~mask) | (value & mask);
>  
>  	if (tmp != rv)
> -		rv = pmbus_write_byte_data(client, page, reg, tmp);
> +		rv = _pmbus_write_byte_data(client, page, reg, tmp);
>  
>  	return rv;
>  }
> @@ -912,7 +930,7 @@ static int pmbus_get_boolean(struct i2c_client *client, struct pmbus_boolean *b,
>  
>  	regval = status & mask;
>  	if (regval) {
> -		ret = pmbus_write_byte_data(client, page, reg, regval);
> +		ret = _pmbus_write_byte_data(client, page, reg, regval);
>  		if (ret)
>  			goto unlock;
>  	}