Re: [v3,1/2] hwmon: add MP2891 driver

[Christophe JAILLET]

Le 31/05/2024 à 09:26, Noah Wang a écrit :
> Add support for MPS VR controller mp2891. This driver exposes
> telemetry and limit value readings and writings.
>
> Signed-off-by: Noah Wang <noahwang.wang@xxxxxxxxxxx>
> ---

Hi,

below a few nitpicks, if it make sense to you.

...

> +++ b/drivers/hwmon/pmbus/mp2891.c
> @@ -0,0 +1,608 @@
> +// SPDX-License-Identifier: GPL-2.0-or-later
> +/*
> + * Hardware monitoring driver for MPS Multi-phase Digital VR Controllers(MP2891)
> + */
> +
> +#include <linux/err.h>
> +#include <linux/i2c.h>
> +#include <linux/init.h>
> +#include <linux/kernel.h>
> +#include <linux/module.h>
> +#include <linux/bitfield.h>

It is usually prefered to have includes sorted.

> +#include "pmbus.h"
> +

...

> +static struct pmbus_driver_info mp2891_info = {

I think this could be const.

> +	.pages = MP2891_PAGE_NUM,
> +	.format[PSC_VOLTAGE_IN] = direct,
> +	.format[PSC_CURRENT_IN] = direct,
> +	.format[PSC_CURRENT_OUT] = direct,
> +	.format[PSC_TEMPERATURE] = direct,
> +	.format[PSC_POWER] = direct,
> +	.format[PSC_VOLTAGE_OUT] = direct,
> +
> +	/* set vin scale 31.25mV/Lsb */
> +	.m[PSC_VOLTAGE_IN] = 32,
> +	.R[PSC_VOLTAGE_IN] = 0,
> +	.b[PSC_VOLTAGE_IN] = 0,
> +
> +	/* set temp scale 1000m°C/Lsb */
> +	.m[PSC_TEMPERATURE] = 1,
> +	.R[PSC_TEMPERATURE] = 0,
> +	.b[PSC_TEMPERATURE] = 0,
> +
> +	.m[PSC_CURRENT_IN] = 1,
> +	.R[PSC_CURRENT_IN] = 0,
> +	.b[PSC_CURRENT_IN] = 0,
> +
> +	.m[PSC_CURRENT_OUT] = 1,
> +	.R[PSC_CURRENT_OUT] = 0,
> +	.b[PSC_CURRENT_OUT] = 0,
> +
> +	.m[PSC_POWER] = 1,
> +	.R[PSC_POWER] = 0,
> +	.b[PSC_POWER] = 0,
> +
> +	.m[PSC_VOLTAGE_OUT] = 1,
> +	.R[PSC_VOLTAGE_OUT] = 3,
> +	.b[PSC_VOLTAGE_OUT] = 0,
> +
> +	.func[0] = MP2891_RAIL1_FUNC,
> +	.func[1] = MP2891_RAIL2_FUNC,
> +	.read_word_data = mp2891_read_word_data,
> +	.write_word_data = mp2891_write_word_data,
> +	.read_byte_data = mp2891_read_byte_data,
> +	.identify = mp2891_identify,
> +};
> +
> +static int mp2891_probe(struct i2c_client *client)
> +{
> +	struct pmbus_driver_info *info;
> +	struct mp2891_data *data;
> +
> +	data = devm_kzalloc(&client->dev, sizeof(struct mp2891_data), GFP_KERNEL);

sizeof(*data)?

> +	if (!data)
> +		return -ENOMEM;
> +
> +	memcpy(&data->info, &mp2891_info, sizeof(*info));
> +	info = &data->info;

'info' is not really useful. It could either be dropped, or initialised 
1 line above, so that it can be used in the memcpy().

CJ

> +
> +	return pmbus_do_probe(client, info);
> +}

...