Re: [PATCH v1 2/2] hwmon: pmbus: Add ltc4286 driver

[Guenter Roeck]

On 4/25/23 06:45, Andi Shyti wrote:
> Hi Delphine,
>
> On top of Guenter's comments,
>
> [...]
>
> > +config SENSORS_LTC4286
> > +	bool "Linear Technologies LTC4286"
> > +	help
> > +	  If you say yes here you get hardware monitoring support for Linear
> > +	  Technology LTC4286.
>
> could you add a couple of words more here?
>
> [...]
>
> > +static int ltc4286_probe(struct i2c_client *client,
> > +			 const struct i2c_device_id *id)
> > +{
> > +	int ret;
> > +	u8 block_buffer[I2C_SMBUS_BLOCK_MAX + 1];
> > +	struct device *dev = &client->dev;
> > +	struct pmbus_driver_info *info;
> > +	u32 rsense;
> > +
> > +	ret = i2c_smbus_read_block_data(client, PMBUS_MFR_ID, block_buffer);
> > +	if (ret < 0) {
> > +		dev_err(&client->dev, "failed to read manufacturer id\n");
>
> you can use dev_err_probe() here:
>
> 	return dev_err_probe(&client->dev, err, "failed to read manufacturer id\n");
>
> > +		return ret;
> > +	}
> > +
> > +	/* Refer to ltc4286 datasheet page 20
> > +	 * the default manufacturer id is LTC
> > +	 */
> > +	if (ret != LTC4286_MFR_ID_SIZE ||
> > +	    strncmp(block_buffer, "LTC", LTC4286_MFR_ID_SIZE)) {
> > +		dev_err(&client->dev, "unsupported manufacturer id\n");
> > +		return -ENODEV;
> > +	}
> > +
> > +	ret = i2c_smbus_read_block_data(client, PMBUS_MFR_MODEL, block_buffer);
> > +	if (ret < 0) {
> > +		dev_err(&client->dev, "failed to read manufacturer model\n");
> > +		return ret;
> > +	}
>
> Is this read really needed?

It only makes sense if the returned string is actually validated.
Otherwise no.

Guenter