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

[Delphine_CC_Chiu/WYHQ/Wiwynn]

> -----Original Message-----
> From: Andi Shyti <andi.shyti@xxxxxxxxxx>
> Sent: Tuesday, April 25, 2023 9:46 PM
> To: Delphine_CC_Chiu/WYHQ/Wiwynn <Delphine_CC_Chiu@xxxxxxxxxx>
> Cc: patrick@xxxxxxxxx; Guenter Roeck <linux@xxxxxxxxxxxx>; Jean Delvare
> <jdelvare@xxxxxxxx>; Rob Herring <robh+dt@xxxxxxxxxx>; Krzysztof Kozlowski
> <krzysztof.kozlowski+dt@xxxxxxxxxx>; linux-i2c@xxxxxxxxxxxxxxx;
> linux-hwmon@xxxxxxxxxxxxxxx; devicetree@xxxxxxxxxxxxxxx;
> linux-kernel@xxxxxxxxxxxxxxx
> Subject: Re: [PATCH v1 2/2] hwmon: pmbus: Add ltc4286 driver
> 
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> sender.
> 
> 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?
We will revise as below
       config SENSORS_LTC4286
	        bool "Analog Devices LTC4286"
            help
			  LTC4286 is an integrated solution for hot swap applications that allows 
			  a board to be safely inserted and removed from a live backplane.
			  This chip could be used to monitor voltage, current, ...etc.
              If you say yes here you get hardware monitoring support for Analog
              Devices LTC4286.

> 
> [...]
> 
> > +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:
We will revise as below
dev_err_probe(&client->dev, err, "failed to read manufacturer id\n");

> 
>         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?
We use this to check manufacturer model.
And we will add comparison here.
for (mid = ltc4286_id; mid->name[0]; mid++) {
if (!strncasecmp(mid->name, block_buffer, strlen(mid->name)))
	break;
} 

> 
> Andi
> 
> [...]