Re: [PATCH v3 11/19] hwmon: (mr75203) add VM pre-scaler support

From: Andy Shevchenko
Date: Wed Aug 31 2022 - 08:03:01 EST


On Tue, Aug 30, 2022 at 07:22:04PM +0000, Eliav Farber wrote:
> Add mr76006 pre-scaler support to normalize the voltage output result for
> channels that use pre-scaler units to get the measurement to be within
> the range that the sensor supports.
>
> For channels that are listed in the device-tree to have a pre-scaler, the
> voltage result is multiplied by a factor of 2, to represent to the user
> the actual voltage source which is measured.

...

> +static int pvt_get_pre_scaler(struct device *dev, struct pvt_device *pvt)
> +{
> + const struct device_node *np = dev->of_node;
> + u32 total_channels = pvt->vm_channels.total;
> + u32 channel;
> + u8 *pre_scaler_ch_list;
> + int i, ret, num_ch;
> +
> + /* Set default pre-scaler value to be 1. */
> + for (i = 0; i < total_channels; i++)
> + pvt->vd[i].pre_scaler = PRE_SCALER_X1;
> +
> + /* Get number of channels configured in "moortec,vm-pre-scaler". */
> + num_ch = of_property_count_u8_elems(np, "moortec,vm-pre-scaler");

of_ ?!

> + if (num_ch <= 0)
> + return 0;
> +
> + pre_scaler_ch_list = kcalloc(total_channels,
> + sizeof(*pre_scaler_ch_list), GFP_KERNEL);
> + if (!pre_scaler_ch_list)
> + return -ENOMEM;
> +
> + /* Get list of all channels that have pre-scaler of 2. */
> + ret = device_property_read_u8_array(dev, "moortec,vm-pre-scaler",
> + pre_scaler_ch_list, num_ch);
> + if (ret)
> + goto out;
> +
> + for (i = 0; i < num_ch; i++) {
> + channel = pre_scaler_ch_list[i];

> +

Unnecessary blank line.

> + if (channel >= total_channels) {
> + dev_err(dev,
> + "invalid channel (%u) in pre-scaler list\n",
> + channel);
> + ret = -EINVAL;

> + goto out;

Wouldn't

break;

suffice? (I understand the point, up to you)

> + }
> +
> + pvt->vd[channel].pre_scaler = PRE_SCALER_X2;
> + }
> +
> +out:

out_free:

> + kfree(pre_scaler_ch_list);
> +
> + return ret;
> +}


--
With Best Regards,
Andy Shevchenko