Re: [PATCH v5 1/1] hwmon: Add driver for Astera Labs PT5161L retimer

From: Guenter Roeck
Date: Mon Feb 05 2024 - 16:23:27 EST


On Mon, Feb 05, 2024 at 11:20:13PM +0800, Cosmo Chou wrote:
> This driver implements support for temperature monitoring of Astera Labs
> PT5161L series PCIe retimer chips.
>
> This driver implementation originates from the CSDK available at
> Link: https://github.com/facebook/openbmc/tree/helium/common/recipes-lib/retimer-v2.14
> The communication protocol utilized is based on the I2C/SMBus standard.
>
> Signed-off-by: Cosmo Chou <chou.cosmo@xxxxxxxxx>
> ---
[ ... ]

> +static ssize_t pt5161l_debugfs_read_fw_ver(struct file *file, char __user *buf,
> + size_t count, loff_t *ppos)
> +{
> + struct pt5161l_data *data = file->private_data;
> + int ret;
> + char ver[32];
> +
> + mutex_lock(&data->lock);
> + ret = pt5161l_fwsts_check(data);
> + mutex_unlock(&data->lock);
> + if (ret)
> + return ret;
> +
> + ret = snprintf(ver, sizeof(ver), "%u.%u.%u\n", data->fw_ver.major,
> + data->fw_ver.minor, data->fw_ver.build);
> + if (ret < 0)
> + return ret;
> +

You almost got me here ;-). snprintf() never returns a negative error code,
so checking for it is not necessary.

> + return simple_read_from_buffer(buf, count, ppos, ver, ret + 1);

Number of bytes written plus 1 ? Why ?

Thanks,
Guenter