Re: [PATCH v5 1/2] ACPI: utils: Add api to read _SUB from ACPI

Andy Shevchenko
2022-07-05T19:06:05Z

On Thu, Jun 30, 2022 at 5:17 PM Stefan Binding
<sbinding@opensource.cirrus.com> wrote:
>
> Add a wrapper function to read the _SUB string from ACPI.

...

> + if (obj->type == ACPI_TYPE_STRING) {
> + if (strlen(obj->string.pointer) < ACPI_MAX_SUB_BUF_SIZE &&
> + strlen(obj->string.pointer) > 0) {
> + sub = kstrdup(obj->string.pointer, GFP_KERNEL);
> + if (!sub)
> + sub = ERR_PTR(-ENOMEM);
> + } else {
> + acpi_handle_err(handle, "ACPI _SUB Length %zu is Invalid\n",
> + strlen(obj->string.pointer));

Three times to evaluate strlen()... Can we do better, please?

> + sub = ERR_PTR(-EINVAL);
> + }
> + } else {
> + acpi_handle_warn(handle, "Warning ACPI _SUB did not return a string\n");
> + sub = ERR_PTR(-EINVAL);
> + }

--
With Best Regards,
Andy Shevchenko