ACPI: property: Fix return value for nval == 0 in acpi_data_prop_read()

[ Upstream commit ab930483eca9f3e816c35824b5868599af0c61d7 ]

While analysing code for software and OF node for the corner case when
caller asks to read zero items in the supposed to be an array of values
I found that ACPI behaves differently to what OF does, i.e.

 1. It returns -EINVAL when caller asks to read zero items from integer
    array, while OF returns 0, if no other errors happened.

 2. It returns -EINVAL when caller asks to read zero items from string
    array, while OF returns -ENODATA, if no other errors happened.

Amend ACPI implementation to follow what OF does.

Fixes: b31384fa5d ("Driver core: Unified device properties interface for platform firmware")
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://patch.msgid.link/20250203194629.3731895-1-andriy.shevchenko@linux.intel.com
[ rjw: Added empty line after a conditional ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Andy Shevchenko 2025-02-03 21:46:29 +02:00 committed by Greg Kroah-Hartman
parent b960062afa
commit db4ae28790
1 changed files with 5 additions and 5 deletions

View File

@ -1116,8 +1116,6 @@ static int acpi_data_prop_read(const struct acpi_device_data *data,
}
break;
}
if (nval == 0)
return -EINVAL;
if (obj->type == ACPI_TYPE_BUFFER) {
if (proptype != DEV_PROP_U8)
@ -1141,9 +1139,11 @@ static int acpi_data_prop_read(const struct acpi_device_data *data,
ret = acpi_copy_property_array_uint(items, (u64 *)val, nval);
break;
case DEV_PROP_STRING:
ret = acpi_copy_property_array_string(
items, (char **)val,
min_t(u32, nval, obj->package.count));
nval = min_t(u32, nval, obj->package.count);
if (nval == 0)
return -ENODATA;
ret = acpi_copy_property_array_string(items, (char **)val, nval);
break;
default:
ret = -EINVAL;