hp-wmi: check query return value in hp_wmi_perform_query

Check BIOS provided return value code in hp_wmi_perform_query and print
a warning on error. Printing is suppressed for HPWMI_RET_UNKNOWN_CMDTYPE
which is returned when the command type is unsupported.

Signed-off-by: Anssi Hannula <anssi.hannula@iki.fi>
Signed-off-by: Matthew Garrett <mjg@redhat.com>

1 files changed, 16 insertions, 0 deletions

diff --git a/drivers/platform/x86/hp-wmi.c b/drivers/platform/x86/hp-wmi.c
index 9e05af9c41cb..87dfb2489762 100644
--- a/drivers/platform/x86/hp-wmi.c
+++ b/drivers/platform/x86/hp-wmi.c
@@ -89,6 +89,13 @@ struct bios_return {
         u32 value;
 };
 
+enum hp_return_value {
+        HPWMI_RET_WRONG_SIGNATURE       = 0x02,
+        HPWMI_RET_UNKNOWN_COMMAND       = 0x03,
+        HPWMI_RET_UNKNOWN_CMDTYPE       = 0x04,
+        HPWMI_RET_INVALID_PARAMETERS    = 0x05,
+};
+
 static const struct key_entry hp_wmi_keymap[] = {
         { KE_KEY, 0x02,   { KEY_BRIGHTNESSUP } },
         { KE_KEY, 0x03,   { KEY_BRIGHTNESSDOWN } },
@@ -171,6 +178,15 @@ static int hp_wmi_perform_query(int query, int write, u32 *buffer,
 
         bios_return = *((struct bios_return *)obj->buffer.pointer);
 
+        if (bios_return.return_code) {
+                if (bios_return.return_code != HPWMI_RET_UNKNOWN_CMDTYPE)
+                        printk(KERN_WARNING PREFIX "query 0x%x returned "
+                                                   "error 0x%x\n",
+                               query, bios_return.return_code);
+                kfree(obj);
+                return bios_return.return_code;
+        }
+
         memcpy(buffer, &bios_return.value, sizeof(bios_return.value));
 
         kfree(obj);