[PATCH v2] dmioem: Decode Dell-specific DMI type 178

[Armin Wolf]

OEM DMI type 178 is used by the dell-wmi-base driver to translate
WMI event scancodes into hotkey events. Include the available
information in the output of dmidecode.

Signed-off-by: Armin Wolf <W_Armin@gmx.de>
---
Changes since v2:
- return early when count is zero
- rework *hotkey handling
---
 dmioem.c | 23 +++++++++++++++++++++++
 1 file changed, 23 insertions(+)

diff --git a/dmioem.c b/dmioem.c
index 964f287..1df77ec 100644
--- a/dmioem.c
+++ b/dmioem.c
@@ -144,6 +144,24 @@ static void dmi_dell_bios_flags(u64 flags)
        pr_attr("ACPI WMI Supported", "%s", (flags.l & (1 << 1)) ? "Yes" : 
"No");
 }

+static void dmi_dell_hotkeys(const struct dmi_header *h)
+{
+       int count = (h->length - 0x04) / 0x04;
+       u8 *hotkey = h->data + 0x04;
+
+       if (!count)
+               return;
+
+       pr_list_start("Hotkey Mappings", NULL);
+       for (int i = 0; i < count; i++)
+       {
+               pr_list_item("Scancode 0x%04hx -> Keycode 0x%04hx",
+                            WORD(hotkey + 0x00), WORD(hotkey + 0x02));
+               hotkey += 0x04;
+       }
+       pr_list_end();
+}
+
 static void dmi_dell_indexed_io_access(const struct dmi_header *h)
 {
        static const char *checksum_types[] = {
@@ -225,6 +243,11 @@ static int dmi_decode_dell(const struct dmi_header *h)
                        dmi_dell_bios_flags(QWORD(data + 0x04));
                        break;

+               case 178:
+                       pr_handle_name("Dell Hotkeys");
+                       dmi_dell_hotkeys(h);
+                       break;
+
                case 212:
                        pr_handle_name("Dell Indexed I/O Access");
                        if (h->length < 0x0C) break;
--
2.39.5