eeepc-laptop: get the right value for CMSG

CMSG is an ACPI method used to find features available on
an Eee PC. But some features are never repported, even if present.

If the getter of a feature is present, this patch will set
the corresponding bit in cmsg.

Signed-off-by: Corentin Chary <corentincj@iksaif.net>
Signed-off-by: Len Brown <len.brown@intel.com>
diff --git a/drivers/platform/x86/eeepc-laptop.c b/drivers/platform/x86/eeepc-laptop.c
index 19cc9ae..f5d8473 100644
--- a/drivers/platform/x86/eeepc-laptop.c
+++ b/drivers/platform/x86/eeepc-laptop.c
@@ -553,6 +553,28 @@
 	return -EINVAL;
 }
 
+static void cmsg_quirk(int cm, const char *name)
+{
+	int dummy;
+
+	/* Some BIOSes do not report cm although it is avaliable.
+	   Check if cm_getv[cm] works and, if yes, assume cm should be set. */
+	if (!(ehotk->cm_supported & (1 << cm))
+	    && !read_acpi_int(ehotk->handle, cm_getv[cm], &dummy)) {
+		pr_info("%s (%x) not reported by BIOS,"
+			" enabling anyway\n", name, 1 << cm);
+		ehotk->cm_supported |= 1 << cm;
+	}
+}
+
+static void cmsg_quirks(void)
+{
+	cmsg_quirk(CM_ASL_LID, "LID");
+	cmsg_quirk(CM_ASL_TYPE, "TYPE");
+	cmsg_quirk(CM_ASL_PANELPOWER, "PANELPOWER");
+	cmsg_quirk(CM_ASL_TPD, "TPD");
+}
+
 static int eeepc_hotk_check(void)
 {
 	const struct key_entry *key;
@@ -576,6 +598,7 @@
 			pr_err("Get control methods supported failed\n");
 			return -ENODEV;
 		} else {
+			cmsg_quirks();
 			pr_info("Get control methods supported: 0x%x\n",
 				ehotk->cm_supported);
 		}