x86/platform/olpc: Use a correct version when making up a battery node

The XO-1 and XO-1.5 batteries apparently differ in an ability to report
ambient temperature. We need to use a different compatible string for the
XO-1.5 battery.

Previously olpc_dt_fixup() used the presence of the battery node's
compatible property to decide whether the DT is up to date. Now we need
to look for a particular value in the compatible string, to decide

Signed-off-by: Lubomir Rintel <lkundrak@v3.sk>
Acked-by: Pavel Machek <pavel@ucw.cz>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>

1 files changed, 50 insertions, 14 deletions

diff --git a/arch/x86/platform/olpc/olpc_dt.c b/arch/x86/platform/olpc/olpc_dt.c
index 820236b511b3..0296c5b55e6f 100644
--- a/arch/x86/platform/olpc/olpc_dt.c
+++ b/arch/x86/platform/olpc/olpc_dt.c
@@ -220,10 +220,26 @@ static u32 __init olpc_dt_get_board_revision(void)
         return be32_to_cpu(rev);
 }
 
+int olpc_dt_compatible_match(phandle node, const char *compat)
+{
+        char buf[64], *p;
+        int plen, len;
+
+        plen = olpc_dt_getproperty(node, "compatible", buf, sizeof(buf));
+        if (plen <= 0)
+                return 0;
+
+        len = strlen(compat);
+        for (p = buf; p < buf + plen; p += strlen(p) + 1) {
+                if (strcmp(p, compat) == 0)
+                        return 1;
+        }
+
+        return 0;
+}
+
 void __init olpc_dt_fixup(void)
 {
-        int r;
-        char buf[64];
         phandle node;
         u32 board_rev;
 
@@ -231,22 +247,31 @@ void __init olpc_dt_fixup(void)
         if (!node)
                 return;
 
-        /*
-         * If the battery node has a compatible property, we are running a new
-         * enough firmware and don't have fixups to make.
-         */
-        r = olpc_dt_getproperty(node, "compatible", buf, sizeof(buf));
-        if (r > 0)
-                return;
-
-        pr_info("PROM DT: Old firmware detected, applying fixes\n");
-
         board_rev = olpc_dt_get_board_revision();
         if (!board_rev)
                 return;
 
         if (board_rev >= olpc_board_pre(0xd0)) {
-                /* XO-1.5: add dcon device */
+                /* XO-1.5 */
+
+                if (olpc_dt_compatible_match(node, "olpc,xo1.5-battery"))
+                        return;
+
+                /* Add olpc,xo1.5-battery compatible marker to battery node */
+                olpc_dt_interpret("\" /battery@0\" find-device");
+                olpc_dt_interpret("  \" olpc,xo1.5-battery\" +compatible");
+                olpc_dt_interpret("device-end");
+
+                if (olpc_dt_compatible_match(node, "olpc,xo1-battery")) {
+                        /*
+                         * If we have a olpc,xo1-battery compatible, then we're
+                         * running a new enough firmware that already has
+                         * the dcon node.
+                         */
+                        return;
+                }
+
+                /* Add dcon device */
                 olpc_dt_interpret("\" /pci/display@1\" find-device");
                 olpc_dt_interpret("  new-device");
                 olpc_dt_interpret("    \" dcon\" device-name");
@@ -254,7 +279,18 @@ void __init olpc_dt_fixup(void)
                 olpc_dt_interpret("  finish-device");
                 olpc_dt_interpret("device-end");
         } else {
-                /* XO-1: add dcon device, mark RTC as olpc,xo1-rtc */
+                /* XO-1 */
+
+                if (olpc_dt_compatible_match(node, "olpc,xo1-battery")) {
+                        /*
+                         * If we have a olpc,xo1-battery compatible, then we're
+                         * running a new enough firmware that already has
+                         * the dcon and RTC nodes.
+                         */
+                        return;
+                }
+
+                /* Add dcon device, mark RTC as olpc,xo1-rtc */
                 olpc_dt_interpret("\" /pci/display@1,1\" find-device");
                 olpc_dt_interpret("  new-device");
                 olpc_dt_interpret("    \" dcon\" device-name");