of/flattree: Add of_flat_dt_match() helper function

This patch adds of_flat_dt_match() which tests a node for
compatibility with a list of values and converts the relevant powerpc
platform code to use it.  This approach simplifies the board support
code a bit.

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Reviewed-by: Stephen Neuendorffer <stephen.neuendorffer@xilinx.com>

11 files changed, 89 insertions, 78 deletions

diff --git a/arch/powerpc/platforms/40x/ppc40x_simple.c b/arch/powerpc/platforms/40x/ppc40x_simple.c
index 546bbc229d19..2521d93ef136 100644
--- a/arch/powerpc/platforms/40x/ppc40x_simple.c
+++ b/arch/powerpc/platforms/40x/ppc40x_simple.c
@@ -50,7 +50,7 @@ machine_device_initcall(ppc40x_simple, ppc40x_device_probe);
  * Again, if your board needs to do things differently then create a
  * board.c file for it rather than adding it to this list.
  */
-static char *board[] __initdata = {
+static const char *board[] __initdata = {
         "amcc,acadia",
         "amcc,haleakala",
         "amcc,kilauea",
@@ -60,14 +60,9 @@ static char *board[] __initdata = {
 
 static int __init ppc40x_probe(void)
 {
-        unsigned long root = of_get_flat_dt_root();
-        int i = 0;
-
-        for (i = 0; i < ARRAY_SIZE(board); i++) {
-                if (of_flat_dt_is_compatible(root, board[i])) {
-                        ppc_pci_set_flags(PPC_PCI_REASSIGN_ALL_RSRC);
-                        return 1;
-                }
+        if (of_flat_dt_match(of_get_flat_dt_root(), board)) {
+                ppc_pci_set_flags(PPC_PCI_REASSIGN_ALL_RSRC);
+                return 1;
         }
 
         return 0;
diff --git a/arch/powerpc/platforms/512x/mpc5121_generic.c b/arch/powerpc/platforms/512x/mpc5121_generic.c
index e487eb06ec6b..926731f1ff01 100644
--- a/arch/powerpc/platforms/512x/mpc5121_generic.c
+++ b/arch/powerpc/platforms/512x/mpc5121_generic.c
@@ -26,7 +26,7 @@
 /*
  * list of supported boards
  */
-static char *board[] __initdata = {
+static const char *board[] __initdata = {
         "prt,prtlvt",
         NULL
 };
@@ -36,16 +36,7 @@ static char *board[] __initdata = {
  */
 static int __init mpc5121_generic_probe(void)
 {
-        unsigned long node = of_get_flat_dt_root();
-        int i = 0;
-
-        while (board[i]) {
-                if (of_flat_dt_is_compatible(node, board[i]))
-                        break;
-                i++;
-        }
-
-        return board[i] != NULL;
+        return of_flat_dt_match(of_get_flat_dt_root(), board);
 }
 
 define_machine(mpc5121_generic) {
diff --git a/arch/powerpc/platforms/52xx/lite5200.c b/arch/powerpc/platforms/52xx/lite5200.c
index de55bc0584b5..01ffa64d2aa7 100644
--- a/arch/powerpc/platforms/52xx/lite5200.c
+++ b/arch/powerpc/platforms/52xx/lite5200.c
@@ -172,20 +172,18 @@ static void __init lite5200_setup_arch(void)
         mpc52xx_setup_pci();
 }
 
+static const char *board[] __initdata = {
+        "fsl,lite5200",
+        "fsl,lite5200b",
+        NULL,
+};
+
 /*
  * Called very early, MMU is off, device-tree isn't unflattened
  */
 static int __init lite5200_probe(void)
 {
-        unsigned long node = of_get_flat_dt_root();
-        const char *model = of_get_flat_dt_prop(node, "model", NULL);
-
-        if (!of_flat_dt_is_compatible(node, "fsl,lite5200") &&
-            !of_flat_dt_is_compatible(node, "fsl,lite5200b"))
-                return 0;
-        pr_debug("%s board found\n", model ? model : "unknown");
-
-        return 1;
+        return of_flat_dt_match(of_get_flat_dt_root(), board);
 }
 
 define_machine(lite5200) {
diff --git a/arch/powerpc/platforms/52xx/media5200.c b/arch/powerpc/platforms/52xx/media5200.c
index 0bac3a3dbecf..2c7780cb68e5 100644
--- a/arch/powerpc/platforms/52xx/media5200.c
+++ b/arch/powerpc/platforms/52xx/media5200.c
@@ -239,7 +239,7 @@ static void __init media5200_setup_arch(void)
 }
 
 /* list of the supported boards */
-static char *board[] __initdata = {
+static const char *board[] __initdata = {
         "fsl,media5200",
         NULL
 };
@@ -249,16 +249,7 @@ static char *board[] __initdata = {
  */
 static int __init media5200_probe(void)
 {
-        unsigned long node = of_get_flat_dt_root();
-        int i = 0;
-
-        while (board[i]) {
-                if (of_flat_dt_is_compatible(node, board[i]))
-                        break;
-                i++;
-        }
-
-        return (board[i] != NULL);
+        return of_flat_dt_match(of_get_flat_dt_root(), board);
 }
 
 define_machine(media5200_platform) {
diff --git a/arch/powerpc/platforms/52xx/mpc5200_simple.c b/arch/powerpc/platforms/52xx/mpc5200_simple.c
index d45be5b5ad49..e36d6e232ae6 100644
--- a/arch/powerpc/platforms/52xx/mpc5200_simple.c
+++ b/arch/powerpc/platforms/52xx/mpc5200_simple.c
@@ -49,7 +49,7 @@ static void __init mpc5200_simple_setup_arch(void)
 }
 
 /* list of the supported boards */
-static char *board[] __initdata = {
+static const char *board[] __initdata = {
         "intercontrol,digsy-mtc",
         "manroland,mucmc52",
         "manroland,uc101",
@@ -66,16 +66,7 @@ static char *board[] __initdata = {
  */
 static int __init mpc5200_simple_probe(void)
 {
-        unsigned long node = of_get_flat_dt_root();
-        int i = 0;
-
-        while (board[i]) {
-                if (of_flat_dt_is_compatible(node, board[i]))
-                        break;
-                i++;
-        }
-        
-        return (board[i] != NULL);
+        return of_flat_dt_match(of_get_flat_dt_root(), board);
 }
 
 define_machine(mpc5200_simple_platform) {
diff --git a/arch/powerpc/platforms/83xx/mpc830x_rdb.c b/arch/powerpc/platforms/83xx/mpc830x_rdb.c
index 846831d495b5..661d354e4ff2 100644
--- a/arch/powerpc/platforms/83xx/mpc830x_rdb.c
+++ b/arch/powerpc/platforms/83xx/mpc830x_rdb.c
@@ -57,16 +57,19 @@ static void __init mpc830x_rdb_init_IRQ(void)
         ipic_set_default_priority();
 }
 
+struct const char *board[] __initdata = {
+        "MPC8308RDB",
+        "fsl,mpc8308rdb",
+        "denx,mpc8308_p1m",
+        NULL
+}
+
 /*
  * Called very early, MMU is off, device-tree isn't unflattened
  */
 static int __init mpc830x_rdb_probe(void)
 {
-        unsigned long root = of_get_flat_dt_root();
-
-        return of_flat_dt_is_compatible(root, "MPC8308RDB") ||
-               of_flat_dt_is_compatible(root, "fsl,mpc8308rdb") ||
-               of_flat_dt_is_compatible(root, "denx,mpc8308_p1m");
+        return of_flat_dt_match(of_get_flat_dt_root(), board);
 }
 
 static struct of_device_id __initdata of_bus_ids[] = {
diff --git a/arch/powerpc/platforms/83xx/mpc831x_rdb.c b/arch/powerpc/platforms/83xx/mpc831x_rdb.c
index ae525e4745d2..b54cd736a895 100644
--- a/arch/powerpc/platforms/83xx/mpc831x_rdb.c
+++ b/arch/powerpc/platforms/83xx/mpc831x_rdb.c
@@ -60,15 +60,18 @@ static void __init mpc831x_rdb_init_IRQ(void)
         ipic_set_default_priority();
 }
 
+struct const char *board[] __initdata = {
+        "MPC8313ERDB",
+        "fsl,mpc8315erdb",
+        NULL
+}
+
 /*
  * Called very early, MMU is off, device-tree isn't unflattened
  */
 static int __init mpc831x_rdb_probe(void)
 {
-        unsigned long root = of_get_flat_dt_root();
-
-        return of_flat_dt_is_compatible(root, "MPC8313ERDB") ||
-               of_flat_dt_is_compatible(root, "fsl,mpc8315erdb");
+        return of_flat_dt_match(of_get_flat_dt_root(), board);
 }
 
 static struct of_device_id __initdata of_bus_ids[] = {
diff --git a/arch/powerpc/platforms/83xx/mpc837x_rdb.c b/arch/powerpc/platforms/83xx/mpc837x_rdb.c
index 910caa6b5810..7bafbf2ec0f9 100644
--- a/arch/powerpc/platforms/83xx/mpc837x_rdb.c
+++ b/arch/powerpc/platforms/83xx/mpc837x_rdb.c
@@ -101,17 +101,20 @@ static void __init mpc837x_rdb_init_IRQ(void)
         ipic_set_default_priority();
 }
 
+static const char *board[] __initdata = {
+        "fsl,mpc8377rdb",
+        "fsl,mpc8378rdb",
+        "fsl,mpc8379rdb",
+        "fsl,mpc8377wlan",
+        NULL
+};
+
 /*
  * Called very early, MMU is off, device-tree isn't unflattened
  */
 static int __init mpc837x_rdb_probe(void)
 {
-        unsigned long root = of_get_flat_dt_root();
-
-        return of_flat_dt_is_compatible(root, "fsl,mpc8377rdb") ||
-               of_flat_dt_is_compatible(root, "fsl,mpc8378rdb") ||
-               of_flat_dt_is_compatible(root, "fsl,mpc8379rdb") ||
-               of_flat_dt_is_compatible(root, "fsl,mpc8377wlan");
+        return of_flat_dt_match(of_get_flat_dt_root(), board);
 }
 
 define_machine(mpc837x_rdb) {
diff --git a/arch/powerpc/platforms/85xx/tqm85xx.c b/arch/powerpc/platforms/85xx/tqm85xx.c
index 8f29bbce5360..5e847d0b47c8 100644
--- a/arch/powerpc/platforms/85xx/tqm85xx.c
+++ b/arch/powerpc/platforms/85xx/tqm85xx.c
@@ -186,21 +186,21 @@ static int __init declare_of_platform_devices(void)
 }
 machine_device_initcall(tqm85xx, declare_of_platform_devices);
 
+static const char *board[] __initdata = {
+        "tqc,tqm8540",
+        "tqc,tqm8541",
+        "tqc,tqm8548",
+        "tqc,tqm8555",
+        "tqc,tqm8560",
+        NULL
+};
+
 /*
  * Called very early, device-tree isn't unflattened
  */
 static int __init tqm85xx_probe(void)
 {
-        unsigned long root = of_get_flat_dt_root();
-
-        if ((of_flat_dt_is_compatible(root, "tqc,tqm8540")) ||
-            (of_flat_dt_is_compatible(root, "tqc,tqm8541")) ||
-            (of_flat_dt_is_compatible(root, "tqc,tqm8548")) ||
-            (of_flat_dt_is_compatible(root, "tqc,tqm8555")) ||
-            (of_flat_dt_is_compatible(root, "tqc,tqm8560")))
-                return 1;
-
-        return 0;
+        return of_flat_dt_match(of_get_flat_dt_root(), board);
 }
 
 define_machine(tqm85xx) {
diff --git a/drivers/of/fdt.c b/drivers/of/fdt.c
index 8a90ee42071a..c787c3d95c60 100644
--- a/drivers/of/fdt.c
+++ b/drivers/of/fdt.c
@@ -78,19 +78,23 @@ void *of_fdt_get_property(struct boot_param_header *blob,
  * @blob: A device tree blob
  * @node: node to test
  * @compat: compatible string to compare with compatible list.
+ *
+ * On match, returns a non-zero value with smaller values returned for more
+ * specific compatible values.
  */
 int of_fdt_is_compatible(struct boot_param_header *blob,
                       unsigned long node, const char *compat)
 {
         const char *cp;
-        unsigned long cplen, l;
+        unsigned long cplen, l, score = 0;
 
         cp = of_fdt_get_property(blob, node, "compatible", &cplen);
         if (cp == NULL)
                 return 0;
         while (cplen > 0) {
+                score++;
                 if (of_compat_cmp(cp, compat, strlen(compat)) == 0)
-                        return 1;
+                        return score;
                 l = strlen(cp) + 1;
                 cp += l;
                 cplen -= l;
@@ -99,6 +103,27 @@ int of_fdt_is_compatible(struct boot_param_header *blob,
         return 0;
 }
 
+/**
+ * of_fdt_match - Return true if node matches a list of compatible values
+ */
+int of_fdt_match(struct boot_param_header *blob, unsigned long node,
+                 const char **compat)
+{
+        unsigned int tmp, score = 0;
+
+        if (!compat)
+                return 0;
+
+        while (*compat) {
+                tmp = of_fdt_is_compatible(blob, node, *compat);
+                if (tmp && (score == 0 || (tmp < score)))
+                        score = tmp;
+                compat++;
+        }
+
+        return score;
+}
+
 static void *unflatten_dt_alloc(unsigned long *mem, unsigned long size,
                                        unsigned long align)
 {
@@ -511,6 +536,14 @@ int __init of_flat_dt_is_compatible(unsigned long node, const char *compat)
         return of_fdt_is_compatible(initial_boot_params, node, compat);
 }
 
+/**
+ * of_flat_dt_match - Return true if node matches a list of compatible values
+ */
+int __init of_flat_dt_match(unsigned long node, const char **compat)
+{
+        return of_fdt_match(initial_boot_params, node, compat);
+}
+
 #ifdef CONFIG_BLK_DEV_INITRD
 /**
  * early_init_dt_check_for_initrd - Decode initrd location from flat tree
diff --git a/include/linux/of_fdt.h b/include/linux/of_fdt.h
index 9ce5dfd2186a..ee96091f7d25 100644
--- a/include/linux/of_fdt.h
+++ b/include/linux/of_fdt.h
@@ -68,6 +68,8 @@ extern void *of_fdt_get_property(struct boot_param_header *blob,
 extern int of_fdt_is_compatible(struct boot_param_header *blob,
                                 unsigned long node,
                                 const char *compat);
+extern int of_fdt_match(struct boot_param_header *blob, unsigned long node,
+                        const char **compat);
 extern void of_fdt_unflatten_tree(unsigned long *blob,
                                struct device_node **mynodes);
 
@@ -84,6 +86,7 @@ extern int of_scan_flat_dt(int (*it)(unsigned long node, const char *uname,
 extern void *of_get_flat_dt_prop(unsigned long node, const char *name,
                                  unsigned long *size);
 extern int of_flat_dt_is_compatible(unsigned long node, const char *name);
+extern int of_flat_dt_match(unsigned long node, const char **matches);
 extern unsigned long of_get_flat_dt_root(void);
 
 extern int early_init_dt_scan_chosen(unsigned long node, const char *uname,