ACPI: fix allowing to add/remove multiple _OSI strings

commit b0ed7a91(ACPICA/ACPI: Add new host interfaces for _OSI suppor)
introduced another regression that only one _OSI string can be added or
removed.

Now multiple _OSI strings can be added or removed, for example

acpi_osi=Linux acpi_osi=FreeBSD acpi_osi="!Windows 2006"

Signed-off-by: Lin Ming <ming.m.lin@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>

1 files changed, 50 insertions, 16 deletions

diff --git a/drivers/acpi/osl.c b/drivers/acpi/osl.c
index 6867443c494..d0a1bb54367 100644
--- a/drivers/acpi/osl.c
+++ b/drivers/acpi/osl.c
@@ -110,9 +110,6 @@ struct acpi_ioremap {
 static LIST_HEAD(acpi_ioremaps);
 static DEFINE_SPINLOCK(acpi_ioremap_lock);
 
-#define OSI_STRING_LENGTH_MAX 64        /* arbitrary */
-static char osi_setup_string[OSI_STRING_LENGTH_MAX];
-
 static void __init acpi_osi_setup_late(void);
 
 /*
@@ -1054,16 +1051,47 @@ static int __init acpi_os_name_setup(char *str)
 
 __setup("acpi_os_name=", acpi_os_name_setup);
 
+#define OSI_STRING_LENGTH_MAX 64        /* arbitrary */
+#define OSI_STRING_ENTRIES_MAX 16       /* arbitrary */
+
+struct osi_setup_entry {
+        char string[OSI_STRING_LENGTH_MAX];
+        bool enable;
+};
+
+static struct osi_setup_entry __initdata osi_setup_entries[OSI_STRING_ENTRIES_MAX];
+
 void __init acpi_osi_setup(char *str)
 {
+        struct osi_setup_entry *osi;
+        bool enable = true;
+        int i;
+
         if (!acpi_gbl_create_osi_method)
                 return;
 
         if (str == NULL || *str == '\0') {
                 printk(KERN_INFO PREFIX "_OSI method disabled\n");
                 acpi_gbl_create_osi_method = FALSE;
-        } else
-                strncpy(osi_setup_string, str, OSI_STRING_LENGTH_MAX);
+                return;
+        }
+
+        if (*str == '!') {
+                str++;
+                enable = false;
+        }
+
+        for (i = 0; i < OSI_STRING_ENTRIES_MAX; i++) {
+                osi = &osi_setup_entries[i];
+                if (!strcmp(osi->string, str)) {
+                        osi->enable = enable;
+                        break;
+                } else if (osi->string[0] == '\0') {
+                        osi->enable = enable;
+                        strncpy(osi->string, str, OSI_STRING_LENGTH_MAX);
+                        break;
+                }
+        }
 }
 
 static void __init set_osi_linux(unsigned int enable)
@@ -1110,22 +1138,28 @@ void __init acpi_dmi_osi_linux(int enable, const struct dmi_system_id *d)
  */
 static void __init acpi_osi_setup_late(void)
 {
-        char *str = osi_setup_string;
+        struct osi_setup_entry *osi;
+        char *str;
+        int i;
         acpi_status status;
 
-        if (*str == '\0')
-                return;
+        for (i = 0; i < OSI_STRING_ENTRIES_MAX; i++) {
+                osi = &osi_setup_entries[i];
+                str = osi->string;
 
-        if (*str == '!') {
-                status = acpi_remove_interface(++str);
+                if (*str == '\0')
+                        break;
+                if (osi->enable) {
+                        status = acpi_install_interface(str);
 
-                if (ACPI_SUCCESS(status))
-                        printk(KERN_INFO PREFIX "Deleted _OSI(%s)\n", str);
-        } else {
-                status = acpi_install_interface(str);
+                        if (ACPI_SUCCESS(status))
+                                printk(KERN_INFO PREFIX "Added _OSI(%s)\n", str);
+                } else {
+                        status = acpi_remove_interface(str);
 
-                if (ACPI_SUCCESS(status))
-                        printk(KERN_INFO PREFIX "Added _OSI(%s)\n", str);
+                        if (ACPI_SUCCESS(status))
+                                printk(KERN_INFO PREFIX "Deleted _OSI(%s)\n", str);
+                }
         }
 }