ACPI: add support for Smart Battery

Most batteries today are ACPI "Control Method" batteries,
but some models ship with the older "Smart Battery"
that requires this code.

Rich Townsend and Bruno Ducrot were the original authors.
Vladimir Lebedev updated to run on latest kernel.

http://bugzilla.kernel.org/show_bug.cgi?id=3734

Signed-off-by: Len Brown <len.brown@intel.com>

1 files changed, 135 insertions, 0 deletions

diff --git a/drivers/acpi/cm_sbs.c b/drivers/acpi/cm_sbs.c
new file mode 100644
index 000000000000..d11507c7b8a4
--- /dev/null
+++ b/drivers/acpi/cm_sbs.c
@@ -0,0 +1,135 @@
+/*
+ * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or (at
+ *  your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful, but
+ *  WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ *  General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License along
+ *  with this program; if not, write to the Free Software Foundation, Inc.,
+ *  59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
+ *
+ * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/acpi.h>
+#include <linux/types.h>
+#include <linux/proc_fs.h>
+#include <linux/seq_file.h>
+#include <acpi/acpi_bus.h>
+#include <acpi/acpi_drivers.h>
+#include <acpi/acmacros.h>
+#include <acpi/actypes.h>
+#include <acpi/acutils.h>
+
+ACPI_MODULE_NAME("cm_sbs")
+#define ACPI_AC_CLASS		"ac_adapter"
+#define ACPI_BATTERY_CLASS	"battery"
+#define ACPI_SBS_COMPONENT	0x00080000
+#define _COMPONENT		ACPI_SBS_COMPONENT
+static struct proc_dir_entry *acpi_ac_dir;
+static struct proc_dir_entry *acpi_battery_dir;
+
+static struct semaphore cm_sbs_sem;
+
+static int lock_ac_dir_cnt = 0;
+static int lock_battery_dir_cnt = 0;
+
+struct proc_dir_entry *acpi_lock_ac_dir(void)
+{
+	ACPI_FUNCTION_TRACE("acpi_lock_ac_dir");
+
+	down(&cm_sbs_sem);
+	if (!acpi_ac_dir) {
+		acpi_ac_dir = proc_mkdir(ACPI_AC_CLASS, acpi_root_dir);
+	}
+	if (acpi_ac_dir) {
+		lock_ac_dir_cnt++;
+	} else {
+		ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
+				  "Cannot create %s\n", ACPI_AC_CLASS));
+	}
+	up(&cm_sbs_sem);
+	return (acpi_ac_dir);
+}
+
+EXPORT_SYMBOL(acpi_lock_ac_dir);
+
+void acpi_unlock_ac_dir(struct proc_dir_entry *acpi_ac_dir_param)
+{
+	ACPI_FUNCTION_TRACE("acpi_unlock_ac_dir");
+
+	down(&cm_sbs_sem);
+	if (acpi_ac_dir_param) {
+		lock_ac_dir_cnt--;
+	}
+	if (lock_ac_dir_cnt == 0 && acpi_ac_dir_param && acpi_ac_dir) {
+		remove_proc_entry(ACPI_AC_CLASS, acpi_root_dir);
+		acpi_ac_dir = 0;
+	}
+	up(&cm_sbs_sem);
+}
+
+EXPORT_SYMBOL(acpi_unlock_ac_dir);
+
+struct proc_dir_entry *acpi_lock_battery_dir(void)
+{
+	ACPI_FUNCTION_TRACE("acpi_lock_battery_dir");
+
+	down(&cm_sbs_sem);
+	if (!acpi_battery_dir) {
+		acpi_battery_dir =
+		    proc_mkdir(ACPI_BATTERY_CLASS, acpi_root_dir);
+	}
+	if (acpi_battery_dir) {
+		lock_battery_dir_cnt++;
+	} else {
+		ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
+				  "Cannot create %s\n", ACPI_BATTERY_CLASS));
+	}
+	up(&cm_sbs_sem);
+	return (acpi_battery_dir);
+}
+
+EXPORT_SYMBOL(acpi_lock_battery_dir);
+
+void acpi_unlock_battery_dir(struct proc_dir_entry *acpi_battery_dir_param)
+{
+	ACPI_FUNCTION_TRACE("acpi_unlock_battery_dir");
+
+	down(&cm_sbs_sem);
+	if (acpi_battery_dir_param) {
+		lock_battery_dir_cnt--;
+	}
+	if (lock_battery_dir_cnt == 0 && acpi_battery_dir_param
+	    && acpi_battery_dir) {
+		remove_proc_entry(ACPI_BATTERY_CLASS, acpi_root_dir);
+		acpi_battery_dir = 0;
+	}
+	up(&cm_sbs_sem);
+}
+
+EXPORT_SYMBOL(acpi_unlock_battery_dir);
+
+static int __init acpi_cm_sbs_init(void)
+{
+	ACPI_FUNCTION_TRACE("acpi_cm_sbs_init");
+
+	if (acpi_disabled)
+		return_VALUE(0);
+
+	init_MUTEX(&cm_sbs_sem);
+
+	return_VALUE(0);
+}
+
+subsys_initcall(acpi_cm_sbs_init);