Pull d-states into release branch

[linux-2.6] / drivers / misc / thinkpad_acpi.c

diff --git a/drivers/misc/thinkpad_acpi.c b/drivers/misc/thinkpad_acpi.c
index 84a1000e4cec4e112be63dff38da8eedc2a1e686..f15a58f7403fd4b231ddd267ebb02f098d22957b 100644 (file)
--- a/drivers/misc/thinkpad_acpi.c
+++ b/drivers/misc/thinkpad_acpi.c
@@ -21,7 +21,7 @@
  *  02110-1301, USA.
  */
 
-#define IBM_VERSION "0.14"
+#define IBM_VERSION "0.15"
 #define TPACPI_SYSFS_VERSION 0x010000
 
 /*
@@ -3000,12 +3000,16 @@ static struct backlight_ops ibm_backlight_data = {
         .update_status  = brightness_update_status,
 };
 
+static struct mutex brightness_mutex;
+
 static int __init brightness_init(struct ibm_init_struct *iibm)
 {
        int b;
 
        vdbg_printk(TPACPI_DBG_INIT, "initializing brightness subdriver\n");
 
+       mutex_init(&brightness_mutex);
+
        if (!brightness_mode) {
                if (thinkpad_id.vendor == PCI_VENDOR_ID_LENOVO)
                        brightness_mode = 2;
@@ -3092,27 +3096,44 @@ static int brightness_get(struct backlight_device *bd)
 
 static int brightness_set(int value)
 {
-       int cmos_cmd, inc, i;
-       int current_value = brightness_get(NULL);
+       int cmos_cmd, inc, i, res;
+       int current_value;
 
        if (value > 7)
                return -EINVAL;
 
+       res = mutex_lock_interruptible(&brightness_mutex);
+       if (res < 0)
+               return res;
+
+       current_value = brightness_get(NULL);
+       if (current_value < 0) {
+               res = current_value;
+               goto errout;
+       }
+
        cmos_cmd = value > current_value ?
                        TP_CMOS_BRIGHTNESS_UP :
                        TP_CMOS_BRIGHTNESS_DOWN;
        inc = value > current_value ? 1 : -1;
 
+       res = 0;
        for (i = current_value; i != value; i += inc) {
                if ((brightness_mode & 2) &&
-                   issue_thinkpad_cmos_command(cmos_cmd))
-                       return -EIO;
+                   issue_thinkpad_cmos_command(cmos_cmd)) {
+                       res = -EIO;
+                       goto errout;
+               }
                if ((brightness_mode & 1) &&
-                   !acpi_ec_write(brightness_offset, i + inc))
-                       return -EIO;
+                   !acpi_ec_write(brightness_offset, i + inc)) {
+                       res = -EIO;
+                       goto errout;;
+               }
        }
 
-       return 0;
+errout:
+       mutex_unlock(&brightness_mutex);
+       return res;
 }
 
 static int brightness_read(char *p)