2 files changed, 28 insertions, 14 deletions

diff --git a/drivers/hwmon/lis3lv02d.c b/drivers/hwmon/lis3lv02d.c
index b12ee359d90..39b9ac8e18e 100644
--- a/drivers/hwmon/lis3lv02d.c
+++ b/drivers/hwmon/lis3lv02d.c
@@ -50,6 +50,9 @@
  * joystick.
  */
 
+#define LIS3_PWRON_DELAY_WAI_12B        (5000)
+#define LIS3_PWRON_DELAY_WAI_8B         (3000)
+
 struct lis3lv02d lis3_dev = {
         .misc_wait   = __WAIT_QUEUE_HEAD_INITIALIZER(lis3_dev.misc_wait),
 };
@@ -112,6 +115,24 @@ static void lis3lv02d_get_xyz(struct lis3lv02d *lis3, int *x, int *y, int *z)
         *z = lis3lv02d_get_axis(lis3->ac.z, position);
 }
 
+/* conversion btw sampling rate and the register values */
+static int lis3_12_rates[4] = {40, 160, 640, 2560};
+static int lis3_8_rates[2] = {100, 400};
+
+static int lis3lv02d_get_odr(void)
+{
+        u8 ctrl;
+        int val;
+
+        lis3_dev.read(&lis3_dev, CTRL_REG1, &ctrl);
+
+        if (lis3_dev.whoami == WAI_12B)
+                val = lis3_12_rates[(ctrl & (CTRL1_DF0 | CTRL1_DF1)) >> 4];
+        else
+                val = lis3_8_rates[(ctrl & CTRL1_DR) >> 7];
+        return val;
+}
+
 void lis3lv02d_poweroff(struct lis3lv02d *lis3)
 {
         /* disable X,Y,Z axis and power down */
@@ -125,6 +146,9 @@ void lis3lv02d_poweron(struct lis3lv02d *lis3)
 
         lis3->init(lis3);
 
+        /* LIS3 power on delay is quite long */
+        msleep(lis3->pwron_delay / lis3lv02d_get_odr());
+
         /*
          * Common configuration
          * BDU: (12 bits sensors only) LSB and MSB values are not updated until
@@ -364,23 +388,10 @@ static ssize_t lis3lv02d_calibrate_store(struct device *dev,
         return count;
 }
 
-/* conversion btw sampling rate and the register values */
-static int lis3_12_rates[4] = {40, 160, 640, 2560};
-static int lis3_8_rates[2] = {100, 400};
 static ssize_t lis3lv02d_rate_show(struct device *dev,
                         struct device_attribute *attr, char *buf)
 {
-        u8 ctrl;
-        int val;
-
-        lis3_dev.read(&lis3_dev, CTRL_REG1, &ctrl);
-
-        if (lis3_dev.whoami == WAI_12B)
-                val = lis3_12_rates[(ctrl & (CTRL1_DF0 | CTRL1_DF1)) >> 4];
-        else
-                val = lis3_8_rates[(ctrl & CTRL1_DR) >> 7];
-
-        return sprintf(buf, "%d\n", val);
+        return sprintf(buf, "%d\n", lis3lv02d_get_odr());
 }
 
 static DEVICE_ATTR(position, S_IRUGO, lis3lv02d_position_show, NULL);
@@ -430,11 +441,13 @@ int lis3lv02d_init_device(struct lis3lv02d *dev)
                 printk(KERN_INFO DRIVER_NAME ": 12 bits sensor found\n");
                 dev->read_data = lis3lv02d_read_12;
                 dev->mdps_max_val = 2048;
+                dev->pwron_delay = LIS3_PWRON_DELAY_WAI_12B;
                 break;
         case WAI_8B:
                 printk(KERN_INFO DRIVER_NAME ": 8 bits sensor found\n");
                 dev->read_data = lis3lv02d_read_8;
                 dev->mdps_max_val = 128;
+                dev->pwron_delay = LIS3_PWRON_DELAY_WAI_8B;
                 break;
         default:
                 printk(KERN_ERR DRIVER_NAME
diff --git a/drivers/hwmon/lis3lv02d.h b/drivers/hwmon/lis3lv02d.h
index c6ae507e4f1..c57f21f4567 100644
--- a/drivers/hwmon/lis3lv02d.h
+++ b/drivers/hwmon/lis3lv02d.h
@@ -202,6 +202,7 @@ struct lis3lv02d {
         u8                      whoami;    /* indicates measurement precision */
         s16 (*read_data) (struct lis3lv02d *lis3, int reg);
         int                     mdps_max_val;
+        int                     pwron_delay;
 
         struct input_polled_dev *idev;     /* input device */
         struct platform_device  *pdev;     /* platform device */