regulator: Bootstrap wm831x DVS VSEL value from ON VSEL if not already set

If we don't have a DVS VSEL value already set when we start up then start
it off with the value currently being used for ON.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>

1 files changed, 14 insertions, 0 deletions

diff --git a/drivers/regulator/wm831x-dcdc.c b/drivers/regulator/wm831x-dcdc.c
index 95249f7a0e39..2c5d54b026c9 100644
--- a/drivers/regulator/wm831x-dcdc.c
+++ b/drivers/regulator/wm831x-dcdc.c
@@ -491,6 +491,20 @@ static __devinit void wm831x_buckv_dvs_init(struct wm831x_dcdc *dcdc,
                 return;
         }
 
+        /* If DVS_VSEL is set to the minimum value then raise it to ON_VSEL
+         * to make bootstrapping a bit smoother.
+         */
+        if (!dcdc->dvs_vsel) {
+                ret = wm831x_set_bits(wm831x,
+                                      dcdc->base + WM831X_DCDC_DVS_CONTROL,
+                                      WM831X_DC1_DVS_VSEL_MASK, dcdc->on_vsel);
+                if (ret == 0)
+                        dcdc->dvs_vsel = dcdc->on_vsel;
+                else
+                        dev_warn(wm831x->dev, "Failed to set DVS_VSEL: %d\n",
+                                 ret);
+        }
+
         ret = wm831x_set_bits(wm831x, dcdc->base + WM831X_DCDC_DVS_CONTROL,
                               WM831X_DC1_DVS_SRC_MASK, ctrl);
         if (ret < 0) {