regulator: twl: Fix the formula to calculate vsel and voltage for twl6030ldo
In twl6030ldo_set_voltage, current code use below formula to calculate vsel:
vsel = (min_uV/1000 - 1000)/100 + 1;
This is worng because when min_uV is 1000000 uV, vsel is 1.
It should be 0 in this case.
Fix it by change the equation to: (This equation is common for linear mapping)
vsel = DIV_ROUND_UP(min_uV - rdev->desc->min_uV, rdev->desc->uV_step);
In twl6030ldo_get_voltage, current code use below formula to calculate voltage:
mV = 1000mv + 100mv * (vsel - 1)
This is worng because when vsel is 0, mV is 900mV. Note the min_uV is 1000mV.
Fix it by change the equation to: (This equation is common for linear mapping)
return rdev->desc->min_uV + vsel * rdev->desc->uV_step;
Signed-off-by: Axel Lin <axel.lin@gmail.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
diff --git a/drivers/regulator/twl-regulator.c b/drivers/regulator/twl-regulator.c
index 8f0bd56..bb51dec 100644
--- a/drivers/regulator/twl-regulator.c
+++ b/drivers/regulator/twl-regulator.c
@@ -569,30 +569,21 @@
if ((min_uV/1000 < info->min_mV) || (max_uV/1000 > info->max_mV))
return -EDOM;
- /*
- * Use the below formula to calculate vsel
- * mV = 1000mv + 100mv * (vsel - 1)
- */
- vsel = (min_uV/1000 - 1000)/100 + 1;
+ vsel = DIV_ROUND_UP(min_uV - rdev->desc->min_uV, rdev->desc->uV_step);
*selector = vsel;
- return twlreg_write(info, TWL_MODULE_PM_RECEIVER, VREG_VOLTAGE, vsel);
+ return twlreg_write(info, TWL_MODULE_PM_RECEIVER, VREG_VOLTAGE, vsel);
}
static int twl6030ldo_get_voltage(struct regulator_dev *rdev)
{
struct twlreg_info *info = rdev_get_drvdata(rdev);
- int vsel = twlreg_read(info, TWL_MODULE_PM_RECEIVER,
- VREG_VOLTAGE);
+ int vsel = twlreg_read(info, TWL_MODULE_PM_RECEIVER, VREG_VOLTAGE);
if (vsel < 0)
return vsel;
- /*
- * Use the below formula to calculate vsel
- * mV = 1000mv + 100mv * (vsel - 1)
- */
- return (1000 + (100 * (vsel - 1))) * 1000;
+ return rdev->desc->min_uV + vsel * rdev->desc->uV_step;
}
static struct regulator_ops twl6030ldo_ops = {