[PATCH RFT 1/2] regulator: twl: Fix checking voltage range in twl6030smps_set_voltage()

Axel Lin
2012-07-14T05:37:23Z

The voltage selection logic is supposed to find the samllest voltage falls
within specified range. When using equation to calculate vsel, we need to
ensure the requested min_uV meet the range of using the equation.
Otherwise we may select a voltage that is out of specified range.

For example, in the case vsel = 62 means select voltage of 2100000uV.
What we want is to ensure the requested min_uV <= 2100000 rather than checking
max_uV >= 2100000. And this also means in the case min_uV > 2100000, vsel = 62
does not meet the request.

Also calling twl6030smps_list_voltage() for all cases to ensure the selected
voltage still in bounds.

Signed-off-by: Axel Lin <axel.lin@gmail.com>
---
drivers/regulator/twl-regulator.c | 36 ++++++++++++++++--------------------
1 file changed, 16 insertions(+), 20 deletions(-)

diff --git a/drivers/regulator/twl-regulator.c b/drivers/regulator/twl-regulator.c
index 8f0bd56..03d0bea 100644
--- a/drivers/regulator/twl-regulator.c
+++ b/drivers/regulator/twl-regulator.c
@@ -760,32 +760,28 @@ twl6030smps_set_voltage(struct regulator_dev *rdev, int min_uV, int max_uV,
unsigned int *selector)
{
struct twlreg_info *info = rdev_get_drvdata(rdev);
- int vsel = 0;
+ int vsel = 0, calc_uV;

switch (info->flags) {
case 0:
if (min_uV == 0)
vsel = 0;
else if ((min_uV >= 600000) && (min_uV <= 1300000)) {
- int calc_uV;
vsel = DIV_ROUND_UP(min_uV - 600000, 12500);
vsel++;
- calc_uV = twl6030smps_list_voltage(rdev, vsel);
- if (calc_uV > max_uV)
- return -EINVAL;
}
/* Values 1..57 for vsel are linear and can be calculated
* values 58..62 are non linear.
*/
- else if ((min_uV > 1900000) && (max_uV >= 2100000))
+ else if ((min_uV > 1900000) && (min_uV <= 2100000))
vsel = 62;
- else if ((min_uV > 1800000) && (max_uV >= 1900000))
+ else if ((min_uV > 1800000) && (min_uV <= 1900000))
vsel = 61;
- else if ((min_uV > 1500000) && (max_uV >= 1800000))
+ else if ((min_uV > 1500000) && (min_uV <= 1800000))
vsel = 60;
- else if ((min_uV > 1350000) && (max_uV >= 1500000))
+ else if ((min_uV > 1350000) && (min_uV <= 1500000))
vsel = 59;
- else if ((min_uV > 1300000) && (max_uV >= 1350000))
+ else if ((min_uV > 1300000) && (min_uV <= 1350000))
vsel = 58;
else
return -EINVAL;
@@ -794,25 +790,21 @@ twl6030smps_set_voltage(struct regulator_dev *rdev, int min_uV, int max_uV,
if (min_uV == 0)
vsel = 0;
else if ((min_uV >= 700000) && (min_uV <= 1420000)) {
- int calc_uV;
vsel = DIV_ROUND_UP(min_uV - 700000, 12500);
vsel++;
- calc_uV = twl6030smps_list_voltage(rdev, vsel);
- if (calc_uV > max_uV)
- return -EINVAL;
}
/* Values 1..57 for vsel are linear and can be calculated
* values 58..62 are non linear.
*/
- else if ((min_uV > 1900000) && (max_uV >= 2100000))
+ else if ((min_uV > 1900000) && (min_uV <= 2100000))
vsel = 62;
- else if ((min_uV > 1800000) && (max_uV >= 1900000))
+ else if ((min_uV > 1800000) && (min_uV <= 1900000))
vsel = 61;
- else if ((min_uV > 1350000) && (max_uV >= 1800000))
+ else if ((min_uV > 1350000) && (min_uV <= 1800000))
vsel = 60;
- else if ((min_uV > 1350000) && (max_uV >= 1500000))
+ else if ((min_uV > 1350000) && (min_uV <= 1500000))
vsel = 59;
- else if ((min_uV > 1300000) && (max_uV >= 1350000))
+ else if ((min_uV > 1300000) && (min_uV <= 1350000))
vsel = 58;
else
return -EINVAL;
@@ -828,13 +820,17 @@ twl6030smps_set_voltage(struct regulator_dev *rdev, int min_uV, int max_uV,
case SMPS_OFFSET_EN|SMPS_EXTENDED_EN:
if (min_uV == 0) {
vsel = 0;
- } else if ((min_uV >= 2161000) && (max_uV <= 4321000)) {
+ } else if ((min_uV >= 2161000) && (min_uV <= 4321000)) {
vsel = DIV_ROUND_UP(min_uV - 2161000, 38600);
vsel++;
}
break;
}

+ calc_uV = twl6030smps_list_voltage(rdev, vsel);
+ if (calc_uV > max_uV)
+ return -EINVAL;
+
*selector = vsel;

return twlreg_write(info, TWL_MODULE_PM_RECEIVER, VREG_VOLTAGE_SMPS,
--
1.7.9.5