[PATCH v3] regulator: twl-regulator: Use DIV_ROUND_UP atappropriate places

From: Axel Lin
Date: Mon Apr 09 2012 - 20:28:49 EST


Use DIV_ROUND_UP ensures we set the voltage falls within the specified range.
Current code may set the voltage lower than the specified range.

For example:

vsel = (min_uV - 600000) / 125;
if (vsel % 100)
vsel += 100;
vsel /= 100;
vsel++

In the case min_uV is 712599 uV, the vsel will be 10. Then current code set
the voltage to 712500 uV which is lower than the specified range.

Signed-off-by: Axel Lin <axel.lin@xxxxxxxxx>
---
v3: Fix off-by-one for vsel, the vsel++ after DIV_ROUND_UP is required because
current code does subtract index by 1 in the list_voltage callback.
v2: Remove braces {} for single statement blocks

drivers/regulator/twl-regulator.c | 20 ++++----------------
1 files changed, 4 insertions(+), 16 deletions(-)

diff --git a/drivers/regulator/twl-regulator.c b/drivers/regulator/twl-regulator.c
index 964946f..5d19b42 100644
--- a/drivers/regulator/twl-regulator.c
+++ b/drivers/regulator/twl-regulator.c
@@ -806,10 +806,7 @@ twl6030smps_set_voltage(struct regulator_dev *rdev, int min_uV, int max_uV,
vsel = 0;
else if ((min_uV >= 600000) && (min_uV <= 1300000)) {
int calc_uV;
- vsel = (min_uV - 600000) / 125;
- if (vsel % 100)
- vsel += 100;
- vsel /= 100;
+ vsel = DIV_ROUND_UP(min_uV - 600000, 12500);
vsel++;
calc_uV = twl6030smps_list_voltage(rdev, vsel);
if (calc_uV > max_uV)
@@ -836,10 +833,7 @@ twl6030smps_set_voltage(struct regulator_dev *rdev, int min_uV, int max_uV,
vsel = 0;
else if ((min_uV >= 700000) && (min_uV <= 1420000)) {
int calc_uV;
- vsel = (min_uV - 700000) / 125;
- if (vsel % 100)
- vsel += 100;
- vsel /= 100;
+ vsel = DIV_ROUND_UP(min_uV - 700000, 12500);
vsel++;
calc_uV = twl6030smps_list_voltage(rdev, vsel);
if (calc_uV > max_uV)
@@ -865,10 +859,7 @@ twl6030smps_set_voltage(struct regulator_dev *rdev, int min_uV, int max_uV,
if (min_uV == 0)
vsel = 0;
else if ((min_uV >= 1852000) && (max_uV <= 4013600)) {
- vsel = (min_uV - 1852000) / 386;
- if (vsel % 100)
- vsel += 100;
- vsel /= 100;
+ vsel = DIV_ROUND_UP(min_uV - 1852000, 38600);
vsel++;
}
break;
@@ -876,10 +867,7 @@ twl6030smps_set_voltage(struct regulator_dev *rdev, int min_uV, int max_uV,
if (min_uV == 0)
vsel = 0;
else if ((min_uV >= 2161000) && (max_uV <= 4321000)) {
- vsel = (min_uV - 2161000) / 386;
- if (vsel % 100)
- vsel += 100;
- vsel /= 100;
+ vsel = DIV_ROUND_UP(min_uV - 2161000, 38600);
vsel++;
}
break;
--
1.7.5.4



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