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Subject[ 025/128] regulator: max8997: Use uV in voltage_map_desc
3.2-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Axel Lin <axel.lin@ingics.com>

commit bc3b7756b5ff66828acf7bc24f148d28b8d61108 upstream.

Current code does integer division (min_vol = min_uV / 1000) before pass
min_vol to max8997_get_voltage_proper_val().
So it is possible min_vol is truncated to a smaller value.

For example, if the request min_uV is 800900 for ldo.
min_vol = 800900 / 1000 = 800 (mV)
Then max8997_get_voltage_proper_val returns 800 mV for this case which is lower
than the requested voltage.

Use uV rather than mV in voltage_map_desc to prevent truncation by integer
division.

Signed-off-by: Axel Lin <axel.lin@ingics.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
[bwh: Backported to 3.2:
- Adjust context
- voltage_map_desc also has an n_bits field]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
---
drivers/regulator/max8997.c | 36 +++++++++++++++++-------------------
1 file changed, 17 insertions(+), 19 deletions(-)

--- a/drivers/regulator/max8997.c
+++ b/drivers/regulator/max8997.c
@@ -71,26 +71,26 @@ struct voltage_map_desc {
unsigned int n_bits;
};

-/* Voltage maps in mV */
+/* Voltage maps in uV */
static const struct voltage_map_desc ldo_voltage_map_desc = {
- .min = 800, .max = 3950, .step = 50, .n_bits = 6,
+ .min = 800000, .max = 3950000, .step = 50000, .n_bits = 6,
}; /* LDO1 ~ 18, 21 all */

static const struct voltage_map_desc buck1245_voltage_map_desc = {
- .min = 650, .max = 2225, .step = 25, .n_bits = 6,
+ .min = 650000, .max = 2225000, .step = 25000, .n_bits = 6,
}; /* Buck1, 2, 4, 5 */

static const struct voltage_map_desc buck37_voltage_map_desc = {
- .min = 750, .max = 3900, .step = 50, .n_bits = 6,
+ .min = 750000, .max = 3900000, .step = 50000, .n_bits = 6,
}; /* Buck3, 7 */

-/* current map in mA */
+/* current map in uA */
static const struct voltage_map_desc charger_current_map_desc = {
- .min = 200, .max = 950, .step = 50, .n_bits = 4,
+ .min = 200000, .max = 950000, .step = 50000, .n_bits = 4,
};

static const struct voltage_map_desc topoff_current_map_desc = {
- .min = 50, .max = 200, .step = 10, .n_bits = 4,
+ .min = 50000, .max = 200000, .step = 10000, .n_bits = 4,
};

static const struct voltage_map_desc *reg_voltage_map[] = {
@@ -199,7 +199,7 @@ static int max8997_list_voltage(struct r
if (val > desc->max)
return -EINVAL;

- return val * 1000;
+ return val;
}

static int max8997_get_enable_register(struct regulator_dev *rdev,
@@ -501,7 +501,6 @@ static int max8997_set_voltage_ldobuck(s
{
struct max8997_data *max8997 = rdev_get_drvdata(rdev);
struct i2c_client *i2c = max8997->iodev->i2c;
- int min_vol = min_uV / 1000, max_vol = max_uV / 1000;
const struct voltage_map_desc *desc;
int rid = max8997_get_rid(rdev);
int reg, shift = 0, mask, ret;
@@ -527,7 +526,7 @@ static int max8997_set_voltage_ldobuck(s

desc = reg_voltage_map[rid];

- i = max8997_get_voltage_proper_val(desc, min_vol, max_vol);
+ i = max8997_get_voltage_proper_val(desc, min_uV, max_uV);
if (i < 0)
return i;

@@ -546,7 +545,7 @@ static int max8997_set_voltage_ldobuck(s
/* If the voltage is increasing */
if (org < i)
udelay(DIV_ROUND_UP(desc->step * (i - org),
- max8997->ramp_delay));
+ max8997->ramp_delay * 1000));
}

return ret;
@@ -645,7 +644,6 @@ static int max8997_set_voltage_buck(stru
const struct voltage_map_desc *desc;
int new_val, new_idx, damage, tmp_val, tmp_idx, tmp_dmg;
bool gpio_dvs_mode = false;
- int min_vol = min_uV / 1000, max_vol = max_uV / 1000;

if (rid < MAX8997_BUCK1 || rid > MAX8997_BUCK7)
return -EINVAL;
@@ -670,7 +668,7 @@ static int max8997_set_voltage_buck(stru
selector);

desc = reg_voltage_map[rid];
- new_val = max8997_get_voltage_proper_val(desc, min_vol, max_vol);
+ new_val = max8997_get_voltage_proper_val(desc, min_uV, max_uV);
if (new_val < 0)
return new_val;

@@ -1002,8 +1000,8 @@ static __devinit int max8997_pmic_probe(
max8997->buck1_vol[i] = ret =
max8997_get_voltage_proper_val(
&buck1245_voltage_map_desc,
- pdata->buck1_voltage[i] / 1000,
- pdata->buck1_voltage[i] / 1000 +
+ pdata->buck1_voltage[i],
+ pdata->buck1_voltage[i] +
buck1245_voltage_map_desc.step);
if (ret < 0)
goto err_alloc;
@@ -1011,8 +1009,8 @@ static __devinit int max8997_pmic_probe(
max8997->buck2_vol[i] = ret =
max8997_get_voltage_proper_val(
&buck1245_voltage_map_desc,
- pdata->buck2_voltage[i] / 1000,
- pdata->buck2_voltage[i] / 1000 +
+ pdata->buck2_voltage[i],
+ pdata->buck2_voltage[i] +
buck1245_voltage_map_desc.step);
if (ret < 0)
goto err_alloc;
@@ -1020,8 +1018,8 @@ static __devinit int max8997_pmic_probe(
max8997->buck5_vol[i] = ret =
max8997_get_voltage_proper_val(
&buck1245_voltage_map_desc,
- pdata->buck5_voltage[i] / 1000,
- pdata->buck5_voltage[i] / 1000 +
+ pdata->buck5_voltage[i],
+ pdata->buck5_voltage[i] +
buck1245_voltage_map_desc.step);
if (ret < 0)
goto err_alloc;



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