summaryrefslogtreecommitdiff
path: root/drivers/regulator
diff options
context:
space:
mode:
authorMark Brown <broonie@opensource.wolfsonmicro.com>2011-03-30 01:29:12 +0400
committerLiam Girdwood <lrg@slimlogic.co.uk>2011-05-27 13:34:35 +0400
commit2c6082341d1896218ca974cc2bb6876e36fcba5c (patch)
treef5ca00b3402eb36a0581c4481787ede5a4be5c72 /drivers/regulator
parentdc7acbb2518f250050179c8581a972df3b6a24f1 (diff)
downloadlinux-2c6082341d1896218ca974cc2bb6876e36fcba5c.tar.xz
regulator: When constraining modes fall back to higher power modes
If a mode requested by a consumer is not allowed by constraints automatically fall back to a higher power mode if possible. This ensures that consumers get at least the output they requested while allowing machine drivers to transparently limit lower power modes if required. Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
Diffstat (limited to 'drivers/regulator')
-rw-r--r--drivers/regulator/core.c24
1 files changed, 15 insertions, 9 deletions
diff --git a/drivers/regulator/core.c b/drivers/regulator/core.c
index 0fae51c4845a..7104404a9fa7 100644
--- a/drivers/regulator/core.c
+++ b/drivers/regulator/core.c
@@ -197,9 +197,9 @@ static int regulator_check_current_limit(struct regulator_dev *rdev,
}
/* operating mode constraint check */
-static int regulator_check_mode(struct regulator_dev *rdev, int mode)
+static int regulator_mode_constrain(struct regulator_dev *rdev, int *mode)
{
- switch (mode) {
+ switch (*mode) {
case REGULATOR_MODE_FAST:
case REGULATOR_MODE_NORMAL:
case REGULATOR_MODE_IDLE:
@@ -217,11 +217,17 @@ static int regulator_check_mode(struct regulator_dev *rdev, int mode)
rdev_err(rdev, "operation not allowed\n");
return -EPERM;
}
- if (!(rdev->constraints->valid_modes_mask & mode)) {
- rdev_err(rdev, "invalid mode %x\n", mode);
- return -EINVAL;
+
+ /* The modes are bitmasks, the most power hungry modes having
+ * the lowest values. If the requested mode isn't supported
+ * try higher modes. */
+ while (*mode) {
+ if (rdev->constraints->valid_modes_mask & *mode)
+ return 0;
+ *mode /= 2;
}
- return 0;
+
+ return -EINVAL;
}
/* dynamic regulator mode switching constraint check */
@@ -612,7 +618,7 @@ static void drms_uA_update(struct regulator_dev *rdev)
output_uV, current_uA);
/* check the new mode is allowed */
- err = regulator_check_mode(rdev, mode);
+ err = regulator_mode_constrain(rdev, &mode);
if (err == 0)
rdev->desc->ops->set_mode(rdev, mode);
}
@@ -2005,7 +2011,7 @@ int regulator_set_mode(struct regulator *regulator, unsigned int mode)
}
/* constraints check */
- ret = regulator_check_mode(rdev, mode);
+ ret = regulator_mode_constrain(rdev, mode);
if (ret < 0)
goto out;
@@ -2116,7 +2122,7 @@ int regulator_set_optimum_mode(struct regulator *regulator, int uA_load)
mode = rdev->desc->ops->get_optimum_mode(rdev,
input_uV, output_uV,
total_uA_load);
- ret = regulator_check_mode(rdev, mode);
+ ret = regulator_mode_constrain(rdev, &mode);
if (ret < 0) {
rdev_err(rdev, "failed to get optimum mode @ %d uA %d -> %d uV\n",
total_uA_load, input_uV, output_uV);