Commit 2c608234 authored by Mark Brown's avatar Mark Brown Committed by Liam Girdwood
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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: default avatarMark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: default avatarLiam Girdwood <lrg@slimlogic.co.uk>
parent dc7acbb2

drivers/regulator/core.c

+15 −9
Original line number Diff line number Diff line
@@ -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 -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);