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mmc: core: Return 1 from mmc_regulator_set_vqmmc() if switch skipped

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Adjust mmc_regulator_set_vqmmc() to return 1 if the voltage switch was
skipped because the regulator voltage was already correct. This allows
drivers to detect such condition and possibly skip various voltage
switching extras.

Signed-off-by: Marek Vasut <marex@denx.de>
Link: https://lore.kernel.org/r/20200416163649.336967-2-marex@denx.de
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
This commit is contained in:
Marek Vasut 2020-04-16 18:36:48 +02:00 committed by Ulf Hansson
parent 9cbe0fc8cd
commit 17a0751e60
1 changed files with 14 additions and 3 deletions
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17
drivers/mmc/core/regulator.c
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@ -136,6 +136,8 @@ static int mmc_regulator_set_voltage_if_supported(struct regulator *regulator,
int min_uV, int target_uV,
int max_uV)
{
int current_uV;
/*
* Check if supported first to avoid errors since we may try several
* signal levels during power up and don't want to show errors.
@ -143,6 +145,14 @@ static int mmc_regulator_set_voltage_if_supported(struct regulator *regulator,
if (!regulator_is_supported_voltage(regulator, min_uV, max_uV))
return -EINVAL;
/*
* The voltage is already set, no need to switch.
* Return 1 to indicate that no switch happened.
*/
current_uV = regulator_get_voltage(regulator);
if (current_uV == target_uV)
return 1;
return regulator_set_voltage_triplet(regulator, min_uV, target_uV,
max_uV);
}
@ -198,9 +208,10 @@ int mmc_regulator_set_vqmmc(struct mmc_host *mmc, struct mmc_ios *ios)
* voltage in two steps and try to stay close to vmmc
* with a 0.3V tolerance at first.
*/
if (!mmc_regulator_set_voltage_if_supported(mmc->supply.vqmmc,
min_uV, volt, max_uV))
return 0;
ret = mmc_regulator_set_voltage_if_supported(mmc->supply.vqmmc,
min_uV, volt, max_uV);
if (ret >= 0)
return ret;
return mmc_regulator_set_voltage_if_supported(mmc->supply.vqmmc,
2700000, volt, 3600000);