From 17a0751e60b123ce1a266155abf72acd936b7ecc Mon Sep 17 00:00:00 2001 From: Marek Vasut Date: Thu, 16 Apr 2020 18:36:48 +0200 Subject: mmc: core: Return 1 from mmc_regulator_set_vqmmc() if switch skipped 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 Link: https://lore.kernel.org/r/20200416163649.336967-2-marex@denx.de Signed-off-by: Ulf Hansson --- drivers/mmc/core/regulator.c | 17 ++++++++++++++--- 1 file changed, 14 insertions(+), 3 deletions(-) (limited to 'drivers/mmc') diff --git a/drivers/mmc/core/regulator.c b/drivers/mmc/core/regulator.c index b6febbcf8978..96b1d15045d6 100644 --- a/drivers/mmc/core/regulator.c +++ b/drivers/mmc/core/regulator.c @@ -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); -- cgit v1.2.3