To allow an additional external regulator to be controlled by an mmc host driver, let's add support for a vqmmc2 regulator to the mmc core.
For an SD UHS-II interface the vqmmc2 regulator may correspond to the so called vdd2 supply, as described by the SD spec. Initially, only 1.8V is needed, hence limit the new helper function, mmc_regulator_set_vqmmc2() to this too. Note that, to allow for flexibility mmc host drivers need to manage the enable/disable of the vqmmc2 regulator themselves, while the regulator is looked up through the common mmc_regulator_get_supply(). Signed-off-by: Ulf Hansson <[email protected]> --- drivers/mmc/core/regulator.c | 34 ++++++++++++++++++++++++++++++++++ include/linux/mmc/host.h | 11 +++++++++++ 2 files changed, 45 insertions(+) diff --git a/drivers/mmc/core/regulator.c b/drivers/mmc/core/regulator.c index 609201a467ef..3c189682797c 100644 --- a/drivers/mmc/core/regulator.c +++ b/drivers/mmc/core/regulator.c @@ -223,6 +223,33 @@ int mmc_regulator_set_vqmmc(struct mmc_host *mmc, struct mmc_ios *ios) } EXPORT_SYMBOL_GPL(mmc_regulator_set_vqmmc); +/** + * mmc_regulator_set_vqmmc2 - Set vqmmc2 as per the ios->vqmmc2_voltage + * @mmc: The mmc host to regulate + * @ios: The io bus settings + * + * Sets a new voltage level for the vqmmc2 regulator, which may correspond to + * the vdd2 regulator for an SD UHS-II interface. This function is expected to + * be called by mmc host drivers. + * + * Returns a negative error code on failure, zero if the voltage level was + * changed successfully or a positive value if the level didn't need to change. + */ +int mmc_regulator_set_vqmmc2(struct mmc_host *mmc, struct mmc_ios *ios) +{ + if (IS_ERR(mmc->supply.vqmmc2)) + return -EINVAL; + + switch (ios->vqmmc2_voltage) { + case MMC_VQMMC2_VOLTAGE_180: + return mmc_regulator_set_voltage_if_supported( + mmc->supply.vqmmc2, 1700000, 1800000, 1950000); + default: + return -EINVAL; + } +} +EXPORT_SYMBOL_GPL(mmc_regulator_set_vqmmc2); + #else static inline int mmc_regulator_get_ocrmask(struct regulator *supply) @@ -249,6 +276,7 @@ int mmc_regulator_get_supply(struct mmc_host *mmc) mmc->supply.vmmc = devm_regulator_get_optional(dev, "vmmc"); mmc->supply.vqmmc = devm_regulator_get_optional(dev, "vqmmc"); + mmc->supply.vqmmc2 = devm_regulator_get_optional(dev, "vqmmc2"); if (IS_ERR(mmc->supply.vmmc)) { if (PTR_ERR(mmc->supply.vmmc) == -EPROBE_DEFER) @@ -268,6 +296,12 @@ int mmc_regulator_get_supply(struct mmc_host *mmc) dev_dbg(dev, "No vqmmc regulator found\n"); } + if (IS_ERR(mmc->supply.vqmmc2)) { + if (PTR_ERR(mmc->supply.vqmmc2) == -EPROBE_DEFER) + return -EPROBE_DEFER; + dev_dbg(dev, "No vqmmc2 regulator found\n"); + } + return 0; } EXPORT_SYMBOL_GPL(mmc_regulator_get_supply); diff --git a/include/linux/mmc/host.h b/include/linux/mmc/host.h index 0a777caaf7f3..ac9f45e3e203 100644 --- a/include/linux/mmc/host.h +++ b/include/linux/mmc/host.h @@ -65,6 +65,9 @@ struct mmc_ios { #define MMC_TIMING_SD_EXP_1_2V 12 #define MMC_TIMING_SD_UHS2 13 + unsigned char vqmmc2_voltage; +#define MMC_VQMMC2_VOLTAGE_180 0 + unsigned char signal_voltage; /* signalling voltage (1.8V or 3.3V) */ #define MMC_SIGNAL_VOLTAGE_330 0 @@ -299,6 +302,7 @@ struct mmc_pwrseq; struct mmc_supply { struct regulator *vmmc; /* Card power supply */ struct regulator *vqmmc; /* Optional Vccq supply */ + struct regulator *vqmmc2; /* Optional supply for phy */ }; struct mmc_ctx { @@ -579,6 +583,7 @@ int mmc_regulator_set_ocr(struct mmc_host *mmc, struct regulator *supply, unsigned short vdd_bit); int mmc_regulator_set_vqmmc(struct mmc_host *mmc, struct mmc_ios *ios); +int mmc_regulator_set_vqmmc2(struct mmc_host *mmc, struct mmc_ios *ios); #else static inline int mmc_regulator_set_ocr(struct mmc_host *mmc, struct regulator *supply, @@ -592,6 +597,12 @@ static inline int mmc_regulator_set_vqmmc(struct mmc_host *mmc, { return -EINVAL; } + +static inline int mmc_regulator_set_vqmmc2(struct mmc_host *mmc, + struct mmc_ios *ios) +{ + return -EINVAL; +} #endif int mmc_regulator_get_supply(struct mmc_host *mmc); -- 2.25.1
