Implement voltage switch callback (shamelessly copied from sunxi mmc driver). This allow, with the appropriate tuning function, to use SD ultra high speed modes.
Signed-off-by: Jerome Brunet <[email protected]> --- drivers/mmc/host/meson-gx-mmc.c | 25 +++++++++++++++++++++++++ 1 file changed, 25 insertions(+) diff --git a/drivers/mmc/host/meson-gx-mmc.c b/drivers/mmc/host/meson-gx-mmc.c index e991c9e452ab..de2d7b8a9d97 100644 --- a/drivers/mmc/host/meson-gx-mmc.c +++ b/drivers/mmc/host/meson-gx-mmc.c @@ -38,6 +38,8 @@ #include <linux/interrupt.h> #include <linux/bitfield.h> +#include <linux/delay.h> + #define DRIVER_NAME "meson-gx-mmc" #define SD_EMMC_CLOCK 0x0 @@ -1024,6 +1026,28 @@ static int meson_mmc_card_busy(struct mmc_host *mmc) return !(FIELD_GET(STATUS_DATI, regval) & 0xf); } +static int meson_mmc_voltage_switch(struct mmc_host *mmc, struct mmc_ios *ios) +{ + /* vqmmc regulator is available */ + if (!IS_ERR(mmc->supply.vqmmc)) { + /* + * The usual amlogic setup uses a GPIO to switch from one + * regulator to the other. While the voltage ramp up is + * pretty fast, care must be taken when switching from 3.3v + * to 1.8v. Please make sure the regulator framework is aware + * of your own regulator constraints + */ + return mmc_regulator_set_vqmmc(mmc, ios); + + } + + /* no vqmmc regulator, assume fixed regulator at 3/3.3V */ + if (ios->signal_voltage == MMC_SIGNAL_VOLTAGE_330) + return 0; + + return -EINVAL; +} + static const struct mmc_host_ops meson_mmc_ops = { .request = meson_mmc_request, .set_ios = meson_mmc_set_ios, @@ -1032,6 +1056,7 @@ static const struct mmc_host_ops meson_mmc_ops = { .post_req = meson_mmc_post_req, .execute_tuning = meson_mmc_execute_tuning, .card_busy = meson_mmc_card_busy, + .start_signal_voltage_switch = meson_mmc_voltage_switch, }; static int meson_mmc_probe(struct platform_device *pdev) -- 2.9.4
