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mmc: meson-gx: implement voltage switch callback 

Implement voltage switch callback (shamelessly copied from sunxi mmc
driver). This allow, with the appropriate tuning function, to use
SD ultra high speed modes.

Reviewed-by: Kevin Hilman <khilman@baylibre.com>
Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
This commit is contained in:
Jerome Brunet 2017-08-28 16:29:13 +02:00 committed by Ulf Hansson
parent 033d716859
commit b1231b2f73
1 changed files with 22 additions and 0 deletions
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22
drivers/mmc/host/meson-gx-mmc.c
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@ -1049,6 +1049,27 @@ 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,
@ -1057,6 +1078,7 @@ 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)