From: Victor Gu <xigu@xxxxxxxxxxx>
Some host controller such as Xenon needs additional setting when
switching signal voltage in eMMC mode. They also need to re-enable
internal clock before a voltage switch.
This commit adds a callback routine "voltage_switch_pre" in the struct
sdhci_ops, which is used by some host controllers which need re-enable
the internal clock before a voltage switch.
[gregory.clement@xxxxxxxxxxxxxxxxxx: split the initial commit and
reformulate the log]
Signed-off-by: Victor Gu <xigu@xxxxxxxxxxx>
Signed-off-by: Marcin Wojtas <mw@xxxxxxxxxxxx>
Signed-off-by: Gregory CLEMENT <gregory.clement@xxxxxxxxxxxxxxxxxx>
---
drivers/mmc/host/sdhci.c | 4 ++++
drivers/mmc/host/sdhci.h | 1 +
2 files changed, 5 insertions(+)
diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
index b07219426d39..cad03ffa9d9b 100644
--- a/drivers/mmc/host/sdhci.c
+++ b/drivers/mmc/host/sdhci.c
@@ -1729,6 +1729,10 @@ static int sdhci_start_signal_voltage_switch(struct mmc_host *mmc,
if (host->version < SDHCI_SPEC_300)
return 0;
+ /* Some controller need to do more before switching */
+ if (host->ops->voltage_switch_pre)
+ host->ops->voltage_switch_pre(host);
+
ctrl = sdhci_readw(host, SDHCI_HOST_CONTROL2);
switch (ios->signal_voltage) {
diff --git a/drivers/mmc/host/sdhci.h b/drivers/mmc/host/sdhci.h
index 49c6c5b0e33b..6bec1b0368d2 100644
--- a/drivers/mmc/host/sdhci.h
+++ b/drivers/mmc/host/sdhci.h
@@ -550,6 +550,7 @@ struct sdhci_ops {
unsigned int max_dtr, int host_drv,
int card_drv, int *drv_type);
void (*init_card)(struct sdhci_host *host, struct mmc_card *card);
+ void (*voltage_switch_pre)(struct sdhci_host *host);
};
#ifdef CONFIG_MMC_SDHCI_IO_ACCESSORS
--
2.5.0
--
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