For Spreadtrum SD host controller, we can not use standard SD registers
to change and detect the I/O voltage signals, since our voltage regulator
for I/O is fixed in hardware, and no signals were connected to the SD
controller. Thus add Spreadtrum specific voltage switch ops to change
voltage instead of using standard SD host registers.
Signed-off-by: Baolin Wang <baolin.wang@xxxxxxxxxx>
---
drivers/mmc/host/sdhci-sprd.c | 24 ++++++++++++++++++++++++
1 file changed, 24 insertions(+)
diff --git a/drivers/mmc/host/sdhci-sprd.c b/drivers/mmc/host/sdhci-sprd.c
index 024c3c5..8b23c88 100644
--- a/drivers/mmc/host/sdhci-sprd.c
+++ b/drivers/mmc/host/sdhci-sprd.c
@@ -403,6 +403,22 @@ static void sdhci_sprd_request(struct mmc_host *mmc, struct mmc_request *mrq)
sdhci_request(mmc, mrq);
}
+static int sdhci_sprd_voltage_switch(struct mmc_host *mmc, struct mmc_ios *ios)
+{
+ int ret;
+
+ if (!IS_ERR(mmc->supply.vqmmc)) {
+ ret = mmc_regulator_set_vqmmc(mmc, ios);
+ if (ret) {
+ pr_err("%s: Switching signalling voltage failed\n",
+ mmc_hostname(mmc));
+ return ret;
+ }
+ }
+
+ return 0;
+}
+
static void sdhci_sprd_hs400_enhanced_strobe(struct mmc_host *mmc,
struct mmc_ios *ios)
{
@@ -470,6 +486,14 @@ static int sdhci_sprd_probe(struct platform_device *pdev)
host->mmc_host_ops.request = sdhci_sprd_request;
host->mmc_host_ops.hs400_enhanced_strobe =
sdhci_sprd_hs400_enhanced_strobe;
+ /*
+ * We can not use the standard ops to change and detect the voltage
+ * signal for Spreadtrum SD host controller, since our voltage regulator
+ * for I/O is fixed in hardware, that means we do not need control
+ * the standard SD host controller to change the I/O voltage.
+ */
+ host->mmc_host_ops.start_signal_voltage_switch =
+ sdhci_sprd_voltage_switch;
host->mmc->caps = MMC_CAP_SD_HIGHSPEED | MMC_CAP_MMC_HIGHSPEED |
MMC_CAP_ERASE | MMC_CAP_CMD23;
--
1.7.9.5
