[PATCH 03/10] mmc: sdhci-of-k1: add regulator framework support

[Iker Pedrosa]

Add regulator framework support for voltage switching operations. This
enables proper PMIC control for UHS voltage switching between 3.3V and
1.8V signaling levels.

- Add regulator supply parsing
- Implement voltage switching callback
- Enable mmc regulator framework integration

Signed-off-by: Iker Pedrosa <ikerpedrosam at gmail.com>
---
 drivers/mmc/host/sdhci-of-k1.c | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/drivers/mmc/host/sdhci-of-k1.c b/drivers/mmc/host/sdhci-of-k1.c
index b703b78282ed8d89183c816477c149c0a565618a..c260cb89704ae7a25bec0f07831d495553405bbd 100644
--- a/drivers/mmc/host/sdhci-of-k1.c
+++ b/drivers/mmc/host/sdhci-of-k1.c
@@ -216,6 +216,12 @@ static void spacemit_sdhci_pre_hs400_to_hs200(struct mmc_host *mmc)
 			       SPACEMIT_SDHC_PHY_CTRL_REG);
 }
 
+static int spacemit_sdhci_start_signal_voltage_switch(struct mmc_host *mmc,
+						      struct mmc_ios *ios)
+{
+	return sdhci_start_signal_voltage_switch(mmc, ios);
+}
+
 static inline int spacemit_sdhci_get_clocks(struct device *dev,
 					    struct sdhci_pltfm_host *pltfm_host)
 {
@@ -291,6 +297,12 @@ static int spacemit_sdhci_probe(struct platform_device *pdev)
 
 	host->mmc->caps |= MMC_CAP_NEED_RSP_BUSY;
 
+	ret = mmc_regulator_get_supply(host->mmc);
+	if (ret)
+		dev_warn(dev, "Failed to get regulators: %d\n", ret);
+
+	host->mmc_host_ops.start_signal_voltage_switch = spacemit_sdhci_start_signal_voltage_switch;
+
 	ret = spacemit_sdhci_get_clocks(dev, pltfm_host);
 	if (ret)
 		goto err_pltfm;

-- 
2.53.0