[PATCH V2] mmc: sprd: Fix vqmmc not shutting down after the card was pulled

[Wenchao Chen <wenchao.chen@unisoc.com>]

With cat regulator_summary, we found that vqmmc was not shutting
down after the card was pulled.

cat /sys/kernel/debug/regulator/regulator_summary
1.before fix
1)Insert SD card
 vddsdio		1    1  0 unknown  3500mV 0mA  1200mV  3750mV
    71100000.mmc-vqmmc  1                         0mA  3500mV  3600mV

2)Pull out the SD card
 vddsdio                1    1  0 unknown  3500mV 0mA  1200mV  3750mV
    71100000.mmc-vqmmc  1                         0mA  3500mV  3600mV

2.after fix
1)Insert SD cardt
 vddsdio                1    1  0 unknown  3500mV 0mA  1200mV  3750mV
    71100000.mmc-vqmmc  1                         0mA  3500mV  3600mV

2)Pull out the SD card
 vddsdio		0    1  0 unknown  3500mV 0mA  1200mV  3750mV
    71100000.mmc-vqmmc  0                         0mA  3500mV  3600mV

Fixes: fb8bd90f83c4 ("mmc: sdhci-sprd: Add Spreadtrum's initial host controller")
Signed-off-by: Wenchao Chen <wenchao.chen@unisoc.com>

Change in v2:
- Remove useless sdhci_sprd_signal_voltage_switch and power_mode.
- Use mmc_regulator_get_supply in probe to prevent sdhci_setup_host
  from powering up vqmmc.
---
 drivers/mmc/host/sdhci-sprd.c | 25 +++++++++++++++++++++++++
 1 file changed, 25 insertions(+)

diff --git a/drivers/mmc/host/sdhci-sprd.c b/drivers/mmc/host/sdhci-sprd.c
index 6b84ba27e6ab..6b8a57e2d20f 100644
--- a/drivers/mmc/host/sdhci-sprd.c
+++ b/drivers/mmc/host/sdhci-sprd.c
@@ -416,12 +416,33 @@ static void sdhci_sprd_request_done(struct sdhci_host *host,
 	mmc_request_done(host->mmc, mrq);
 }
 
+static void sdhci_sprd_set_power(struct sdhci_host *host, unsigned char mode,
+				 unsigned short vdd)
+{
+	struct mmc_host *mmc = host->mmc;
+
+	switch (mode) {
+	case MMC_POWER_OFF:
+		mmc_regulator_set_ocr(host->mmc, mmc->supply.vmmc, 0);
+
+		mmc_regulator_disable_vqmmc(mmc);
+		break;
+	case MMC_POWER_ON:
+		mmc_regulator_enable_vqmmc(mmc);
+		break;
+	case MMC_POWER_UP:
+		mmc_regulator_set_ocr(host->mmc, mmc->supply.vmmc, vdd);
+		break;
+	}
+}
+
 static struct sdhci_ops sdhci_sprd_ops = {
 	.read_l = sdhci_sprd_readl,
 	.write_l = sdhci_sprd_writel,
 	.write_w = sdhci_sprd_writew,
 	.write_b = sdhci_sprd_writeb,
 	.set_clock = sdhci_sprd_set_clock,
+	.set_power = sdhci_sprd_set_power,
 	.get_max_clock = sdhci_sprd_get_max_clock,
 	.get_min_clock = sdhci_sprd_get_min_clock,
 	.set_bus_width = sdhci_set_bus_width,
@@ -823,6 +844,10 @@ static int sdhci_sprd_probe(struct platform_device *pdev)
 	host->caps1 &= ~(SDHCI_SUPPORT_SDR50 | SDHCI_SUPPORT_SDR104 |
 			 SDHCI_SUPPORT_DDR50);
 
+	ret = mmc_regulator_get_supply(host->mmc);
+	if (ret)
+		goto pm_runtime_disable;
+
 	ret = sdhci_setup_host(host);
 	if (ret)
 		goto pm_runtime_disable;
-- 
2.17.1