ENGR00299939-3 USB: imx6x: Add dummy LDO2p5 regulator for VBUS wakeup

LDO2p5 cannot be disabled in low power idle mode when the USB driver
enables VBUS wakeup. To identify when LDO2p5 can be disabled add a dummy
regulator that the USB driver will enable when VBUS wakeup is required.

Signed-off-by: Ranjani Vaidyanathan <Ranjani.Vaidyanathan@freescale.com>
(cherry picked from commit 7d849e4d9ebca3c3c045deca0a12559f84ad6fa1)

1 files changed, 21 insertions, 1 deletions

diff --git a/drivers/usb/chipidea/usbmisc_imx.c b/drivers/usb/chipidea/usbmisc_imx.c
index 803f1ec485d9..4c49d5405a1b 100644
--- a/drivers/usb/chipidea/usbmisc_imx.c
+++ b/drivers/usb/chipidea/usbmisc_imx.c
@@ -15,6 +15,7 @@
 #include <linux/io.h>
 #include <linux/delay.h>
 #include <linux/regmap.h>
+#include <linux/regulator/consumer.h>
 
 #include "ci_hdrc_imx.h"
 
@@ -110,6 +111,8 @@ struct imx_usbmisc {
 	const struct usbmisc_ops *ops;
 };
 
+static struct regulator *vbus_wakeup_reg;
+
 static int usbmisc_imx25_init(struct imx_usbmisc_data *data)
 {
 	struct imx_usbmisc *usbmisc = dev_get_drvdata(data->dev);
@@ -311,13 +314,18 @@ static int usbmisc_imx6q_set_wakeup
 	if (enabled) {
 		wakeup_setting |= imx6q_finalize_wakeup_setting(data);
 		writel(val | wakeup_setting, usbmisc->base + data->index * 4);
+		spin_unlock_irqrestore(&usbmisc->lock, flags);
+		if (vbus_wakeup_reg)
+			ret = regulator_enable(vbus_wakeup_reg);
 	} else {
 		if (val & MX6_BM_WAKEUP_INTR)
 			pr_debug("wakeup int at ci_hdrc.%d\n", data->index);
 		wakeup_setting |= MX6_BM_VBUS_WAKEUP | MX6_BM_ID_WAKEUP;
 		writel(val & ~wakeup_setting, usbmisc->base + data->index * 4);
+		spin_unlock_irqrestore(&usbmisc->lock, flags);
+		if (vbus_wakeup_reg && regulator_is_enabled(vbus_wakeup_reg))
+			regulator_disable(vbus_wakeup_reg);
 	}
-	spin_unlock_irqrestore(&usbmisc->lock, flags);
 
 	return ret;
 }
@@ -619,6 +627,18 @@ static int usbmisc_imx_probe(struct platform_device *pdev)
 	data->ops = (const struct usbmisc_ops *)tmp_dev->data;
 	platform_set_drvdata(pdev, data);
 
+	vbus_wakeup_reg = devm_regulator_get(&pdev->dev, "vbus-wakeup");
+	if (PTR_ERR(vbus_wakeup_reg) == -EPROBE_DEFER)
+		return -EPROBE_DEFER;
+	else if (PTR_ERR(vbus_wakeup_reg) == -ENODEV)
+		/* no vbus regualator is needed */
+		vbus_wakeup_reg = NULL;
+	else if (IS_ERR(vbus_wakeup_reg)) {
+		dev_err(&pdev->dev, "Getting regulator error: %ld\n",
+			PTR_ERR(vbus_wakeup_reg));
+		return PTR_ERR(vbus_wakeup_reg);
+	}
+
 	return 0;
 }